[top]
000
FXUS66 KPDT 101130 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
430 AM PDT FRI OCT 10 2008
UPDATED AVIATION DISCUSSION
.SHORT TERM...A LARGE UPPER LOW PRESSURE SYSTEM IS CONTINUING TO
DEEPEN THIS MORNING OVER THE PACIFIC NORTHWEST. WRAP AROUND MOISTURE
COMBINED WITH UP SLOPE TERRAIN EFFECTS BEHIND THE LOW ARE CAUSING
SNOW SHOWERS TO PERSIST OVER THE HIGH TERRAIN OF CENTRAL AND EAST
CENTRAL OREGON THIS MORNING. SOME AREAS ARE LIKELY TO RECEIVE
SEVERAL INCHES OF SNOW...MAKING THIS THE FIRST APPRECIABLE SNOWFALL
OF THE SEASON. AREAS OF PARTICULAR CONCERN INCLUDE THE DESCHUTES
PLATEAU AND THE JOHN DAY HIGHLANDS/BASIN. A WINTER WEATHER ADVISORY
FOR SNOW WILL REMAIN IN EFFECT FOR THESE AREAS UNTIL 10 AM THIS
MORNING. IN OTHER AREAS THE SNOW IS NOT EXPECTED TO BE ENOUGH FOR AN
ADVISORY OR WARNING. A DEEP NORTHERLY FLOW ON THE BACK SIDE OF THE
UPPER LOW WILL KEEP DRY BUT VERY COLD AIR OVER THE FORECAST AREA
TODAY THROUGH SATURDAY. MANY LOCATIONS MAY SEE RECORD LOW
TEMPERATURES TONIGHT. SOME LOCATIONS SUCH AS THE YAKIMA/KITTITAS
VALLEYS AND THE LOWER COLUMBIA BASIN/BLUE MOUNTAIN FOOTHILLS OF
WASHINGTON WILL NEED A FREEZE WARNING FOR TONIGHT. CONDITIONS WILL
BEGIN TO GRADUALLY WARM UP BEGINNING ON SUNDAY AND PERSISTING INTO
THE EXTENDED PERIOD. 88
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...HIGHER PRESSURE WILL
BUILD OVER THE AREA SUNDAY NIGHT AND MONDAY...WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. ON TUESDAY...A WESTERLY FLOW WILL BRING
ANOTHER FRONTAL SYSTEM INTO THE REGION. HOWEVER...THE RELATIVELY DRY
AIR MASS THAT WILL ACCOMPANY THIS FLOW WILL LIMIT PRECIPITATION. AS
A RESULT...ONLY MOUNTAIN SHOWERS ARE EXPECTED THROUGH WEDNESDAY.
RIDGING IS LIKELY TO RETURN ON THURSDAY...PROVIDING A BREAK IN THE
ACTIVITY. YET ANOTHER DISTURBANCE IS THEN FORECAST TO MOVE INLAND ON
FRIDAY...ONCE AGAIN TRIGGERING MOUNTAIN SHOWERS. TEMPERATURES WILL
REMAIN NEAR NORMAL THROUGHOUT THE PERIOD. CALDER
&&
.AVIATION...12Z TAFS...THE WEATHER DISTURBANCE THAT IS BRINGING
SHOWERS TO CENTRAL AND NORTHEAST OREGON AND SOUTHEAST WASHINGTON
WILL MOVE SOUTH AND OUT OF THE AREA TODAY. THEREFORE...VFR
CONDITIONS CAN BE EXPECTED AT ALL SITES THROUGH SATURDAY MORNING.
THE EXCEPTION WILL BE KALW...WHERE HEAVIER SHOWERS COULD BRIEFLY
LOWER CEILINGS AND VISIBILITY TO MVFR THIS MORNING. WINDS WILL
BECOME BREEZY...PRECIPITATION WILL DECREASE AND SKIES WILL GRADUALLY
CLEAR BY LATE MORNING/EARLY AFTERNOON. 82
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 55 29 55 32 / 30 0 0 0
ALW 57 30 57 33 / 10 0 0 0
PSC 59 27 59 30 / 10 0 0 0
YKM 56 25 56 28 / 0 0 0 0
HRI 57 27 57 30 / 10 0 0 0
ELN 56 26 56 29 / 0 0 0 0
RDM 48 22 48 25 / 60 10 0 0
LGD 49 26 49 29 / 40 20 0 0
GCD 49 24 49 27 / 60 20 0 0
DLS 60 29 60 32 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PDT THIS MORNING FOR ORZ043-
505-506.
WA...FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR WAZ026-027.
FREEZE WARNING FROM 8 PM THIS EVENING TO 10 AM PDT SATURDAY FOR
WAZ026-027-028-029.
&&
$$
TI:YGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
88/82/82
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000
FXUS66 KMFR 101034
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
334 AM PDT FRI OCT 10 2008
.SHORT TERM...AN UPPER LEVEL TROUGH OVER THE REGION IS BRINGING
SCATTERED SHOWERS TO THE AREA THIS MORNING. SHOWERS ARE MAINLY
LIGHT ACROSS THE AREA. COLD AIR ADVECTION IN NORTHERLY FLOW HAS
LOWERED SNOW LEVELS TO AROUND 3000 FEET THIS MORNING AND LOCALLY
LOWER. SNOW SHOWERS ARE MAINLY LIGHT AND WARMER GROUND
TEMPERATURES SHOULD LIMIT ANY ACCUMULATIONS TO ABOVE 5000 FEET.
AS THE LOW GRADUALLY MOVES SOUTH THIS AFTERNOON THE UPPER LEVEL
JET ALONG THE COAST WILL SHIFT SOUTH OF THE AREA...SHOWERS WILL
TAPER OFF WEST OF THE CASCADES WITH CONTINUED SHOWERS FROM THE
CASCADES EASTWARD IN THE COLD UNSTABLE AIRMASS. TEMPERATURES
TODAY WILL REMAIN COOL WITH HIGHS ONLY IN THE 50S FOR INLAND WEST
SIDE VALLEYS AND IN THE 40S FOR AREAS EAST OF THE CASCADES.
THEN...AS THE SYSTEM SHIFTS SLIGHTLY SOUTHEAST IN THE EVENING AND
OVERNIGHT...SHOWERS EAST OF THE CASCADES SHOULD DIMINISH.
FRIDAY NIGHT...EXPECT CLEAR TO PARTLY CLOUDY SKIES...THIS COMBINED
WITH COLD AIR IN PLACE WILL BRING COLD TEMPERATURES OVER MUCH OF
THE AREA. INLAND AREAS WEST OF THE CASCADES WILL LIKELY LOWER
INTO THE UPPER 20S TO MID 30S WITH TEMPERATURES IN THE TEENS AND
LOW 20S EAST OF THE CASCADES. ON SATURDAY THE UPPER LOW WILL
GRADUALLY MOVE EAST INTO NEVADA AND UTAH. AS THE UPPER LOW SHIFTS
EAST...BREEZY NORTH TO NORTHEAST FLOW WILL REMAIN OVER THE
AREA...SO EXPECT ONLY SLIGHTLY WARMER CONDITIONS ON SATURDAY WITH
ANOTHER COLD NIGHT EXPECTED SATURDAY NIGHT INTO SUNDAY MORNING.
ON SUNDAY A RIDGE WILL BEGIN TO BUILD INTO THE AREA FROM
OFFSHORE. THIS WILL BRING SLIGHTLY WARMER TEMPERATURES TO THE
AREA.
&&
.AVIATION...SCATTERED SHOWERS WILL REMAIN OVER THE AREA THIS
MORNING THEN TAPER OFF WEST OF THE CASCADES IN THE LATE MORNING
AND EARLY AFTERNOON WITH CONTINUING SHOWERS FROM THE CASCADES
EAST THIS AFTERNOON AND EVENING. EXPECT AREAS OF MVFR CIGS THIS
MORNING FROM THE CASCADES WEST...BECOMING ISOLATED IN THE LATE
MORNING. EAST OF THE CASCADES ISOLATED MVFR CIGS WILL CONTINUE
INTO FRIDAY EVENING. AREAS OF MOUNTAIN OBSCURATIONS BECOMING
ISOLATED THIS EVENING.
&&
.PREV LONG TERM DISCUSSION... /ISSUED 905 PM PDT THU OCT 9 2008/
A NORTH TO NORTHEAST LOW WILL REMAIN OVER THE CWA OVER THE WEEKEND
AND AT THE SAME TIME THE RIDGE AXIS WILL SLOWLY SHIFT EAST TOWARDS
THE CWA. THE NET RESULT WILL BE DRY CONDITIONS. TEMPERATURES WILL
BE MILDER SATURDAY AND SUNDAY AFTERNOONS...BUT STILL COLD AT
NIGHT.
THE RIDGE WILL FLATTEN OUT SOME BY THE START OF NEXT WEEK AS WEAK
SHORTWAVE MOVES NORTH OF THE AREA...BUT ANY PRECIPITATION WILL
REMAIN NORTH OF THE CWA. BEYOND MONDAY...BOTH THE GFS AND ECMWF
SHOW A WEST TO NORTHWEST FLOW ALOFT WHICH WITH A FEW WEAK
DISTURBANCES PASSING BY TO THE NORTH. AT THIS TIME IT LOOKS LIKE
MOST OF NEXT WEEK WILL BE DRY WITH TEMPERATURES NEAR NORMAL.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
CA...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR CAZ080-CAZ081-
CAZ082.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR CAZ080-CAZ081-
CAZ082.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM
PDT SATURDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PDT SATURDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
CC
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000
FXUS66 KPQR 101000
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
258 AM PDT FRI OCT 10 2008
.SYNOPSIS...COLDER AIR IS SETTLING OVER THE AREA AS AN UPPER LEVEL
TROUGH PLACES THE REGION IN A NORTHWEST FLOW. THE UPPER LEVEL TROUGH
WILL SHIFT EAST BEGINNING TODAY AND SHOWERS WILL SUBSIDE AS A RIDGE
OF HIGH PRESSURE ALOFT BUILDS OFFSHORE. THE RIDGE WILL MOVE INLAND BY
SUNDAY...BUT IS EXPECTED TO BREAK DOWN EARLY NEXT WEEK...ALLOWING A
PACIFIC COLD FRONT TO MOVE INLAND BRUSHING THE NORTH.
&&
.SHORT TERM...AN UPPER LOW IS NOW OVER SOUTHEAST OREGON AND IDAHO.
SHOWERS ON THE WESTERN REACHES OF THE LOW HAVE BEEN DRIFTING NORTH TO
SOUTH OVER THE FORECAST AREA. MAIN ACTIVITY IS NOW OVER THE SOUTHERN
HALF OF THE AREA AND CONTINUE TO DIMINISH. FREEZING LEVEL AROUND
3500-4000 FEET PER 07Z AIRCRAFT SOUNDING...PLACING SNOW LEVEL DOWN TO
AROUND 2500 FEET. BASED ON RADAR AND SATELLITE LIGHT SNOW SHOWERS
LIMITED TO LANE COUNTY CASCADES EARLY THIS MORNING.
EXPECT THE COOLEST NIGHT OF THE FALL BY SAT MORNING. SOME TEMPS
LIKELY NEAR FREEZING IN THE OUTLYING AREAS AWAY FROM THE CITY HEAT
ISLANDS. ALSO FOG DEVELOPS LATER TONIGHT INTO SATURDAY MORNING WILL
PROBABLY INHIBIT WIDESPREAD FREEZING TEMPERATURES IN THE LOWLANDS.
SIMILARLY COLD STARTS FOR SUN MORNING AS THE AIR MASS DRIES OUT.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
THE MODELS ARE VARYING BUT LOOKS LIKE THE RIDGE STAYS STRONG ENOUGH
TO KEEP MOST OF THE PRECIPITATION TO THE NORTH BRUSHING THE NORTHWEST
PART OF THE FORECAST AREA AT TIMES INTO THE EXTENDED.
&&
.AVIATION...VFR CONDITIONS MIXED WITH MVFR CIGS BOTH FROM SHOWERS
AND AREAS OF LOW CLOUDS THIS MORNING. COULD SEE PATCHES OF IFR
CONDITIONS FROM FOG IN AREAS WITH CLOUD BREAKS THIS MORNING.
CONDITIONS WILL IMPROVE TO VFR THIS AFTERNOON EXCEPT FOR SOME LINGER
SHOWERS AND MTN OBSCURATION OVER THE CASCADES AND POSSIBLY THE COAST
RANGE. TOLLESON
.KPDX AND APPROACHES...MVFR CONDITIONS FROM LOW CLOUDS AND A FEW
RESIDUAL SHOWERS. CONDITIONS LIFTING TO VFR IN THE AFTERNOON.
TOLLESON
&&
.MARINE...BRISK SMALL CRAFT WINDS CONTINUE OVER THE COASTAL WATERS
THIS MORNING AS THE LAST MAIN DISTURBANCE MOVES SOUTH. WINDS WILL
DECREASE FROM THE NORTH THROUGH THE MORNING AND EARLY
AFTERNOON...THEN RETURN TO THE CENTRAL COAST LATE IN THE AFTERNOON
AND EVENING AS THE THERMAL STRENGTHENS TO OUR SOUTH. SEAS ABOVE 10
FT THIS MORNING WILL DROP IN THE NORTH BY EARLY AFTERNOON AND IN THE
SOUTH IN THE EARLY EVENING. WILL STILL HAVE A ROUGH COLUMBIA RIVER
BAR AT THE MORNING EBB. TOLLESON
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO CASCADE
HEAD THIS MORNING.
SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
THROUGH THIS EVENING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE
SHOALWATER TO CASCADE HEAD THROUGH THIS MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CASCADE HEAD TO
FLORENCE THROUGH TODAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THROUGH FRIDAY
MORNING
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 100926
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
225 AM PDT FRI OCT 10 2008
.SHORT TERM...A LARGE UPPER LOW PRESSURE SYSTEM IS CONTINUING TO
DEEPEN THIS MORNING OVER THE PACIFIC NORTHWEST. WRAP AROUND MOISTURE
COMBINED WITH UP SLOPE TERRAIN EFFECTS BEHIND THE LOW ARE CAUSING
SNOW SHOWERS TO PERSIST OVER THE HIGH TERRAIN OF CENTRAL AND EAST
CENTRAL OREGON THIS MORNING. SOME AREAS ARE LIKELY TO RECEIVE
SEVERAL INCHES OF SNOW...MAKING THIS THE FIRST APPRECIABLE SNOWFALL
OF THE SEASON. AREAS OF PARTICULAR CONCERN INCLUDE THE DESCHUTES
PLATEAU AND THE JOHN DAY HIGHLANDS/BASIN. A WINTER WEATHER ADVISORY
FOR SNOW WILL REMAIN IN EFFECT FOR THESE AREAS UNTIL 10 AM THIS
MORNING. IN OTHER AREAS THE SNOW IS NOT EXPECTED TO BE ENOUGH FOR AN
ADVISORY OR WARNING. A DEEP NORTHERLY FLOW ON THE BACK SIDE OF THE
UPPER LOW WILL KEEP DRY BUT VERY COLD AIR OVER THE FORECAST AREA
TODAY THROUGH SATURDAY. MANY LOCATIONS MAY SEE RECORD LOW
TEMPERATURES TONIGHT. SOME LOCATIONS SUCH AS THE YAKIMA/KITTITAS
VALLEYS AND THE LOWER COLUMBIA BASIN/BLUE MOUNTAIN FOOTHILLS OF
WASHINGTON WILL NEED A FREEZE WARNING FOR TONIGHT. CONDITIONS WILL
BEGIN TO GRADUALLY WARM UP BEGINNING ON SUNDAY AND PERSISTING INTO
THE EXTENDED PERIOD. 88
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...HIGHER PRESSURE WILL
BUILD OVER THE AREA SUNDAY NIGHT AND MONDAY...WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. ON TUESDAY...A WESTERLY FLOW WILL BRING
ANOTHER FRONTAL SYSTEM INTO THE REGION. HOWEVER...THE RELATIVELY DRY
AIR MASS THAT WILL ACCOMPANY THIS FLOW WILL LIMIT PRECIPITATION. AS
A RESULT...ONLY MOUNTAIN SHOWERS ARE EXPECTED THROUGH WEDNESDAY.
RIDGING IS LIKELY TO RETURN ON THURSDAY...PROVIDING A BREAK IN THE
ACTIVITY. YET ANOTHER DISTURBANCE IS THEN FORECAST TO MOVE INLAND ON
FRIDAY...ONCE AGAIN TRIGGERING MOUNTAIN SHOWERS. TEMPERATURES WILL
REMAIN NEAR NORMAL THROUGHOUT THE PERIOD. CALDER
&&
.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...A WEATHER DISTURBANCE
BRINGING SHOWERS ACROSS CENTRAL AND NORTHEAST OREGON AND SOUTHEAST
WASHINGTON WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY OVERNIGHT AND
INTO TOMORROW MORNING. CEILINGS WILL BE MOSTLY VFR OVER THE AREA.
THE EXCEPTION IS KRDM AND UNDER THE HEAVIER SNOW SHOWERS OVER THE
HIGHER TERRAIN OF OREGON WHERE CEILINGS WILL BE IN THE MVFR AND
POSSIBLE LOCAL IFR CATEGORIES. VISIBILITIES MAY DROP UNDER THE
HEAVIEST SHOWERS BY TOMORROW MORNING. WINDS WILL BECOME
BREEZY...PRECIPITATION WILL DECREASE AND SKIES WILL GRADUALLY CLEAR
BY LATE MORNING AND EARLY AFTERNOON TOMORROW. DMH
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 55 29 55 32 / 30 0 0 0
ALW 57 30 57 33 / 10 0 0 0
PSC 59 27 59 30 / 10 0 0 0
YKM 56 25 56 28 / 0 0 0 0
HRI 57 27 57 30 / 10 0 0 0
ELN 56 26 56 29 / 0 0 0 0
RDM 48 22 48 25 / 60 10 0 0
LGD 49 26 49 29 / 40 20 0 0
GCD 49 24 49 27 / 60 20 0 0
DLS 60 29 60 32 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PDT THIS MORNING FOR ORZ043-
505-506.
WA...FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR WAZ026-027.
FREEZE WARNING FROM 8 PM THIS EVENING TO 10 AM PDT SATURDAY FOR
WAZ026-027-028-029.
&&
$$
TI:YGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
88/82/82
000
FXUS66 KPDT 100925
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
225 AM PDT FRI OCT 10 2008
.SHORT TERM...A LARGE UPPER LOW PRESSURE SYSTEM IS CONTINUING TO
DEEPEN THIS MORNING OVER THE PACIFIC NORTHWEST. WRAP AROUND MOISTURE
COMBINED WITH UP SLOPE TERRAIN EFFECTS BEHIND THE LOW ARE CAUSING
SNOW SHOWERS TO PERSIST OVER THE HIGH TERRAIN OF CENTRAL AND EAST
CENTRAL OREGON THIS MORNING. SOME AREAS ARE LIKELY TO RECEIVE
SEVERAL INCHES OF SNOW...MAKING THIS THE FIRST APPRECIABLE SNOWFALL
OF THE SEASON. AREAS OF PARTICULAR CONCERN INCLUDE THE DESCHUTES
PLATEAU AND THE JOHN DAY HIGHLANDS/BASIN. A WINTER WEATHER ADVISORY
FOR SNOW WILL REMAIN IN EFFECT FOR THESE AREAS UNTIL 10 AM THIS
MORNING. IN OTHER AREAS THE SNOW IS NOT EXPECTED TO BE ENOUGH FOR AN
ADVISORY OR WARNING. A DEEP NORTHERLY FLOW ON THE BACK SIDE OF THE
UPPER LOW WILL KEEP DRY BUT VERY COLD AIR OVER THE FORECAST AREA
TODAY THROUGH SATURDAY. MANY LOCATIONS MAY SEE RECORD LOW
TEMPERATURES TONIGHT. SOME LOCATIONS SUCH AS THE LOWER COLUMBIA
BASIN AND BLUE MOUNTAIN FOOTHILLS OF WASHINGTON WILL PROBABLY NEED A
FREEZE WARNING FOR TONIGHT. CONDITIONS WILL BEGIN TO GRADUALLY WARM
UP BEGINNING ON SUNDAY AND PERSISTING INTO THE EXTENDED PERIOD. 88
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...HIGHER PRESSURE WILL
BUILD OVER THE AREA SUNDAY NIGHT AND MONDAY...WITH MOSTLY CLEAR
SKIES AND LIGHT WINDS. ON TUESDAY...A WESTERLY FLOW WILL BRING
ANOTHER FRONTAL SYSTEM INTO THE REGION. HOWEVER...THE RELATIVELY DRY
AIR MASS THAT WILL ACCOMPANY THIS FLOW WILL LIMIT PRECIPITATION. AS
A RESULT...ONLY MOUNTAIN SHOWERS ARE EXPECTED THROUGH WEDNESDAY.
RIDGING IS LIKELY TO RETURN ON THURSDAY...PROVIDING A BREAK IN THE
ACTIVITY. YET ANOTHER DISTURBANCE IS THEN FORECAST TO MOVE INLAND ON
FRIDAY...ONCE AGAIN TRIGGERING MOUNTAIN SHOWERS. TEMPERATURES WILL
REMAIN NEAR NORMAL THROUGHOUT THE PERIOD. CALDER
&&
.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...A WEATHER DISTURBANCE
BRINGING SHOWERS ACROSS CENTRAL AND NORTHEAST OREGON AND SOUTHEAST
WASHINGTON WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY OVERNIGHT AND
INTO TOMORROW MORNING. CEILINGS WILL BE MOSTLY VFR OVER THE AREA.
THE EXCEPTION IS KRDM AND UNDER THE HEAVIER SNOW SHOWERS OVER THE
HIGHER TERRAIN OF OREGON WHERE CEILINGS WILL BE IN THE MVFR AND
POSSIBLE LOCAL IFR CATEGORIES. VISIBILITIES MAY DROP UNDER THE
HEAVIEST SHOWERS BY TOMORROW MORNING. WINDS WILL BECOME
BREEZY...PRECIPITATION WILL DECREASE AND SKIES WILL GRADUALLY CLEAR
BY LATE MORNING AND EARLY AFTERNOON TOMORROW. DMH
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 55 29 55 32 / 30 0 0 0
ALW 57 30 57 33 / 10 0 0 0
PSC 59 27 59 30 / 10 0 0 0
YKM 56 25 56 28 / 0 0 0 0
HRI 57 27 57 30 / 10 0 0 0
ELN 56 26 56 29 / 0 0 0 0
RDM 48 22 48 25 / 60 10 0 0
LGD 49 26 49 29 / 40 20 0 0
GCD 49 24 49 27 / 60 20 0 0
DLS 60 29 60 32 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PDT THIS MORNING FOR ORZ043-
505-506.
WA...FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR WAZ026-027.
FREEZE WARNING FROM 8 PM THIS EVENING TO 10 AM PDT SATURDAY FOR
WAZ026-027-028-029.
&&
$$
TI:YGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
88/82/82
[top]
000
FXUS65 KBOI 100900
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
300 AM MDT FRI OCT 10 2008
.SHORT TERM...TODAY THROUGH SATURDAY...EARLY SEASON WINTER-LIKE
STORM IS SHAPING UP OVER THE FORECAST AREA. THE UPPER LEVEL LOW IS
OVER THE FORECAST AREA THIS MORNING AND WILL MOVE SLOWLY SOUTHEAST
TO UTAH BY LATE SATURDAY. CURRENT FORECAST LOOKS GOOD AND ONLY MADE
MINOR CHANGES. STRONG NORTHWEST WINDS OF 25 TO 40 MPH WITH GUSTS TO
55 MPH WILL DEVELOP BY THIS AFTERNOON ALONG A CORRIDOR FROM ONTARIO
TO BAKER. WINDS WILL DECREASE TONIGHT IN THIS AREA BUT INCREASE
AGAIN SATURDAY AFTERNOON. WILL CONTINUE THE WIND ADVISORY FOR THIS
AREA. THERE WAS SOME CONCERN PASSED ON BY THE EVENING SHIFT THAT
WINDS MAY BE STRONG ENOUGH OVER HARNEY COUNTY TO BE INCLUDED IN THE
ADVISORY. AFTER LOOKING OVER THE MODELS THINK WINDS WILL BE NEAR
ADVISORY LEVELS BUT NOT HIGH ENOUGH TO HAVE A WINDS ADVISORY. SO
FAR THIS MORNING NOT MUCH IN THE WAY OF RAIN AND SNOW SHOWERS WITH
RADAR SHOWING SHOWERS ALL AROUND THE FORECAST AREA. EXPECT RAIN AND
SNOW SHOWERS TO PICK UP BY THIS AFTERNOON AS THE UPPER LEVEL LOW
MOVES TO THE SOUTHEAST. WITH THE COLDER AIR STILL TO MOVE INTO THE
AREA SNOW LEVELS WILL CONTINUE TO FALL AND WILL BE NEAR THE VALLEY
FLOOR THIS MORNING. AS THE UPPER LEVEL LOW DIVES TO THE SOUTHEAST
TONIGHT AND SATURDAY MOISTURE WRAPPING AROUND THE LOW WILL MOVE INTO
PORTIONS OF SOUTHWEST IDAHO. FORECAST TRACK OF THE LOW CONTINUES
TO FAVOR SIGNIFICANT SNOW IN THE WESTERN MAGIC VALLEY AND SOUTHERN
TWIN FALLS COUNTY. STILL SOME UNCERTAINTY IN THE EXACT TRACK OF THE
LOW SO WILL LEAVE AS A WINTER STORM WATCH FOR NOW.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY...SNOW AND GUSTY W-NW
WINDS WILL STILL BE IN SCENTRAL IDAHO SATURDAY NIGHT AS THE MAIN LOW
HEADS NE THROUGH WYOMING. OREGON ZONES WILL ALREADY BE CLEARING
SATURDAY NIGHT. CLEARING AND MILDER WX WILL MOVE INTO IDAHO SUNDAY
AS UPPER RIDGE OVER THE NORTH PACIFIC MOVES INLAND. TEMPERATURES
WILL RECOVER TO NORMAL BY TUESDAY. BOTH GFS AND ECM BRING A WEAK
SHORT WAVE TROUGH EWD ACROSS IDAHO WEDNESDAY FOR A SLIGHT CHANCE OF
SHOWERS IN OUR NRN ZONES...AND SLIGHT COOLING IN ALL ZONES. UPPER
RIDGE IS PROGGED TO REBUILD OVER OUR AREA THURSDAY AND ESPECIALLY
FRIDAY...MAX TEMPS RISING TO ABOUT 5F ABOVE NORMAL FRIDAY UNDER
MOSTLY CLEAR SKIES.
&&
.AVIATION...MVFR CEILINGS AND VISIBILITIES IN -SHSN IN CENTRAL OREGON
THIS MORNING...VFR ELSEWHERE WITH ONLY SCATTERED CLOUDS. CONDITIONS
WILL DETERIORATE FROM THE NW TODAY AS UPPER TROUGH CONTINUES TO
INTENSIFY AS IT MOVES SSEWD THROUGH WRN IDAHO THIS MORNING AND INTO
NEVADA MIDDAY TODAY. BY 20Z SCATTERED TO NUMEROUS -SHSN WILL
DEVELOP THROUGHOUT SWRN IDAHO AND SERN OREGON CAUSING WIDESPREAD
MVFR CONDS AND MOUNTAIN OBSCURATION...AND AREAS OF IFR. THESE
CONDITIONS WILL REACH SCENTRAL IDAHO THIS EVENING AND CONTINUE
THERE INTO SATURDAY. NW-SE PRESSURE GRADIENT WILL DEVELOP NWLY
SURFACE WINDS 30-45 KTS IN ERN OREGON 16Z-24Z TODAY...15-30 KTS IN
SWRN IDAHO. SURFACE WINDS IN OREGON WILL DECREASE TO 20-30 KTS
TONIGHT BUT WILL INCREASE TO TODAY/S SPEEDS AGAIN ON SATURDAY.
SURFACE WINDS IN IDAHO WILL INCREASE TO 20-30 KTS SATURDAY. WINDS
ALOFT WILL BE MODERATE NELY THROUGH SATURDAY IN ALL AREAS.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER STORM WATCH FROM LATE TONIGHT THROUGH SATURDAY EVENING
FOR IDZ016-IDZ030.
WIND ADVISORY FROM 12 PM TO 9 PM MDT TODAY FOR IDZ011-IDZ012.
WIND ADVISORY FROM 12 PM TO 9 PM MDT SATURDAY FOR IDZ011-IDZ012.
OR...WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
TODAY FOR ORZ062-ORZ063-ORZ064.
WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
SATURDAY FOR ORZ062-ORZ063-ORZ064.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...JA
LONG TERM....LC
AVIATION.....LC
000
FXUS66 KPDT 100502 AAA
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1002 PM PDT THU OCT 9 2008
UPDATED AVIATION DISCUSSION
.UPDATE...SCATTERED SHOWERS CONTINUE ACROSS THE REGION THIS
EVENING...WITH SOME LOCATIONS IN GRANT COUNTY STARTING TO SEE SOME
LIGHT SNOW SHOWERS. THE HIGHEST PRECIPITATION AMOUNTS SEEN SO FAR IS
ONLY A COUPLE HUNDREDTHS AT LA GRANDE...MINAM AND MEACHAM
OREGON...THOUGH THE CASE RAWS IN NORTHERN GRANT COUNTY HAS REPORTED
ABOUT ONE TENTH OF AN INCH. EXPECT THE SHOWERS TO INCREASE IN
COVERAGE OVER CENTRAL AND NORTHEAST OREGON LATER TONIGHT AS THE LOW
PRESSURE SYSTEM CONTINUES TO MOVE FURTHER SOUTH OVER THE AREA. A
WINTER WEATHER ADVISORY IS IN EFFECT FOR TONIGHT FOR CENTRAL OREGON
AND THE JOHN DAY LOWLANDS AND HIGHLANDS. A FREEZE WARNING IS ALSO IN
EFFECT FOR TONIGHT FOR THE KITTITAS AND YAKIMA VALLEYS AS LOCATIONS
WILL REACH OR FALL BELOW THE FREEZING MARK BY TOMORROW MORNING.
