000
FXUS06 KWBC 202000
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS, MD
300 PM EST TUE JAN 20 2009
6-10 DAY OUTLOOK FOR JAN 26 - 30 2009
TODAYS ENSEMBLE MEAN SOLUTIONS ARE IN GOOD AGREEMENT ON THE EXPECTED 500-HPA
CIRCULATION PATTERN FOR THE 6-10 DAY PERIOD OVER NORTH AMERICA. MOST MODELS SHOW
A ZONAL FLOW OVER THE CONUS. A RIDGE IS FORECAST OVER THE NORTH PACIFIC OCEAN.
TODAYS BLEND CHART INDICATES NORMAL TO BELOW NORMAL HEIGHTS ACROSS MOST OF THE
WESTERN AND NORTHERN CONUS, WHILE ABOVE NORMAL HEIGHTS ARE EXPECTED OVER THE
SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY AND SOUTHEAST. THIS PATTERN SUPPORTS
NORMAL TO BELOW NORMAL TEMPERATURES FOR THE WESTERN THIRD OF THE CONUS, THE
ALASKAN PANHANDLE, THE NORTHERN PLAINS, THE UPPER MISSISSIPPI VALLEY AND NEW
ENGLAND. ABOVE-NORMAL TEMPERATURES ARE FORECAST ACROSS THE SOUTHERN PLAINS,
LOWER MISSISSIPPI VALLEY AND SOUTHEAST. MOST MODELS PREDICT ABOVE MEDIAN
PRECIPITATION FOR THE GREAT BASIN, NORTHERN AND CENTRAL ROCKIES, OHIO VALLEY
AND TENNESSEE VALLEY. THE SOUTHERN PLAINS, FLORIDA, SOUTHERN ALASKA AND THE
ALASKAN PANHANDLE ARE EXPECTED TO HAVE BELOW MEDIAN PRECIPITATION DURING THIS
FORECAST PERIOD.
TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY`S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...10 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON
DAY 8...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15
PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...40 PERCENT OF
TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...AND 10 PERCENT OF TODAY`S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8.
MODEL OF THE DAY: GFS SUPERENSEMBLE MEAN
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: AVERAGE, 3 ON A SCALE OF 1 TO 5,
DUE TO GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS, BUT ZONAL FLOW ACROSS
THE CONUS.
THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE AUTO BLEND TEMPERATURE FORECAST,
THE KLEIN, NEURAL NET, AND ANALOG TEMPERATURE SPECIFICATIONS FROM THE MANUAL
BLEND, KLEIN SPECIFICATIONS FROM THE ENSEMBLE MEAN SOLUTIONS, THE CDC
TEMPERATURE FORECAST, AND THE NAEFS TEMPERATURE FORECAST.
THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE NAEFS PRECIPITATION FORECAST,
THE AUTO BLEND PRECIPITATION FORECAST, THE CDC PRECIPITATION FORECAST, AND
ANALOG SPECIFICATIONS BASED ON THE MANUAL BLEND.
8-14 DAY OUTLOOK FOR JAN 28 - FEB 03, 2009
FOR WEEK 2 THE MODELS ARE VERY SIMILAR TO THEIR RESPECTIVE SOLUTIONS FOR THE 6
TO 10 DAY PERIOD. ZONAL FLOW WILL DOMINATE MOST OF THE CONUS. MOST MODELS
PREDICT NEAR TO BELOW NORMAL TEMPERATURES FOR THE WESTERN HALF OF THE CONUS AND
MOST OF ALASKA, WITH ABOVE NORMAL TEMPERATURES OVER THE EASTERN HALF OF CONUS.
ABOVE MEDIAN PRECIPITATION IS EXPECTED OVER THE PACIFIC NORTHEAST, NORTHERN
GREAT BASIN, TENNESSEE VALLEY, OHIO VALLEY AND PARTS OF THE GREAT LAKES. BELOW
MEDIAN PRECIPITATION IS FORECAST OVER THE SOUTHERN AND CENTRAL PLAINS, FLORIDA
AND MOST OF ALASKA.
