000
FXUS63 KLMK 201746
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1240 PM EST TUE JAN 20 2009
.NEAR TERM (THIS AFTERNOON)...
UPDATED TO CHANGE THE FLURRY ACTIVITY WORDING TO OCCASIONAL AND ALSO
LOWER TEMPS A BIT WITH LOW CLOUDS EXPECTED TO LINGER INTO MOST OF
THE AFTN. FLURRIES COULD PUT DOWN A THIN LAYER OF SNOW ON THE LESSER
TRAVELED ROADS...WITH POTENTIAL FOR SLICK SPOTS...PUT OUT A SPECIAL
WEATHER STATEMENT TO ADDRESS THAT.
.SHORT TERM (TODAY AND TONIGHT)...
COLD NORTHWEST FLOW TO PERSIST FOR ANOTHER DAY WITH A LITTLE WAVE
ENERGY AND WEAK WARM AIR ADVECTION ALOFT TO POTENTIALLY AID IN THE
DEVELOPMENT OF SOME FLURRIES ACROSS THE CWA THE FIRST HALF OF TODAY.
WITH LITTLE GOING ON NOW IN SIMILAR AIR MASS AND LITTLE ADDITIONAL
UPSTREAM MOISTURE TO WORK WITH...WOULD NOT EXPECT TOO MUCH IF ANY
FLURRIES TO OCCUR BUT CANNOT RULE THEM OUT ENTIRELY. BEST SHOT
THROUGH EARLY AFTERNOON WOULD BE IN THE NORTHEASTERN ZONES WHERE THE
BEST WARM AID ADVECTION IS PROGGED TO BE...SO WILL PUT SLIGHTLY
HIGHER POPS THERE...BUT NOT ENOUGH TO MENTION ANYTHING OTHER THAN
FLURRIES AT THIS TIME.
TEMPERATURES WILL STRUGGLE TODAY TO REACH THE UPPER 20S...ESPECIALLY
IN AREAS WITH A LITTLE MORE SNOW COVER. TONIGHT SKIES WILL BEGIN TO
CLEAR AND TEMPERATURES WILL FALL ONCE AGAIN INTO THE TEENS FOR MOST
LOCATIONS...THOUGH SOME ISOLATED LOWER 20S MAY OCCUR IN THE
SOUTHWEST.
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
WEDNESDAY THROUGH FRIDAY...
THE EXCEPTIONALLY AMPLIFIED WESTERN RIDGE/EASTERN TROUGH PATTERN
THAT HAS PERSISTED FOR A WEEK WILL FINALLY BREAK DOWN WEDNESDAY AS
PACIFIC ENERGY WILL ATTEMPT TO UNDERCUT THE BLOCKING 500MB RIDGE
ACROSS THE NORTHERN ROCKIES. A SPLIT FLOW PATTERN WILL DEVELOP
ACROSS THE WESTERN CONUS BY EARLY SATURDAY...AS THE SOUTHERN JET
FORMS ACROSS THE SOUTHWESTERN CONUS AND MEETS THE NORTHERN JET ON
THE EASTERN SIDE OF THIS SPLIT IN CONFLUENT FLOW ACROSS THE MIDWEST.
TRANQUIL WEATHER WITH PARTLY CLOUDY SKIES AND WARMING TEMPERATURES
ARE EXPECTED WEDNESDAY THROUGH FRIDAY. THE PERSISTENT TROUGH ACROSS
THE EASTERN CONUS WILL BEGIN TO EASE AND MOVE FARTHER EAST ACROSS
NEW ENGLAND. 500MB HEIGHTS WILL BEGIN TO RISE ACROSS THE LOWER OHIO
VALLEY BEGINNING WEDNESDAY.
AT THE SURFACE...THE AXIS OF A HIGH PRESSURE RIDGE WILL MOVE ACROSS
KENTUCKY EARLY WEDNESDAY. SOUTHWESTERLY FLOW WILL BEGIN WEDNESDAY
AND CONTINUE THROUGH FRIDAY AFTERNOON. AFTER A COLD START EARLY
WEDNESDAY...AFTERNOON TEMPERATURES WILL RISE 7 TO 10 DEGREES EACH
DAY THROUGH THURSDAY...MOST LIKELY REACHING THE MID TO UPPER 40S
THURSDAY AFTERNOON.
WITH NORTHWEST FLOW ALOFT AND SURFACE RIDGING ACROSS THE GULF
COAST...LITTLE MOISTURE WILL RETURN. EXPECT QUITE A BIT OF SUN MIXED
IN WITH SOME PASSING MID LEVEL CLOUDS THROUGH FRIDAY AFTERNOON.
SATURDAY THROUGH MONDAY...
A SHALLOW ARCTIC AIRMASS BUILDING IN CANADA WILL MOVE SOUTH INTO
THE UPPER MIDWEST THURSDAY. AS A SHORTWAVE MOVES ACROSS THE GREAT
LAKES FRIDAY SOME OF THIS COLD AIR WILL ARRIVE LATE FRIDAY. UNLIKE
THE PAST SEVERAL ARCTIC INTRUSIONS...A SOUTHWESTERLY FLOW ALOFT WILL
LIMIT THE SOUTHWARD PENETRATION OF THE COLDEST OF THIS AIR. STILL
THOUGH...TEMPERATURES SHOULD SIGNIFICANTLY COOL THIS WEEKEND.