CURRENT FORECAST LOOKS GOOD AND WILL UPDATE LATER TO REMOVE EVENING
WORDING. DMH
&&
.AVIATION...06Z TAFS...A WEATHER DISTURBANCE BRINGING SHOWERS ACROSS
CENTRAL AND NORTHEAST OREGON AND SOUTHEAST WASHINGTON WILL KEEP
SKIES PARTLY TO MOSTLY CLOUDY OVERNIGHT AND INTO TOMORROW MORNING.
CEILINGS WILL BE MOSTLY VFR OVER THE AREA. THE EXCEPTION IS KRDM
AND UNDER THE HEAVIER SNOW SHOWERS OVER THE HIGHER TERRAIN OF OREGON
WHERE CEILINGS WILL BE IN THE MVFR AND POSSIBLE LOCAL IFR
CATEGORIES. VISIBILITIES MAY DROP UNDER THE HEAVIEST SHOWERS BY
TOMORROW MORNING. WINDS WILL BECOME BREEZY...PRECIPITATION WILL
DECREASE AND SKIES WILL GRADUALLY CLEAR BY LATE MORNING AND EARLY
AFTERNOON TOMORROW. DMH
&&
.PREV DISCUSSION... /ISSUED 335 PM PDT THU OCT 9 2008/
UPDATE...FOR TONIGHT...COOL AIR WILL CONTINUE TO MOVE INTO THE
YAKIMA AND KITTITAS VALLEYS OVERNIGHT. NEAR OR BELOW FREEZING
TEMPERATURES WILL PERSIST FOR SEVERAL HOURS FRIDAY MORNING IN THOSE
VALLEYS...POSING A RISK TO TEMPERATURE SENSITIVE CROPS AND PLANTS.
A FREEZE WARNING IS NOW IN EFFECT FROM 2 AM TO 9 AM PDT
FRIDAY...REFER TO PRODUCT PDXNPWPDT FOR DETAILS.
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...A BROAD UPPER-LEVEL
TROUGH OVER THE PACIFIC NORTHWEST WILL BE REINFORCED BY A NORTHERLY
JET ALONG THE WEST SIDE OF THE TROUGH. A LIMITING FACTOR WITH THIS
SYSTEM IS A LACK OF DEEP MOISTURE...LESS THAN ONE-HALF INCH
PRECIPITABLE WATER ACCORDING TO UPPER-AIR BALLOON MEASUREMENTS AND
SATELLITE ESTIMATES. NONETHELESS...IMPULSES ALONG THE EAST SIDE OF
THE JET WILL BRING MODERATE FORCING FOR LIFT OVERNIGHT ACROSS
CENTRAL OREGON AND THE OCHOCO-JOHN DAY AREA. COMPUTER MODELS ARE IN
AGREEMENT AND RUN-TO-RUN CONSISTENCY IS ALSO GOOD FOR THIS
SCENARIO. FURTHERMORE...LOWERING SNOW LEVELS AND NORTHERLY UPSLOPE
FLOW WILL FAVOR SNOW ACCUMULATIONS ABOVE 3000 FEET ALONG NORTH
FACING SLOPES. AS SUCH...THE WINTER WEATHER ADVISORY WAS EXPANDED
AND NOW INCLUDES TERRAIN ABOVE 3000 FEET IN CENTRAL OREGON. THE
WINTER WEATHER ADVISORY FOR THE JOHN DAY-OCHOCO HIGHLANDS AND ABOVE
3000 FEET IN THE JOHN DAY BASIN ALSO REMAINS IN EFFECT FROM 10 PM
TONIGHT TO 10 AM FRIDAY MORNING. FOR ADDITIONAL INFORMATION SEE
PRODUCT PDXWSWPDT. BY FRIDAY AFTERNOON THE LOW PRESSURE SYSTEM WILL
HAVE MOVED FURTHER SOUTH INTO THE GREAT BASIN...LEADING TO A DRYING
TREND. HOWEVER SHOWERS ARE EXPECTED TO LINGER OVER THE OCHOCO
MOUNTAINS...GRANT COUNTY AND THE SOUTHERN BLUE MOUNTAINS. FRIDAY
NIGHT...SKIES WILL CLEAR ALLOWING FOR RAPID COOLING OF AN ALREADY
COOL AIR MASS. AS SUCH NEAR RECORD LOW TEMPERATURES ARE LIKELY
FRIDAY NIGHT AND PERHAPS AGAIN SATURDAY NIGHT. AFTERNOON
TEMPERATURES FRIDAY AND SATURDAY WILL BE 10 TO 15 DEGREES BELOW
NORMAL. 80
LONG TERM...SUNDAY THROUGH THURSDAY...NORTHERLY FLOW ON THE BACK
SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY. AN UPPER LEVEL RIDGE WILL MOVE FROM THE COAST
TO IDAHO SUNDAY NIGHT AND MONDAY. SUBSIDENCE FROM THE RIDGE WILL
KEEP SKIES MOSTLY CLEAR AND WINDS LIGHT ALLOWING GOOD RADIATIONAL
COOLING AT NIGHT. TUESDAY THROUGH THURSDAY WESTERLY FLOW WITH A
COUPLE OF WEAK FAST MOVING SYSTEMS WILL BE OVER THE PACIFIC
NORTHWEST. THESE SYSTEMS MAY TRIGGER A FEW SHOWERS IN THE MOUNTAINS.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
COONFIELD
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 35 55 32 56 / 50 20 10 0
ALW 37 57 33 59 / 40 10 10 0
PSC 36 59 30 60 / 20 10 0 0
YKM 31 56 28 58 / 20 0 0 0
HRI 36 57 30 58 / 30 10 10 0
ELN 30 56 29 59 / 20 0 0 0
RDM 30 48 25 51 / 70 50 20 0
LGD 32 49 29 51 / 50 40 20 0
GCD 31 49 27 52 / 60 60 20 10
DLS 37 60 32 63 / 30 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PDT FRIDAY FOR ORZ043-505-
506.
WA...FREEZE WARNING FROM 2 AM TO 9 AM PDT FRIDAY FOR WAZ026-027.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
84
000
FXUS66 KPQR 100409
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
900 PM PDT THU OCT 09 2008
.SYNOPSIS...COLD AIR IS SETTLING OVER THE AREA TONIGHT AS AN UPPER
LEVEL TROUGH PLACES THE REGION IN A NORTHWEST FLOW. SNOW LEVELS WILL
FALL TO AROUND 2500 FEET TONIGHT WITH SOME LIGHT SNOW ACCUMULATIONS
IN THE MOUNTAINS. SHOWERS WILL DECREASE TONIGHT. THE UPPER LEVEL
TROUGH WILL SHIFT EAST BEGINNING FRIDAY WITH NORTHERLY FLOW ALOFT
DEVELOPING AS A RIDGE OF HIGH PRESSURE ALOFT BUILDS OFFSHORE. THE
RIDGE WILL MOVE INLAND BY SUNDAY...BUT IS EXPECTED TO BREAK DOWN
EARLY NEXT WEEK...ALLOWING A PACIFIC COLD FRONT TO MOVE INLAND
BRUSHING THE NORTH.
&&
.SHORT TERM...A FEW SHOWERS CONTINUE THIS EVENING IN THE COOL AND
UNSTABLE NORTHWEST FLOW THAT FOLLOWS THE UPPER TROUGH SHIFTING EAST.
WITH THE FLOW ALOFT AND AT THE MID LEVELS MOSTLY BECOMING NORTH
NORTHWESTERLY THERE IS VERY LITTLE OROGRAPHIC ENHANCEMENT. AIRCRAFT
SOUNDING DATA SHOWS FREE AIR FREEZING LEVEL HAS LOWERED TO AROUND
3400 AT 03Z AND WILL CONTINUE TO LOWER A LITTLE MORE DURING THE
NIGHT. SNOW LEVEL OF AROUND 2500 FEET BUT WITH ONLY A FEW SHOWERS NOT
MUCH ACCUMULATION IN THE MOUNTAINS. TEMPERATURES ARE RUNNING UP TO 9
DEGREES COOLER TONIGHT...AT VANCOUVER...THAN LAST NIGHT AT THE SAME
TIME. EXPECT THE COOLEST NIGHT OF THE FALL TONIGHT AND COULD SEE SOME
TEMPS NEAR FREEZING EARLY TOMORROW MORNING IN THE OUTLYING AREAS AWAY
FROM THE CITY HEAT ISLANDS. EVEN COOLER FRIDAY NIGHT WITH GOOD
RADIATION CONDITIONS UNDER CLOUDLESS SKIES AND DRY AIR MASS.
SCHNEIDER
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
THE MODELS ARE VARYING BUT LOOKS LIKE THE RIDGE STAYS
STRONG ENOUGH TO KEEP MOST OF THE PRECIPITATION TO THE NORTH BRUSHING
THE NORTHWEST PART OF THE FORECAST AREA AT TIMES INTO THE EXTENDED.
&&
.AVIATION...SHOWERY NORTHWESTERLY FLOW WILL GRADUALLY DRY ALOFT
THROUGH THE EVENING AS AN UPPER LEVEL LOW OVER THE PACIFIC NW SHIFTS
SSE. GENERALLY VFR CONDITIONS ALL AREAS THROUGH 06Z...WITH
OCCASIONAL MVFR CONDITIONS IN HEAVIER SHOWERS. AT THE COAST...CIGS
MAY SAG TO MVFR BEFORE 06Z BUT AS CLOUD COVER FURTHER DISSIPATES
AFTER 09Z PATCHES OF IFR FOG WILL DEVELOP. INLAND MAY ALSO SEE IFR
CIGS AND FOG LATE TONIGHT AS WINDS SUBSIDE. EXPECT AREAS IFR CIGS IN
STRATUS ALONG WITH SOME FOG DEVELOPING AROUND THE WILLAMETTE
VALLEY...PARTICULARLY IN THE SOUTHERN VALLEY AFTER 11Z. LOW CLOUDS
WILL DISSIPATE WITH WIDESPREAD VFR RETURNING AROUND 19Z.
.KPDX AND APPROACHES...VFR THROUGH THE EVENING. AS WINDS SUBSIDE AND
SHOWERS DISSIPATE AREAS STRATUS AND PATCHY FOG MAY DEVELOP. MOST
LIKELY OUTCOME IS LOWER END MVFR CIG DEVELOPING AFTER 12Z. LOCAL
STUDY PUTS A VERY SLIGHT CHANCE OF IFR TOWARD DAYBREAK DUE TO FOG.
VFR WILL RETURN BETWEEN 18-19Z.
&&
.MARINE...STRONG HIGH PRESSURE OFFSHORE TONIGHT BUILDS INTO WATERS
FRIDAY. LOW PRESSURE WELL INLAND THIS EVENING WILL CONTINUES TO MOVE
SOUTHEAST OVERNIGHT AND FRIDAY. PRESSURE GRADIENTS WILL SLACKEN
CONSIDERABLY FRIDAY MORNING. SEAS BRIEFLY GO OVER 10 FEET TONIGHT
THEN SLIGHT BACK UNDER BY FRIDAY AFTERNOON. HIGH PRES OVER THE AREA
THROUGH THE WEEKEND SHOULD KEEP WINDS AND SEAS ON THE DOWNWARD TREND
THROUGH SUN AT LEAST. DK2
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO
FLORENCE THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO CASCADE HEAD THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CASCADE HEAD TO
FLORENCE THROUGH FRIDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THROUGH FRIDAY
MORNING
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
Http://weather.gov/portland
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KMFR 100405
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
905 PM PDT THU OCT 9 2008
.DISCUSSION...NORTHERLY 120KT JET ON THE BACK SIDE OF THE UPPER
LOW IS DIGGING DOWN THE NORTH OREGON NORTH COAST WITH AN INCREASE
IN SHOWER ACTIVITY SEEN THERE. SHOWERS OVER OUR AREA CONTINUE IN
UNUSUALLY COLD AND UNSTABLE NORTH FLOW...700 TEMPS AROUND -12C.
SEVERAL SITES MEASURING A FEW HUNDREDTHS OR MORE THIS EVENING IN
THE COOS-DOUGLAS REGION AND CASCADES WITH LESSER AMOUNTS SOUTH
INTO JACKSON COUNTY AND EAST SIDE AND CA. SNOW LEVELS HAVE DIPPED
TO NEAR 4000 FEET WITH ODOT CREWS ON THE CASCADE PASSES (HWYS
140...138...230...& 58) ALL REPORTING SOME LIGHT SNOW AND LOCAL
ICY/SLUSHY ROADS. 00Z MODELS SHOW LIGHT RAIN AND SNOW SHOWER
ACTIVITY CONTINUING INTO FRIDAY WITH THE WEST SIDE MOSTLY DRY BY
AFTERNOON. NO CHANGES NEEDED IN THE GRIDS THIS EVENING. STAVISH
&&
.PREV DISCUSSION... /ISSUED 244 PM PDT THU OCT 9 2008/
DISCUSSION...AN UPPER LEVEL TROUGH IS IN THE PROCESS OF MOVING
INTO THE AREA THIS AFTERNOON. AS EVIDENCED BY THE POPCORN CLOUD
FORMATION OVER THE WATER IN THE VISIBLE SATELLITE IMAGERY...MUCH
COLDER AIR WILL MOVE INTO THE CWA TONIGHT AND WILL REMAIN OVER THE
REGION THROUGH SUNDAY MORNING. AT THE SAME...THE LEFT EXIT REGION
OF THE JET WILL BE MOVING INTO WESTERN OREGON THIS EVENING AND
WE`LL REMAIN IN THE VICINITY OF THE LEFT EXIT REGION TONIGHT INTO
FRIDAY MORNING.
SHOWERS WILL BE ON THE INCREASE LATE THIS AFTERNOON ALONG AND WEST
OF THE CASCADES...THEN SPREADING EAST OF THE CASCADES OVERNIGHT
TONIGHT. SNOW LEVELS TONIGHT WILL LOWER TO AROUND 3500 FEET
TONIGHT AND WILL REMAIN BETWEEN 3500 AND 4000 FEET FRIDAY. HOWEVER
ANY SNOW ACCUMULATION WILL BE MAINLY CONFINED TO ABOVE 5000 FEET
DUE TO WARM GROUND AND ROAD TEMPERATURES. IN ADDITION...IT WILL BE
ONE OF THOSE SITUATIONS WHERE ANY ACCUMULATION WILL BE THE RESULT
OF A HEAVIER SHOWER DEVELOPING OR MOVING OVER A REGION WHICH COULD
LEAVE A TEMPORARY ACCUMULATION. ONCE THE SHOWERS DECREASE OR MOVE
AWAY...THEN THE SNOW SHOULD MELT.
SHOWERS WILL CONTINUE OVER MOST OF THE CWA INTO FRIDAY MORNING...THEN
THE FOCUS FOR SHOWERS WILL SHIFT ALONG AND EAST OF THE CASCADES
FRIDAY AFTERNOON WITH BOTH THE NAM AND GFS IN AGREEMENT SHOWING
500 MB TEMPS OF AROUND -30 C ALONG AND EAST OF THE CASCADES.
SHOWERS SHOULD END WEST OF THE CASCADES FRIDAY AFTERNOON...WITH
CLOUDS SLOWLY DECREASING.
THE LOW IS PROJECTED TO MOVE INTO NEVADA FRIDAY NIGHT FOLLOWED BY
A NORTH TO NORTHEAST FLOW ALOFT. THIS WILL ALLOW CLOUDS TO
CONTINUE TO DECREASE AND THIS ALONG WITH A COLD AIRMASS OVERHEAD
WILL ALLOW TEMPERATURES WEST OF THE CASCADES TO DROP TO NEAR OR
BELOW FREEZING OVER MOST LOCATIONS. FOR THIS REASON A FREEZE
WARNING HAS BEEN ISSUED FOR FRIDAY NIGHT AND SATURDAY NIGHT.
MEANWHILE SNOW SHOWERS WILL LINGER EAST OF THE CASCADES FRIDAY
EVENING...THEN WILL END WITH DECREASING CLOUDS AS THE UPPER LOW
CONTINUES TO MOVE SOUTH.
A NORTH TO NORTHEAST LOW WILL REMAIN OVER THE CWA OVER THE WEEKEND
AND AT THE SAME TIME THE RIDGE AXIS WILL SLOWLY SHIFT EAST TOWARDS
THE CWA. THE NET RESULT WILL BE DRY CONDITIONS. TEMPERATURES WILL
BE MILDER SATURDAY AND SUNDAY AFTERNOONS...BUT STILL COLD AT
NIGHT.
THE RIDGE WILL FLATTEN OUT SOME BY THE START OF NEXT WEEK AS WEAK
SHORTWAVE MOVES NORTH OF THE AREA...BUT ANY PRECIPITATION WILL
REMAIN NORTH OF THE CWA. BEYOND MONDAY...BOTH THE GFS AND ECMWF
SHOW A WEST TO NORTHWEST FLOW ALOFT WHICH WITH A FEW WEAK
DISTURBANCES PASSING BY TO THE NORTH. AT THIS TIME IT LOOKS LIKE
MOST OF NEXT WEEK WILL BE DRY WITH TEMPERATURES NEAR NORMAL.
&&
.AVIATION...SCT-BKN VFR DECKS AND SCT SHOWERS WILL CONTINUE INTO
FRIDAY. WET SNOW SHOWERS COULD MIX IN WITH RAIN SHOWERS AROUND
2000 TO 3000 FEET AGL TONIGHT AND FRIDAY. MTNS WILL OCCASIONALLY
BE OBSCURED THIS EVENING THROUGH FRIDAY. HOWEVER...VFR CONDITIONS
SHOULD BE THE PREDOMINATE CONDITION WITH LOCAL MVFR CONDITIONS
EXPECTED WEST OF THE CASCADES FRIDAY. THERE SHOULD NOT BE ANY
VISIBILITY ISSUES TONIGHT AND FRIDAY BUT THEY COULD DROP BELOW 5
MILES IN LOCATIONS THAT ARE UNDER A HEAVIER SHOWER.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
CA...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR CAZ080-CAZ081-
CAZ082.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR CAZ080-CAZ081-
CAZ082.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM
PDT SATURDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PDT SATURDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
000
FXUS65 KBOI 100340
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
940 PM MDT THU OCT 9 2008
.DISCUSSION...MAJOR STORM SYSTEM AND BIG CHANGE EVENT CONTINUES TO
EVOLVE AND IS JUST IN THE FORMATIVE STAGE. FIRST BAND OF CONVECTIVE
RAIN AND SNOW SHOWERS NOW MOVING THROUGH EASTERN OREGON AND THE
LOWER TREASURE VALLEY OF SOUTHWEST IDAHO. MEANWHILE...SATELLITE
IMAGES AND MODEL PROGS SHOWING A LARGE COLD CORED UPPER LOW CENTER
CLOSING OFF OVER SOUTHWEST IDAHO BETWEEN 06Z AND 12Z. IT APPEARS
THE FIRST WAVE OF SHOWERS WILL IMPACT HIGHER TERRAIN OF SOUTHEAST
OREGON AND MOUNTAINS NORTH OF BOISE. THUS...THIS IS THE REASONING
BEHIND THE FAIRLY LOW POPS FOR THE OVERNIGHT PERIOD. NEW 00Z NAM
TAKES THE UPPER LOW SOUTHWARD INTO CENTRAL NEVADA FRIDAY BEFORE
FINALLY RELEASING IT BACK NORTHEAST SATURDAY AND SUNDAY. WINDS WILL
BE A BIG ISSUE WITH THE DEVELOPING STORM AND MAY NOT FULLY INTENSIFY
UNTIL UPPER LOW MOVES SOUTH AND EAST OF THE AREA. WINDS FOR SATURDAY
AND SUNDAY APPEAR TO BE THE STRONGEST WHILE FRIDAY IS A BIT MORE
TRICKY SINCE WINDS ALOFT NOT ALIGNED FROM SURFACE TO ALOFT WHILE LOW
IS IN THE INITIAL DEVELOPING STAGES. MULTIPLE HIGHLIGHTS APPEAR ON
TARGET BUT MID CREW IN COORDINATION WITH ADJACENT OFFICES WILL NEED
TO MAKE FINAL ADJUSTMENTS BEFORE EVENT GETS INTO FULL SWING FRIDAY
THROUGH SUNDAY.
&&
.AVIATION...AREAS OF VFR CONDITIONS TONIGHT WILL BECOMING WIDESPREAD
MVFR CONDITIONS OVERNIGHT WITH MAJOR WINTER STORM MOVING INTO THE
REGION. GUSTY WINDS AND MODERATE SNOW SHOWERS WILL BE THE MAIN
AVIATION CONCERNS OVERNIGHT THROUGH SATURDAY. MODERATE NORTHWEST
SURFACE WINDS WILL DIMINISH SOME TONIGHT THEN INCREASE MOST AREAS BY
FRIDAY AFTERNOON. SCATTERED SNOW SHOWERS WILL CONTINUE TO MOVE IN
FROM NORTHWEST THIS EVENING. EXPECT VFR IN MOST VALLEYS BUT MVFR TO
IFR CONDITIONS IN MOUNTAINS AND MOUNTAIN VALLEYS WITH SHOWERS
THROUGH FRIDAY NIGHT. WINTER CONDITIONS REMAINING OVER THE AREA
FRIDAY...SLOW IMPROVING FROM NORTHWEST BEGINNING SATURDAY.
&&
.PREV DISCUSSION...TONIGHT THROUGH SATURDAY...IMPRESSIVE EARLY
SEASON WINTER-LIKE STORM TAKING SHAPE OVER THE REGION. EXPECTING
STRONG NORTHWEST WINDS OF 25 TO 40 MPH WITH GUSTS TO 55 MPH ALONG A
CORRIDOR FROM ONTARIO TO BAKER...BOTH FRIDAY AND SATURDAY AFTERNOON.
WIND ADVISORIES ARE ALREADY IN EFFECT...PLEASE REFER TO BOINPWBOI
FOR THE DETAILS. RAIN AND SNOW SHOWERS WILL SPREAD ACROSS THE AREA
FROM THE NORTHWEST OVERNIGHT AND FRIDAY...WITH SNOW LEVELS FALLING
TO NEAR VALLEY FLOORS BY EARLY FRIDAY MORNING. UPPER LOW WILL DIVE
SOUTHEAST ON FRIDAY...THEN TURN BACK TO THE NORTHEAST FRIDAY NIGHT
AND SATURDAY WITH MOISTURE WRAPPING AROUND THE LOW AND INTO PORTIONS
OF SOUTHWEST IDAHO. THE LOW TRACK IS FAVORABLE FOR SIGNIFICANT SNOWS
IN THE WESTERN MAGIC VALLEY AND SOUTHERN TWIN FALLS COUNTY. WILL
ISSUE A WINTER STORM WATCH FOR THOSE AREAS FROM MIDNIGHT SATURDAY TO
MIDNIGHT SUNDAY. FOR THE TREASURE VALLEY INCLUDING BOISE...THE BEST
OPPORTUNITY FOR RAIN/SNOW COMES FRIDAY. IT APPEARS THAT THE AMOUNTS
WILL BE LIGHT...BUT A DUSTING OF SNOW ON GRASSY AREAS IS POSSIBLE.
STILL LOOKING FOR A COUPLE INCHES ABOVE 4000 FEET AND 2 TO 5 INCHES
ABOVE 6000 FEET.
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE STORM WILL BE
HEADING EAST OUT OF THE AREA SUNDAY WITH IMPROVING CONDITIONS FROM
THE NORTHWEST. BY MONDAY THE STORM WILL BE OUT OF THE AREA.
TEMPERATURES WILL BE COOL SUNDAY WITH SLIGHT WARMING MONDAY. A WEAK
TROF MOVES OVER THE AREA WEDNESDAY WITH A CHANCE OF PRECIP OVER
NORTHERN AREA. THE TROF AND PREDOMINATELY WESTERLY FLOW ALOFT WILL
INHIBIT MUCH WARMUP OVER THE AREA...THUS TEMPERATURES REMAINING
ABOUT 10 DEGREES BELOW NORMAL LATTER HALF OF NEXT WEEK.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER STORM WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY
EVENING FOR IDZ016-IDZ030.
WIND ADVISORY FROM 12 PM TO 9 PM MDT FRIDAY FOR IDZ011-IDZ012.
WIND ADVISORY FROM 12 PM TO 9 PM MDT SATURDAY FOR IDZ011-IDZ012.
OR...WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
FRIDAY FOR ORZ062-ORZ063-ORZ064.
WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
SATURDAY FOR ORZ062-ORZ063-ORZ064.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...GS
PREV DISCUSSION...BW
LONG TERM....PF/DD
AVIATION.....JS
000
FXUS66 KPDT 100307
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
807 PM PDT THU OCT 9 2008
.UPDATE...SCATTERED SHOWERS CONTINUE ACROSS THE REGION THIS
EVENING...WITH SOME LOCATIONS IN GRANT COUNTY STARTING TO SEE SOME
LIGHT SNOW SHOWERS. THE HIGHEST PRECIPITATION AMOUNTS SEEN SO FAR IS
ONLY A COUPLE HUNDREDTHS AT LA GRANDE...MINAM AND MEACHAM
OREGON...THOUGH THE CASE RAWS IN NORTHERN GRANT COUNTY HAS REPORTED
ABOUT ONE TENTH OF AN INCH. EXPECT THE SHOWERS TO INCREASE IN
COVERAGE OVER CENTRAL AND NORTHEAST OREGON LATER TONIGHT AS THE LOW
PRESSURE SYSTEM CONTINUES TO MOVE FURTHER SOUTH OVER THE AREA. A
WINTER WEATHER ADVISORY IS IN EFFECT FOR TONIGHT FOR CENTRAL OREGON
AND THE JOHN DAY LOWLANDS AND HIGHLANDS. A FREEZE WARNING IS ALSO IN
EFFECT FOR TONIGHT FOR THE KITTITAS AND YAKIMA VALLEYS AS LOCATIONS
WILL REACH OR FALL BELOW THE FREEZING MARK BY TOMORROW MORNING.
CURRENT FORECAST LOOKS GOOD AND WILL UPDATE LATER TO REMOVE EVENING
WORDING. DMH
&&
.PREV DISCUSSION... /ISSUED 335 PM PDT THU OCT 9 2008/
UPDATE...FOR TONIGHT...COOL AIR WILL CONTINUE TO MOVE INTO THE
YAKIMA AND KITTITAS VALLEYS OVERNIGHT. NEAR OR BELOW FREEZING
TEMPERATURES WILL PERSIST FOR SEVERAL HOURS FRIDAY MORNING IN THOSE
VALLEYS...POSING A RISK TO TEMPERATURE SENSITIVE CROPS AND PLANTS.
A FREEZE WARNING IS NOW IN EFFECT FROM 2 AM TO 9 AM PDT
FRIDAY...REFER TO PRODUCT PDXNPWPDT FOR DETAILS.
SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...A BROAD UPPER-LEVEL
TROUGH OVER THE PACIFIC NORTHWEST WILL BE REINFORCED BY A NORTHERLY
JET ALONG THE WEST SIDE OF THE TROUGH. A LIMITING FACTOR WITH THIS
SYSTEM IS A LACK OF DEEP MOISTURE...LESS THAN ONE-HALF INCH
PRECIPITABLE WATER ACCORDING TO UPPER-AIR BALLOON MEASUREMENTS AND
SATELLITE ESTIMATES. NONETHELESS...IMPULSES ALONG THE EAST SIDE OF
THE JET WILL BRING MODERATE FORCING FOR LIFT OVERNIGHT ACROSS
CENTRAL OREGON AND THE OCHOCO-JOHN DAY AREA. COMPUTER MODELS ARE IN
AGREEMENT AND RUN-TO-RUN CONSISTENCY IS ALSO GOOD FOR THIS
SCENARIO. FURTHERMORE...LOWERING SNOW LEVELS AND NORTHERLY UPSLOPE
FLOW WILL FAVOR SNOW ACCUMULATIONS ABOVE 3000 FEET ALONG NORTH
FACING SLOPES. AS SUCH...THE WINTER WEATHER ADVISORY WAS EXPANDED
AND NOW INCLUDES TERRAIN ABOVE 3000 FEET IN CENTRAL OREGON. THE
WINTER WEATHER ADVISORY FOR THE JOHN DAY-OCHOCO HIGHLANDS AND ABOVE
3000 FEET IN THE JOHN DAY BASIN ALSO REMAINS IN EFFECT FROM 10 PM
TONIGHT TO 10 AM FRIDAY MORNING. FOR ADDITIONAL INFORMATION SEE
PRODUCT PDXWSWPDT. BY FRIDAY AFTERNOON THE LOW PRESSURE SYSTEM WILL
HAVE MOVED FURTHER SOUTH INTO THE GREAT BASIN...LEADING TO A DRYING
TREND. HOWEVER SHOWERS ARE EXPECTED TO LINGER OVER THE OCHOCO
MOUNTAINS...GRANT COUNTY AND THE SOUTHERN BLUE MOUNTAINS. FRIDAY
NIGHT...SKIES WILL CLEAR ALLOWING FOR RAPID COOLING OF AN ALREADY
COOL AIR MASS. AS SUCH NEAR RECORD LOW TEMPERATURES ARE LIKELY
FRIDAY NIGHT AND PERHAPS AGAIN SATURDAY NIGHT. AFTERNOON
TEMPERATURES FRIDAY AND SATURDAY WILL BE 10 TO 15 DEGREES BELOW
NORMAL. 80
LONG TERM...SUNDAY THROUGH THURSDAY...NORTHERLY FLOW ON THE BACK
SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY. AN UPPER LEVEL RIDGE WILL MOVE FROM THE COAST
TO IDAHO SUNDAY NIGHT AND MONDAY. SUBSIDENCE FROM THE RIDGE WILL
KEEP SKIES MOSTLY CLEAR AND WINDS LIGHT ALLOWING GOOD RADIATIONAL
COOLING AT NIGHT. TUESDAY THROUGH THURSDAY WESTERLY FLOW WITH A
COUPLE OF WEAK FAST MOVING SYSTEMS WILL BE OVER THE PACIFIC
NORTHWEST. THESE SYSTEMS MAY TRIGGER A FEW SHOWERS IN THE MOUNTAINS.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
COONFIELD
AVIATION...0Z TAFS...MID AND HIGH CLOUDS WILL INCREASE TONIGHT WITH
AN APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL BE
PREDOMINATELY VFR TONIGHT EXCEPT AT KRDM. LOCAL MVFR OR IFR CEILINGS
MAY DEVELOP TONIGHT NEAR RAIN AND MOUNTAIN SNOW SHOWERS. AT KRDM
PREVAILING CEILINGS WILL GRADUALLY DROP TO 25-35 KFT WITH CEILINGS
AS LOW AS 15 KFT NEAR SNOW SHOWERS. VISIBILITIES MAY DROP TO MVFR OR
IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT..ESPECIALLY NEAR KRDM. WINDS WILL REMAIN BREEZY IN THE
EASTERN COLUMBIA GORGE WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 35 55 32 56 / 50 20 10 0
ALW 37 57 33 59 / 40 10 10 0
PSC 36 59 30 60 / 20 10 0 0
YKM 31 56 28 58 / 20 0 0 0
HRI 36 57 30 58 / 30 10 10 0
ELN 30 56 29 59 / 20 0 0 0
RDM 30 48 25 51 / 70 50 20 0
LGD 32 49 29 51 / 50 40 20 0
GCD 31 49 27 52 / 60 60 20 10
DLS 37 60 32 63 / 30 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 AM PDT FRIDAY FOR ORZ043-505-
506.