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 10 PERCENT OF TODAY`S OPERATIONAL
0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY`S OPERATIONAL 6Z GFS CENTERED
ON DAY 11...15 PERCENT OF TODAY`S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...15
PERCENT OF TODAY`S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...40 PERCENT OF
TODAY`S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 10 PERCENT OF TODAY`S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: AVERAGE, 3 ON A SCALE OF 1 TO
5, DUE TO GOOD AGREEMENT AMONG THE ENSEMBLE MEAN SOLUTIONS, BUT ZONAL FLOW
ACROSS THE CONUS.
THE 8-14 DAY TEMPERATURE PROG IS BASED ON: KLEIN, NEURAL NETWORK, AND ANALOG
SPECIFICATIONS BASED ON THE MANUAL BLEND, THE AUTO BLEND TEMPERATURE FORECAST,
THE KLEIN SPECIFICATIONS FROM THE GFS-BASED MODELS, AND THE NAEFS TEMPERATURE
FORECAST.
THE 8-14 DAY PRECIPITATION PROG IS BASED ON: NEURAL NETWORK AND ANALOG
PRECIPITATION SPECIFICATIONS FROM THE MANUAL BLEND, THE NAEFS PRECIPITATION
FORECAST, THE AUTO BLEND PRECIPITATION FORECAST, THE CDC PRECIPITATION TOOL,
AND THE ANALOG PRECIPITATION TOOL FROM THE GFS ENSEMBLE MEANS.
FORECASTER: LUKE HE
NOTES:
OPERATIONAL CHANGE: AS OF JULY 5 2005 SHADED MAPS HAVE REPLACED THE
CONTOUR-ONLY MAPS ON THE CPC WEB SITE. THE CONTOURED MAPS ARE
STILL AVAILABLE AT THEIR CURRENT FILE NAMES - SO DIRECT-LINKED USERS
ARE NOT AFFECTED. AWIPS GRAPHICS ARE ALSO NOT AFFECTED BY THIS
CHANGE.
AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OTHERWISE -
FORECASTS INCORPORATE FORECASTER INPUT.
THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS
THE SAME AS THAT IN THE TABLES: A-ABOVE N-NEAR NORMAL B-BELOW
IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL
BE A GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY
EVEN A NORMAL (I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY
SEASONS. IN SUCH CASES A FORECAST OF NEAR NORMAL IS EFFECTIVELY A
FORECAST OF LITTLE OR NO PRECIPITATION.
THE NARRATIVE DESCRIPTION OF THE FORECAST PATTERNS FOR TEMPERATURE
AND PRECIPITATION FOR BOTH THE 6-10 OR 8-14 DAY PERIODS HAS BEEN
DISCONTINUED. THE STATE TABLES FOR BOTH THE 6-10 AND 8-14 DAY
PERIODS ARE NOW CONTAINED IN THIS MESSAGE...AVAILABLE AS PMDMRD ON
AWIPS.
THE CLIMATE PREDICTION CENTER USES 1971-2000 BASE PERIOD MEANS FOR
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN
THE CLIMATE OUTLOOKS.
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON
FEBRUARY 19.
NEW NOTE EFFECTIVE MAR 16 2004:
THE GLOSSARY FORMERLY FOUND AT THIS LOCATION WILL NO LONGER BE TRANSMITTED AS
PART OF THIS MESSAGE. IF YOU WISH TO SEE THE DEFINITIONS OF TERMS USED IN THESE
MESSAGES... PLEASE GO TO THE CPC WEB PAGE AT (USE LOWER CASE)
HTTP://WWW.CPC.NCEP.NOAA.GOV AND FOLLOW THE APPROPRIATE LINKS.
ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19650116 - 19610120 - 19810103 - 19810201 - 19760201
ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19650116 - 19610120 - 19760201 - 19810202 - 19810103
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 26 - 30 2009
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B N OREGON B N NRN CALIF B N
SRN CALIF B N IDAHO B A NEVADA B A
W MONTANA B A E MONTANA B A WYOMING B A
UTAH B A ARIZONA B N COLORADO N N
NEW MEXICO N N N DAKOTA B N S DAKOTA B N
NEBRASKA N N KANSAS N N OKLAHOMA N N
N TEXAS A B S TEXAS A B W TEXAS A B
MINNESOTA N N IOWA N N MISSOURI N N
ARKANSAS N N LOUISIANA A N WISCONSIN N N
ILLINOIS N N MISSISSIPPI A N MICHIGAN N N
INDIANA N N OHIO N N KENTUCKY N A
TENNESSEE N A ALABAMA A N NEW YORK N N
VERMONT N N NEW HAMP B N MAINE B N
MASS N N CONN N N RHODE IS N N
PENN N N NEW JERSEY N N W VIRGINIA N N
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A B AK N SLOPE A N
AK ALEUTIAN N N AK WESTERN A N AK INT BSN N N
AK S INT N B AK SO COAST N B AK PNHDL B B
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR JAN 28 - FEB 03, 2009
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B A NRN CALIF B N
SRN CALIF B N IDAHO B N NEVADA B N
W MONTANA B N E MONTANA N N WYOMING N N
UTAH B N ARIZONA B N COLORADO N N
NEW MEXICO N B N DAKOTA N N S DAKOTA N N
NEBRASKA N B KANSAS N B OKLAHOMA A B
N TEXAS A B S TEXAS A B W TEXAS N B
MINNESOTA N N IOWA N N MISSOURI A N
ARKANSAS A N LOUISIANA A N WISCONSIN A N
ILLINOIS A A MISSISSIPPI A N MICHIGAN A N
INDIANA A A OHIO A A KENTUCKY A A
TENNESSEE A A ALABAMA A N NEW YORK A N
VERMONT A N NEW HAMP A N MAINE N N
MASS A N CONN A N RHODE IS A N
PENN A N NEW JERSEY A N W VIRGINIA A N
MARYLAND A N DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA A N GEORGIA A N
FL PNHDL A N FL PENIN A B AK N SLOPE B B
AK ALEUTIAN N N AK WESTERN N N AK INT BSN B B
AK S INT B B AK SO COAST B B AK PNHDL B N
LEGEND
TEMPS WITH RESPECT TO NORMAL PCPN WITH RESPECT TO MEDIAN
A - ABOVE N - NEAR NORMAL A - ABOVE N - NEAR MEDIAN
B - BELOW B - BELOW
THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.
FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.
$$
000
FXUS01 KWBC 201914
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
213 PM EST TUE JAN 20 2009
VALID 00Z WED JAN 21 2009 - 12Z THU JAN 22 2009
A QUIET PERIOD IS EXPECTED ACROSS THE EASTERN U.S. AS THE SYSTEM
CURRENTLY OFF OF THE SOUTHERN MID ATLANTIC COAST MOVES FURTHER OUT
SEA EARLY IN THE PERIOD. WITH THE EXCEPTION OF SOME LAKE EFFECT
SNOW SHOWERS DOWNWIND OF THE OF THE GREAT LAKES AND SOME UPSLOPE
SNOWS IN THE CENTRAL APPALACHIANS...DRY CONDITIONS ARE EXPECTED
ACROSS THE EASTERN HALF OF THE U.S. THROUGH THE SHORT-TERM PERIOD.
TEMPERATURES WILL REMAIN COLD FOR THE NEXT DAY BEFORE A BRIEF
WARMING TREND RETURNS TEMPERATURES TO SEASONAL OR ABOVE AVERAGE
ACROSS MUCH OF THE EAST.
ACROSS THE GREAT PLAINS AND ROCKIES...TEMPERATURES WILL RUN ABOVE
AVERAGE THROUGH WEDNESDAY AS LOW LEVEL WINDS TURN
WESTERLY...CAUSING DOWNSLOPING AND WARMING...BEFORE THE NEXT SURGE
OF ARCTIC AIR DIVES SOUTH...PLUNGES THROUGH THE NORTHERN AND
CENTRAL PLAINS ON THURSDAY.
OUT WEST...AN UPPER LEVEL DISTURBANCE AND WEAK SURFACE
FRONT...WILL SLOWLY APPROACH CALIFORNIA OVER THE NEXT COUPLE OF
DAYS. THERE ARE SOME DIFFERENCES IN THE TIMING OF THE ASSOCIATED
WET WEATHER...BUT IT APPEARS LIGHT RAIN WILL REACH THE CENTRAL AND
SOUTHERN COAST OF CALIFORNIA BY THE LATTER HALF OF WEDNESDAY...
WITH STEADIER PRECIPITATION POSSIBLE BY THURSDAY MORNING.