A LACK OF MOISTURE BE AN ISSUE THIS WEEKEND...SO EXPECT LITTLE MORE
THAN JUST A SLIGHT CHANCE OF LIGHT RAIN OR FLURRIES FRIDAY INTO
SATURDAY.
FORECAST MODELS STILL SUGGEST A POSSIBILITY OF MIXED PRECIPITATION
DEVELOPING MONDAY. OVERRUNNING PRECIPITATION WILL LIKELY DEVELOP
ACROSS THE LOWER OHIO VALLEY NORTH OF A FRONTAL BOUNDARY WHICH WILL
LIKELY SET UP ACROSS TENNESSEE. ARCTIC AIR WILL REMAIN CLOSE BY TO
OUR NORTH.
&&
.AVIATION (18Z TAFS)...
COLD NLY FLOW WILL PERSIST THROUGH TONIGHT...HOWEVER WINDS WILL
SHIFT TO SW WED. OCCASIONAL FLURRIES WILL CONTINUE MUCH OF THE AFTN
INTO THE EARLY EVE...LOWERING VSBY TO MVFR FOR BRIEF PERIODS OF
TIME...MAINLY FOR THE LEX AND SDF TAF. BKN TO OVC MVFR LOW CIGS SHUD
BECOME SCTD TNGT AS HIGH PRES BUILDS IN FROM THE SW.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
NEAR TERM....DK
SHORT TERM...MACZKO
LONG TERM....JSD
AVIATION.....11
000
FXUS63 KLMK 201653
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1150 AM EST TUE JAN 20 2009
.NEAR TERM (THIS AFTERNOON)...
UPDATED TO CHANGE THE FLURRY ACTIVITY WORDING TO OCCASIONAL AND ALSO
LOWER TEMPS A BIT WITH LOW CLOUDS EXPECTED TO LINGER INTO MOST OF
THE AFTN. FLURRIES COULD PUT DOWN A THIN LAYER OF SNOW ON THE LESSER
TRAVELED ROADS...WITH POTENTIAL FOR SLICK SPOTS...PUT OUT A SPECIAL
WEATHER STATEMENT TO ADDRESS THAT.
.SHORT TERM (TODAY AND TONIGHT)...
COLD NORTHWEST FLOW TO PERSIST FOR ANOTHER DAY WITH A LITTLE WAVE
ENERGY AND WEAK WARM AIR ADVECTION ALOFT TO POTENTIALLY AID IN THE
DEVELOPMENT OF SOME FLURRIES ACROSS THE CWA THE FIRST HALF OF TODAY.
WITH LITTLE GOING ON NOW IN SIMILAR AIR MASS AND LITTLE ADDITIONAL
UPSTREAM MOISTURE TO WORK WITH...WOULD NOT EXPECT TOO MUCH IF ANY
FLURRIES TO OCCUR BUT CANNOT RULE THEM OUT ENTIRELY. BEST SHOT
THROUGH EARLY AFTERNOON WOULD BE IN THE NORTHEASTERN ZONES WHERE THE
BEST WARM AID ADVECTION IS PROGGED TO BE...SO WILL PUT SLIGHTLY
HIGHER POPS THERE...BUT NOT ENOUGH TO MENTION ANYTHING OTHER THAN
FLURRIES AT THIS TIME.
TEMPERATURES WILL STRUGGLE TODAY TO REACH THE UPPER 20S...ESPECIALLY
IN AREAS WITH A LITTLE MORE SNOW COVER. TONIGHT SKIES WILL BEGIN TO
CLEAR AND TEMPERATURES WILL FALL ONCE AGAIN INTO THE TEENS FOR MOST
LOCATIONS...THOUGH SOME ISOLATED LOWER 20S MAY OCCUR IN THE
SOUTHWEST.
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
WEDNESDAY THROUGH FRIDAY...
THE EXCEPTIONALLY AMPLIFIED WESTERN RIDGE/EASTERN TROUGH PATTERN
THAT HAS PERSISTED FOR A WEEK WILL FINALLY BREAK DOWN WEDNESDAY AS
PACIFIC ENERGY WILL ATTEMPT TO UNDERCUT THE BLOCKING 500MB RIDGE
ACROSS THE NORTHERN ROCKIES. A SPLIT FLOW PATTERN WILL DEVELOP
ACROSS THE WESTERN CONUS BY EARLY SATURDAY...AS THE SOUTHERN JET
FORMS ACROSS THE SOUTHWESTERN CONUS AND MEETS THE NORTHERN JET ON
THE EASTERN SIDE OF THIS SPLIT IN CONFLUENT FLOW ACROSS THE MIDWEST.