WA...FREEZE WARNING FROM 2 AM TO 9 AM PDT FRIDAY FOR WAZ026-027.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
84
000
FXUS66 KPDT 092234 AAB
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
335 PM PDT THU OCT 9 2008
UPDATED AVIATION DISCUSSION
.UPDATE...FOR TONIGHT...COOL AIR WILL CONTINUE TO MOVE INTO THE
YAKIMA AND KITTITAS VALLEYS OVERNIGHT. NEAR OR BELOW FREEZING
TEMPERATURES WILL PERSIST FOR SEVERAL HOURS FRIDAY MORNING IN THOSE
VALLEYS...POSING A RISK TO TEMPERATURE SENSITIVE CROPS AND PLANTS.
A FREEZE WARNING IS NOW IN EFFECT FROM 2 AM TO 9 AM PDT
FRIDAY...REFER TO PRODUCT PDXNPWPDT FOR DETAILS.
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...A BROAD UPPER-LEVEL
TROUGH OVER THE PACIFIC NORTHWEST WILL BE REINFORCED BY A NORTHERLY
JET ALONG THE WEST SIDE OF THE TROUGH. A LIMITING FACTOR WITH THIS
SYSTEM IS A LACK OF DEEP MOISTURE...LESS THAN ONE-HALF INCH
PRECIPITABLE WATER ACCORDING TO UPPER-AIR BALLOON MEASUREMENTS AND
SATELLITE ESTIMATES. NONETHELESS...IMPULSES ALONG THE EAST SIDE OF
THE JET WILL BRING MODERATE FORCING FOR LIFT OVERNIGHT ACROSS
CENTRAL OREGON AND THE OCHOCO-JOHN DAY AREA. COMPUTER MODELS ARE IN
AGREEMENT AND RUN-TO-RUN CONSISTENCY IS ALSO GOOD FOR THIS
SCENARIO. FURTHERMORE...LOWERING SNOW LEVELS AND NORTHERLY UPSLOPE
FLOW WILL FAVOR SNOW ACCUMULATIONS ABOVE 3000 FEET ALONG NORTH
FACING SLOPES. AS SUCH...THE WINTER WEATHER ADVISORY WAS EXPANDED
AND NOW INCLUDES TERRAIN ABOVE 3000 FEET IN CENTRAL OREGON. THE
WINTER WEATHER ADVISORY FOR THE JOHN DAY-OCHOCO HIGHLANDS AND ABOVE
3000 FEET IN THE JOHN DAY BASIN ALSO REMAINS IN EFFECT FROM 10 PM
TONIGHT TO 10 AM FRIDAY MORNING. FOR ADDITIONAL INFORMATION SEE
PRODUCT PDXWSWPDT. BY FRIDAY AFTERNOON THE LOW PRESSURE SYSTEM WILL
HAVE MOVED FURTHER SOUTH INTO THE GREAT BASIN...LEADING TO A DRYING
TREND. HOWEVER SHOWERS ARE EXPECTED TO LINGER OVER THE OCHOCO
MOUNTAINS...GRANT COUNTY AND THE SOUTHERN BLUE MOUNTAINS. FRIDAY
NIGHT...SKIES WILL CLEAR ALLOWING FOR RAPID COOLING OF AN ALREADY
COOL AIR MASS. AS SUCH NEAR RECORD LOW TEMPERATURES ARE LIKELY
FRIDAY NIGHT AND PERHAPS AGAIN SATURDAY NIGHT. AFTERNOON
TEMPERATURES FRIDAY AND SATURDAY WILL BE 10 TO 15 DEGREES BELOW
NORMAL. 80
.LONG TERM...SUNDAY THROUGH THURSDAY...NORTHERLY FLOW ON THE BACK
SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY. AN UPPER LEVEL RIDGE WILL MOVE FROM THE COAST
TO IDAHO SUNDAY NIGHT AND MONDAY. SUBSIDENCE FROM THE RIDGE WILL
KEEP SKIES MOSTLY CLEAR AND WINDS LIGHT ALLOWING GOOD RADIATIONAL
COOLING AT NIGHT. TUESDAY THROUGH THURSDAY WESTERLY FLOW WITH A
COUPLE OF WEAK FAST MOVING SYSTEMS WILL BE OVER THE PACIFIC
NORTHWEST. THESE SYSTEMS MAY TRIGGER A FEW SHOWERS IN THE MOUNTAINS.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
COONFIELD
&&
.AVIATION...0Z TAFS...MID AND HIGH CLOUDS WILL INCREASE TONIGHT WITH
AN APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL BE
PREDOMINATELY VFR TONIGHT EXCEPT AT KRDM. LOCAL MVFR OR IFR CEILINGS
MAY DEVELOP TONIGHT NEAR RAIN AND MOUNTAIN SNOW SHOWERS. AT KRDM
PREVAILING CEILINGS WILL GRADUALLY DROP TO 25-35 KFT WITH CEILINGS
AS LOW AS 15 KFT NEAR SNOW SHOWERS. VISIBILITIES MAY DROP TO MVFR OR
IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT..ESPECIALLY NEAR KRDM. WINDS WILL REMAIN BREEZY IN THE
EASTERN COLUMBIA GORGE WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 35 55 32 56 / 50 20 10 0
ALW 37 57 33 59 / 40 10 10 0
PSC 36 59 30 60 / 20 10 0 0
YKM 31 56 28 58 / 20 0 0 0
HRI 36 57 30 58 / 30 10 10 0
ELN 30 56 29 59 / 20 0 0 0
RDM 30 48 25 51 / 70 50 20 0
LGD 32 49 29 51 / 50 40 20 0
GCD 31 49 27 52 / 60 60 20 10
DLS 37 60 32 63 / 30 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ043-505-506.
WA...FREEZE WARNING FROM 2 AM TO 9 AM PDT FRIDAY FOR WAZ026-027.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80/76/76
000
FXUS66 KPDT 092203 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
300 PM PDT THU OCT 9 2008
UPDATED FOR FREEZE WARNING TONIGHT FOR YAKIMA AND KITTITAS VALLEYS
.UPDATE...FOR TONIGHT...COOL AIR WILL CONTINUE TO MOVE INTO THE
YAKIMA AND KITTITAS VALLEYS OVERNIGHT. NEAR OR BELOW FREEZING
TEMPERATURES WILL PERSIST FOR SEVERAL HOURS FRIDAY MORNING IN THOSE
VALLEYS...POSING A RISK TO TEMPERATURE SENSITIVE CROPS AND PLANTS.
A FREEZE WARNING IS NOW IN EFFECT FROM 2 AM TO 9 AM PDT
FRIDAY...REFER TO PRODUCT PDXNPWPDT FOR DETAILS.
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT...A BROAD UPPER-LEVEL
TROUGH OVER THE PACIFIC NORTHWEST WILL BE REINFORCED BY A NORTHERLY
JET ALONG THE WEST SIDE OF THE TROUGH. A LIMITING FACTOR WITH THIS
SYSTEM IS A LACK OF DEEP MOISTURE...LESS THAN ONE-HALF INCH
PRECIPITABLE WATER ACCORDING TO UPPER-AIR BALLOON MEASUREMENTS AND
SATELLITE ESTIMATES. NONETHELESS...IMPULSES ALONG THE EAST SIDE OF
THE JET WILL BRING MODERATE FORCING FOR LIFT OVERNIGHT ACROSS
CENTRAL OREGON AND THE OCHOCO-JOHN DAY AREA. COMPUTER MODELS ARE IN
AGREEMENT AND RUN-TO-RUN CONSISTENCY IS ALSO GOOD FOR THIS
SCENARIO. FURTHERMORE...LOWERING SNOW LEVELS AND NORTHERLY UPSLOPE
FLOW WILL FAVOR SNOW ACCUMULATIONS ABOVE 3000 FEET ALONG NORTH
FACING SLOPES. AS SUCH...THE WINTER WEATHER ADVISORY WAS EXPANDED
AND NOW INCLUDES TERRAIN ABOVE 3000 FEET IN CENTRAL OREGON. THE
WINTER WEATHER ADVISORY FOR THE JOHN DAY-OCHOCO HIGHLANDS AND ABOVE
3000 FEET IN THE JOHN DAY BASIN ALSO REMAINS IN EFFECT FROM 10 PM
TONIGHT TO 10 AM FRIDAY MORNING. FOR ADDITIONAL INFORMATION SEE
PRODUCT PDXWSWPDT. BY FRIDAY AFTERNOON THE LOW PRESSURE SYSTEM WILL
HAVE MOVED FURTHER SOUTH INTO THE GREAT BASIN...LEADING TO A DRYING
TREND. HOWEVER SHOWERS ARE EXPECTED TO LINGER OVER THE OCHOCO
MOUNTAINS...GRANT COUNTY AND THE SOUTHERN BLUE MOUNTAINS. FRIDAY
NIGHT...SKIES WILL CLEAR ALLOWING FOR RAPID COOLING OF AN ALREADY
COOL AIR MASS. AS SUCH NEAR RECORD LOW TEMPERATURES ARE LIKELY
FRIDAY NIGHT AND PERHAPS AGAIN SATURDAY NIGHT. AFTERNOON
TEMPERATURES FRIDAY AND SATURDAY WILL BE 10 TO 15 DEGREES BELOW
NORMAL. 80
.LONG TERM...SUNDAY THROUGH THURSDAY...NORTHERLY FLOW ON THE BACK
SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY. AN UPPER LEVEL RIDGE WILL MOVE FROM THE COAST
TO IDAHO SUNDAY NIGHT AND MONDAY. SUBSIDENCE FROM THE RIDGE WILL
KEEP SKIES MOSTLY CLEAR AND WINDS LIGHT ALLOWING GOOD RADIATIONAL
COOLING AT NIGHT. TUESDAY THROUGH THURSDAY WESTERLY FLOW WITH A
COUPLE OF WEAK FAST MOVING SYSTEMS WILL BE OVER THE PACIFIC
NORTHWEST. THESE SYSTEMS MAY TRIGGER A FEW SHOWERS IN THE MOUNTAINS.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
COONFIELD
&&
.AVIATION...18Z TAFS...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH
AN APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL
REMAIN ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER
TONIGHT. LOCAL MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN
AND MOUNTAIN SNOW SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM.
VISIBILITIES WILL REMAIN ABOVE 6 NM THROUGH THE DAY BUT MAY DROP TO
MVFR OR IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT. WINDS ARE ALSO EXPECTED TO INCREASE TODAY AND TONIGHT IN
THE EASTERN COLUMBIA GORGE WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 35 55 32 56 / 50 20 10 0
ALW 37 57 33 59 / 40 10 10 0
PSC 36 59 30 60 / 20 10 0 0
YKM 31 56 28 58 / 20 0 0 0
HRI 36 57 30 58 / 30 10 10 0
ELN 30 56 29 59 / 20 0 0 0
RDM 30 48 25 51 / 70 50 20 0
LGD 32 49 29 51 / 50 40 20 0
GCD 31 49 27 52 / 60 60 20 10
DLS 37 60 32 63 / 30 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ043-505-506.
WA...FREEZE WARNING FROM 2 AM TO 9 AM PDT FRIDAY FOR WAZ026-027.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80/76/76
000
FXUS66 KMFR 092144
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
244 PM PDT THU OCT 9 2008
.DISCUSSION...AN UPPER LEVEL TROUGH IS IN THE PROCESS OF MOVING
INTO THE AREA THIS AFTERNOON. AS EVIDENCED BY THE POPCORN CLOUD
FORMATION OVER THE WATER IN THE VISIBLE SATELLITE IMAGERY...MUCH
COLDER AIR WILL MOVE INTO THE CWA TONIGHT AND WILL REMAIN OVER THE
REGION THROUGH SUNDAY MORNING. AT THE SAME...THE LEFT EXIT REGION
OF THE JET WILL BE MOVING INTO WESTERN OREGON THIS EVENING AND
WE`LL REMAIN IN THE VICINITY OF THE LEFT EXIT REGION TONIGHT INTO
FRIDAY MORNING.
SHOWERS WILL BE ON THE INCREASE LATE THIS AFTERNOON ALONG AND WEST
OF THE CASCADES...THEN SPREADING EAST OF THE CASCADES OVERNIGHT
TONIGHT. SNOW LEVELS TONIGHT WILL LOWER TO AROUND 3500 FEET
TONIGHT AND WILL REMAIN BETWEEN 3500 AND 4000 FEET FRIDAY. HOWEVER
ANY SNOW ACCUMULATION WILL BE MAINLY CONFINED TO ABOVE 5000 FEET
DUE TO WARM GROUND AND ROAD TEMPERATURES. IN ADDITION...IT WILL BE
ONE OF THOSE SITUATIONS WHERE ANY ACCUMULATION WILL BE THE RESULT
OF A HEAVIER SHOWER DEVELOPING OR MOVING OVER A REGION WHICH COULD
LEAVE A TEMPORARY ACCUMULATION. ONCE THE SHOWERS DECREASE OR MOVE
AWAY...THEN THE SNOW SHOULD MELT.
SHOWERS WILL CONTINUE OVER MOST OF THE CWA INTO FRIDAY MORNING...THEN
THE FOCUS FOR SHOWERS WILL SHIFT ALONG AND EAST OF THE CASCADES
FRIDAY AFTERNOON WITH BOTH THE NAM AND GFS IN AGREEMENT SHOWING
500 MB TEMPS OF AROUND -30 C ALONG AND EAST OF THE CASCADES.
SHOWERS SHOULD END WEST OF THE CASCADES FRIDAY AFTERNOON...WITH
CLOUDS SLOWLY DECREASING.
THE LOW IS PROJECTED TO MOVE INTO NEVADA FRIDAY NIGHT FOLLOWED BY
A NORTH TO NORTHEAST FLOW ALOFT. THIS WILL ALLOW CLOUDS TO
CONTINUE TO DECREASE AND THIS ALONG WITH A COLD AIRMASS OVERHEAD
WILL ALLOW TEMPERATURES WEST OF THE CASCADES TO DROP TO NEAR OR
BELOW FREEZING OVER MOST LOCATIONS. FOR THIS REASON A FREEZE
WARNING HAS BEEN ISSUED FOR FRIDAY NIGHT AND SATURDAY NIGHT.
MEANWHILE SNOW SHOWERS WILL LINGER EAST OF THE CASCADES FRIDAY
EVENING...THEN WILL END WITH DECREASING CLOUDS AS THE UPPER LOW
CONTINUES TO MOVE SOUTH.
A NORTH TO NORTHEAST LOW WILL REMAIN OVER THE CWA OVER THE WEEKEND
AND AT THE SAME TIME THE RIDGE AXIS WILL SLOWLY SHIFT EAST TOWARDS
THE CWA. THE NET RESULT WILL BE DRY CONDITIONS. TEMPERATURES WILL
BE MILDER SATURDAY AND SUNDAY AFTERNOONS...BUT STILL COLD AT
NIGHT.
THE RIDGE WILL FLATTEN OUT SOME BY THE START OF NEXT WEEK AS WEAK
SHORTWAVE MOVES NORTH OF THE AREA...BUT ANY PRECIPITATION WILL
REMAIN NORTH OF THE CWA. BEYOND MONDAY...BOTH THE GFS AND ECMWF
SHOW A WEST TO NORTHWEST FLOW ALOFT WHICH WITH A FEW WEAK
DISTURBANCES PASSING BY TO THE NORTH. AT THIS TIME IT LOOKS LIKE
MOST OF NEXT WEEK WILL BE DRY WITH TEMPERATURES NEAR NORMAL.
&&
.AVIATION...BKN TO OVC SKIES ARE EXPECTED THE REST OF THE
AFTERNOON AND TONIGHT AS AN UPPER LEVEL TROUGH MOVES INTO THE
AREA. SHOWERS WILL INCREASE LATE THIS AFTERNOON AND WILL CONTINUE
INTO FRIDAY. WET SNOW SHOWERS COULD MIX IN WITH RAIN SHOWERS
AROUND 2000 TO 3000 FEET AGL TONIGHT AND FRIDAY. MTNS WILL
OCCASIONALLY BE OBSCURED THIS EVENING THROUGH FRIDAY. HOWEVER...VFR
CONDITIONS SHOULD BE THE PREDOMINATE CONDITION WITH LOCAL MVFR
CONDITIONS EXPECTED WEST OF THE CASCADES FRIDAY. THERE SHOULD
NOT BE ANY VISIBILITY ISSUES TONIGHT AND FRIDAY BUT THEY COULD DROP
BELOW 5 MILES IN LOCATIONS THAT ARE UNDER A HEAVIER SHOWER.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR ORZ021-ORZ023-
ORZ024-ORZ025-ORZ026.
CA...FREEZE WARNING FROM 1 AM TO 9 AM PDT SATURDAY FOR CAZ080-CAZ081-
CAZ082.
FREEZE WARNING FROM 1 AM TO 9 AM PDT SUNDAY FOR CAZ080-CAZ081-
CAZ082.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM
PDT SATURDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PDT SATURDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
PETRUCELLI
000
FXUS66 KPQR 092117
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
300 PM PDT THU OCT 09 2008
.SYNOPSIS...A COLD TROUGH OF LOW PRESSURE FROM THE GULF OF ALASKA IS
DROPPING SOUTHEAST INTO THE PACIFIC NORTHWEST THIS AFTERNOON USHERING
IN A MUCH COOLER AIR MASS WITH SNOW LEVELS FALLING TO AROUND 3000
FEET TODAY AND NEAR 2500 TONIGHT SOME LIGHT SNOW ACCUMULATIONS IN THE
MOUNTAINS. SHOWERS ARE ROTATING INLAND WITH SOME ENHANCEMENT ALONG
THE COAST RANGE AND CASCADES. THE UPPER LEVEL TROUGH WILL SHIFT EAST
THIS WEEKEND WITH NORTHERLY FLOW ALOFT DEVELOPING AS A RIDGE OF HIGH
PRESSURE ALOFT BUILDS OFFSHORE. THE RIDGE WILL MOVE INLAND BY
SUNDAY...BUT IS EXPECTED TO BREAK DOWN EARLY NEXT WEEK...ALLOWING A
PACIFIC COLD FRONT TO MOVE INLAND BRUSHING THE NORTH.
&&
.SHORT TERM...A LARGE COOL UPPER LEVEL TROUGH IS SETTLING SOUTH OVER
THE PACIFIC NORTHWEST THIS AFTERNOON AND A SHORTWAVE WITHIN THE
TROUGH IS ENHANCING SHOWERS OVER THE FORECAST AREA AS IS OROGRAPHIC
LIFT ON THE WEST SLOPES OF RANGES. LAPSE RATES ARE STEEP WITH
LIFTED INDEX JUST AROUND ZERO FOR POSSIBILITY OF THUNDERSTORMS OVER
THE NORTHERN ZONES FOR THE AFTERNOON AND EARLY EVENING THE MODEL
1000/700 MILLIBAR THICKNESS SUPPORTS SNOW LEVELS BELOW PASS LEVELS
THIS EVENING AND TONIGHT FALLING DOWN TO NEAR 2500 FEET BY LATER
TONIGHT AS THE COLD AIR CONTINUES TO SPREAD INTO THE FORECAST AREA.
THERE APPEARS TO BE SUFFICIENT PRECIPITATION WITH THE SYSTEM BRIEFLY
ENHANCED BY AN OROGRAPHICALLY FAVORED NW FLOW...TO POSSIBLY YIELD A
COUPLE INCHES OF SNOW IN THE CASCADES...SO A SPECIAL WEATHER
STATEMENT ADDRESSES THAT. SINCE THIS WEATHER SYSTEM ORIGINATED AT
MUCH HIGHER LATITUDES...IT WILL BE THE COLDEST SYSTEM TO MOVE INTO
THE PACIFIC NORTHWEST SO FAR THIS FALL SEASON. MODELS ARE IN
REASONABLY GOOD AGREEMENT IN SHOWING THE DEVELOPING WEST COAST TROUGH
TO BE SLOW TO PULL OFF TO THE EAST FRI AND SAT AS HIGH PRESSURE
DEVELOPS OFFSHORE. SOME LINGERING SHOWERS ARE EXPECTED IN THE
CASCADES THROUGH FRI EVENING. AFTERNOON TEMPERATURES WILL
SLOWLY REBOUND FRI AND SAT...BUT IT COULD BE A FROSTY NIGHT FRIDAY
NIGHT A POSSIBLY SATURDAY NIGHT AS THE COOL DRY AIR MASS RADIATES
WELL UNDER CLEARING SKIES. WILLSON
.LONG TERM...THE MODELS ARE VARYING BUT LOOKS LIKE THE RIDGE STAYS
STRONG ENOUGH TO KEEP MOST OF THE PRECIPITATION TO THE NORTH BRUSHING
THE NORTHWEST PART OF THE FORECAST AREA AT TIMES INTO THE EXTENDED.
&&
.AVIATION...A COLD UPPER OFF THE WASHINGTON COAST MOVES OVER
NORTHWEST OREGON THIS EVENING THEN MOVES TO NORTHERN CALIFORNIA
FRIDAY MORNING. LOW PRESSURE CONTINUES MOVING SOUTH FRIDAY AS HIGH
PRESSURE BUILDS OFFSHORE. SHOWERS CONTINUE OVER THE AREA THIS
AFTERNOON HEAVIEST NEAR COAST RANGE AND COAST. SHOWERS WILL INCREASE
OVER THE CASCADES THIS AFTERNOON WITH SCATTERED SHOWERS SPREADING
INTO THE WESTERN VALLEYS. SNOW WILL FALL IN THE CASCADES ABOVE 3000
FEET. CONDITIONS MAINLY VFR THIS AFTERNOON THOUGH THERE ARE AREAS OF
MVFR NEAR THE COAST AND LOCALLY INLAND. THIS IS A SLIGHT RISK OF A
THUNDERSTORMS THIS AFTERNOON AND EVENING. THE SHOWERS WILL DECREASE
FROM THE NORTH TONIGHT AS THE UPPER LOW PASSES BY. VFR CONDITIONS
WILL CONTINUE TONIGHT EXCEPT FOR LOCAL MVFR NEAR HEAVIER SHOWERS.
LATE TONIGHT AND FRIDAY MORNING AREAS OF STRATUS AND PATCHY FOG WILL
DEVELOP. THIS WILL GIVE AREAS OF IFR CONDITIONS. DRIER NORTH FLOW
WILL DEVELOP FRIDAY. THIS WILL BREAK UP THE CLOUDS OVER THE AREA
WITH ALL AREAS BECOMING VFR BY MIDDAY FRIDAY.
.KPDX AND APPROACHES...VFR CONDITIONS IN THE KPDX AREA THIS
AFTERNOON AND EVENING. LOCAL MVFR CONDITIONS ARE POSSIBLE UNTIL DARK
NEAR HEAVIER SHOWERS. AREAS OF STRATUS AND PATCHY FOG WILL DEVELOP
LATE TONIGHT AND FRIDAY MORNING GIVING IFR CONDITIONS. THERE WILL BE
A 40 PERCENT CHANCE OF IFR AND KPDX EARLY FRIDAY. ALL AREAS WILL BE
VFR BY MIDDAY.
&&
.MARINE...STRONG HIGH PRESSURE OFFSHORE THIS AFTERNOON AND TONIGHT
BUILDS INTO WATERS FRIDAY. STRONG LOW PRESSURE WELL INLAND THIS
AFTERNOON WILL CONTINUE TO MOVE SOUTHEAST OVERNIGHT AND FRIDAY.
SMALL CRAFT WINDS OVER THE WATERS THIS AFTERNOON CONTINUE THIS
EVENING THEN DECREASE NEAR SHOWER AND FAR NORTH AFTER MIDNIGHT.
SMALL CRAFT WINDS WILL CONTINUE FRIDAY MORNING IN THE OFFSHORE
WATERS OF THE CENTRAL COAST. SEAS WILL BUILD TO AROUND 10 FEET THIS
EVENING THEN DECREASE NORTHERN WATERS BY MIDDAY FRIDAY.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO CASCADE
HEAD THIS AFTERNOON AND TONIGHT.
SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
THIS AFTERNOON THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO CASCADE HEAD THIS EVENING THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CASCADE HEAD TO
FLORENCE THIS EVENING THROUGH FRIDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THIS
EVENING AND TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
http://weather.gov/portland
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 092109
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
208 PM PDT THU OCT 9 2008
.SHORT TERM.....TONIGHT THROUGH SATURDAY NIGHT...A BROAD UPPER-LEVEL
TROUGH OVER THE PACIFIC NORTHWEST WILL BE REINFORCED BY A NORTHERLY JET
ALONG THE WEST SIDE OF THE TROUGH. A LIMITING FACTOR WITH THIS SYSTEM
IS A LACK OF DEEP MOISTURE...LESS THAN ONE-HALF INCH PRECIPITABLE WATER
ACCORDING TO UPPER-AIR BALLOON MEASUREMENTS AND SATELLITE ESTIMATES.
NONETHELESS...IMPULSES ALONG THE EAST SIDE OF THE JET WILL BRING
MODERATE FORCING FOR LIFT OVERNIGHT ACROSS CENTRAL OREGON AND THE
OCHOCO-JOHN DAY AREA. COMPUTER MODELS ARE IN AGREEMENT AND RUN-TO-RUN
CONSISTENCY IS ALSO GOOD FOR THIS SCENARIO. FURTHERMORE...LOWERING
SNOW LEVELS AND NORTHERLY UPSLOPE FLOW WILL FAVOR SNOW ACCUMULATIONS
ABOVE 3000 FEET ALONG NORTH FACING SLOPES. AS SUCH...THE WINTER
WEATHER ADVISORY WAS EXPANDED AND NOW INCLUDES TERRAIN ABOVE 3000 FEET
IN CENTRAL OREGON. THE WINTER WEATHER ADVISORY FOR THE JOHN DAY-OCHOCO
HIGHLANDS AND ABOVE 3000 FEET IN THE JOHN DAY BASIN ALSO REMAINS IN
EFFECT FROM 10 PM TONIGHT TO 10 AM FRIDAY MORNING. FOR ADDITIONAL
INFORMATION SEE PRODUCT PDXWSWPDT. BY FRIDAY AFTERNOON THE LOW
PRESSURE SYSTEM WILL HAVE MOVED FURTHER SOUTH INTO THE GREAT
BASIN...LEADING TO A DRYING TREND. HOWEVER SHOWERS ARE EXPECTED TO
LINGER OVER THE OCHOCO MOUNTAINS...GRANT COUNTY AND THE SOUTHERN BLUE
MOUNTAINS. FRIDAY NIGHT...SKIES WILL CLEAR ALLOWING FOR RAPID COOLING
OF AN ALREADY COOL AIR MASS. AS SUCH NEAR RECORD LOW TEMPERATURES ARE
LIKELY FRIDAY NIGHT AND PERHAPS AGAIN SATURDAY NIGHT. AFTERNOON
TEMPERATURES FRIDAY AND SATURDAY WILL BE 10 TO 15 DEGREES BELOW
NORMAL. 80
.LONG TERM...SUNDAY THROUGH THURSDAY...NORTHERLY FLOW ON THE BACK
SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS OVER THE
FORECAST AREA SUNDAY. AN UPPER LEVEL RIDGE WILL MOVE FROM THE COAST
TO IDAHO SUNDAY NIGHT AND MONDAY. SUBSIDENCE FROM THE RIDGE WILL
KEEP SKIES MOSTLY CLEAR AND WINDS LIGHT ALLOWING GOOD RADIATIONAL
COOLING AT NIGHT. TUESDAY THROUGH THURSDAY WESTERLY FLOW WITH A
COUPLE OF WEAK FAST MOVING SYSTEMS WILL BE OVER THE PACIFIC
NORTHWEST. THESE SYSTEMS MAY TRIGGER A FEW SHOWERS IN THE MOUNTAINS.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
COONFIELD
&&
.AVIATION...18Z TAFS...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH AN
APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL REMAIN
ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER TONIGHT. LOCAL
MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN AND MOUNTAIN SNOW
SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM. VISIBILITIES WILL REMAIN ABOVE
6 NM THROUGH THE DAY BUT MAY DROP TO MVFR OR IFR AT TIMES IN THE
IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS TONIGHT. WINDS ARE ALSO
EXPECTED TO INCREASE TODAY AND TONIGHT IN THE EASTERN COLUMBIA GORGE
WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 35 55 32 56 / 50 20 10 0
ALW 37 57 33 59 / 40 10 10 0
PSC 36 59 30 60 / 20 10 0 0
YKM 31 56 28 58 / 20 0 0 0
HRI 36 57 30 58 / 30 10 10 0
ELN 30 56 29 59 / 20 0 0 0
RDM 30 48 25 51 / 70 50 20 0
LGD 32 49 29 51 / 50 40 20 0
GCD 31 49 27 52 / 60 60 20 10
DLS 37 60 32 63 / 30 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ043-505-506.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80/76/76
000
FXUS65 KBOI 092047
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
245 PM MDT THU OCT 9 2008
.SHORT TERM...TONIGHT THROUGH SATURDAY...IMPRESSIVE EARLY SEASON
WINTER-LIKE STORM TAKING SHAPE OVER THE REGION. EXPECTING STRONG
NORTHWEST WINDS OF 25 TO 40 MPH WITH GUSTS TO 55 MPH ALONG A
CORRIDOR FROM ONTARIO TO BAKER...BOTH FRIDAY AND SATURDAY AFTERNOON.