PEREIRA
GRAPHICS AVAILABLE AT WWW.HPC.NCEP.NOAA.GOV
$$
000
FXUS02 KWBC 201853
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
152 PM EST TUE JAN 20 2009
VALID 12Z FRI JAN 23 2009 - 12Z TUE JAN 27 2009
MULTI-DAY MEANS FROM 00Z GFS/ECMWF/GEFS MEAN RUNS DEPICT TWO
SIGNIFICANT HGT ANOMALY CENTERS THAT SHOULD HAVE AN INFLUENCE ON
NORTH AMERICAN FLOW BY THE LATTER HALF OF THE FCST PERIOD. OVER
THE PAC A STRONG POSITIVE ANOMALY CENTER IS FCST APPROXIMATELY
BETWEEN ALASKA AND HAWAII. TELECONNECTIONS RELATIVE TO THIS
FEATURE FAVOR A FAIRLY DEEP TROF WITH AN AXIS SOMEWHERE OVER THE
INTERIOR WEST OR PAC NW COAST DEPENDING ON THE POSN OF THE
UPSTREAM RIDGE. MEANWHILE A STRONG NEGATIVE HGT ANOMALY EXPECTED
OVER THE NERN ATLC TELECONNECTS TO A BROAD MEAN TROF ORIENTED OVER
E-CNTRL NOAM... WITH ABOVE OR WELL ABOVE NORMAL HGTS FROM THE EAST
COAST INTO THE WRN ATLC.
GUIDANCE IS STILL HAVING DIFFICULTIES IN HANDLING FLOW OVER
ALASKA/NWRN CANADA IN THE SHORT RANGE SO THERE REMAINS SOME
UNCERTAINTY IN THE FCST AS OF DAY 3 FRI. 00Z/06Z GFS RUNS ARE
ONCE AGAIN MORE RELUCTANT TO CLOSE OFF AN UPPER HIGH OVER OR NEAR
THE NRN AK COAST VERSUS MOST OTHER GUIDANCE... SO THEIR SOLNS ARE
CONSIDERED AMONG THE LESS LIKELY ONES ACROSS SRN CANADA AND NRN
CONUS LATE THIS WEEK INTO THE WEEKEND. THERE IS STILL FAIR
AGREEMENT THAT STRENGTHENING OF THE ERN PAC RIDGE SHOULD ENCOURAGE
DEVELOPMENT OF A TROF OVER THE WEST BY AROUND DAY 5 SUN. 00Z/06Z
GFS RUNS MAY BE BRINGING TOO MUCH SWRN CANADA ENERGY INTO THE NWRN
STATES DUE TO ISSUES EARLIER IN THE PERIOD.
MODEL AND ENSEMBLE SPREAD SHOWS A MORE DRAMATIC INCREASE BY DAYS
6-7 MON-TUE. WHAT AGREEMENT THAT DOES EXIST AMONG 00Z
GEFS/ECMWF/CANADIAN ENSEMBLES WOULD INDICATE THAT UPSTREAM PAC
FLOW SHOULD APPROACH THE WEST COAST EARLIER THAN FCST BY 00Z/06Z
GFS RUNS... THUS KICKING THE WRN CONUS TROF EWD FASTER THAN THE
GFS. THIS IS REFLECTED IN THE 00Z GEFS MEAN WHOSE TROF AXIS IS
FAIRLY CLOSE TO THE 00Z ECMWF AND SLIGHTLY FASTER 12Z/19 EC RUNS
THAT ARE OVER THE PLAINS AS OF EARLY DAY 7 TUE. 00Z ECMWF
ENSEMBLE MEAN PROGRESSION IS AT LEAST AS FAST AS THE 12Z/19 EC.
AS OF EARLY TUE INDIVIDUAL GEFS/EC/CMC ENSEMBLE MEMBERS SHOW NO
WELL DEFINED CLUSTERING OF SFC WAVES... WITH A FAIRLY EVEN
SCATTERING FROM THE SRN HALF OF THE PLAINS TO THE ERN SLOPES OF
THE CNTRL-SRN APLCHNS.