WIND ADVISORIES ARE ALREADY IN EFFECT...PLEASE REFER TO BOINPWBOI
FOR THE DETAILS. RAIN AND SNOW SHOWERS WILL SPREAD ACROSS THE AREA
FROM THE NORTHWEST OVERNIGHT AND FRIDAY...WITH SNOW LEVELS FALLING
TO NEAR VALLEY FLOORS BY EARLY FRIDAY MORNING. UPPER LOW WILL DIVE
SOUTHEAST ON FRIDAY...THEN TURN BACK TO THE NORTHEAST FRIDAY NIGHT
AND SATURDAY WITH MOISTURE WRAPPING AROUND THE LOW AND INTO PORTIONS
OF SOUTHWEST IDAHO. THE LOW TRACK IS FAVORABLE FOR SIGNIFICANT SNOWS
IN THE WESTERN MAGIC VALLEY AND SOUTHERN TWIN FALLS COUNTY. WILL
ISSUE A WINTER STORM WATCH FOR THOSE AREAS FROM MIDNIGHT SATURDAY TO
MIDNIGHT SUNDAY. FOR THE TREASURE VALLEY INCLUDING BOISE...THE BEST
OPPORTUNITY FOR RAIN/SNOW COMES FRIDAY. IT APPEARS THAT THE AMOUNTS
WILL BE LIGHT...BUT A DUSTING OF SNOW ON GRASSY AREAS IS POSSIBLE.
STILL LOOKING FOR A COUPLE INCHES ABOVE 4000 FEET AND 2 TO 5 INCHES
ABOVE 6000 FEET.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE STORM WILL BE
HEADING EAST OUT OF THE AREA SUNDAY WITH IMPROVING CONDITIONS FROM
THE NORTHWEST. BY MONDAY THE STORM WILL BE OUT OF THE AREA.
TEMPERATURES WILL BE COOL SUNDAY WITH SLIGHT WARMING MONDAY. A WEAK
TROF MOVES OVER THE AREA WEDNESDAY WITH A CHANCE OF PRECIP OVER
NORTHERN AREA. THE TROF AND PREDOMINATELY WESTERLY FLOW ALOFT WILL
INHIBIT MUCH WARMUP OVER THE AREA...THUS TEMPERATURES REMAINING
ABOUT 10 DEGREES BELOW NORMAL LATTER HALF OF NEXT WEEK.
&&
.AVIATION...VFR OVER MOST OF THE AREA WILL BECOME MVFR FROM
NORTHWEST THIS EVENING AS MAJOR WINTER STORM HEADS INTO AREA.
MODERATE NORTHWEST SURFACE WINDS WILL DIMINISH SOME TONIGHT THEN
INCREASE MOST AREAS FRI AFTERNOON. CLOUDS THICKENING AND LOWER FROM
NORTHWEST THIS EVENING REMAINING VFR MOST VALLEYS BUT MVFR TO IFR
OBSCURING MOUNTAINS IN SNOW SHOWERS. LOWER CLOUDS AND SNOW MOVING
ACROSS AREAS BY FRI MORNING. WINTER CONDITIONS REMAINING OVER THE
AREA FRIDAY...SLOW IMPROVING FROM NORTHWEST BEGINNING SATURDAY.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WINTER STORM WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY
EVENING FOR IDZ016-IDZ030.
WIND ADVISORY FROM 12 PM TO 9 PM MDT FRIDAY FOR IDZ011-IDZ012.
WIND ADVISORY FROM 12 PM TO 9 PM MDT SATURDAY FOR IDZ011-IDZ012.
OR...WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
FRIDAY FOR ORZ062-ORZ063-ORZ064.
WIND ADVISORY FROM 12 PM MDT /11 AM PDT/ TO 9 PM MDT /8 PM PDT/
SATURDAY FOR ORZ062-ORZ063-ORZ064.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...BW
LONG TERM....PF/DD
AVIATION.....PF
000
FXUS66 KPDT 091825 AAB
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1125 AM PDT THU OCT 9 2008
UPDATED FOR EXPANSION OF WINTER WEATHER ADVISORY TO INCLUDE CENTRAL
OREGON
.DISCUSSION...A LOW-PRESSURE TROUGH OVER THE PACIFIC NORTHWEST IS ON
TRACK TO BRING A MUCH COOLER AIR MASS TO THE AREA TONIGHT...WITH THE
FIRST SIGNIFICANT MOUNTAIN SNOWS OF THE SEASON FOR MANY LOCATIONS.
THE WINTER WEATHER ADVISORY HAS BEEN EXPANDED TO INCLUDE CENTRAL
OREGON IN ADDITION TO THE OCHOCO JOHN DAY HIGHLANDS AND JOHN DAY
BASIN FROM 10 PM THIS EVENING TO 10 AM PDT FRIDAY...SEE PRODUCT
PDXWSWPDT FOR DETAILS. SNOW LEVELS WILL LOWER TO AROUND 3000 FEET
TONIGHT. 80
&&
.AVIATION...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH AN
APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL
REMAIN ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER
TONIGHT. LOCAL MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN
AND MOUNTAIN SNOW SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM.
VISIBILITIES WILL REMAIN ABOVE 6 NM THROUGH THE DAY BUT MAY DROP TO
MVFR OR IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT. WINDS ARE ALSO EXPECTED TO INCREASE TODAY AND TONIGHT IN
THE EASTERN COLUMBIA GORGE WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
&&
.PREV DISCUSSION... /ISSUED 255 AM PDT THU OCT 9 2008/
SHORT TERM...TODAY THROUGH SATURDAY. FREEZE WARNINGS WERE ISSUED
FOR THE OREGON PORTION OF THE LOWER COLUMBIA BASIN AND BLUE MTN
FOOTHILLS. CURRENT TEMPS RANGE FROM 32-37 DEGREES OVER MOST OF THIS
AREA AND TEMPS WILL DECREASE ANOTHER DEGREE OR TWO THIS MORNING. MID
LEVEL CLOUDS ARE STARTING TO INCREASE AHEAD OF AN APPROACHING UPPER
LEVEL TROUGH. WATER VAPOR LOOPS SHOW ENERGY DIVING DOWN THE BACKSIDE
OF THE TROUGH FORCING IT TO ELONGATE OFF THE COAST. A CLOSED LOW
WILL DEVELOP ALONG THE BOTTOM OF THE TROUGH AND OVER THE GREAT BASIN
BY FRIDAY. A NORTHERLY FLOW ALOFT WILL SPREAD COLD AIR THROUGHOUT
EASTERN WA/OR...LOWERING SNOW LEVELS TO NEAR 3500 FEET. SNOW
ACCUMULATIONS WILL BE LIGHT OVER THE EASTERN WASHINGTON ZONES...BUT
FEEL THAT 1-3 INCHES ARE POSSIBLE OVER CENTRAL AND EASTERN OREGON
ABOVE 4000 FEET. THE WRAP-AROUND MOISTURE WILL BE FOCUSED OVER THE
SOUTHERN BLUES AND THE OCHOCO-JOHN DAY HIGHLANDS TONIGHT AND FRIDAY
MORNING. THIS IS THE AREA THAT WILL SEE THE HEAVIEST
ACCUMULATIONS. THIS MEETS EARLY SEASON SNOW ADVISORY CRITERIA FOR
THE OCHOCO-JOHN DAY HIGHLANDS AND WILL ISSUE A WINTER ADVISORY FOR
SNOW TONIGHT THROUGH FRIDAY MORNING.
THE NORTHERLY FLOW ALOFT WILL SPREAD DRIER AIR FROM THE NORTH
TONIGHT AND FRIDAY. BY FRIDAY NIGHT AND SATURDAY...PRECIPITATION
WILL MAINLY BE CONFINED TO THE MOUNTAINS OF UNION, WALLOWA, AND
GRANT COUNTIES WHERE ISOLATED TO SCATTERED SNOW SHOWERS ARE
EXPECTED. IT WILL BE VERY COLD FRIDAY NIGHT...AND FREEZING TEMPS
ARE EXPECTED OVER MOST OF THE FORECAST AREA. AFTERNOON TEMPS ON
FRIDAY AND SATURDAY WILL BE 10-15 DEGREES BELOW NORMAL. A FAIRLY
TIGHT NORTHERLY GRADIENT WILL BRING LOCALLY BREEZY WINDS ON
FRIDAY...MAINLY IN AREAS SOUTH AND EAST OF THE BLUE MOUNTAINS AND
JOHN DAY BASIN. JOHNSON
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE UPPER LOW WILL
CONTINUE TO MOVE TO THE EAST WITH A DEEP NORTHERLY FLOW IN ITS WAKE
ON SUNDAY. AT THE SAME TIME AN UPPER RIDGE WILL BE BUILDING OFF THE
COAST. IT WILL BEGIN TO MOVE INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THIS WILL RESULT IN A GRADUAL WARMING TREND WITH A
CONTINUATION OF A DRY PERIOD. NIGHT TIME TEMPERATURE READINGS
HOWEVER WILL CONTINUE TO BE VERY COOL WITH MANY AREAS NEAR FREEZING.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO THROUGH MONDAY AND
THEN BEGIN TO DIVERGE FROM EACH OTHER ON TUESDAY. NEVERTHELESS THE
RIDGE WILL BEGIN TO BREAK DOWN BY TUESDAY MORNING WITH A FASTER
PROGRESSIVE FLOW PATTERN. THE MODELS THEN SHOW GREATER DIFFERENCES
WEDNESDAY AND THURSDAY. DEPENDING ON WHICH MODEL IS CORRECT...THERE
MAY BE EITHER DRY AND WARMER CONDITIONS UNDER AN UPPER RIDGE OR
MARGINALLY DRY BUT COOLER CONDITIONS UNDER A NW FLOW. UNTIL A BETTER
CONSENSUS IS REACHED SIGNIFICANT CHANGES WILL NOT BE MADE AFTER
MONDAY. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 56 37 55 32 / 20 50 20 10
ALW 57 39 57 33 / 20 40 10 10
PSC 59 35 59 30 / 20 20 10 0
YKM 58 30 56 28 / 20 20 0 0
HRI 59 35 57 30 / 20 20 10 10
ELN 57 29 56 29 / 20 20 0 0
RDM 50 32 48 25 / 20 70 50 20
LGD 50 33 49 29 / 20 40 40 20
GCD 51 34 49 27 / 20 60 60 20
DLS 58 38 60 32 / 20 30 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM
PDT FRIDAY FOR ORZ043-505-506.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80
000
FXUS66 KPDT 091737 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1035 AM PDT THU OCT 9 2008
UPDATED AVIATION DISCUSSION
.DISCUSSION...REST OF TODAY THROUGH TONIGHT...CURRENT DOPPLER RADAR
SHOWS WEAK RETURNS MAINLY ACROSS THE COLUMBIA BASIN. FOR THE MOST
PART ANY HYDROMETEORS FALLING FROM THIS CONVECTION WILL EVAPORATE
BEFORE REACHING THE GROUND. HOWEVER...OCCASIONAL SPRINKLES ARE
POSSIBLE. THIS AFTERNOON THE AIR MASS WILL BECOME WEAKLY UNSTABLE
AND ISOLATED SHOWERS ARE EXPECTED TO DEVELOP. HOWEVER...CONVECTION
IS NOT EXPECTED TO BE DEEP ENOUGH FOR THUNDERSTORMS. A LOW-PRESSURE
TROUGH OVER THE PACIFIC NORTHWEST WILL BRING A MUCH COOLER AIR MASS
TO THE AREA TONIGHT...WITH THE FIRST SIGNIFICANT MOUNTAIN SNOWS OF
THE SEASON FOR MANY LOCATIONS. A WINTER WEATHER ADVISORY IS IN
EFFECT FOR THE OCHOCO JOHN DAY HIGHLANDS AND JOHN DAY BASIN FROM 10
PM THIS EVENING TO 10 AM PDT FRIDAY...SEE PRODUCT PDXWSWPDT FOR
DETAILS. FORECAST FOR NORTHERLY WIND SPEEDS IN THE GRANDE RONDE
VALLEY FOR THIS AFTERNOON WERE INCREASED SLIGHTLY...TO 10 TO 20 MPH
WITH HIGHER GUSTS. 80
&&
.AVIATION...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH AN
APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL
REMAIN ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER
TONIGHT. LOCAL MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN
AND MOUNTAIN SNOW SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM.
VISIBILITIES WILL REMAIN ABOVE 6 NM THROUGH THE DAY BUT MAY DROP TO
MVFR OR IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT. WINDS ARE ALSO EXPECTED TO INCREASE TODAY AND TONIGHT IN
THE EASTERN COLUMBIA GORGE WITH WIND SPEEDS REACHING 15 TO 25 KTS. 76
%%
.PREV DISCUSSION... /ISSUED 255 AM PDT THU OCT 9 2008/
SHORT TERM...TODAY THROUGH SATURDAY. FREEZE WARNINGS WERE ISSUED
FOR THE OREGON PORTION OF THE LOWER COLUMBIA BASIN AND BLUE MTN
FOOTHILLS. CURRENT TEMPS RANGE FROM 32-37 DEGREES OVER MOST OF THIS
AREA AND TEMPS WILL DECREASE ANOTHER DEGREE OR TWO THIS MORNING. MID
LEVEL CLOUDS ARE STARTING TO INCREASE AHEAD OF AN APPROACHING UPPER
LEVEL TROUGH. WATER VAPOR LOOPS SHOW ENERGY DIVING DOWN THE BACKSIDE
OF THE TROUGH FORCING IT TO ELONGATE OFF THE COAST. A CLOSED LOW
WILL DEVELOP ALONG THE BOTTOM OF THE TROUGH AND OVER THE GREAT BASIN
BY FRIDAY. A NORTHERLY FLOW ALOFT WILL SPREAD COLD AIR THROUGHOUT
EASTERN WA/OR...LOWERING SNOW LEVELS TO NEAR 3500 FEET. SNOW
ACCUMULATIONS WILL BE LIGHT OVER THE EASTERN WASHINGTON ZONES...BUT
FEEL THAT 1-3 INCHES ARE POSSIBLE OVER CENTRAL AND EASTERN OREGON
ABOVE 4000 FEET. THE WRAP-AROUND MOISTURE WILL BE FOCUSED OVER THE
SOUTHERN BLUES AND THE OCHOCO-JOHN DAY HIGHLANDS TONIGHT AND FRIDAY
MORNING. THIS IS THE AREA THAT WILL SEE THE HEAVIEST
ACCUMULATIONS. THIS MEETS EARLY SEASON SNOW ADVISORY CRITERIA FOR
THE OCHOCO-JOHN DAY HIGHLANDS AND WILL ISSUE A WINTER ADVISORY FOR
SNOW TONIGHT THROUGH FRIDAY MORNING.
THE NORTHERLY FLOW ALOFT WILL SPREAD DRIER AIR FROM THE NORTH
TONIGHT AND FRIDAY. BY FRIDAY NIGHT AND SATURDAY...PRECIPITATION
WILL MAINLY BE CONFINED TO THE MOUNTAINS OF UNION, WALLOWA, AND
GRANT COUNTIES WHERE ISOLATED TO SCATTERED SNOW SHOWERS ARE
EXPECTED. IT WILL BE VERY COLD FRIDAY NIGHT...AND FREEZING TEMPS
ARE EXPECTED OVER MOST OF THE FORECAST AREA. AFTERNOON TEMPS ON
FRIDAY AND SATURDAY WILL BE 10-15 DEGREES BELOW NORMAL. A FAIRLY
TIGHT NORTHERLY GRADIENT WILL BRING LOCALLY BREEZY WINDS ON
FRIDAY...MAINLY IN AREAS SOUTH AND EAST OF THE BLUE MOUNTAINS AND
JOHN DAY BASIN. JOHNSON
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE UPPER LOW WILL
CONTINUE TO MOVE TO THE EAST WITH A DEEP NORTHERLY FLOW IN ITS WAKE
ON SUNDAY. AT THE SAME TIME AN UPPER RIDGE WILL BE BUILDING OFF THE
COAST. IT WILL BEGIN TO MOVE INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THIS WILL RESULT IN A GRADUAL WARMING TREND WITH A
CONTINUATION OF A DRY PERIOD. NIGHT TIME TEMPERATURE READINGS
HOWEVER WILL CONTINUE TO BE VERY COOL WITH MANY AREAS NEAR FREEZING.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO THROUGH MONDAY AND
THEN BEGIN TO DIVERGE FROM EACH OTHER ON TUESDAY. NEVERTHELESS THE
RIDGE WILL BEGIN TO BREAK DOWN BY TUESDAY MORNING WITH A FASTER
PROGRESSIVE FLOW PATTERN. THE MODELS THEN SHOW GREATER DIFFERENCES
WEDNESDAY AND THURSDAY. DEPENDING ON WHICH MODEL IS CORRECT...THERE
MAY BE EITHER DRY AND WARMER CONDITIONS UNDER AN UPPER RIDGE OR
MARGINALLY DRY BUT COOLER CONDITIONS UNDER A NW FLOW. UNTIL A BETTER
CONSENSUS IS REACHED SIGNIFICANT CHANGES WILL NOT BE MADE AFTER
MONDAY. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 56 37 55 32 / 20 30 20 10
ALW 57 39 57 33 / 20 30 10 10
PSC 59 35 59 30 / 20 20 10 0
YKM 58 30 56 28 / 20 20 0 0
HRI 59 35 57 30 / 20 20 10 10
ELN 57 29 56 29 / 20 20 0 0
RDM 50 32 48 25 / 20 40 40 20
LGD 50 33 49 29 / 20 40 40 20
GCD 51 34 49 27 / 20 60 60 20
DLS 58 38 60 32 / 20 30 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ505-506.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80
000
FXUS65 KBOI 091559
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
958 AM MDT THU OCT 9 2008
.DISCUSSION...UPPER TROUGH IS STARTING TO DEEPEN OVER THE REGION
WITH CLOUDS AND SHOWERS SHOWING UP IN SATELLITE/RADAR IMAGERY TO THE
WEST OF BURNS AND BAKER. CLOUDS WILL CONTINUE TO INCREASE THROUGH
THE DAY...BUT MOST AREAS WILL BE SPARED BY PRECIP. ISOLATED SHOWERS
WILL DEVELOP IN THE AFTERNOON IN THE NORTHERN AND WESTERN FRINGES OF
HARNEY AND BAKER COUNTY...AS WELL AS THE WEST CENTRAL MOUNTAINS NEAR
MCCALL. CLOUD SHIELD AND BAND OF LIGHT PRECIP LOCATED FROM TWIN
FALLS TO JACKSON DEVELOPED NORTH OF A FRONTAL BOUNDARY WHICH LOCATED
IN NORTHERN UTAH. THE CLOUDS AND PRECIP WILL SHIFT EAST OF TWIN
FALLS THIS MORNING...LEAVING BEHIND MOSTLY CLEAR SKIES. THE CLEAR
SKIES...ALONG WITH AN ALREADY TIGHT NW-SE SURFACE PRESSURE
GRADIENT...WILL ALLOW FOR GUSTY NORTHWEST WINDS TO DEVELOP IN THE
AFTERNOON. THESE WINDS WILL BE CLOSE TO ADVISORY LEVEL SPEEDS. WINDS
WILL ALSO BECOME GUSTY DOWN THE VALLEY FROM BAKER TO MOUNTAIN HOME.
ALL THIS IS HANDLED WELL IN CURRENT FORECAST.
&&
.AVIATION...VFR THIS THROUGH THE DAY OVER THE AREA BUT CLOUDS
INCREASING FROM THE NORTHWEST THIS AFTERNOON WILL LOWER WITH
MOUNTAIN OBSCURATION IN SNOW SHOWERS BY EVENING IN THE MOUNTAINS
NEAR MCCALL AND BAKER CITY. CLOUDS AND SHOWERS WILL CONTINUE
INCREASING FROM NW OVERNIGHT TONIGHT WITH WIDESPREAD MVFR AND
MOUNTAIN OBSCURATION IN RAIN AND SNOW ALL AREAS FRIDAY. NORTHWEST
SURFACE WIND WILL INCREASE DURING THE DAY TODAY AND REMAIN BREEZY
TONIGHT. LOOK FOR STRONG WIND GUSTS FROM THE NORTHWEST ON SATURDAY.
&&
.PREV DISCUSSION...
SHORT TERM...THE UPPER LEVEL TROUGH THAT WILL BRING COOLER
TEMPERATURES AND THE FIRST CHANCE OF SNOW WAS MOVING INTO WASHINGTON
AND OREGON EARLY THIS MORNING. MODELS A BIT SLOWER ON THE TIMING OF
THE PRECIPITATION MOVING INTO THE AREA AND CURRENT SATELLITE
PICTURES AND RADARS CONFIRM THIS. HAVE BACKED OFF ON POPS FOR THIS
MORNING AND THIS AFTERNOON AND ONLY MADE MINOR CHANGES TO TONIGHT
AND FRIDAY. TEMPERATURES LOOK GOOD BUT DID LOWER A FEW MAX
TEMPERATURES TODAY AS THE COLD AIR BEGINS TO MOVE INTO THE AREA.
MODELS STILL SHOW THE SURFACE PRESSURE GRADIENT TIGHTENING AS THIS
SYSTEM DIGS TO THE SOUTH ALLOWING FOR NEAR ADVISORY LEVEL WINDS THIS
AFTERNOON AND FRIDAY AFTERNOON. AS THE COLDER AIR CONTINUES TO MOVE
INTO THE AREA TONIGHT AND FRIDAY SNOW LEVELS WILL FALL TO VALLEY
FLOORS BY FRIDAY. SNOW AMOUNTS OF UP TO 2 INCHES ARE POSSIBLE
BETWEEN 4000 AND 6000 FEET...AND 2 TO 4 INCHES ABOVE 6000 FEET.
SNOW AMOUNTS JUST BELOW WINTER WEATHER ADVISORY AMOUNTS SO WILL
MENTION IN SPECIAL WEATHER STATEMENT. WILL CONTINUE TO MONITOR THIS
WINTER-LIKE STORM FOR POSSIBLE WINTER WEATHER ADVISORY.
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY...STRONG COLD UPPER LOW
WILL REACH ITS SOUTHERNMOST POINT NEAR LAS ABOUT 12Z SATURDAY THEN
TURN BACK NNEWD THROUGH UTAH...THEN WRN WYOMING...THEN OUT OF OUR
AREA LATE SUNDAY. AFTER THAT A HIGH AMPLITUDE UPPER RIDGE WILL COME
IN FROM THE N PACIFIC WITH DRIER AND WARMER AIR. BUT WHILE THE
UPPER LOW IS IN THE GREAT BASIN THIS WEEKEND OUR ZONES...ESPECIALLY
SOUTHERN IDAHO ZONES...WILL BE COLD AND WINDY ALONG WITH A CHANCE OF
SNOW SHOWERS...MIXED WITH RAIN IN THE LOWER VALLEYS. THE WESTERN
MAGIC VALLEY AND SOUTHERN TWIN FALLS COUNTY ARE STILL THE MOST
FAVORED AREAS FOR POSSIBLE ACCUMULATING SNOW FRIDAY EVENING THROUGH
SUNDAY MORNING. THAT IS WHERE MOISTURE WILL WRAP AROUND THE UPPER
LOW AS IT PASSES BY IN UTAH. ALSO...A TIGHT NW-SE SURFACE PRESSURE
GRADIENT WILL CONTINUE GUSTY NW WINDS IN SOUTHERN IDAHO FRIDAY NIGHT
AND SATURDAY...GRADUALLY DECREASING SATURDAY NIGHT AND SUNDAY.
TEMPERATURES THROUGH MONDAY MORNING WILL BE FAR BELOW NORMAL...MAX
TEMPS IN THE UPPER 30S TO LOWER 50S...MIN TEMPS IN THE TEENS TO
LOWER 30S. SEE NEW SPSBOI FOR MORE INFO. TEMPS WILL RECOVER TO
NORMAL BY TUESDAY. ON WEDNESDAY A SHORT WAVE TROUGH WILL REPLACE THE
UPPER RIDGE OF MONDAY AND TUESDAY AND WILL BRING A SLIGHT CHANCE OF
RAIN AND SNOW SHOWERS TO OUR NRN ZONES...AND SEVERAL DEGREES COOLING
TO ALL ZONES.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...BW
AVIATION.....PF
PREV SHORT TERM...JA
PREV LONG TERM....LC
000
FXUS66 KMFR 091555
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
855 AM PDT THU OCT 9 2008
.DISCUSSION...PRECIPITATION ASSOCIATED WITH A INCOMING SHORTWAVE
IS INCREASING ALONG THE COAST. RIGHT NOW MOST OF THE PRECIPITATION
IS JUST NORTH OF THE CWA...BUT THAT WILL CHANGE AS THE MORNING
PROGRESSES AND AS WE MOVE INTO THE AFTERNOON. MADE SOME
ADJUSTMENTS FOR THE ZONES MOSTLY TO REFLECT HIGHER POPS FOR THIS
AFTERNOON OVER THE HIGHER TERRAIN AND IN THE ROGUE VALLEY.
THE 12Z NAM AND GFS CONTINUE TO BE IN GOOD AGREEMENT WITH RESPECT
TO THE EVOLUTION OF THE UPPER LEVEL TROUGH THAT WILL MOVE IN TO
THE AREA THIS AFTERNOON AND TONIGHT. CURRENT VIS AND IR IMAGERY
SHOWS THE COLDER AIR OVER THE WATER AS EVIDENCED BY THE POPCORN
TYPE CLOUD FORMATION. THIS WILL MOVE INTO THE AREA TONIGHT THROUGH
FRIDAY WHICH WILL KEEP THE SHOWERS GOING.
&&
.AVIATION...THE LEADING EDGE OF AN UPPER LEVEL DISTURBANCE IS AT
THE COAST AND WILL MOVE INLAND DURING THE MORNING AND AFTERNOON.
THIS WILL RESULT IN INCREASING CLOUD COVER ALONG AND WEST OF THE
CASCADES. CIGS WILL LOWER SOME THIS AFTERNOON WITH MTNS
OCCASIONALLY BEING OBSCURED...BUT VFR CONDITIONS SHOULD BE THE
PREDOMINATE CONDITION WITH LOCAL MVFR CONDITIONS NEAR KRBG AND
KMFR THIS AFTERNOON. SHOWERS WILL DEVELOP LATE THIS MORNING AND
LAST INTO TONIGHT.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
ORZ024-ORZ025-ORZ026.
FREEZE WATCH FROM LATE SATURDAY NIGHT THROUGH SUNDAY MORNING FOR
ORZ024-ORZ025-ORZ026.
CA...FREEZE WATCH FROM LATE FRIDAY NIGHT THROUGH SATURDAY MORNING FOR
CAZ080-CAZ081-CAZ082.
FREEZE WATCH FROM LATE SATURDAY NIGHT THROUGH SUNDAY MORNING FOR
CAZ080-CAZ081-CAZ082.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM
PDT SATURDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 AM PDT SATURDAY
FOR PZZ350-PZZ356-PZZ370-PZZ376.
$$
PETRUCELLI
000
FXUS66 KPQR 091549
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
900 AM PDT THU OCT 09 2008
.SYNOPSIS...A TROUGH OF LOW PRESSURE FROM THE GULF OF ALASKA IS
DROPPING SOUTHEAST INTO THE PACIFIC NORTHWEST TODAY...USHERING IN A
MUCH COOLER AIR MASS WITH SNOW LEVELS FALLING TO AROUND 3000 FEET AND
SOME SNOW ACCUMULATIONS IN THE MOUNTAINS. SHOWERS ARE SPREADING
ACROSS THE COAST RANGE THIS MORNING AND WILL REACH THE MOUNTAINS
DURING THE DAY. THE UPPER LEVEL TROUGH WILL SHIFT EAST THIS WEEKEND
WITH NORTHERLY FLOW ALOFT AS A RIDGE OF HIGH PRESSURE ALOFT BUILDS .
OFFSHORE. THE RIDGE IS WILL MOVE INLAND BY SUNDAY...BUT IS EXPECTED
TO BREAK DOWN EARLY NEXT WEEK...ALLOWING A PACIFIC COLD FRONT TO MOVE
IN.
&&
.SHORT TERM...A LARGE COOL UPPER LEVEL TROUGH IS SETTLING SOUTH OVER
THE PACIFIC NORTHWEST TODAY AND A SHORTWAVE WITHIN THE TROUGH IS
EVIDENT ON NATIONAL WEATHER SERVICE RADAR AND SATELLITE SPREADING
INTO THE COAST RANGE THIS MORNING WITH COOLING INFRARED TOPS IN A
WELL ORGANIZED AREA OF SHOWERS. THIS FEATURE WILL CONTINUE TO MOVE
INLAND ACROSS THE FORECAST AREA TODAY WITH MODELS SHOWING INCREASING
INSTABILITY WITH LIFTED INDEX JUST AROUND ZERO FOR POSSIBILITY OF
THUNDERSTORMS OVER THE NORTHERN MARINE AND COASTAL ZONES THIS
MORNING...THEN SPREADING INLAND OVER THE NORTHERN ZONES FOR THE
AFTERNOON AND EARLY EVENING. SHOWERS SHOULD BE QUITE ACTIVE IN THE
AFTERNOON AS THE NEXT SHORTWAVE DROPS IN. THE MORNING FREEZING LEVEL
AT SALEM WAS 4300 FEET AND MODEL 1000/700 MILLIBAR THICKNESS SUPPORTS
SNOW LEVELS BELOW PASS LEVELS TODAY AND TONIGHT FALLING DOWN TO NEAR
2500 FEET BY TONIGHT AS THE COLD AIR CONTINUES TO SPREAD INTO THE
FORECAST AREA. THERE APPEARS TO BE SUFFICIENT PRECIPITATION WITH THE
SYSTEM...BRIEFLY ENHANCED BY AN OROGRAPHICALLY FAVORED NW FLOW...TO
YIELD A FEW INCHES OF SNOW IN THE CASCADES...BUT AMOUNTS SHOULD
REMAIN BELOW ADVISORY CRITERIA SO A SPECIAL WEATHER STATEMENT
ADDRESSES THAT. SINCE THIS WEATHER SYSTEM ORIGINATED AT MUCH HIGHER
LATITUDES...IT WILL BE THE COLDEST SYSTEM TO MOVE INTO THE PACIFIC
NORTHWEST SO FAR THIS FALL SEASON. MODELS ARE IN REASONABLY GOOD
AGREEMENT IN SHOWING THE DEVELOPING
WEST COAST TROUGH TO BE SLOW TO PULL OFF TO THE EAST FRI AND SAT AS
HIGH PRESSURE DEVELOPS OFFSHORE. SOME LINGERING SHOWERS ARE EXPECTED
IN THE CASCADES THROUGH FRI EVENING. AFTERNOON TEMPERATURES WILL
SLOWLY REBOUND FRI AND SAT...BUT IT COULD BE A FROSTY NIGHT FRIDAY
NIGHT A POSSIBLY SATURDAY NIGHT AS THE COOL DRY AIR MASS RADIATES
WELL UNDER CLEARING SKIES. WILLSON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
THE FORECAST AREA REMAINS DRY UNTIL MONDAY AFTERNOON OR EARLY
EVENING. AFTERWARD MODELS BREAK DOWN THE UPPER RIDGE AND ALLOW A
PACIFIC FRONTAL SYSTEM TO SPREAD SOME LIGHT RAIN ACROSS THE REGION.
TRENDED POPS ON MONDAY AND TUESDAY TOWARDS CLIMO. THOUGH CONFIDENCE
DECREASES CONSIDERABLY FROM MONDAY ONWARD...IT APPEARS THAT WE
TRANSITION TO ANOTHER PERIOD OF PROGRESSIVE FLOW AND THUS WET
WEATHER BY TUESDAY. DALTON
&&
.AVIATION...COLD PACIFIC TROUGH APPROACHING THE COAST WILL MOVE
ACROSS THE AREA TODAY AND MOVE EAST OF THE CASCADES BY LATE IN THE
DAY. COLD UPPER LOW WILL MOVE INTO NORTHWEST OREGON THIS EVENING
THEN MOVE TO NORTHERN CALIFORNIA BY FRIDAY MORNING. SHOWERS ALONG
THE COAST WILL SPREAD OVER ALL THE AREA BY EARLY AFTERNOON AND
CONTINUE THROUGH EARLY EVENING. THERE WILL BE AREAS OF MVFR
CONDITIONS ALONG THE COAST ALONG WITH LOCAL IFR VISIBILITIES IN
HEAVIER SHOWERS. THE AIR MASS IN SOMEWHAT UNSTABLE TODAY AND INTO
EARLY EVENING AND THERE WILL BE A RISK OF ISOLATED THUNDERSTORMS
WITH SMALL HAIL THROUGH EARLY EVENING. THERE WILL BE OCCASIONAL MVFR
CONDITIONS INLAND THIS AFTERNOON AND EVENING. SNOW SHOWERS WILL FALL
OVER THE CASCADES ABOVE 2500 FEET TODAY AND TONIGHT. SHOWERS WILL
BECOMING MORE SCATTERED MAINLY NEAR THE COAST AND CASCADES AFTER
DARK. MOST AREAS TONIGHT WILL BE VFR WITH LOCAL MVFR NEAR SHOWERS.
LOCAL IFR IS POSSIBLE LATE TONIGHT WITH PATCHY FOG OVER INLAND
VALLEYS.
.KPDX AND APPROACHES...VFR CONDITIONS IN THE KPDX AREA THIS MORNING
LOCAL MVFR IS POSSIBLE THIS AFTERNOON AND EARLY EVENING NEAR HEAVIER
SHOWERS. THERE IS A 20 PERCENT RISK OF A THUNDERSTORM IN THE KPDX
AREA THIS AFTERNOON INTO EARLY EVENING. PATCHY FOG LATE TONIGHT WILL
GIVE LOCAL IFR CONDITIONS.
&&
.MARINE...TROUGH ALONG COAST MOVES ASHORE THIS MORNING. STRONG HIGH
PRESSURE OFFSHORE TODAY AND TONIGHT. SMALL CRAFT WINDS IN THE OUTER
WATERS THIS MORNING WILL SPREAD OVER ALL THE WATERS THIS AFTERNOON
AND CONTINUE TONIGHT. WINDS WILL DECREASE NEAR SHORE AND FAR NORTH
AFTER MIDNIGHT. SEAS BELOW 10 FEET THIS MORNING WILL BUILD TO 10
FEET OR A LITTLE HIGHER THIS AFTERNOON AND CONTINUE TONIGHT.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO CASCADE
HEAD TODAY AND TONIGHT.
SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
TODAY THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO CASCADE HEAD THIS AFTERNOON THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CASCADE HEAD TO
FLORENCE THIS EVENING THROUGH FRIDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THIS
EVENING AND TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
Http://weather.gov/portland
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 091511
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
810 AM PDT THU OCT 9 2008
.DISCUSSION...REST OF TODAY THROUGH TONIGHT...CURRENT DOPPLER RADAR
SHOWS WEAK RETURNS MAINLY ACROSS THE COLUMBIA BASIN. FOR THE MOST
PART ANY HYDROMETEORS FALLING FROM THIS CONVECTION WILL EVAPORATE
BEFORE REACHING THE GROUND. HOWEVER...OCCASIONAL SPRINKLES ARE
POSSIBLE. THIS AFTERNOON THE AIR MASS WILL BECOME WEAKLY UNSTABLE
AND ISOLATED SHOWERS ARE EXPECTED TO DEVELOP. HOWEVER...CONVECTION
IS NOT EXPECTED TO BE DEEP ENOUGH FOR THUNDERSTORMS. A LOW-PRESSURE
TROUGH OVER THE PACIFIC NORTHWEST WILL BRING A MUCH COOLER AIR MASS
TO THE AREA TONIGHT...WITH THE FIRST SIGNIFICANT MOUNTAIN SNOWS OF
THE SEASON FOR MANY LOCATIONS. A WINTER WEATHER ADVISORY IS IN
EFFECT FOR THE OCHOCO JOHN DAY HIGHLANDS AND JOHN DAY BASIN FROM 10
PM THIS EVENING TO 10 AM PDT FRIDAY...SEE PRODUCT PDXWSWPDT FOR
DETAILS. FORECAST FOR NORTHERLY WIND SPEEDS IN THE GRANDE RONDE
VALLEY FOR THIS AFTERNOON WERE INCREASED SLIGHTLY...TO 10 TO 20 MPH
WITH HIGHER GUSTS. 80
&&
.PREV DISCUSSION... /ISSUED 255 AM PDT THU OCT 9 2008/
SHORT TERM...TODAY THROUGH SATURDAY. FREEZE WARNINGS WERE ISSUED
FOR THE OREGON PORTION OF THE LOWER COLUMBIA BASIN AND BLUE MTN
FOOTHILLS. CURRENT TEMPS RANGE FROM 32-37 DEGREES OVER MOST OF THIS
AREA AND TEMPS WILL DECREASE ANOTHER DEGREE OR TWO THIS MORNING. MID
LEVEL CLOUDS ARE STARTING TO INCREASE AHEAD OF AN APPROACHING UPPER
LEVEL TROUGH. WATER VAPOR LOOPS SHOW ENERGY DIVING DOWN THE BACKSIDE
OF THE TROUGH FORCING IT TO ELONGATE OFF THE COAST. A CLOSED LOW
WILL DEVELOP ALONG THE BOTTOM OF THE TROUGH AND OVER THE GREAT BASIN
BY FRIDAY. A NORTHERLY FLOW ALOFT WILL SPREAD COLD AIR THROUGHOUT
EASTERN WA/OR...LOWERING SNOW LEVELS TO NEAR 3500 FEET. SNOW
ACCUMULATIONS WILL BE LIGHT OVER THE EASTERN WASHINGTON ZONES...BUT
FEEL THAT 1-3 INCHES ARE POSSIBLE OVER CENTRAL AND EASTERN OREGON
ABOVE 4000 FEET. THE WRAP-AROUND MOISTURE WILL BE FOCUSED OVER THE
SOUTHERN BLUES AND THE OCHOCO-JOHN DAY HIGHLANDS TONIGHT AND FRIDAY
MORNING. THIS IS THE AREA THAT WILL SEE THE HEAVIEST
ACCUMULATIONS. THIS MEETS EARLY SEASON SNOW ADVISORY CRITERIA FOR
THE OCHOCO-JOHN DAY HIGHLANDS AND WILL ISSUE A WINTER ADVISORY FOR
SNOW TONIGHT THROUGH FRIDAY MORNING.
THE NORTHERLY FLOW ALOFT WILL SPREAD DRIER AIR FROM THE NORTH
TONIGHT AND FRIDAY. BY FRIDAY NIGHT AND SATURDAY...PRECIPITATION
WILL MAINLY BE CONFINED TO THE MOUNTAINS OF UNION, WALLOWA, AND
GRANT COUNTIES WHERE ISOLATED TO SCATTERED SNOW SHOWERS ARE
EXPECTED. IT WILL BE VERY COLD FRIDAY NIGHT...AND FREEZING TEMPS
ARE EXPECTED OVER MOST OF THE FORECAST AREA. AFTERNOON TEMPS ON
FRIDAY AND SATURDAY WILL BE 10-15 DEGREES BELOW NORMAL. A FAIRLY
TIGHT NORTHERLY GRADIENT WILL BRING LOCALLY BREEZY WINDS ON
FRIDAY...MAINLY IN AREAS SOUTH AND EAST OF THE BLUE MOUNTAINS AND
JOHN DAY BASIN. JOHNSON
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE UPPER LOW WILL
CONTINUE TO MOVE TO THE EAST WITH A DEEP NORTHERLY FLOW IN ITS WAKE
ON SUNDAY. AT THE SAME TIME AN UPPER RIDGE WILL BE BUILDING OFF THE
COAST. IT WILL BEGIN TO MOVE INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THIS WILL RESULT IN A GRADUAL WARMING TREND WITH A
CONTINUATION OF A DRY PERIOD. NIGHT TIME TEMPERATURE READINGS
HOWEVER WILL CONTINUE TO BE VERY COOL WITH MANY AREAS NEAR FREEZING.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO THROUGH MONDAY AND
THEN BEGIN TO DIVERGE FROM EACH OTHER ON TUESDAY. NEVERTHELESS THE
RIDGE WILL BEGIN TO BREAK DOWN BY TUESDAY MORNING WITH A FASTER
PROGRESSIVE FLOW PATTERN. THE MODELS THEN SHOW GREATER DIFFERENCES
WEDNESDAY AND THURSDAY. DEPENDING ON WHICH MODEL IS CORRECT...THERE
MAY BE EITHER DRY AND WARMER CONDITIONS UNDER AN UPPER RIDGE OR
MARGINALLY DRY BUT COOLER CONDITIONS UNDER A NW FLOW. UNTIL A BETTER
CONSENSUS IS REACHED SIGNIFICANT CHANGES WILL NOT BE MADE AFTER
MONDAY. 88
AVIATION...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH AN
APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL
REMAIN ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER
TONIGHT. LOCAL MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN
AND MOUNTAIN SNOW SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM.
VISIBILITIES WILL REMAIN ABOVE 6 NM THROUGH THE DAY BUT MAY DROP TO
MVFR OR IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT. WINDS ARE ALSO EXPECTED TO INCREASE TODAY AND TONIGHT WITH
WIND SPEEDS REACHING 15 TO 25 KTS IN THE EASTERN COLUMBIA GORGE AND
10 TO 20 KTS ELSEWHERE THIS AFTERNOON AND EVENING. THE WINDS WILL
THEN DECREASE LATER TONIGHT BACK TO 5 TO 15 KTS IN MOST AREAS. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 56 37 55 32 / 20 30 20 10
ALW 57 39 57 33 / 20 30 10 10
PSC 59 35 59 30 / 20 20 10 0
YKM 58 30 56 28 / 20 20 0 0
HRI 59 35 57 30 / 20 20 10 10
ELN 57 29 56 29 / 20 20 0 0
RDM 50 32 48 25 / 20 40 40 20
LGD 50 33 49 29 / 20 40 40 20
GCD 51 34 49 27 / 20 60 60 20
DLS 58 38 60 32 / 20 30 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ505-506.
FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR ORZ044-501.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
80
000
FXUS66 KPQR 091003
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
301 AM PDT THU OCT 09 2008
.SYNOPSIS...A TROUGH OF LOW PRESSURE FROM THE GULF OF ALASKA WILL
DROP SOUTHEAST INTO THE PACIFIC NORTHWEST TODAY...USHERING IN A MUCH
COOLER AIR MASS. SHOWERS WITH SNOW SHOWERS IN THE MOUNTAINS WILL
ARRIVE AT THE COAST THIS MORNING AND SPREAD TO THE MOUNTAINS BY
AFTERNOON. THE UPPER LEVEL TROUGH WILL LINGER OVER THE WESTERN U.S.
INTO THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS OFFSHORE. THE
RIDGE IS WILL MOVE INLAND BY SUNDAY...BUT IS EXPECTED TO BREAK DOWN
EARLY NEXT WEEK...ALLOWING A PACIFIC COLD FRONT TO MOVE IN.
&&
.SHORT TERM...LEADING SHORTWAVE NOW PUSHING ACROSS CENTRAL VANCOUVER
ISLAND EARLY THIS MORNING. SCATTERED SHOWERS AHEAD OF THIS SYSTEM
ALREADY AFFECTING THE WASHINGTON COAST. EXPECTING SHOWERS TO REACH
THE OREGON COAST SHORTLY. SHOWERS APPROACHING THE COAST ARE BECOMING
MORE ORGANIZED. MODELS ARE SHOWING INCREASING INSTABILITY WITH LIFTED
INDEX JUST AROUND ZERO SO HAVE INCLUDED MENTION OF THUNDERSTORMS OVER
THE NORTHERN MARINE AND COASTAL ZONES THIS MORNING...THEN SPREADING
INLAND OVER THE NORTHERN ZONES FOR THE AFTERNOON AND EARLY EVENING.
SHOWERS SHOULD BE QUITE ACTIVE IN THE AFTERNOON AS THE NEXT SHORTWAVE
DROPS IN. MODEL THICKNESS CHARTS SUPPORT SNOW LEVELS DROPPING TO PASS
LEVELS THIS AFTERNOON AND EVENING AS THE COLD AIR MOVES INTO THE
REGION. THERE APPEARS TO BE SUFFICIENT PRECIPITATION WITH THE
SYSTEM...BRIEFLY ENHANCED BY AN OROGRAPHICALLY FAVORED NW FLOW...TO
YIELD A FEW INCHES OF SNOW IN THE CASCADES...BUT REMAIN BELOW
ADVISORY CRITERIA.
SINCE THIS SYSTEM ORIGINATED AT MUCH HIGHER LATITUDES...IT WILL BE
THE COLDEST SYSTEM TO MOVE INTO THE PACIFIC NORTHWEST SO FAR THIS
FALL SEASON.
MODELS ARE IN REASONABLY GOOD AGREEMENT IN SHOWING THE DEVELOPING
WEST COAST TROUGH TO BE SLOW TO PULL OFF TO THE EAST FRI AND SAT.
SOME LINGERING SHOWERS EXPECTED IN THE CASCADES THROUGH FRI
EVENING. AFTERNOON TEMPERATURES WILL SLOWLY REBOUND FRI AND SAT...BUT
COULD BE A FROSTY NIGHT FRIDAY NIGHT A POSSIBLY SATURDAY NIGHT AS THE
COOL DRY AIR EASILY COOLS UNDER CLEARING SKIES.
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
THE FORECAST AREA REMAINS DRY UNTIL MONDAY AFTERNOON OR EARLY
EVENING. AFTERWARD MODELS BREAK DOWN THE UPPER RIDGE AND ALLOW A
PACIFIC FRONTAL SYSTEM TO SPREAD SOME LIGHT RAIN ACROSS THE REGION.
TRENDED POPS ON MONDAY AND TUESDAY TOWARDS CLIMO. THOUGH CONFIDENCE
DECREASES CONSIDERABLY FROM MONDAY ONWARD...IT APPEARS THAT WE
TRANSITION TO ANOTHER PERIOD OF PROGRESSIVE FLOW AND THUS WET
WEATHER BY TUESDAY. DALTON
&&
.AVIATION...EXPECT SOME LOCAL IFR CONDITIONS EARLY TODAY BEFORE THE
NEXT SYSTEM SPREADS IN. STRATOCUMULUS ALONG THE WEST SLOPES OF THE
CASCADES IS TRYING TO BACK UP OFF THE CASCADES AND WILL LIKELY
ENDING UP GIVING US A MIXTURE OF VFR AND MVFR CIGS AND HURT THE FOG
FORMATION AND KEEP IT FROM BEING TOO WIDESPREAD. THEN CLOUDS FROM
THE NEXT SYSTEM DROPPING OUT OF THE GULF OF ALASKA WILL SPREAD MVFR
CONDITIONS WITH PRECIPITATION ONTO THE COAST AROUND 12Z AND INTERIOR
VALLEYS 15Z TO 18Z. THERE IS A CHANCE OF THUNDERSTORMS ALONG THE
NORTH COAST TODAY...AND INTO THE INTERIOR THIS AFTERNOON. EXPECT
MVFR CONDITIONS TO CONTINUE TONIGHT INTO FRIDAY MORNING UNDER
CONTINUING ONSHORE FLOW BEHIND THE TROUGH WITH COOL SHOWERS. TOLLESON
.KPDX AND APPROACHES...VFR CIGS BACKING OFF THE CASCADES WILL AFFECT
THE AIRPORT EARLY THIS MORNING AND SLOWLY LOWER TO MVFR. A FRONT
WILL MOVE THROUGH MID MORNING THROUGH THE EARLY AFTERNOON AND BRING
MVFR CONDITIONS WITH RAIN OR SHOWERS. A SLIGHT CHANCE OF
THUNDERSTORMS THIS AFTERNOON. SMALL HAIL IS POSSIBLE. MVFR
CONDITIONS WILL LIKELY CONTINUE TONIGHT INTO FRIDAY MORNING. TOLLESON
&&
.MARINE...INCREASING NORTHWEST WINDS WITH THE SYSTEM DROPPING IN
FROM THE GULF OF ALASKA WILL BRING SMALL CRAFT ADVISORY WINDS ACROSS
OUR COASTAL WATERS TODAY AND TONIGHT...DECREASING FRIDAY MORNING.
SEAS WILL REACH ABOVE 10 FEET THIS AFTERNOON AND CONTINUE INTO EARLY
FRIDAY AFTERNOON BEFORE SUBSIDING. THIS WILL CAUSE A ROUGH COLUMBIA
RIVER BAR FOR THE NEXT COUPLE OF EBBS. TOLLESON
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO CASCADE
HEAD TODAY AND TONIGHT.
SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
TODAY THROUGH FRIDAY MORNING.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO FLORENCE THIS AFTERNOON THROUGH FRIDAY.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THIS
AFTERNOON AND TONIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 090955
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
255 AM PDT THU OCT 9 2008
.SHORT TERM...TODAY THROUGH SATURDAY. FREEZE WARNINGS WERE ISSUED
FOR THE OREGON PORTION OF THE LOWER COLUMBIA BASIN AND BLUE MTN
FOOTHILLS. CURRENT TEMPS RANGE FROM 32-37 DEGREES OVER MOST OF THIS
AREA AND TEMPS WILL DECREASE ANOTHER DEGREE OR TWO THIS MORNING. MID
LEVEL CLOUDS ARE STARTING TO INCREASE AHEAD OF AN APPROACHING UPPER
LEVEL TROUGH. WATER VAPOR LOOPS SHOW ENERGY DIVING DOWN THE BACKSIDE
OF THE TROUGH FORCING IT TO ELONGATE OFF THE COAST. A CLOSED LOW
WILL DEVELOP ALONG THE BOTTOM OF THE TROUGH AND OVER THE GREAT BASIN
BY FRIDAY. A NORTHERLY FLOW ALOFT WILL SPREAD COLD AIR THROUGHOUT
EASTERN WA/OR...LOWERING SNOW LEVELS TO NEAR 3500 FEET. SNOW
ACCUMULATIONS WILL BE LIGHT OVER THE EASTERN WASHINGTON ZONES...BUT
FEEL THAT 1-3 INCHES ARE POSSIBLE OVER CENTRAL AND EASTERN OREGON
ABOVE 4000 FEET. THE WRAP-AROUND MOISTURE WILL BE FOCUSED OVER THE
SOUTHERN BLUES AND THE OCHOCO-JOHN DAY HIGHLANDS TONIGHT AND FRIDAY
MORNING. THIS IS THE AREA THAT WILL SEE THE HEAVIEST
ACCUMULATIONS. THIS MEETS EARLY SEASON SNOW ADVISORY CRITERIA FOR
THE OCHOCO-JOHN DAY HIGHLANDS AND WILL ISSUE A WINTER ADVISORY FOR
SNOW TONIGHT THROUGH FRIDAY MORNING.
THE NORTHERLY FLOW ALOFT WILL SPREAD DRIER AIR FROM THE NORTH
TONIGHT AND FRIDAY. BY FRIDAY NIGHT AND SATURDAY...PRECIPITATION
WILL MAINLY BE CONFINED TO THE MOUNTAINS OF UNION, WALLOWA, AND
GRANT COUNTIES WHERE ISOLATED TO SCATTERED SNOW SHOWERS ARE
EXPECTED. IT WILL BE VERY COLD FRIDAY NIGHT...AND FREEZING TEMPS
ARE EXPECTED OVER MOST OF THE FORECAST AREA. AFTERNOON TEMPS ON
FRIDAY AND SATURDAY WILL BE 10-15 DEGREES BELOW NORMAL. A FAIRLY
TIGHT NORTHERLY GRADIENT WILL BRING LOCALLY BREEZY WINDS ON
FRIDAY...MAINLY IN AREAS SOUTH AND EAST OF THE BLUE MOUNTAINS AND
JOHN DAY BASIN. JOHNSON
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...THE UPPER LOW WILL
CONTINUE TO MOVE TO THE EAST WITH A DEEP NORTHERLY FLOW IN ITS WAKE
ON SUNDAY. AT THE SAME TIME AN UPPER RIDGE WILL BE BUILDING OFF THE
COAST. IT WILL BEGIN TO MOVE INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THIS WILL RESULT IN A GRADUAL WARMING TREND WITH A
CONTINUATION OF A DRY PERIOD. NIGHT TIME TEMPERATURE READINGS
HOWEVER WILL CONTINUE TO BE VERY COOL WITH MANY AREAS NEAR FREEZING.
TEMPERATURES WILL BE WARMING A COUPLE DEGREES EACH DAY FROM SUNDAY
THROUGH TUESDAY...WITH NEARLY STEADY TEMPERATURES AFTER TUESDAY.
MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO THROUGH MONDAY AND
THEN BEGIN TO DIVERGE FROM EACH OTHER ON TUESDAY. NEVERTHELESS THE
RIDGE WILL BEGIN TO BREAK DOWN BY TUESDAY MORNING WITH A FASTER
PROGRESSIVE FLOW PATTERN. THE MODELS THEN SHOW GREATER DIFFERENCES
WEDNESDAY AND THURSDAY. DEPENDING ON WHICH MODEL IS CORRECT...THERE
MAY BE EITHER DRY AND WARMER CONDITIONS UNDER AN UPPER RIDGE OR
MARGINALLY DRY BUT COOLER CONDITIONS UNDER A NW FLOW. UNTIL A BETTER
CONSENSUS IS REACHED SIGNIFICANT CHANGES WILL NOT BE MADE AFTER
MONDAY. 88
&&
.AVIATION...MID AND HIGH CLOUDS WILL INCREASE TODAY WITH AN
APPROACHING UPPER TROUGH MOVING INTO THE REGION. CEILINGS WILL
REMAIN ABOVE VFR THROUGH THE DAY AND THEN WILL LOWER FURTHER
TONIGHT. LOCAL MVFR OR IFR CEILINGS MAY DEVELOP TONIGHT WITH RAIN
AND MOUNTAIN SNOW SHOWERS POSSIBLE...ESPECIALLY NEAR KRDM.
VISIBILITIES WILL REMAIN ABOVE 6 NM THROUGH THE DAY BUT MAY DROP TO
MVFR OR IFR AT TIMES IN THE IMMEDIATE VICINITY OF RAIN/SNOW SHOWERS
TONIGHT. WINDS ARE ALSO EXPECTED TO INCREASE TODAY AND TONIGHT WITH
WIND SPEEDS REACHING 15 TO 25 KTS IN THE EASTERN COLUMBIA GORGE AND
10 TO 20 KTS ELSEWHERE THIS AFTERNOON AND EVENING. THE WINDS WILL
THEN DECREASE LATER TONIGHT BACK TO 5 TO 15 KTS IN MOST AREAS. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 56 37 55 32 / 20 30 20 10
ALW 57 39 57 33 / 20 30 10 10
PSC 59 35 59 30 / 20 20 10 0
YKM 58 30 56 28 / 20 20 0 0
HRI 59 35 57 30 / 20 20 10 10
ELN 57 29 56 29 / 20 20 0 0
RDM 50 32 48 25 / 20 40 40 20
LGD 50 33 49 29 / 20 40 40 20
GCD 51 34 49 27 / 20 60 60 20
DLS 58 38 60 32 / 20 30 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM PDT
FRIDAY FOR ORZ505-506.
FREEZE WARNING UNTIL 9 AM PDT THIS MORNING FOR ORZ044-501.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
85/88/88
000
FXUS65 KBOI 090940
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
340 AM MDT THU OCT 9 2008
.SHORT TERM...THE UPPER LEVEL TROUGH THAT WILL BRING COOLER
TEMPERATURES AND THE FIRST CHANCE OF SNOW WAS MOVING INTO WASHINGTON
AND OREGON EARLY THIS MORNING. MODELS A BIT SLOWER ON THE TIMING OF
THE PRECIPITATION MOVING INTO THE AREA AND CURRENT SATELLITE
PICTURES AND RADARS CONFIRM THIS. HAVE BACKED OFF ON POPS FOR THIS
MORNING AND THIS AFTERNOON AND ONLY MADE MINOR CHANGES TO TONIGHT
AND FRIDAY. TEMPERATURES LOOK GOOD BUT DID LOWER A FEW MAX
TEMPERATURES TODAY AS THE COLD AIR BEGINS TO MOVE INTO THE AREA.
MODELS STILL SHOW THE SURFACE PRESSURE GRADIENT TIGHTENING AS THIS
SYSTEM DIGS TO THE SOUTH ALLOWING FOR NEAR ADVISORY LEVEL WINDS THIS
AFTERNOON AND FRIDAY AFTERNOON. AS THE COLDER AIR CONTINUES TO MOVE
INTO THE AREA TONIGHT AND FRIDAY SNOW LEVELS WILL FALL TO VALLEY
FLOORS BY FRIDAY. SNOW AMOUNTS OF UP TO 2 INCHES ARE POSSIBLE
BETWEEN 4000 AND 6000 FEET...AND 2 TO 4 INCHES ABOVE 6000 FEET.
SNOW AMOUNTS JUST BELOW WINTER WEATHER ADVISORY AMOUNTS SO WILL
MENTION IN SPECIAL WEATHER STATEMENT. WILL CONTINUE TO MONITOR THIS
WINTER-LIKE STORM FOR POSSIBLE WINTER WEATHER ADVISORY.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY...STRONG COLD UPPER LOW
WILL REACH ITS SOUTHERNMOST POINT NEAR LAS ABOUT 12Z SATURDAY THEN
TURN BACK NNEWD THROUGH UTAH...THEN WRN WYOMING...THEN OUT OF OUR
AREA LATE SUNDAY. AFTER THAT A HIGH AMPLITUDE UPPER RIDGE WILL COME
IN FROM THE N PACIFIC WITH DRIER AND WARMER AIR. BUT WHILE THE
UPPER LOW IS IN THE GREAT BASIN THIS WEEKEND OUR ZONES...ESPECIALLY
SOUTHERN IDAHO ZONES...WILL BE COLD AND WINDY ALONG WITH A CHANCE OF
SNOW SHOWERS...MIXED WITH RAIN IN THE LOWER VALLEYS. THE WESTERN
MAGIC VALLEY AND SOUTHERN TWIN FALLS COUNTY ARE STILL THE MOST
FAVORED AREAS FOR POSSIBLE ACCUMULATING SNOW FRIDAY EVENING THROUGH
SUNDAY MORNING. THAT IS WHERE MOISTURE WILL WRAP AROUND THE UPPER
LOW AS IT PASSES BY IN UTAH. ALSO...A TIGHT NW-SE SURFACE PRESSURE
GRADIENT WILL CONTINUE GUSTY NW WINDS IN SOUTHERN IDAHO FRIDAY NIGHT
AND SATURDAY...GRADUALLY DECREASING SATURDAY NIGHT AND SUNDAY.
TEMPERATURES THROUGH MONDAY MORNING WILL BE FAR BELOW NORMAL...MAX
TEMPS IN THE UPPER 30S TO LOWER 50S...MIN TEMPS IN THE TEENS TO
LOWER 30S. SEE NEW SPSBOI FOR MORE INFO. TEMPS WILL RECOVER TO
NORMAL BY TUESDAY. ON WEDNESDAY A SHORT WAVE TROUGH WILL REPLACE THE
UPPER RIDGE OF MONDAY AND TUESDAY AND WILL BRING A SLIGHT CHANCE OF
RAIN AND SNOW SHOWERS TO OUR NRN ZONES...AND SEVERAL DEGREES COOLING
TO ALL ZONES.