12Z UPDATE... THE NEW GFS RUN APPEARS TO HAVE RESOLVED SOME OF ITS
PROBLEMS OVER NWRN NOAM IN THE SHORT RANGE. HOWEVER WHILE THE 12Z
GFS IS NOT AN OUTLIER AMONG 12Z GEFS MEMBERS IT IS FAIRLY EXTREME
WITH THE AMPLITUDE OF ITS TROF THAT DIGS INTO THE SOUTHWEST BY
EARLY NEXT WEEK... AND IS MUCH DEEPER THAN THE GEFS MEAN WHICH BY
DAY 7 BEARS A CLOSE RESEMBLANCE TO THE 00Z ECMWF ENS MEAN. BY
SUN-MON THE 12Z UKMET/CMC BRING CNTRL CONUS LOW PRESSURE FARTHER
NWD THAN MOST OTHER GUIDANCE IN RESPONSE TO DIFFERING DETAILS
ALOFT. WILL NOT GIVE MUCH WEIGHT TO THOSE SOLNS GIVEN THEIR
VERIFICATION HISTORY AND COLD AIR IN PLACE OVER THE NRN HALF-TWO
THIRDS OF THE CONUS.
EVOLUTION OF ECMWF RUNS AND VARIOUS ENSEMBLE MEANS OVER THE ERN
PAC/WRN CONUS LATE IN THE FCST PERIOD AND JUST BEYOND SEEMS TO GO
ALONG WITH ERN PAC/WRN NOAM TELECONNECTIONS BETTER THAN
OPERATIONAL GFS RUNS... WHILE A COMPROMISE AMONG THE
ECMWF/ENSEMBLE MEANS SHOULD PROVIDE A REASONABLE COMPROMISE FOR
RESOLVING VERY UNCERTAIN TIMING DIFFS OVER THE CNTRL-ERN CONUS.
THUS THE DAYS 6-7 MON-TUE FCST STARTS WITH A 50/30/20 BLEND OF THE
00Z ECMWF/00Z GEFS MEAN/00Z EC ENS MEAN. DAY 7 WAS ADJUSTED TO A
00Z EC AND 12Z/19 EC COMPROMISE TO ARRIVE AT AN INTERMEDIATE
FRONTAL POSN OVER THE ERN HALF OF THE CONUS. THE 12Z GEFS MEAN
SUPPORTS A SIMILAR DAY 7 POSN. A 70/30 BLEND OF THE 00Z EC/EC
MEAN... WITH MINOR ADJUSTMENT TO ACCOUNT FOR 12Z GUIDANCE DAYS
3-4... PROVIDES A FAIR REPRESENTATION OF CONSENSUS WITH THE DAYS
3-5 FRI-SUN FCST THAT IS DOMINATED BY COLD HIGH PRESSURE BUILDING
INTO THE CNTRL-ERN STATES AND THE LEADING LOW PRESSURE/COLD FRONT.
REGIONAL HIGHLIGHTS...
...WEST...
EXPECT PERIODS OF RAIN AND HIGH ELEV SNOW MOSTLY ACROSS CNTRL-NRN
AREAS FRI-TUE. THIS ACTIVITY MAY BE FAIRLY PERSISTENT AT SOME
LOCATIONS BUT SHOULD BE OF ONLY LGT-MDT INTENSITY. NRN-CNTRL
AREAS SHOULD ALSO SEE A MODEST COOLING TREND OVER THE COURSE OF
THE FCST PERIOD WITH A GRADUAL DECLINE IN SNOW LEVELS.
...CENTRAL/EAST...
LOW PRESSURE TRACKING INTO THE NORTHEAST FRI-SAT AND COLD FRONT
TRAILING INTO THE SRN PLAINS WILL BE AT THE LEADING EDGE OF
ANOTHER AREA OF COLD HIGH PRESSURE THAT SHOULD SUPPORT BELOW TO
WELL BELOW NORMAL TEMPS OVER MANY AREAS OVER THE NRN HALF OF THE
CNTRL-ERN CONUS THRU THE WEEKEND AND INTO EARLY NEXT WEEK. BY
SUN-TUE PACIFIC AND EVENTUALLY SOME GULF MOISTURE SHOULD BEGIN TO
STREAM OVER THIS DOME OF COLD AIR... LEADING TO A BROADENING
SHIELD OF WINTRY PCPN FROM THE CNTRL PLAINS TO EAST COAST WITH
RAIN POSSIBLE OVER THE SOUTH. IT WILL LIKELY TAKE A WHILE TO
RESOLVE DETAILS OF COVERAGE/TIMING/INTENSITY OF THE VARIOUS PCPN
TYPES.