&&
.AVIATION...WIND IS THE MAIN CONCERN THROUGH FRIDAY. INCREASING
NW-SE SURFACE PRESSURE GRADIENT WILL DEVELOP NW WINDS OF 20-30 KTS
TODAY AND AGAIN FRIDAY. ALOFT A TROUGH/LOW WILL DEVELOP OVER THE
NW STATES AND DIG SSEWD TOWARD NEVADA. VFR TODAY BUT SCATTERED
RAIN/SNOW SHOWERS WILL PRODUCE AREAS OF MVFR CEILING/VISIBILITY
AND LOCAL MOUNTAIN OBSCURATION IN ERN OREGON AND WEST-CENTRAL IDAHO
AFTER 00Z. SHOWERS AND MVFR CONDITIONS WILL SPREAD SEWD TONIGHT AND
FRIDAY. WINDS ALOFT WILL BE MODERATE WLY TODAY...VARIABLE TONIGHT
...THEN MODERATE NELY FRIDAY AS THE UPPER LOW PASSES BY ON ITS WAY
SOUTH INTO NEVADA.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FREEZE WARNING UNTIL 9 AM TODAY FOR IDZ012-IDZ014-IDZ016.
OR...FREEZE WARNING UNTIL 9 AM THURSDAY FOR ORZ064.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...JA
LONG TERM....LC
AVIATION.....LC
000
FXUS66 KMFR 090803
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
103 AM PDT THU OCT 9 2008
.DISCUSSION...00Z NGM/NAM/GFS IN.
SKIES ARE MOSTLY CLEAR OVER MOST OF THE MEDFORD CWA THIS
MORNING...EXCEPT FOR CLOUDS JAMMED UP AGAINST THE WESTERN SLOPES
OF THE CASCADES AND NORTHERN SLOPES OF THE SISKIYOUS...AND SOME
LOW CLOUDS IN THE COQUILLE VALLEY.
HOWEVER...ALL THIS WILL CHANGE LATER TODAY. AN UPPER TROUGH IS NOW
MOVING INTO THE PACIFIC NORTHWEST. INITIALLY THIS TROUGH WILL BE
OF A LOW AMPLITUDE AND DRY...BUT STRONG SHORT WAVES DIVING DOWN
THE BACKSIDE OF THE TROUGH WILL CAUSE IT TO DIG AS IT MOVES
ONSHORE. THE FIRST OF THESE SHORT WAVES WILL BRING SOME LIGHT
PRECIPITATION TO THE AREA BEGINNING LATER THIS MORNING. INITIALLY
IT WILL BE LIMITED TO THE COAST BUT IT WILL SPREAD INLAND TO THE
CASCADES TODAY WITH THE BULK OF THE PRECIPITATION FALLING IN THE
UMPQUA BASIN.
ADDITIONAL SHORT WAVES WILL CAUSE THE UPPER TROUGH TO STOP
PROGRESSING TONIGHT AND IT WILL DIG INTO THE GREAT BASIN TONIGHT
AND FRIDAY...EVENTUALLY PINCHING OFF A CUTOFF LOW OVER NEVADA
FRIDAY. AS THIS OCCURS LIGHT SHOWERS WILL CONTINUE OVER MOST OF
SOUTHWEST AND SOUTH CENTRAL OREGON AS WELL AS EXTREME NORTHERN
CALIFORNIA. FLOW ALOFT WILL BECOME NORTHERLY AND MUCH COOLER AIR
WILL MOVE INTO THE REGION. SNOW LEVELS WILL DROP DOWN TO 3500-4000
FEET THURSDAY NIGHT INTO FRIDAY.
THE SHOWERS WILL END FROM THE WEST FRIDAY EVENING AS THE CUTOFF
LOW CONTINUES SOUTH AND AN UPPER RIDGE LEANS INTO THE CWA.
ACCUMULATIONS WILL BE LESS THAN AN INCH. EXPECT A LOT OF DRYING
FRIDAY NIGHT WITH OFFSHORE LOW LEVEL FLOW. TEMPERATURES WILL DROP
TO NEAR OR BELOW FREEZING FRIDAY NIGHT OVER MOST OF THE MEDFORD
CWA...THE EXCEPTION WILL BE THE COAST...UMPQUA BASIN...AND RIDGES
OVER EXTREME SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY. WILL
ISSUE A FREEZE WATCH LATER THIS MORNING FOR FRIDAY NIGHT.
THE CUTOFF LOW WILL START PROGRESSING EASTWARD AGAIN SATURDAY AND
THIS WILL ALLOW THE OFFSHORE UPPER RIDGE TO MOVE IN. EXPECT
CONTINUED DRY WEATHER WITH A WARMING TREND SATURDAY THROUGH
MONDAY. OFFSHORE LOW LEVEL FLOW WILL PERSIST DURING THE NIGHTTIME
HOURS THROUGH MONDAY NIGHT.
THE RIDGE WILL BREAK DOWN MONDAY AND A LOW AMPLITUDE UPPER TROUGH
WILL PUSH THE NEXT FRONT ONSHORE TUESDAY. DON`T EXPECT MUCH FROM
THIS SYSTEM...IT WILL BE MOVING INTO A VERY DRY AIR MASS. AFTER
THAT A DIRTY RIDGE WILL DEVELOP...AND IT WILL BE STRONG ENOUGH TO
KEEP ANY OTHER SYSTEMS TO THE NORTH OF THE CWA THOUGH NEXT THURSDAY.
&&
AVIATION...MVFR DECKS AND HIGHER MTN OBSCN WILL INCREASE
OVERNIGHT IN ADVANCE OF THE NEXT UPPER LEVEL TROUGH WITH CIGS
FALLING BETWEEN 2-3 KFT BY 12Z THU. RAIN WILL SPREAD INLAND FROM
THE COAST TO THE CASCADES MOSTLY NORTH OF THE UMPQUA DIVIDE THU
WITH WIDESPREAD MTN OBSCN AND SOME REDUCED VSBYS IN -RA/HIGH MTN
SNOW.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...
HAZARDOUS SEAS WARNING UNTIL 2 AM PDT THURSDAY FOR
PZZ356-PZZ376.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT FRIDAY FOR
PZZ350-PZZ370.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 AM PDT SATURDAY FOR
PZZ356-PZZ376.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT FRIDAY
FOR PZZ350-PZZ370.
$$
15/15/05
000
FXUS66 KPDT 090642
AFDPDT
AREA FORECAST DISCUSSION...UPDATED FOR FREEZE WARNING HEADLINE
NATIONAL WEATHER SERVICE PENDLETON OR
1143 PM PDT WED OCT 8 2008
.UPDATE...HAVE ISSUED FREEZE WARNINGS FOR THE OREGON PORTION OF THE
LOWER COLUMBIA BASIN AND THE BLUE MOUNTAIN FOOTHILLS. TEMPERATURES
HAVE FALLEN RAPIDLY IN THE PAST HOUR. WITH DEWPOINTS IN THE MID
20S...FREEZING TEMPS ARE A CERTAINTY BY THURSDAY MORNING. THE
FREEZING TEMPS MAY ONLY LAST ABOUT 2-3 HOURS AS MID LEVEL CLOUDS
BEGIN TO INCREASE ACROSS SE WASHINGTON AND NE OREGON AROUND
SUNRISE. EARLY-MORNING TEMPERATURES IN THE WASHINGTON PORTION OF
THE BASIN AND BLUE MTN FOOTHILLS WILL BE IN THE LOWER TO MID 30S
WITH A FEW LOCATIONS JUST BELOW THE FREEZING MARK. JOHNSON
&&
.AVIATION...06Z TAFS...VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24
HOURS. MID AND HIGH LEVEL CLOUDS WILL GRADUALLY INCREASE OVERNIGHT
AND INTO TOMORROW AHEAD OF AN APPROACHING WEATHER SYSTEM. THIS WILL
BRING A CHANCE OF SHOWERS TO MOST TAF LOCATIONS LATE IN THE
AFTERNOON AND INTO THE EVENING TOMORROW. SURFACE WINDS WILL ALSO
BECOME BREEZY AT KDLS BY TOMORROW AFTERNOON. DMH
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 30 57 37 55 / 0 20 30 20
ALW 36 58 39 57 / 0 20 30 20
PSC 36 60 35 59 / 0 20 20 10
YKM 33 59 30 56 / 0 20 20 0
HRI 29 60 35 57 / 0 20 20 10
ELN 33 58 29 56 / 0 20 20 0
RDM 26 51 32 48 / 0 20 40 30
LGD 31 51 33 49 / 0 20 40 40
GCD 32 52 34 49 / 0 20 50 40
DLS 39 58 38 60 / 0 20 30 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...FREEZE WARNING UNTIL 9 AM PDT THURSDAY FOR ORZ044-501.
WA...NONE.
&&
$$
TI:GYG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
85
000
FXUS66 KPDT 090505 AAA
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1005 PM PDT WED OCT 8 2008
UPDATED AVIATION DISCUSSION
.UPDATE...MOSTLY CLEAR SKIES ARE CURRENTLY OVER THE REGION THIS
EVENING. A TROUGH OF LOW PRESSURE IS APPROACHING THE PACIFIC
NORTHWEST...WITH HIGH LEVEL CLOUDS MOVING ONSHORE. EXPECT THESE
CLOUDS TO MOVE OVER THE AREA TONIGHT AHEAD OF THE SYSTEM. THIS WILL
HELP KEEP OVERNIGHT TEMPERATURES FROM DROPPING BELOW TEMPERATURES
LAST NIGHT. HOWEVER...A FEW ISOLATED POCKETS OF FREEZING
TEMPERATURES ARE POSSIBLE IN LOW-LYING AREAS TONIGHT. CURRENT
FORECAST LOOKS TO BE ON TRACK AND ONLY PLAN TO UPDATE LATER TONIGHT
TO REMOVE EVENING WORDING. DMH
&&
.AVIATION...06Z TAFS...VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24
HOURS. MID AND HIGH LEVEL CLOUDS WILL GRADUALLY INCREASE OVERNIGHT
AND INTO TOMORROW AHEAD OF AN APPROACHING WEATHER SYSTEM. THIS WILL
BRING A CHANCE OF SHOWERS TO MOST TAF LOCATIONS LATE IN THE
AFTERNOON AND INTO THE EVENING TOMORROW. SURFACE WINDS WILL ALSO
BECOME BREEZY AT KDLS BY TOMORROW AFTERNOON. DMH
&&
.PREV DISCUSSION... /ISSUED 145 PM PDT WED OCT 8 2008/
SHORT TERM...TONIGHT THROUGH SATURDAY...REGION IS UNDER A FLAT
WESTERLY FLOW BUT THIS WILL BE CHANGING NEXT 24 HOURS. WEST TO EAST
JET IS BEGINNING TO BUCKLE AS A PIECE OF STORM ENERGY IN THE GULF OF
ALASKA IS STARTING TO DROP SOUTHEAST TOWARDS THE PACIFIC NORTHWEST.
THIS WILL EVENTUALLY LEAD TO THE FORMATION OF A CLOSED LOW MOVING
OVER OREGON THURSDAY NIGHT ON ITS WAY TO THE GREAT BASIN ON FRIDAY.
FORECAST AREA WILL START TO SEE INCREASING SHOWERS EARLY THURSDAY
ACROSS THE WESTERN AREA THEN SPREAD OVER ENTIRE FORECAST AREA BY
AFTERNOON AND EVENING. SNOW LEVELS WILL LOWER THURSDAY NIGHT TO
AROUND 3500 FEET WITH SOME MINOR ACCUMULATIONS POSSIBLE DOWN TO 3000
FEET. WOULD NOT BE SURPRISED TO SEE 1 TO 3 INCH ACCUMULATIONS IN THE
OREGON MOUNTAINS ABOVE 4000 FEET BY FRIDAY MORNING. WILL NEED TO
CONSIDER THE NEED FOR AN EARLY SEASON SNOW ADVISORY BUT WILL HOLD
OFF ON THAT POSSIBILITY UNTIL TOMORROWS FORECAST. BY FRIDAY MOST OF
THE PRECIPITATION WILL BE LIMITED TO OREGON ZONES AND BE DECREASING
OVER TIME. SHOWERS END FOR THE MOST PART ON SATURDAY WITH JUST A
SLIGHT CHANCE OF SHOWERS OVER THE ELKHORN AND WALLOWA MOUNTAINS.
COOLER AIR WILL BE SETTLING OVER THE REGION ASSOCIATED WITH THIS
SYSTEM. CLOUD COVER SHOULD HELP HOLD COLUMBIA BASIN TEMPERATURES
ABOVE FREEZING NEXT COUPLE OF NIGHTS SO NO ADDITIONAL FREEZE
WARNINGS EXPECTED. HOWEVER...THERE WILL BE ISOLATED POCKETS OF
FREEZING TEMPERATURES IN COLD PRONE AREAS TONIGHT. CLEARING SKIES
FRIDAY NIGHT WILL LEAD TO A HIGHER LIKELIHOOD OF A WIDESPREAD FREEZE
OCCURRING IN THE LOWER COLUMBIA BASIN AND SURROUNDING REGIONS.
LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...NORTHERLY FLOW ON
THE BACK SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS
OVER THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. AN UPPER LEVEL
RIDGE WILL MOVE FROM THE COAST TO IDAHO SUNDAY NIGHT AND MONDAY.
SUBSIDENCE FROM THE RIDGE WILL KEEP SKIES MOSTLY CLEAR AND WINDS
LIGHT ALLOWING GOOD RADIATIONAL COOLING AT NIGHT. DURING THE DAY THE
SUBSIDENCE WILL PROVIDE SLOWLY WARMING CONDITIONS. MONDAY NIGHT
THROUGH WEDNESDAY WESTERLY FLOW WITH A COUPLE OF WEAK FAST MOVING
SYSTEMS WILL BE OVER THE PACIFIC NORTHWEST. THESE SYSTEM MAY TRIGGER
A FEW SHOWERS IN THE MOUNTAINS TUESDAY NIGHT OR WEDNESDAY. COONFIELD
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 37 57 37 55 / 0 20 30 20
ALW 38 58 39 57 / 0 20 30 20
PSC 36 60 35 59 / 0 20 20 10
YKM 33 59 30 56 / 0 20 20 0
HRI 34 60 35 57 / 0 20 20 10
ELN 33 58 29 56 / 0 20 20 0
RDM 26 51 32 48 / 0 20 40 30
LGD 31 51 33 49 / 0 20 40 40
GCD 32 52 34 49 / 0 20 50 40
DLS 39 58 38 60 / 0 20 30 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
84
000
FXUS66 KMFR 090400
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
900 PM PDT WED OCT 8 2008
.UPDATE...EVENING UPDATE TO ADJUST SKY GRIDS PER OBSERVED AND
EXPECTED TREND FOR THE REMAINDER OF TONIGHT INTO THURSDAY
MORNING. MOSTLY CLEAR ACROSS THE AREA BUT STRATOCU IS STEADILY
INCREASING ALONG THE WINDWARD SIDE OF THE NORTH CASCADES AND
UMPQUA FOOTHILLS. AS WELL...ACROSS THE SISKIYOU FOREST AROUND THE
COOS-CURRY LINE. EXPECT TO SEE AN INCREASE IN THE WEST SIDE LOW
CLOUD DECK INTO EARLY MORNING AS NEXT FRONT APPROACHES AND JET
SAGS SOUTH OF THE REGION. FAINT CIRRUS STREAK ACROSS THE REGION
AREA SEEN IN SATELLITE IS ASSOCIATED WITH THIS 100+ KT UPPER JET.
FORECAST RAIN TREND FOR THURSDAY LOOKS ON TRACK. STAVISH
&&
.PREV DISCUSSION... /ISSUED 248 PM PDT WED OCT 8 2008/
DISCUSSION...SKIES ARE CLEAR OVER THE CWA THIS AFTERNOON AND WILL
REMAIN CLEAR THROUGH THIS EVENING. A WEAK SHORTWAVE WILL MOVE INTO
THE REGION LATER THIS EVENING...BUT WILL HAVE LITTLE OR NO EFFECT
ON OUR WEATHER. THE NAM...GFS AND ECMWF ALL SHOW AN UPPER LEVEL
TROUGH APPROACHING THE CWA LATE THURSDAY MORNING...THEN MOVING
SOUTHEAST OVER THE CWA THURSDAY AFTERNOON. THIS EVENT WILL BE THE
PRECURSOR FOR THE COLDEST AIR MASS SO FAR THIS SEASON.
PRECIPITATION ASSOCIATED WITH THIS TROUGH WILL INCREASE ALONG THE
COAST THURSDAY MORNING...THEN MOVING INLAND THURSDAY AFTERNOON.
MOST OF THE PRECIPITATION THURSDAY AFTERNOON WILL BE ALONG AND
WEST OF THE CASCADES AND ALSO IN NORTHERN LAKE AND KLAMATH
COUNTIES. WET SNOW SHOWERS WILL BE CONFINED TO ELEVATIONS ABOVE
4000-4500 FEET NORTH AND 4500-5000 FEET SOUTH THURSDAY AFTERNOON
WITH 1000-500 MB THICKNESS LOWERING TO NEAR 534 DM...BUT NO
ACCUMULATION IS EXPECTED.
RAIN SHOWERS WILL CONTINUE THURSDAY NIGHT INTO FRIDAY MORNING
ALONG WITH SNOW SHOWERS OVER THE CASCADES AND MOST OF THE
EAST SIDE. A TRACE TO MAYBE AN INCH SLUSH TOPS COULD ACCUMULATE
ABOVE 5500 FEET ON THE GROUND...BUT ROADS WILL REMAIN WET.
THE MODELS SUGGEST 500MB TEMPERATURES FRIDAY WILL BE NEAR -30C
ALONG AND EAST OF THE CASCADES. THEREFORE THE MAIN FOCUS FOR RAIN
AND WET SNOW SHOWERS WILL BE ALONG AND EAST OF THE CASCADES. ANY
SNOW SHOWERS FRIDAY ARE NOT EXPECTED TO ACCUMULATE.
THE MODELS ARE IN AGREEMENT IN SHOWING THE TROUGH DIGGING TOWARDS
SOUTHERN NEVADA OVERNIGHT FRIDAY INTO SATURDAY MORNING WHICH WILL
LEAVE US IN A NORTH TO NORTHEAST FLOW ALOFT WHICH WILL LEAD TO DRY
CONDITIONS ALONG WITH DECREASING CLOUD COVER. THE AIR MASS WILL BE
THE COLDEST SO FAR THIS SEASON WHICH WILL LEAD TO FREEZING
TEMPERATURES OVER MOST OF THE CWA. AS A RESULT AN SPS HAS BEEN
ISSUED TO COVER FOR THIS. THE SOUTHWEST COAST MAY BE THE ONLY AREA
THAT WILL NOT HAVE FREEZING TEMPERATURES.
THE TROUGH WILL EVOLVE INTO AN UPPER LEVEL LOW SATURDAY MORNING
AND THE LOW IS EXPECTED TO MIGRATE NORTHEAST TOWARDS EASTERN
MONTANA SUNDAY NIGHT. AS THIS HAPPENS...THE RIDGE AXIS WILL SLOWLY
SHIFT EAST JUST WEST OF THE CWA...THEN OVER THE CWA BY THE START
OF NEXT WEEK. THIS WILL RESULT IN MILDER TEMPERATURES DURING THE
DAY AND NIGHT BY THE START OF NEXT WEEK.
&&
.AVIATION...MVFR DECKS AND HIGHER MTN OBSCN WILL INCREASE OVERNIGHT
IN ADVANCE OF THE NEXT UPPER LEVEL TROUGH WITH CIGS FALLING BETWEEN
2-3 KFT BY 12Z THU. RAIN SPREADS INLAND TO THE CASCADES AND SISKIYOUS
THROUGH THU AFTN WITH WIDESPREAD MTN OBSCN AND SOME REDUCED VIS
IN -RA/HIGH MTN SNOW.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...GALE WARNING UNTIL 11 PM PDT THIS EVENING
FOR PZZ356-PZZ376.
HAZARDOUS SEAS WARNING UNTIL 2 AM PDT THURSDAY FOR PZZ356-PZZ376.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 AM PDT FRIDAY FOR PZZ350-
PZZ370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT FRIDAY
FOR PZZ350-PZZ370.
$$
000
FXUS66 KPQR 090329
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
830 PM PDT WED OCT 08 2008
.SYNOPSIS...A TROUGH OF LOW PRESSURE FROM THE GULF OF ALASKA WILL
DROP SOUTHEAST INTO THE PACIFIC NORTHWEST LATER TONIGHT AND THURSDAY
USHERING IN A MUCH COOLER AIR MASS. AN UPPER LEVEL TROUGH WILL LINGER
OVER THE WESTERN U.S. INTO THE WEEKEND AS A RIDGE OF HIGH PRESSURE
BUILDS OFFSHORE. THE RIDGE IS WILL MOVE INLAND BY SUNDAY...BUT IS
EXPECTED TO BREAK DOWN EARLY NEXT WEEK...ALLOWING A PACIFIC COLD
FRONT TO MOVE IN.
&&
.SHORT TERM...SATELLITE IMAGERY SHOWS THE FIRST OF TWO SHORTWAVES
MOVING INTO VANCOUVER ISLAND THIS EVENING WHICH WILL BRING A THREAT
OF LIGHT PRECIPITATION TO THE COASTAL AREAS LATER TONIGHT. A SECOND
SHORTWAVE...WHICH ORIGINATED IN THE GULF OF ALASKA...IS LOCATED OFF
THE NORTHERN BC COAST AND FORECAST TO MOVE SOUTHWARD INTO THE PACIFIC
NORTHWEST ON THURSDAY. THIS SHORTWAVE WILL BRING MORE DYNAMICS AND
COOLER AIR TO THE REGION. AS THIS SHORTWAVE MOVES INTO THE REGION ON
THURSDAY...EXPECT A PERIOD OF FAIRLY WIDESPREAD PRECIPITATION TO
OCCUR BEFORE CHANGING OVER TO CONVECTIVE SHOWERS AS THE COLD AIR
ALOFT SPREADS IN LATER IN THE DAY. SINCE THIS SYSTEM ORIGINATED AT
MUCH HIGHER LATITUDES...IT WILL BE THE COLDEST SYSTEM TO MOVE INTO
THE PACIFIC NORTHWEST SO FAR THIS FALL SEASON. MODEL THICKNESS CHARTS
SUPPORT SNOW LEVELS DROPPING TO PASS LEVELS THURSDAY AFTERNOON AND
EVENING AS THE COLD AIR MOVES INTO THE REGION. THERE APPEARS TO BE
SUFFICIENT PRECIPITATION WITH THE SYSTEM...BRIEFLY ENHANCED BY AN
OROGRAPHICALLY FAVORED NW FLOW...TO YIELD A FEW INCHES OF SNOW IN THE
CASCADES...BUT REMAIN ADVISORY CRITERIA.
MODELS ARE IN REASONABLY GOOD AGREEMENT IN SHOWING THE DEVELOPING
WEST COAST TROUGH TO BE SLOW TO PULL OFF TO THE EAST FRI AND SAT.
SOME LINGERING SHOWERS EXPECTED IN THE CASCADES THROUGH FRI
EVENING. TEMPERATURES WILL SLOWLY REBOUND FRI AND SAT. TW
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
THE FORECAST AREA REMAINS DRY UNTIL MONDAY AFTERNOON OR EARLY
EVENING. AFTERWARD MODELS BREAK DOWN THE UPPER RIDGE AND ALLOW A
PACIFIC FRONTAL SYSTEM TO SPREAD SOME LIGHT RAIN ACROSS THE REGION.
TRENDED POPS ON MONDAY AND TUESDAY TOWARDS CLIMO. THOUGH CONFIDENCE
DECREASES CONSIDERABLY FROM MONDAY ONWARD...IT APPEARS THAT WE
TRANSITION TO ANOTHER PERIOD OF PROGRESSIVE FLOW AND THUS WET
WEATHER BY TUESDAY. DALTON
&&
.AVIATION...WIDESPREAD VFR CONDITIONS OVER THE AREA THIS EVENING
WILL CONTINUE THROUGH TONIGHT. PATCHES OF FOG WILL DEVELOP OVER SOME
INLAND VALLEYS LATER TONIGHT GIVING SOME IFR/LIFR CONDITIONS LATE
TONIGHT AND EARLY THURSDAY. WITH THE NEXT SYSTEM...MVFR CONDITIONS
WILL DEVELOP ALONG THE COAST BY DAYBREAK WITH AREAS OF MVFR SHIFTING
INLAND LATER THURSDAY MORNING AND AFTERNOON. THERE WILL BE LOCAL IFR
THURSDAY MORNING ALONG THE COAST WITH HEAVIER RAIN. THE RAIN WILL
TURN TO SHOWERS OVER INLAND AREAS THURSDAY AFTERNOON. OCCASIONAL
MVFR WITH HEAVIER SHOWERS ARE POSSIBLE THURSDAY AFTERNOON ALONG WITH
SMALL HAIL.
.KPDX AND APPROACHES...VFR CONDITIONS WILL CONTINUE IN THE KPDX AREA
THIS EVENING. PATCHES OF FOG MAY REFORM LATER TONIGHT AND EARLY
THURSDAY MORNING WITH LOCAL IFR CONDITIONS. A PACIFIC FRONT WILL
SPREAD RAIN WITH OCCASIONAL MVFR CONDITIONS INTO THE AREA AFTER
DAYBREAK THURSDAY. LOCAL MVFR CONDITIONS ARE POSSIBLE THURSDAY
AFTERNOON WITH HEAVIER SHOWERS AND SMALL HAIL.
&&
.MARINE...NO CHANGES TO THE FORECAST. HIGH PRESSURE SHIFTS WELL
OFFSHORE TONIGHT AS PACIFIC TROUGH APPROACHES. TROUGH PUSHES ASHORE
THURSDAY MORNING WITH STRONG HIGH PRESSURE WELL OFFSHORE. SMALL
CRAFT WINDS OVER THE CENTRAL COAST THIS EVENING SHOULD BEGIN TO
SLACKEN BRIEFLY OVERNIGHT. SMALL CRAFT WINDS WILL DEVELOP OVER ALL
WATERS THURSDAY BEHIND THE TROUGH. SEAS WILL REMAIN BELOW 10 FEET
TODAY AND TONIGHT THEN BUILD ABOVE 10 FEET THURSDAY AFTERNOON.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
THROUGH MIDNIGHT TONIGHT.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO FLORENCE
THURSDAY AND THURSDAY NIGHT.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO FLORENCE THURSDAY AFTERNOON AND THURSDAY NIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THURSDAY
AFTERNOON AND THURSDAY NIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
Http://weather.gov/portland
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS65 KBOI 090315
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
915 PM MDT WED OCT 8 2008
.DISCUSSION...COLDER AIR BEGINNING TO FILTER INTO SOUTHWEST IDAHO
AHEAD OF MAIN UPPER TROF AND DEVELOPING SYSTEM FOR THURSDAY NIGHT
AND FRIDAY. WINDS HAVE GONE CALM AT ONTARIO AND ARE DIMINISHING
ELSEWHERE. THUS BELIEVE CURRENT FREEZE WARNING IS A GOOD CALL FOR
THE VALLEY...WITH LOWER TREASURE VALLEY LOCATIONS ESPECIALLY PRONE
TO FREEZING OR SLIGHTLY BELOW FREEZING MINS EARLY THURSDAY MORNING.
FREEZE WARNING STARTS AT 2AM MDT AND RUNS THRU 10AM THURSDAY.
MEANWHILE...CLEAR SKIES OVER THE AREA AT THIS TIME AHEAD OF THE
SYSTEM IN THE PACNW WHICH WILL ENHANCE THE POTENTIAL OF FREEZING
TEMPS. BY THURSDAY AFTERNOON THE BIG CHANGE SYSTEM STARTS INTO
EASTERN OREGON THEN SPREADS OVER SOUTHWEST IDAHO TOMORROW EVENING.
SURFACE WINDS WILL INCREASE RAPIDLY BY TOMORROW AFTERNOON BUT RIGHT
NOW A CLOSE CALL JUST BELOW ADVISORY THRESHOLD. THE FORECAST TRENDS
ARE WELL HANDLED AT THIS TIME.
&&
.AVIATION...VFR CONDITIONS WILL CONTINUE TONIGHT THROUGH THURSDAY
MORNING. THURSDAY AFTERNOON AND EVENING LOCAL MVFR CONDITIONS AND
MOUNTAIN OBSCURATION IN RAIN/SNOW SHOWERS WILL DEVELOP ACROSS THE
OREGON ZONES AND WEST CENTRAL IDAHO MOUNTAINS. SNOW LEVELS WILL BE
NEAR 4500 FT. LIGHT SURFACE WINDS TONIGHT WILL INCREASE TO MODERATE/
STRONG NORTHWEST BY 16Z THURSDAY. EXPECT SUSTAINED WINDS 20-25 KTS
WITH GUSTS TO 45 KTS AFTER 18Z. WINDS ALOFT WILL BE LIGHT TO
MODERATE WEST TONIGHT BECOMING MODERATE NORTHWEST THURSDAY.
&&
.PREV DISCUSSION...TONIGHT THROUGH FRIDAY...TURNING COLDER THROUGH
THE PERIOD AS A WINTER-LIKE STORM SYSTEM DEVELOPS OVER THE REGION.
PREFER A BLEND OF THE GFS/ECMWF WHICH ARE IN BETTER AGREEMENT AND
CONSISTENT IN THE TRACK OF UPPER LOW...AS THE NAM TENDS TO TAKE THE
UPPER LOW FURTHER SOUTH THAN THE OTHER MODELS. SFC PRESSURE GRADIENT
TIGHTENS ALONG WITH NORTHWEST WINDS ADVECTING COLDER AIR INTO THE
AREA WILL ALLOW FOR NEAR ADVISORY LEVEL WINDS THURSDAY AFTERNOON...
AND POSSIBLE ADVISORY SPEEDS COME FRIDAY AFTERNOON. BETTER JET
DYNAMICS ON THE WESTERN SIDE OF THE DEVELOPING UPPER LOW WILL BRING
A SHOT OF LIGHT SNOW ACROSS HARNEY COUNTY THURSDAY NIGHT...WITH AN
INCH OR TWO POSSIBLE IN THE VALLEYS AND SEVERAL INCHES IN THE
STEENS. THURSDAY NIGHT INTO FRIDAY...THE NORTH PORTION OF THE UPPER
LOW WILL BE SITUATED OVER THE AREA FOR INCREASED THREAT OF SNOW
SHOWERS AND ACCUMULATING SNOWS ABOVE 4000 FEET. SNOW LEVELS WILL
FALL TO VALLEY FLOORS. ALL TOLD...SNOW AMOUNTS OF UP TO 2 INCHES ARE
POSSIBLE BETWEEN 4000 AND 6000 FEET...AND 2 TO 4 INCHES ABOVE 6000
FEET. MAY EVENTUALLY NEED A WINTER WEATHER ADVISORY FOR PORTIONS OF
SOUTHEAST OREGON/SOUTHWEST IDAHO. STAY TUNED. IN THE MEANTIME...WILL
REFINE THE WORDING IN THE SPECIAL WEATHER STATEMENT.
LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...POTENT UPPER LOW WILL
MAINTAIN ITS HOLD OVER THE INTERMOUNTAIN REGION FRIDAY AND SATURDAY.
MAIN SWATH OF PRECIPITATION WILL BE FOCUSED ON SOUTHWEST IDAHO BY
LATE FRI NIGHT/EARLY SAT MORNING AS UPPER LOW DIGS SOUTH ALONG THE
NV/UT BORDER. ON SATURDAY...UPPER LOW WILL PROGRESS NORTHEAST /INTO
NORTH UT/ WHERE CYCLONIC FLOW AND AMPLE MOISTURE WILL FAVOR UPSLOPE
PRECIPITATION THROUGHOUT THE BOISE MOUNTAINS AND HIGHER TERRAIN OF
TWIN FALLS AND OWYHEE COUNTIES. EXPECT SATURDAY SNOW ACCUMULATIONS
OF 1 TO 4 INCHES BETWEEN 3500 AND 5500 FT. OVERNIGHT LOW
TEMPERATURES STILL FORECAST TO BE AT OR BELOW FREEZING...EVEN
THROUGHOUT LOWEST ELEVATIONS. FRI/SAT HIGH TEMPERATURES WILL AVERAGE
15 TO 17 DEGREES BELOW OCTOBER NORMALS. WINDY CONDITIONS WILL
PERSIST THROUGH SATURDAY NIGHT AS WELL...WITH STRONG SURFACE
GRADIENT GAINING SUPPORT FROM SUBSTANTIAL MID-LEVEL FLOW. EXPECT
CONSIDERABLY DRIER CONDITIONS ON SUNDAY...BUT TEMPERATURES WILL
REMAIN COOL UNDER THE INFLUENCE OF NORTHERLY FLOW ALOFT. A WARMING
TREND WILL BEGIN ON MONDAY AS A HIGHLY AMPLIFIED COASTAL RIDGE
BUILDS INTO THE PACIFIC NORTHWEST.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR IDZ012-IDZ014-
IDZ016.
OR...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR ORZ064.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...GS
PREV DISCUSSION...BW
LONG TERM....MT/DD
AVIATION.....JT
000
FXUS66 KPDT 090304
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
805 PM PDT WED OCT 8 2008
.UPDATE...MOSTLY CLEAR SKIES ARE CURRENTLY OVER THE REGION THIS
EVENING. A TROUGH OF LOW PRESSURE IS APPROACHING THE PACIFIC
NORTHWEST...WITH HIGH LEVEL CLOUDS MOVING ONSHORE. EXPECT THESE
CLOUDS TO MOVE OVER THE AREA TONIGHT AHEAD OF THE SYSTEM. THIS WILL
HELP KEEP OVERNIGHT TEMPERATURES FROM DROPPING BELOW TEMPERATURES
LAST NIGHT. HOWEVER...A FEW ISOLATED POCKETS OF FREEZING
TEMPERATURES ARE POSSIBLE IN LOW-LYING AREAS TONIGHT. CURRENT
FORECAST LOOKS TO BE ON TRACK AND ONLY PLAN TO UPDATE LATER TONIGHT
TO REMOVE EVENING WORDING. DMH
&&
.PREV DISCUSSION... /ISSUED 145 PM PDT WED OCT 8 2008/
SHORT TERM...TONIGHT THROUGH SATURDAY...REGION IS UNDER A FLAT
WESTERLY FLOW BUT THIS WILL BE CHANGING NEXT 24 HOURS. WEST TO EAST
JET IS BEGINNING TO BUCKLE AS A PIECE OF STORM ENERGY IN THE GULF OF
ALASKA IS STARTING TO DROP SOUTHEAST TOWARDS THE PACIFIC NORTHWEST.
THIS WILL EVENTUALLY LEAD TO THE FORMATION OF A CLOSED LOW MOVING
OVER OREGON THURSDAY NIGHT ON ITS WAY TO THE GREAT BASIN ON FRIDAY.
FORECAST AREA WILL START TO SEE INCREASING SHOWERS EARLY THURSDAY
ACROSS THE WESTERN AREA THEN SPREAD OVER ENTIRE FORECAST AREA BY
AFTERNOON AND EVENING. SNOW LEVELS WILL LOWER THURSDAY NIGHT TO
AROUND 3500 FEET WITH SOME MINOR ACCUMULATIONS POSSIBLE DOWN TO 3000
FEET. WOULD NOT BE SURPRISED TO SEE 1 TO 3 INCH ACCUMULATIONS IN THE
OREGON MOUNTAINS ABOVE 4000 FEET BY FRIDAY MORNING. WILL NEED TO
CONSIDER THE NEED FOR AN EARLY SEASON SNOW ADVISORY BUT WILL HOLD
OFF ON THAT POSSIBILITY UNTIL TOMORROWS FORECAST. BY FRIDAY MOST OF
THE PRECIPITATION WILL BE LIMITED TO OREGON ZONES AND BE DECREASING
OVER TIME. SHOWERS END FOR THE MOST PART ON SATURDAY WITH JUST A
SLIGHT CHANCE OF SHOWERS OVER THE ELKHORN AND WALLOWA MOUNTAINS.
COOLER AIR WILL BE SETTLING OVER THE REGION ASSOCIATED WITH THIS
SYSTEM. CLOUD COVER SHOULD HELP HOLD COLUMBIA BASIN TEMPERATURES
ABOVE FREEZING NEXT COUPLE OF NIGHTS SO NO ADDITIONAL FREEZE
WARNINGS EXPECTED. HOWEVER...THERE WILL BE ISOLATED POCKETS OF
FREEZING TEMPERATURES IN COLD PRONE AREAS TONIGHT. CLEARING SKIES
FRIDAY NIGHT WILL LEAD TO A HIGHER LIKELIHOOD OF A WIDESPREAD FREEZE
OCCURRING IN THE LOWER COLUMBIA BASIN AND SURROUNDING REGIONS.
LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...NORTHERLY FLOW ON
THE BACK SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS
OVER THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. AN UPPER LEVEL
RIDGE WILL MOVE FROM THE COAST TO IDAHO SUNDAY NIGHT AND MONDAY.
SUBSIDENCE FROM THE RIDGE WILL KEEP SKIES MOSTLY CLEAR AND WINDS
LIGHT ALLOWING GOOD RADIATIONAL COOLING AT NIGHT. DURING THE DAY THE
SUBSIDENCE WILL PROVIDE SLOWLY WARMING CONDITIONS. MONDAY NIGHT
THROUGH WEDNESDAY WESTERLY FLOW WITH A COUPLE OF WEAK FAST MOVING
SYSTEMS WILL BE OVER THE PACIFIC NORTHWEST. THESE SYSTEM MAY TRIGGER
A FEW SHOWERS IN THE MOUNTAINS TUESDAY NIGHT OR WEDNESDAY. COONFIELD
AVIATION...00Z TAFS...VFR CONDITIONS WITH MOSTLY CLEAR SKIES WILL
PERSIST FOR THE NEXT 24 HOURS. SCATTERED MID AND HIGH CLOUDS WILL
INCREASE FROM THE WEST TONIGHT AS THE NEXT WEATHER SYSTEM BEGINS TO
MOVE INTO THE REGION. CEILINGS WILL BE MAINLY 10-15 KFT AFTER 18Z.
WINDS ARE EXPECTED TO REMAIN BELOW 10 KTS UNTIL 18Z...WITH
INCREASING WINDS IN THE COLUMBIA BASIN AFTER THAT. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 37 57 37 55 / 0 20 30 20
ALW 38 58 39 57 / 0 20 30 20
PSC 36 60 35 59 / 0 20 20 10
YKM 33 59 30 56 / 0 20 20 0
HRI 34 60 35 57 / 0 20 20 10
ELN 33 58 29 56 / 0 20 20 0
RDM 26 51 32 48 / 0 20 40 30
LGD 31 51 33 49 / 0 20 40 40
GCD 32 52 34 49 / 0 20 50 40
DLS 39 58 38 60 / 0 20 30 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
84
000
FXUS66 KPQR 082149
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
248 PM PDT WED OCT 08 2008
.SYNOPSIS...A TROUGH OF LOW PRESSURE FROM THE GULF OF ALASKA WILL
DROP SE INTO THE PACIFIC NORTHWEST TONIGHT AND THU...USHERING IN A
MUCH COOLER AIR MASS. AN UPPER LEVEL TROUGH WILL LINGER OVER THE
WESTERN U.S. INTO THE WEEKEND AS A RIDGE OF HIGH PRESSURE BUILDS
OFFSHORE. THE RIDGE IS WILL MOVE INLAND BY SUN...BUT IS EXPECTED TO
BREAK DOWN EARLY NEXT WEEK...ALLOWING A PACIFIC COLD FRONT TO MOVE
IN.
&&
.SHORT TERM...FIRST SHORTWAVE TO AFFECT AREA IS SEEN ON SATELLITE
PICTURES APPROACHING 130W AT 50N...HEADED TOWARDS THE WA COAST. A
SECOND SHORTWAVE...ORIGINATING IN THE GULF OF ALASKA JUST OFF THE N
BC COAST IS FORECAST BY MODELS TO DROP DOWN INTO THE PACIFIC
NORTHWEST EARLY THU. THE FIRST WAVE SHOULD BRING SOME THREAT OF
PRECIPITATION TO COASTAL AREAS BY LATE TONIGHT...WHILE THE SECOND
SHORTWAVE ADDS MORE DYNAMICS AND COOLER AIR. SATELLITE DOES NOT SHOW
A WELL DEVELOPED FRONT WITH THE THU SHORTWAVE...BUT WITH A WELL
DEFINED SHORTWAVE EXPECT A PERIOD OF FAIRLY WIDESPREAD PRECIPITATION
TO OCCUR BEFORE CHANGING OVER TO CONVECTIVE SHOWERS AS THE COLD AIR
ALOFT SPREADS IN LATER IN THE DAY. WITH HIGH LATITUDE ORIGINS...THIS
IS EASILY THE COLDEST SYSTEM SO FAR THIS FALL TO AFFECT THE
AREA...WITH SNOW LEVELS DROPPING BELOW PASS LEVELS THU. APPEARS TO BE
SUFFICIENT PRECIPITATION WITH THE SYSTEM...BRIEFLY ENHANCED BY AN
OROGRAPHICALLY FAVORED NW FLOW...TO YIELD SEVERAL INCHES OF SNOW FOR
THE CASCADES.
MODELS ARE IN REASONABLY GOOD AGREEMENT IN SHOWING THE DEVELOPING
WEST COAST TROUGH TO BE SLOW TO PULL OFF TO THE E FRI AND SAT. WILL
KEEP A THREAT OF SHOWERS IN FOR THE CASCADES THROUGH FRI
EVENING...WHILE TEMPERATURES RECOVER SLOWLY FRI AND SAT.
.LONG TERM...MODEL KEEP THE FORECAST AREA DRY UNTIL MONDAY AFTERNOON
AND EVENING. AFTERWARD THEY BREAK DOWN THE UPPER RIDGE AND ALLOW A
PACIFIC FRONTAL SYSTEM TO SPREAD SOME LIGHT RAIN ACROSS THE REGION.
TRENDED POPS ON MONDAY AND TUESDAY TOWARDS CLIMO. THOUGH CONFIDENCE
DECREASES CONSIDERABLY FROM MONDAY ONWARD...IT APPEARS THAT WE
TRANSITION TO ANOTHER PERIOD OF PROGRESSIVE FLOW AND THUS WET
WEATHER BY TUESDAY. DALTON
&&
.AVIATION...HIGH PRESSURE OVER WESTERN WASHINGTON THIS AFTERNOON
SHIFTS OFFSHORE TONIGHT AS PACIFIC TROUGH APPROACHES COAST. TROUGH
PUSHES OVER THE AREA THURSDAY MOVING EAST OF THE CASCADES DURING THE
AFTERNOON. VFR CONDITIONS OVER THE AREA THIS AFTERNOON AND EVENING.
IFR/LIFR CONDITIONS. PATCHES OF FOG WILL DEVELOP OVER SOME INLAND
VALLEYS LATER TONIGHT GIVING SOME IFR/LIFR CONDITIONS AND EARLY
THURSDAY. AS THE TROUGH MOVES INTO THE AREA MVFR CONDITIONS WILL
DEVELOP ALONG THE COAST BY DAYBREAK WITH AREAS OF MVFR SHIFTING
INLAND LATER THURSDAY MORNING AND AFTERNOON. THERE WILL BE LOCAL IFR
THURSDAY MORNING ALONG THE COAST WITH HEAVIER RAIN. THE RAIN WILL
TURN TO SHOWERS OVER INLAND AREAS THURSDAY AFTERNOON. OCCASIONAL
MVFR WITH HEAVIER SHOWERS ARE POSSIBLE THURSDAY AFTERNOON ALONG WITH
SMALL HAIL.
.KPDX AND APPROACHES...VFR CONDITIONS IN THE KPDX AREA THIS
AFTERNOON AND EVENING. PATCHES OF FOG MAY REFORM LATER TONIGHT AND
EARLY THURSDAY MORNING WITH LOCAL IFR CONDITIONS. A PACIFIC FRONT
WILL SPREAD RAIN WITH OCCASIONAL MVFR CONDITIONS INTO THE AREA AFTER
DAYBREAK THURSDAY. LOCAL MVFR CONDITIONS ARE POSSIBLE THURSDAY
AFTERNOON WITH HEAVIER SHOWERS AND SMALL HAIL.
&&
.MARINE...HIGH PRESSURE OFFSHORE WITH THERMAL TROUGH OVER NORTHERN
CALIFORNIA THIS AFTERNOON AND EVENING. HIGH PRESSURE SHIFTS WELL
OFFSHORE TONIGHT AS PACIFIC TROUGH APPROACHES. TROUGH PUSHES ASHORE
THURSDAY MORNING WITH STRONG HIGH PRESSURE WELL OFFSHORE. SMALL
CRAFT WINDS WILL DEVELOP OVER THE CENTRAL COAST THIS AFTERNOON AND
CONTINUE INTO THIS EVENING. SMALL CRAFT WINDS WILL DEVELOP OVER ALL
WATERS THURSDAY BEHIND THE TROUGH. SEAS WILL REMAIN BELOW 10 FEET
TODAY AND TONIGHT THEN BUILD ABOVE 10 FEET THURSDAY AFTERNOON.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
THIS AFTERNOON AND EVENING.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO FLORENCE
THURSDAY AND THURSDAY NIGHT.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS CAPE SHOALWATER
TO FLORENCE THURSDAY AFTERNOON AND THURSDAY NIGHT.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA BAR THURSDAY
AFTERNOON AND THURSDAY NIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KMFR 082148
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
248 PM PDT WED OCT 8 2008
.DISCUSSION...SKIES ARE CLEAR OVER THE CWA THIS AFTERNOON AND WILL
REMAIN CLEAR THROUGH THIS EVENING. A WEAK SHORTWAVE WILL MOVE INTO
THE REGION LATER THIS EVENING...BUT WILL HAVE LITTLE OR NO EFFECT
ON OUR WEATHER. THE NAM...GFS AND ECMWF ALL SHOW AN UPPER LEVEL
TROUGH APPROACHING THE CWA LATE THURSDAY MORNING...THEN MOVING
SOUTHEAST OVER THE CWA THURSDAY AFTERNOON. THIS EVENT WILL BE THE
PRECURSOR FOR THE COLDEST AIR MASS SO FAR THIS SEASON.
PRECIPITATION ASSOCIATED WITH THIS TROUGH WILL INCREASE ALONG THE
COAST THURSDAY MORNING...THEN MOVING INLAND THURSDAY AFTERNOON.
MOST OF THE PRECIPITATION THURSDAY AFTERNOON WILL BE ALONG AND
WEST OF THE CASCADES AND ALSO IN NORTHERN LAKE AND KLAMATH
COUNTIES. WET SNOW SHOWERS WILL BE CONFINED TO ELEVATIONS ABOVE
4000-4500 FEET NORTH AND 4500-5000 FEET SOUTH THURSDAY AFTERNOON
WITH 1000-500 MB THICKNESS LOWERING TO NEAR 534 DM...BUT NO
ACCUMULATION IS EXPECTED.
RAIN SHOWERS WILL CONTINUE THURSDAY NIGHT INTO FRIDAY MORNING
ALONG WITH SNOW SHOWERS OVER THE CASCADES AND MOST OF THE
EASTSIDE. A TRACE TO MAYBE AN INCH SLUSH TOPS COULD ACCUMULATE
ABOVE 5500 FEET ON THE GROUND...BUT ROADS WILL REMAIN WET.
THE MODELS SUGGEST 500MB TEMPERATURES FRIDAY WILL BE NEAR -30C
ALONG AND EAST OF THE CASCADES. THEREFORE THE MAIN FOCUS FOR RAIN
AND WET SNOW SHOWERS WILL BE ALONG AND EAST OF THE CASCADES. ANY
SNOW SHOWERS FRIDAY ARE NOT EXPECTED TO ACCUMULATE.
THE MODELS ARE IN AGREEMENT IN SHOWING THE TROUGH DIGGING TOWARDS
SOUTHERN NEVADA OVERNIGHT FRIDAY INTO SATURDAY MORNING WHICH WILL
LEAVE US IN A NORTH TO NORTHEAST FLOW ALOFT WHICH WILL LEAD TO DRY
CONDITIONS ALONG WITH DECREASING CLOUD COVER. THE AIR MASS WILL BE
THE COLDEST SO FAR THIS SEASON WHICH WILL LEAD TO FREEZING
TEMPERATURES OVER MOST OF THE CWA. AS A RESULT AN SPS HAS BEEN
ISSUED TO COVER FOR THIS. THE SOUTHWEST COAST MAY BE THE ONLY AREA
THAT WILL NOT HAVE FREEZING TEMPERATURES.
THE TROUGH WILL EVOLVE INTO AN UPPER LEVEL LOW SATURDAY MORNING
AND THE LOW IS EXPECTED TO MIGRATE NORTHEAST TOWARDS EASTERN
MONTANA SUNDAY NIGHT. AS THIS HAPPENS...THE RIDGE AXIS WILL SLOWLY
SHIFT EAST JUST WEST OF THE CWA...THEN OVER THE CWA BY THE START
OF NEXT WEEK. THIS WILL RESULT IN MILDER TEMPERATURES DURING THE
DAY AND NIGHT BY THE START OF NEXT WEEK.
&&
.AVIATION...SKIES ARE EXPECTED TO REMAIN CLEAR THROUGH THIS
EVENING OVER THE REGION. CLOUDS WILL INCREASE OVERNIGHT TONIGHT IN
ADVANCE OF THE NEXT UPPER LEVEL TROUGH...BUT CIGS SHOULD REMAIN
ABOVE 3000 FEET. SHOWERS WILL INCREASE ALONG THE COAST THURSDAY
MORNING...THEN SPREADING INLAND THURSDAY AFTERNOON. CIGS WILL
LOWER ENOUGH WHERE MTNS WILL OCCASIONALLY BE OBSCURED THURSDAY
AFTERNOON ALONG AND WEST OF THE CASCADES AND SISKIYOUS.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 PM
PDT THIS AFTERNOON FOR PZZ356-PZZ376.
GALE WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ356-PZZ376.
HAZARDOUS SEAS WARNING UNTIL 2 AM PDT THURSDAY FOR PZZ356-PZZ376.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 AM PDT THURSDAY FOR
PZZ350-PZZ370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT FRIDAY
FOR PZZ350-PZZ370.
$$
PETRUCELLI
000
FXUS66 KPDT 082045
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
145 PM PDT WED OCT 8 2008
.SHORT TERM...TONIGHT THROUGH SATURDAY...REGION IS UNDER A FLAT
WESTERLY FLOW BUT THIS WILL BE CHANGING NEXT 24 HOURS. WEST TO EAST
JET IS BEGINNING TO BUCKLE AS A PIECE OF STORM ENERGY IN THE GULF OF
ALASKA IS STARTING TO DROP SOUTHEAST TOWARDS THE PACIFIC NORTHWEST.
THIS WILL EVENTUALLY LEAD TO THE FORMATION OF A CLOSED LOW MOVING
OVER OREGON THURSDAY NIGHT ON ITS WAY TO THE GREAT BASIN ON FRIDAY.
FORECAST AREA WILL START TO SEE INCREASING SHOWERS EARLY THURSDAY
ACROSS THE WESTERN AREA THEN SPREAD OVER ENTIRE FORECAST AREA BY
AFTERNOON AND EVENING. SNOW LEVELS WILL LOWER THURSDAY NIGHT TO
AROUND 3500 FEET WITH SOME MINOR ACCUMULATIONS POSSIBLE DOWN TO 3000
FEET. WOULD NOT BE SURPRISED TO SEE 1 TO 3 INCH ACCUMULATIONS IN THE
OREGON MOUNTAINS ABOVE 4000 FEET BY FRIDAY MORNING. WILL NEED TO
CONSIDER THE NEED FOR AN EARLY SEASON SNOW ADVISORY BUT WILL HOLD
OFF ON THAT POSSIBILITY UNTIL TOMORROWS FORECAST. BY FRIDAY MOST OF
THE PRECIPITATION WILL BE LIMITED TO OREGON ZONES AND BE DECREASING
OVER TIME. SHOWERS END FOR THE MOST PART ON SATURDAY WITH JUST A
SLIGHT CHANCE OF SHOWERS OVER THE ELKHORN AND WALLOWA MOUNTAINS.
COOLER AIR WILL BE SETTLING OVER THE REGION ASSOCIATED WITH THIS
SYSTEM. CLOUD COVER SHOULD HELP HOLD COLUMBIA BASIN TEMPERATURES
ABOVE FREEZING NEXT COUPLE OF NIGHTS SO NO ADDITIONAL FREEZE
WARNINGS EXPECTED. HOWEVER...THERE WILL BE ISOLATED POCKETS OF
FREEZING TEMPERATURES IN COLD PRONE AREAS TONIGHT. CLEARING SKIES
FRIDAY NIGHT WILL LEAD TO A HIGHER LIKELIHOOD OF A WIDESPREAD FREEZE
OCCURRING IN THE LOWER COLUMBIA BASIN AND SURROUNDING REGIONS.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...NORTHERLY FLOW ON
THE BACK SIDE OF AN UPPER LOW WILL KEEP VERY COOL AND DRY CONDITIONS
OVER THE FORECAST AREA SATURDAY NIGHT AND SUNDAY. AN UPPER LEVEL
RIDGE WILL MOVE FROM THE COAST TO IDAHO SUNDAY NIGHT AND MONDAY.
SUBSIDENCE FROM THE RIDGE WILL KEEP SKIES MOSTLY CLEAR AND WINDS
LIGHT ALLOWING GOOD RADIATIONAL COOLING AT NIGHT. DURING THE DAY THE
SUBSIDENCE WILL PROVIDE SLOWLY WARMING CONDITIONS. MONDAY NIGHT
THROUGH WEDNESDAY WESTERLY FLOW WITH A COUPLE OF WEAK FAST MOVING
SYSTEMS WILL BE OVER THE PACIFIC NORTHWEST. THESE SYSTEM MAY TRIGGER
A FEW SHOWERS IN THE MOUNTAINS TUESDAY NIGHT OR WEDNESDAY. COONFIELD
&&
.AVIATION...00Z TAFS...VFR CONDITIONS WITH MOSTLY CLEAR SKIES WILL
PERSIST FOR THE NEXT 24 HOURS. SCATTERED MID AND HIGH CLOUDS WILL
INCREASE FROM THE WEST TONIGHT AS THE NEXT WEATHER SYSTEM BEGINS TO
MOVE INTO THE REGION. CEILINGS WILL BE MAINLY 10-15 KFT AFTER 18Z.
WINDS ARE EXPECTED TO REMAIN BELOW 10 KTS UNTIL 18Z...WITH
INCREASING WINDS IN THE COLUMBIA BASIN AFTER THAT. 76
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 37 57 37 55 / 0 20 30 20
ALW 38 58 39 57 / 0 20 30 20
PSC 36 60 35 59 / 0 20 20 10
YKM 33 59 30 56 / 0 20 20 0
HRI 34 60 35 57 / 0 20 20 10
ELN 33 58 29 56 / 0 20 20 0
RDM 26 51 32 48 / 0 20 40 30
LGD 31 51 33 49 / 0 20 40 40
GCD 32 52 34 49 / 0 20 50 40
DLS 39 58 38 60 / 0 20 30 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
91/76/76
000
FXUS65 KBOI 082037
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
237 PM MDT WED OCT 8 2008
.SHORT TERM...TONIGHT THROUGH FRIDAY...TURNING COLDER THROUGH THE
PERIOD AS A WINTER-LIKE STORM SYSTEM DEVELOPS OVER THE REGION.
PREFER A BLEND OF THE GFS/ECMWF WHICH ARE IN BETTER AGREEMENT AND
CONSISTENT IN THE TRACK OF UPPER LOW...AS THE NAM TENDS TO TAKE THE
UPPER LOW FURTHER SOUTH THAN THE OTHER MODELS. SFC PRESSURE GRADIENT
TIGHTENS ALONG WITH NORTHWEST WINDS ADVECTING COLDER AIR INTO THE
AREA WILL ALLOW FOR NEAR ADVISORY LEVEL WINDS THURSDAY AFTERNOON...
AND POSSIBLE ADVISORY SPEEDS COME FRIDAY AFTERNOON. BETTER JET
DYNAMICS ON THE WESTERN SIDE OF THE DEVELOPING UPPER LOW WILL BRING
A SHOT OF LIGHT SNOW ACROSS HARNEY COUNTY THURSDAY NIGHT...WITH AN
INCH OR TWO POSSIBLE IN THE VALLEYS AND SEVERAL INCHES IN THE
STEENS. THURSDAY NIGHT INTO FRIDAY...THE NORTH PORTION OF THE UPPER
LOW WILL BE SITUATED OVER THE AREA FOR INCREASED THREAT OF SNOW
SHOWERS AND ACCUMULATING SNOWS ABOVE 4000 FEET. SNOW LEVELS WILL
FALL TO VALLEY FLOORS. ALL TOLD...SNOW AMOUNTS OF UP TO 2 INCHES ARE
POSSIBLE BETWEEN 4000 AND 6000 FEET...AND 2 TO 4 INCHES ABOVE 6000
FEET. MAY EVENTUALLY NEED A WINTER WEATHER ADVISORY FOR PORTIONS OF
SOUTHEAST OREGON/SOUTHWEST IDAHO. STAY TUNED. IN THE MEANTIME...WILL
REFINE THE WORDING IN THE SPECIAL WEATHER STATEMENT.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...POTENT UPPER LOW WILL
MAINTAIN ITS HOLD OVER THE INTERMOUNTAIN REGION FRIDAY AND SATURDAY.
MAIN SWATH OF PRECIPITATION WILL BE FOCUSED ON SOUTHWEST IDAHO BY
LATE FRI NIGHT/EARLY SAT MORNING AS UPPER LOW DIGS SOUTH ALONG THE
NV/UT BORDER. ON SATURDAY...UPPER LOW WILL PROGRESS NORTHEAST /INTO
NORTH UT/ WHERE CYCLONIC FLOW AND AMPLE MOISTURE WILL FAVOR UPSLOPE
PRECIPITATION THROUGHOUT THE BOISE MOUNTAINS AND HIGHER TERRAIN OF
TWIN FALLS AND OWYHEE COUNTIES. EXPECT SATURDAY SNOW ACCUMULATIONS
OF 1 TO 4 INCHES BETWEEN 3500 AND 5500 FT. OVERNIGHT LOW
TEMPERATURES STILL FORECAST TO BE AT OR BELOW FREEZING...EVEN
THROUGHOUT LOWEST ELEVATIONS. FRI/SAT HIGH TEMPERATURES WILL AVERAGE
15 TO 17 DEGREES BELOW OCTOBER NORMALS. WINDY CONDITIONS WILL
PERSIST THROUGH SATURDAY NIGHT AS WELL...WITH STRONG SURFACE
GRADIENT GAINING SUPPORT FROM SUBSTANTIAL MID-LEVEL FLOW. EXPECT
CONSIDERABLY DRIER CONDITIONS ON SUNDAY...BUT TEMPERATURES WILL
REMAIN COOL UNDER THE INFLUENCE OF NORTHERLY FLOW ALOFT. A WARMING
TREND WILL BEGIN ON MONDAY AS A HIGHLY AMPLIFIED COASTAL RIDGE
BUILDS INTO THE PACIFIC NORTHWEST.
&&
.AVIATION...WIDESPREAD VFR THROUGH TONIGHT. LIGHT TO MODERATE
SURFACE WINDS WITH LOCALIZED GUSTS TO 25 KTS THIS AFTERNOON AND
EVENING. SURFACE WINDS WILL BECOME LIGHT AFTER 03Z. MODERATE
WESTERLY WINDS ALOFT. THURSDAY...LOCAL MVFR CONDITIONS AND MOUNTAIN
OBSCURATION IN RAIN/SNOW SHOWERS. SNOW LEVELS APPROXIMATELY 4500 FT.