RAUSCH
$$
000
FXUS01 KWBC 200851
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
350 AM EST TUE JAN 20 2009
VALID 12Z TUE JAN 20 2009 - 00Z THU JAN 22 2009
AS AN AREA OF LOW PRESSURE MOVES AWAY FROM THE COAST OF THE
CAROLINAS TODAY... RAIN WILL CHANGE TO SNOW FROM WEST TO EAST
EARLY THIS MORNING ACROSS THE CENTRAL EAST COAST. THE SNOW IS
EXPECTED TO LINGER ACROSS EASTERN NORTH CAROLINA AND SOUTHEASTERN
VIRGINIA THROUGH MUCH OF TODAY... LEAVING BEHIND A BROAD AREA OF
TWO TO FOUR INCHES WITH ISOLATED HIGHER TOTALS ACROSS THE REGION.
FARTHER NORTH... LIGHT LAKE EFFECT SNOW SHOWERS WILL CONTINUE TO
THE SOUTH AND EAST OF THE GREAT LAKES... ALONG WITH SOME LIGHT
UPSLOPE SNOW INTO THE CENTRAL APPALACHIANS... WITH ANY
ACCUMULATIONS STAYING ON THE LIGHT SIDE. TODAY WILL BE A COLD DAY
ACROSS THE EASTERN PORTION OF THE COUNTRY AS A COLD FRONT MOVES
FARTHER INTO THE ATLANTIC... WITH HIGHS ONLY IN THE 20S AND 30S
FROM PORTIONS OF THE NORTHEAST DOWN INTO THE CAROLINAS.
TEMPERATURES SHOULD ONLY REACH THE TEENS FROM MICHIGAN AND
NORTHERN OHIO INTO NORTHERN NEW ENGLAND.
AS A BROAD UPPER LEVEL TROUGH BEGINS TO LIFT SOMEWHAT FOR
WEDNESDAY AND THURSDAY OVER THE EAST... IT WILL WARM ACROSS THE
REGION... WITH TEMPERATURES RETURNING CLOSE TO SLIGHTLY ABOVE
AVERAGE FOR AREAS EAST OF THE MISSISSIPPI. WEST OF THE MISSISSIPPI
AND INTO THE ROCKIES... TEMPERATURES WILL RUN ABOVE AVERAGE
THROUGH THURSDAY AS LOW LEVEL WINDS TURN WESTERLY... CAUSING
DOWNSLOPING AND WARMING. THIS WILL ESPECIALLY BE TRUE ACROSS THE
SOUTHERN AND CENTRAL HIGH PLAINS WHERE HIGH TEMPERATURES SHOULD
RUN WELL INTO THE 60S. IT WILL ALSO BE WARM ACROSS PORTIONS OF
CENTRAL AND EASTERN MONTANA TODAY AND WEDNESDAY... BEFORE A SURGE
OF ARCTIC AIR DIVES SOUTH... REACHING THE U.S.-CANADIAN BORDER
EARLY ON THURSDAY.
OUT WEST... AN UPPER LEVEL DISTURBANCE... AND WEAK SURFACE
FRONT... WILL SLOWLY APPROACH CALIFORNIA OVER THE NEXT COUPLE OF
DAYS. THERE ARE SOME DIFFERENCES IN THE TIMING OF THE ASSOCIATED
WET WEATHER... BUT IT APPEARS LIGHT RAIN WILL REACH THE CENTRAL
COAST OF CALIFORNIA WEDNESDAY MORNING... WITH STEADIER
PRECIPITATION MOVING IN BY EVENING.
OTHER THAN THE AREAS MENTIONED ABOVE... AND SOME LOWER ELEVATION
FOG FOR THE NORTHWEST... THE REST OF THE COUNTRY WILL STAY DRY
THROUGH WEDNESDAY AS MOISTURE IS VERY LIMITED OVER THE LOWER 48.
OTTO
GRAPHICS AVAILABLE AT WWW.HPC.NCEP.NOAA.GOV
$$
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