DRASTIC INCREASE IN SURFACE WINDS BY 16Z TOMORROW. EXPECT SUSTAINED
NW WINDS OF 20-25 KTS WITH GUSTS TO 45 KTS AFTER 18Z.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR IDZ012-IDZ014-
IDZ016.
OR...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR ORZ064.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...BW
LONG TERM....MT/DD
AVIATION.....MT
000
FXUS66 KPDT 081719 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1020 AM PDT WED OCT 8 2008
UPDATED AVIATION DISCUSSION
.SHORT TERM...FREEZE WARNINGS HAS BEEN ALLOWED TO EXPIRE THIS
MORNING. WILL LOOK AT THE NEED FOR POSSIBLE FREEZE WARNINGS IN OTHER
LOCATIONS FOR TONIGHT. MOSTLY SUNNY TODAY AS WE AWAIT THE NEXT
WEATHER SYSTEM TO BEGIN MOVING INTO THE AREA TONIGHT. THIS SYSTEM
WILL DIG OUT A DEEP UPPER LEVEL LOW OVER THE PACIFIC NORTHWEST ON
WEDNESDAY AND INTO THURSDAY. THIS WILL LEAD TO SOME COOLER
TEMPERATURES AND INCREASING CHANCE OF PRECIPITATION INTO FRIDAY.
MORE ON THIS IN THE AFTERNOON DISCUSSION.
&&
.AVIATION...VFR CONDITIONS WITH MOSTLY CLEAR SKIES WILL PERSIST FOR
THE NEXT 24 HOURS. SCATTERED MID AND HIGH CLOUDS WILL INCREASE FROM
THE WEST TONIGHT AS THE NEXT WEATHER SYSTEM BEGINS TO MOVE INTO THE
REGION. WINDS ARE EXPECTED TO REMAIN BELOW 10 KTS.
&&
.PREV DISCUSSION... /ISSUED 300 AM PDT WED OCT 8 2008/
SHORT TERM...TODAY THROUGH FRIDAY. A COUPLE OF FORECAST CHALLENGES
ARE IN STORE FOR THE NEXT FEW DAYS. FIRST CHALLENGE WILL BE
OVERNIGHT LOWS THE NEXT COUPLE OF NIGHTS AND WHETHER OUR LOW
ELEVATIONS WILL SEE THE FIRST HARD FREEZE OF THE SEASON. THE FREEZE
WARNINGS CURRENTLY IN EFFECT SHOULD VERIFY EXCEPT FOR THE YAKIMA
VALLEY WHERE TEMPS ARE NOT QUITE AS LOW AS IN THE FORECAST. WILL
CANCEL THE WARNING FOR THE YAKIMA VALLEY. COLDER AND DRIER AIR
BEHIND YESTERDAY`S COLD FRONT WILL RESULT IN DEWPOINTS IN THE TEENS
AND 20S TODAY. IF SKIES WERE CLEAR TONIGHT...THERE WOULD BE NO
DOUBT OF WIDESPREAD FREEZING TEMPS. HOWEVER...CLOUDS WILL BE
INCREASING AHEAD OF A PACIFIC TROUGH WHICH WILL KEEP TEMPS FROM
PLUMMETING. WILL HOLD OFF ON FREEZE WARNINGS TONIGHT AND SEE WHAT
TEMPS AND DEWPOINTS DO THIS MORNING AND AFTERNOON.
THE NEXT CHALLENGE WILL BE HOW LOW SNOW LEVELS WILL FALL AND HOW
MUCH SNOW TO EXPECT OVER THE MOUNTAINS THURS AND THURS NIGHT.
THE PACIFIC TROUGH WILL MOVE ACROSS WA/OR THURSDAY. A FEW WAVES
DIGGING DOWN THE BACKSIDE OF THE TROUGH WILL ALLOW IT TO DIG
SOUTHWARD...RESULTING IN A NORTHERLY FLOW ALOFT THURS NIGHT. SNOW
LEVELS WILL LOWER TO NEAR 3500 FEET...AND EVEN ELEVATIONS DOWN TO
3000 FEET COULD SEE A MIXTURE OF RAIN AND SNOW. THE LOW CLOSES OFF
OVER SE OREGON LATE THURS NIGHT. OROGRAPHIC LIFT AND WRAP-AROUND
MOISTURE COULD RESULT IN ACCUMULATING SNOW...PARTICULARLY IN THE
SOUTHERN BLUE MOUNTAINS...THE WALLOWA MOUNTAINS...AND THE
OCHOCO/JOHN DAY HIGHLANDS. SNOW AMOUNTS COULD REACH EARLY SEASON
ADVISORY CRITERIA. IT IS TOO EARLY TO SAY IF WINTER STATEMENTS ARE
NEEDED AT THIS POINT BUT WILL NEED TO BE CONSIDERED IN THE UPCOMING
SHIFTS. WILL ISSUE A SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE
SITUATION.
WRAP-AROUND PRECIPITATION IS A GOOD POSSIBILITY OVER THE CENTRAL AND
EASTERN OREGON MOUNTAINS ON FRIDAY WHERE THE LOW REMAINS OVER SE
OREGON AND SW IDAHO. AFTERNOON TEMPS ON FRIDAY WILL BE ABOUT 10-15
DEGREES BELOW NORMAL AS THE REGION REMAINS UNDER A NORTHERLY FLOW
ALOFT AND NORTHERLY WINDS AT THE SURFACE. JOHNSON
LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...A DEEP NORTHERLY FLOW
ON THE BACK SIDE OF THE UPPER LOW WILL KEEP VERY COOL CONDITIONS
OVER THE FORECAST AREA THROUGH SATURDAY. THERE WILL BE SOME WRAP
AROUND MOISTURE AROUND THE BACK SIDE OF THE UPPER LOW OVER EXTREME
EASTERN OREGON AND SE WASHINGTON. THIS COMBINED WITH UP SLOPE
TERRAIN EFFECTS WILL CAUSE ISOLATED TO SCATTERED RAIN/HIGHER
ELEVATION SNOW SHOWERS TO CONTINUE FRIDAY NIGHT AND SATURDAY. THE
PRECIP WILL DECREASE SATURDAY AFTERNOON...WITH MORE CLEARING
SATURDAY NIGHT AND SUNDAY AS DRIER AIR MOVES IN BEHIND THE DEPARTING
UPPER LOW. A RIDGE WILL BUILD OVER THE AREA ON SUNDAY BRINGING DRIER
CONDITIONS WITH MOSTLY CLEAR SKIES. EXTENDED RANGE MODELS ARE STILL
IN FAIRLY GOOD AGREEMENT THROUGH TUESDAY. SOME HIGH LEVEL MOISTURE
WILL BE RIDING UP OVER THE RIDGE INTO THE CWA BY MONDAY NIGHT OR
TUESDAY. AT MOST...ONLY SOME MID AND HIGH CLOUDS CAN BE EXPECTED
FROM THIS MOISTURE...OTHERWISE THE DRY CONDITIONS WILL PERSIST. FROM
ABOUT TUESDAY NIGHT INTO WEDNESDAY THE LONG RANGE MODELS DIVERGE
MORE FROM EACH OTHER. HOWEVER THEY ARE FAIRLY CONSISTENT ON A
PROGRESSIVE PATTERN WHICH WILL BRING FAST MOVING WEAK WEATHER
DISTURBANCES ACROSS THE REGION. THESE MAY PRODUCE SOME LIGHT RAIN OR
SNOW SHOWERS OVER THE MOUNTAINS. A GRADUAL WARMING TREND WILL TAKE
PLACE FROM ABOUT SUNDAY ONWARD. 88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 61 36 54 36 / 0 0 20 30
ALW 63 38 56 36 / 0 0 30 30
PSC 66 35 57 34 / 0 0 20 20
YKM 62 31 56 29 / 0 0 20 20
HRI 63 34 57 32 / 0 0 20 20
ELN 62 32 53 30 / 0 0 30 20
RDM 59 26 49 26 / 0 0 20 30
LGD 57 32 48 31 / 0 0 30 40
GCD 60 32 51 28 / 0 0 30 40
DLS 64 39 57 38 / 0 0 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
91/76/76
000
FXUS66 KMFR 081606
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
906 AM PDT WED OCT 8 2008
.DISCUSSION...THE LATEST VIS IMAGERY SHOWS LOW CLOUD COVER IN THE
UMPQUA BASIN AND IN PARTS OF SCOTT AND ILLINOIS VALLEYS. THIS
SHOULD BURN OFF LATER THIS MORNING FOLLOWED BY MOSTLY CLEAR SKIES
FOR THE REST OF THE DAY. A WESTERLY FLOW ALOFT WILL CONTINUE OVER
THE CWA TODAY. MADE A FEW ADJUSTMENTS TO THE SKY COVER THIS
MORNING AND AFTERNOON...OTHERWISE NO OTHER CHANGES WERE MADE. THE
NEXT CONCERN AHEAD IS THE TROUGH THAT IS PROJECTED TO MOVE TOWARDS
THE CWA THURSDAY. THE NAM TRACKS THE TROUGH FURTHER TO THE SOUTH
AND WEST COMPARED TO THE GFS. RIGHT NOW...IT LOOKS LIKE MOST OF
THE PRECIPITATION WILL BE CONFINED TO DOUGLAS COUNTY...NORTH COAST
AND NORTHERN CASCADES LATE THURSDAY MORNING AND AFTERNOON...THEN
SHIFT EAST OF THE CASCADES THURSDAY NIGHT AND FRIDAY. 500MB TEMPS
WILL BE NEAR -30C ALONG AND EAST OF THE CASCADES WHICH WILL HELP
TO MAINTAIN SHOWERS ALONG AND EAST OF THE CASCADES FRIDAY. THE
POTENTIAL FOR ISOLATED THUNDER REMAINS LOW DUE TO COLD AIR AT
ALOFT AND AT THE SURFACE.
&&
.AVIATION...LOW CLOUDS ARE CONFINED TO THE UMPQUA VALLEY AND PARTS
OF THE ILLINOIS VALLEY THIS MORNING...BUT SHOULD BREAK UP WITH
MOSTLY CLEAR SKIES FOR THE AFTERNOON. IFR CONDITIONS WILL PREVAIL
UNTIL AROUND NOON NEAR KRBG...FOLLOWED BY VFR CONDITIONS. ELSEWHERE
VFR CONDITIONS ARE EXPECTED TODAY.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 PM
PDT THIS AFTERNOON FOR PZZ356-PZZ376.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 11 PM PDT THIS EVENING
FOR PZZ356-PZZ376.
HAZARDOUS SEAS WARNING UNTIL 2 AM PDT THURSDAY FOR PZZ356-PZZ376.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 AM PDT THURSDAY FOR
PZZ350-PZZ370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT FRIDAY
FOR PZZ350-PZZ370.
$$
PETRUCELLI
000
FXUS65 KBOI 081600
AFDBOI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
958 AM MDT WED OCT 8 2008
.DISCUSSION...DRY ZONAL FLOW OVER THE AREA TODAY. BOISE MORNING
SOUNDING INDICATES A MAX TEMP OF 63 AT THE BOISE AIRPORT...WHICH IS
OUR FORECASTED HIGH FOR TODAY. DEWPOINTS WILL REMAIN LOW OVERNIGHT
AND WITH A COOL AIRMASS ALREADY IN PLACE...THE FORECAST MINIMUMS FOR
TONIGHT APPEAR TO BE ON TRACK SO WILL UPGRADE THE FREEZE WATCH TO A
WARNING. REMAINDER OF THE FORECAST IS ON TRACK AS WELL.
&&
.AVIATION...WIDESPREAD VFR THROUGH TONIGHT. LIGHT TO MODERATE
SURFACE WINDS WITH GUSTS TO 20 KTS...MAINLY EAST OF MOUNTAIN HOME.
MODERATE TO STRONG WESTERLY WINDS ALOFT. THURSDAY...LOCAL MVFR
CEILINGS IN RAIN/SNOW SHOWERS - SNOW LEVELS APPROXIMATELY 4500 FT.
MOUNTAINS WILL BE OBSCURED. NORTHWEST SURFACE WINDS 25 TO 30 KTS
WITH GUSTS TO 40 KTS.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH THURSDAY...A COOL DRY WESTERLY FLOW OVER
THE REGION TODAY WILL BRING TEMPERATURES TO A FEW DEGREES BELOW
NORMAL COMPARED TO AROUND 5 DEGREES ABOVE NORMAL ON TUESDAY. WITH A
DRY AIRMASS OVER THE REGION AND MOSTLY CLEAR SKIES TONIGHT FORECAST
TEMPERATURES WILL BE IN THE MID 20S TO LOWER 30S IN THE TREASURE AND
WESTERN MAGIC VALLEYS AND IN THE TEENS TO LOWER 20S OVER HIGHER
TERRAIN. WITH THESE UNSEASONABLY COOL TEMPERATURES FOR THURSDAY
MORNING WILL KEEP THE FREEZE WATCH GOING IN THE TREASURE AND WESTERN
MAGIC VALLEYS. THURSDAY THE NEXT UPPER LEVEL TROUGH WILL BEGIN TO
MOVE INTO THE PACIFIC NORTHWEST FOR INCREASING CLOUDS...BRISK
NORTHWEST WINDS...SNOW LEVELS FALLING TO NEAR 4500 FEET AND
TEMPERATURES 10 TO 15 DEGREES BELOW NORMAL.
LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY...A SIGNIFICANT WIND
EVENT IS DEVELOPING FOR FRIDAY AS NW-SE SURFACE PRESSURE GRADIENT
TIGHTENS UNDER THE NW FLANK OF GREAT BASIN UPPER LOW...AS THE LOW
CONTINUES TO DIG SWD THROUGH NEVADA. LATEST MET MOS PREDICTS A HIGH
WIND EVENT AT ONO AND BKE FOR FRIDAY...WITH ADVISORY SPEEDS AT BOI
EUL BNO AND MYL. MAV MOS IS LESS EXTREME BUT BLEND OF THE TWO MOS
STILL CREATES A WIND ADVISORY. SPS WILL BE ISSUED. FRIDAY WILL
ALSO BE COLD DUE TO THE UPPER LOW. WITH ENOUGH MOISTURE AROUND...
PCPN WILL FALL AS SNOW AS LOW AS 3500 FEET FRIDAY...WITH RAIN/SNOW
MIX DOWN TO LOWEST VALLEY FLOORS. NAM SHOWS COLD FRONT AND PCPN
ORIENTED E-W ACROSS SWRN IDAHO FRIDAY MORNING AND SHIFTING SOUTH
THROUGH THE DAY. GFS DOESN/T DEPICT FRONT WELL BUT A COLD FRONT
SHOULD BE NEAR THE NAM POSITION. AFTER THE UPPER LOW SETTLES SOUTH
INTO NEVADA WRAP-AROUND MOISTURE IS PROGGED BY BOTH NAM AND GFS INTO
SCENTRAL IDAHO...INCLUDING TWF AND JER FRIDAY AFTERNOON AND NIGHT.
MET MOS SHOWS MAX TEMPS ONLY IN THE UPPER 30S FRIDAY WHICH COULD
MEAN AN ACCUMULATING SNOWFALL...BUT MAV MOS TEMPS STAY NEAR 50.
ANALOG SCHEME PREDICTS MAX TEMPS IN THE LOWER 40S FRIDAY SO BOTH
RAIN AND SNOW ARE POSSIBLE. WINDY WX WILL CONTINUE INTO SATURDAY AS
UPPER LOW TURNS EWD FROM NEVADA INTO UTAH...AND NW-SE SURFACE
PRESSURE GRADIENT REMAINS TIGHT OVER SRN IDAHO. BY MONDAY THE UPPER
LOW WILL EXIT EAST AND THE NEXT UPSTREAM RIDGE WILL COME IN FROM THE
N PACIFIC WITH WARMER AND DRIER AIR AND LESS WIND. TUE AND WED LOOK
DRY AND MILD UNDER ZONAL FLOW ALOFT.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR IDZ012-IDZ014-
IDZ016.
OR...FREEZE WARNING FROM 2 AM TO 9 AM THURSDAY FOR ORZ064.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...BW
AVIATION.....MT
PREV SHORT TERM...JA
PREV LONG TERM....LC
000
FXUS66 KPQR 081541
AFDPQR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
840 AM PDT WED OCT 08 2008
.SYNOPSIS...A BRISK WESTERLY JET STREAM REMAINED OVER THE PACIFIC
NORTHWEST THIS MORNING. A RATHER COOL SYSTEM WILL APPROACHES TONIGHT
FROM THE GULF OF ALASKA AND THEN MOVE THROUGH SOUTHWEST WASHINGTON
AND NORTHWEST OREGON THURSDAY. HIGH PRESSURE WILL BUILD BACK IN
FRI...AND IS EXPECTED TO CONTINUE THROUGH THE WEEKEND. THE NEXT
CHANCE OF RAIN LOOKS TO BE MONDAY.
&&
.SHORT TERM...RADAR SHOWS THE FEW SHOWERS THAT WERE ACROSS THE N PART
OF THE FORECAST AREA OVERNIGHT HAVE DIMINISHED TO NOT MUCH MORE THAN
ISOLATED SPRINKLES OVER THE S WA CASCADES. SATELLITE AND SURFACE
OBSERVATIONS SHOW A FEW AREAS OF FOG AND LOW CLOUDS THIS MORNING...
MAINLY ALONG THE COLUMBIA RIVER VALLEY AND S OF KEUG. LOW CLOUDS AND
FOG EXPECTED TO BURN OFF THIS MORNING...BUT SLE SOUNDING SUGGESTS
ENOUGH LOW LEVEL MOISTURE REMAINS TO FORM A CU FIELD TODAY. OTHERWISE
NEXT BATCH OF CLOUDS TO MOVE IN SHOULD BE THIS EVENING AS A POORLY
DEFINED VORT MAX SEEN NEAR 48N 138W MOVE ACROSS.
REMAINDER OF SHORT TERM DISCUSSION UNCHANGED...
THE NEXT SYSTEM WILL APPROACH FROM THE GULF OF ALASKA TONIGHT AS THE
UPPER LEVEL FLOW BUCKLES AND AMPLIFIES. THE LOW LEVEL FLOW WILL TURN
ONSHORE AND CLOUDS WILL INCREASE TONIGHT AND EARLY THURSDAY.
PRECIPITATION WITH THIS SYSTEM WILL SPREAD THROUGH OUR FORECAST AREA
THURSDAY. SNOW LEVELS WILL LOWER TO BELOW PASS ELEVATIONS THURSDAY...
AND POSSIBLY APPROACH 2000 FEET THURSDAY NIGHT. PRECIPITATION AMOUNTS
WILL BE A BIT LIMITED SO EXPECT ACCUMULATIONS TO REMAIN BELOW
ADVISORY CRITERIA...THOUGH THE PASSES THROUGH THE CASCADES COULD SEE
2 OR 3 INCHES THURSDAY AFTERNOON AND THURSDAY NIGHT. TEMPS THURSDAY
AT LOW ELEVATIONS WILL LIKELY HAVE TROUBLE GETTING PAST THE MID 50S.
THE SYSTEM DEVELOPS INTO AN UPPER LOW IN NORTHERN NEVADA FRIDAY...BUT
A FEW SHOWERS WILL LIKELY LINGER NEAR THE CASCADES FROM THE FLOW
AROUND THE BACK SIDE OF THE LOW. THE REMAINDER OF THE AREA SHOULD SEE
DECREASING CLOUDS...THOUGH THE AIR MASS REMAINS COOL AND TEMPS WILL
HAVE TROUBLE REACHING 60. TOLLESON
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...
MODELS CUTOFF AN UPPER LOW OVER THE GREAT BASIN ON SATURDAY...FORCING
A STRONG AND SHARP UPPER LEVEL RIDGE TO DEVELOP OVER THE NORTHEAST
PACIFIC AND INTO BRITISH COLUMBIA. THIS WOULD PROVE TO BE NICE FALL
WEATHER FOR THE FORECAST AREA OVER THE WEEKEND. MODELS THEN KICK THE
CLOSED LOW OFF TO THE EAST AND ALLOW PACIFIC SYSTEM TO SWING THROUGH
BY MONDAY AFTERNOON. MODELS ALL AGREE ON THIS GENERAL SOLUTION FOR
NOW...SO FORECAST REFLECTS THIS CONFIDENCE. DALTON
&&
.AVIATION...HIGH PRESSURE OVER THE AREA THIS MORNING BUILDS INTO
WESTERN WASHINGTON THIS AFTERNOON. HIGH PRESSURE SHIFTS OFFSHORE
TONIGHT AS PACIFIC TROUGH APPROACHES COAST. THERE AREA AREAS OF FOG
AND STRATUS OVER THE INLAND VALLEYS AND ALONG THE COLUMBIA RIVER
THIS MORNING. THIS IS GIVING AREAS OF IFR/LIFR CONDITIONS. ALL FOG
AND STRATUS WILL CLEAR BY MIDDAY WITH VFR CONDITIONS OVER THE AREA
THIS AFTERNOON. PATCHES OF FOG WILL DEVELOP OVER SOME INLAND VALLEYS
LATER TONIGHT GIVING SOME IFR/LIFR CONDITIONS.
.KPDX AND APPROACHES...AREAS OF STRATUS AND PATCHY FOG MAINLY FROM
KPDX WEST THIS MORNING WILL CLEAR BY LATE MORNING. VFR CONDITIONS IN
THE KPDX AREA THIS AFTERNOON AND THIS EVENING. PATCHES OF FOG MAY
REFORM LATER TONIGHT WITH LOCAL IFR CONDITIONS.
&&
.MARINE...HIGH PRESSURE OFFSHORE WITH THERMAL TROUGH OVER NORTHERN
CALIFORNIA THIS AFTERNOON AND EVENING. SMALL CRAFT WINDS WILL
DEVELOP OVER THE CENTRAL COAST THIS AFTERNOON AND CONTINUE INTO THIS
EVENING. SEAS WILL REMAIN BELOW 10 FEET TODAY AND TONIGHT.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR/WA...SMALL CRAFT ADVISORY FOR WINDS CASCADE HEAD TO FLORENCE
THIS AFTERNOON AND EVENING.
SMALL CRAFT ADVISORY FOR WINDS CAPE SHOALWATER TO FLORENCE
THURSDAY AND THURSDAY NIGHT.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
000
FXUS66 KPDT 081530
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
826 AM PDT WED OCT 8 2008
.SHORT TERM...FREEZE WARNINGS HAS BEEN ALLOWED TO EXPIRE THIS
MORNING. WILL LOOK AT THE NEED FOR POSSIBLE FREEZE WARNINGS IN OTHER
LOCATIONS FOR TONIGHT. MOSTLY SUNNY TODAY AS WE AWAIT THE NEXT
WEATHER SYSTEM TO BEGIN MOVING INTO THE AREA TONIGHT. THIS SYSTEM
WILL DIG OUT A DEEP UPPER LEVEL LOW OVER THE PACIFIC NORTHWEST ON
WEDNESDAY AND INTO THURSDAY. THIS WILL LEAD TO SOME COOLER
TEMPERATURES AND INCREASING CHANCE OF PRECIPITATION INTO FRIDAY.
MORE ON THIS IN THE AFTERNOON DISCUSSION.
&&
.PREV DISCUSSION... /ISSUED 300 AM PDT WED OCT 8 2008/
SHORT TERM...TODAY THROUGH FRIDAY. A COUPLE OF FORECAST CHALLENGES
ARE IN STORE FOR THE NEXT FEW DAYS. FIRST CHALLENGE WILL BE
OVERNIGHT LOWS THE NEXT COUPLE OF NIGHTS AND WHETHER OUR LOW
ELEVATIONS WILL SEE THE FIRST HARD FREEZE OF THE SEASON. THE FREEZE
WARNINGS CURRENTLY IN EFFECT SHOULD VERIFY EXCEPT FOR THE YAKIMA
VALLEY WHERE TEMPS ARE NOT QUITE AS LOW AS IN THE FORECAST. WILL
CANCEL THE WARNING FOR THE YAKIMA VALLEY. COLDER AND DRIER AIR
BEHIND YESTERDAY`S COLD FRONT WILL RESULT IN DEWPOINTS IN THE TEENS
AND 20S TODAY. IF SKIES WERE CLEAR TONIGHT...THERE WOULD BE NO
DOUBT OF WIDESPREAD FREEZING TEMPS. HOWEVER...CLOUDS WILL BE
INCREASING AHEAD OF A PACIFIC TROUGH WHICH WILL KEEP TEMPS FROM
PLUMMETING. WILL HOLD OFF ON FREEZE WARNINGS TONIGHT AND SEE WHAT
TEMPS AND DEWPOINTS DO THIS MORNING AND AFTERNOON.
THE NEXT CHALLENGE WILL BE HOW LOW SNOW LEVELS WILL FALL AND HOW
MUCH SNOW TO EXPECT OVER THE MOUNTAINS THURS AND THURS NIGHT.
THE PACIFIC TROUGH WILL MOVE ACROSS WA/OR THURSDAY. A FEW WAVES
DIGGING DOWN THE BACKSIDE OF THE TROUGH WILL ALLOW IT TO DIG
SOUTHWARD...RESULTING IN A NORTHERLY FLOW ALOFT THURS NIGHT. SNOW
LEVELS WILL LOWER TO NEAR 3500 FEET...AND EVEN ELEVATIONS DOWN TO
3000 FEET COULD SEE A MIXTURE OF RAIN AND SNOW. THE LOW CLOSES OFF
OVER SE OREGON LATE THURS NIGHT. OROGRAPHIC LIFT AND WRAP-AROUND
MOISTURE COULD RESULT IN ACCUMULATING SNOW...PARTICULARLY IN THE
SOUTHERN BLUE MOUNTAINS...THE WALLOWA MOUNTAINS...AND THE
OCHOCO/JOHN DAY HIGHLANDS. SNOW AMOUNTS COULD REACH EARLY SEASON
ADVISORY CRITERIA. IT IS TOO EARLY TO SAY IF WINTER STATEMENTS ARE
NEEDED AT THIS POINT BUT WILL NEED TO BE CONSIDERED IN THE UPCOMING
SHIFTS. WILL ISSUE A SPECIAL WEATHER STATEMENT TO HIGHLIGHT THE
SITUATION.
WRAP-AROUND PRECIPITATION IS A GOOD POSSIBILITY OVER THE CENTRAL AND
EASTERN OREGON MOUNTAINS ON FRIDAY WHERE THE LOW REMAINS OVER SE
OREGON AND SW IDAHO. AFTERNOON TEMPS ON FRIDAY WILL BE ABOUT 10-15
DEGREES BELOW NORMAL AS THE REGION REMAINS UNDER A NORTHERLY FLOW
ALOFT AND NORTHERLY WINDS AT THE SURFACE. JOHNSON
LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...A DEEP NORTHERLY FLOW
ON THE BACK SIDE OF THE UPPER LOW WILL KEEP VERY COOL CONDITIONS
OVER THE FORECAST AREA THROUGH SATURDAY. THERE WILL BE SOME WRAP
AROUND MOISTURE AROUND THE BACK SIDE OF THE UPPER LOW OVER EXTREME
EASTERN OREGON AND SE WASHINGTON. THIS COMBINED WITH UP SLOPE
TERRAIN EFFECTS WILL CAUSE ISOLATED TO SCATTERED RAIN/HIGHER
ELEVATION SNOW SHOWERS TO CONTINUE FRIDAY NIGHT AND SATURDAY. THE
PRECIP WILL DECREASE SATURDAY AFTERNOON...WITH MORE CLEARING
SATURDAY NIGHT AND SUNDAY AS DRIER AIR MOVES IN BEHIND THE DEPARTING
UPPER LOW. A RIDGE WILL BUILD OVER THE AREA ON SUNDAY BRINGING DRIER
CONDITIONS WITH MOSTLY CLEAR SKIES. EXTENDED RANGE MODELS ARE STILL
IN FAIRLY GOOD AGREEMENT THROUGH TUESDAY. SOME HIGH LEVEL MOISTURE
WILL BE RIDING UP OVER THE RIDGE INTO THE CWA BY MONDAY NIGHT OR
TUESDAY. AT MOST...ONLY SOME MID AND HIGH CLOUDS CAN BE EXPECTED
FROM THIS MOISTURE...OTHERWISE THE DRY CONDITIONS WILL PERSIST. FROM
ABOUT TUESDAY NIGHT INTO WEDNESDAY THE LONG RANGE MODELS DIVERGE
MORE FROM EACH OTHER. HOWEVER THEY ARE FAIRLY CONSISTENT ON A
PROGRESSIVE PATTERN WHICH WILL BRING FAST MOVING WEAK WEATHER
DISTURBANCES ACROSS THE REGION. THESE MAY PRODUCE SOME LIGHT RAIN OR
SNOW SHOWERS OVER THE MOUNTAINS. A GRADUAL WARMING TREND WILL TAKE
PLACE FROM ABOUT SUNDAY ONWARD. 88
AVIATION...VFR CONDITIONS WITH MOSTLY CLEAR SKIES WILL PERSIST
TODAY. MID AND HIGH CLOUDS WILL INCREASE FROM THE WEST TONIGHT AS
THE NEXT WEATHER SYSTEM BEGINS TO MOVE INTO THE REGION. HOWEVER...
CEILINGS WILL REMAIN ABOVE 12K FEET THROUGH WEDNESDAY NIGHT. WINDS
ARE ALSO EXPECTED TO REMAIN LIGHT AND BELOW 10 KTS THROUGH TONIGHT.
88
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 61 36 54 36 / 0 0 20 30
ALW 63 38 56 36 / 0 0 30 30
PSC 66 35 57 34 / 0 0 20 20
YKM 62 31 56 29 / 0 0 20 20
HRI 63 34 57 32 / 0 0 20 20
ELN 62 32 53 30 / 0 0 30 20
RDM 59 26 49 26 / 0 0 20 30
LGD 57 32 48 31 / 0 0 30 40
GCD 60 32 51 28 / 0 0 30 40
DLS 64 39 57 38 / 0 0 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
$$
TI:GGG
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
91/76/76
| 