TRANQUIL WEATHER WITH PARTLY CLOUDY SKIES AND WARMING TEMPERATURES
ARE EXPECTED WEDNESDAY THROUGH FRIDAY. THE PERSISTENT TROUGH ACROSS
THE EASTERN CONUS WILL BEGIN TO EASE AND MOVE FARTHER EAST ACROSS
NEW ENGLAND. 500MB HEIGHTS WILL BEGIN TO RISE ACROSS THE LOWER OHIO
VALLEY BEGINNING WEDNESDAY.
AT THE SURFACE...THE AXIS OF A HIGH PRESSURE RIDGE WILL MOVE ACROSS
KENTUCKY EARLY WEDNESDAY. SOUTHWESTERLY FLOW WILL BEGIN WEDNESDAY
AND CONTINUE THROUGH FRIDAY AFTERNOON. AFTER A COLD START EARLY
WEDNESDAY...AFTERNOON TEMPERATURES WILL RISE 7 TO 10 DEGREES EACH
DAY THROUGH THURSDAY...MOST LIKELY REACHING THE MID TO UPPER 40S
THURSDAY AFTERNOON.
WITH NORTHWEST FLOW ALOFT AND SURFACE RIDGING ACROSS THE GULF
COAST...LITTLE MOISTURE WILL RETURN. EXPECT QUITE A BIT OF SUN MIXED
IN WITH SOME PASSING MID LEVEL CLOUDS THROUGH FRIDAY AFTERNOON.
SATURDAY THROUGH MONDAY...
A SHALLOW ARCTIC AIRMASS BUILDING IN CANADA WILL MOVE SOUTH INTO
THE UPPER MIDWEST THURSDAY. AS A SHORTWAVE MOVES ACROSS THE GREAT
LAKES FRIDAY SOME OF THIS COLD AIR WILL ARRIVE LATE FRIDAY. UNLIKE
THE PAST SEVERAL ARCTIC INTRUSIONS...A SOUTHWESTERLY FLOW ALOFT WILL
LIMIT THE SOUTHWARD PENETRATION OF THE COLDEST OF THIS AIR. STILL
THOUGH...TEMPERATURES SHOULD SIGNIFICANTLY COOL THIS WEEKEND.
A LACK OF MOISTURE BE AN ISSUE THIS WEEKEND...SO EXPECT LITTLE MORE
THAN JUST A SLIGHT CHANCE OF LIGHT RAIN OR FLURRIES FRIDAY INTO
SATURDAY.
FORECAST MODELS STILL SUGGEST A POSSIBILITY OF MIXED PRECIPITATION
DEVELOPING MONDAY. OVERRUNNING PRECIPITATION WILL LIKELY DEVELOP
ACROSS THE LOWER OHIO VALLEY NORTH OF A FRONTAL BOUNDARY WHICH WILL
LIKELY SET UP ACROSS TENNESSEE. ARCTIC AIR WILL REMAIN CLOSE BY TO
OUR NORTH.
&&
.AVIATION (12Z TAFS)...
COOL NORTHWEST FLOW WILL PERSIST THROUGH THE TAF PERIOD WITH SOME
FLURRIES POSSIBLE EARLY ON. CEILINGS WILL PRIMARILY BE VFR...BUT IN
AND NEAR ANY LIGHT SNOW THEY WILL LIKELY FLUCTUATE ABOVE AND BELOW
THE 3K FT HEIGHT. THESE PERIODS OF MVFR CIGS WILL BE MOST LIKELY
DURING THE 12-18Z TUESDAY PERIOD AT SDF AND LEX. LIGHT SNOW WILL BE
MOST LIKELY AT LEX DURING 12-22Z...BUT CONFIDENCE IS LOW IN THESE
PASSING OVER THE TERMINAL LOCATION AND LEFT OUT OF THE TAFS AT THIS
TIME. CLOUDS SHOULD SCATTER OUT AND VFR CONDITIONS SHOULD PREVAIL
AFTER 00Z WEDNESDAY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
NEAR TERM....DK
SHORT TERM...MACZKO
LONG TERM....JSD
AVIATION.....MACZKO
000
FXUS63 KLMK 201123
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
623 AM EST TUE JAN 20 2009
.UPDATE...
UPDATE TO AVIATION DISCUSSION ONLY.
&&
.SHORT TERM (TODAY AND TONIGHT)...
COLD NORTHWEST FLOW TO PERSIST FOR ANOTHER DAY WITH A LITTLE WAVE
ENERGY AND WEAK WARM AIR ADVECTION ALOFT TO POTENTIALLY AID IN THE
DEVELOPMENT OF SOME FLURRIES ACROSS THE CWA THE FIRST HALF OF TODAY.
WITH LITTLE GOING ON NOW IN SIMILAR AIR MASS AND LITTLE ADDITIONAL
UPSTREAM MOISTURE TO WORK WITH...WOULD NOT EXPECT TOO MUCH IF ANY
FLURRIES TO OCCUR BUT CANNOT RULE THEM OUT ENTIRELY. BEST SHOT
THROUGH EARLY AFTERNOON WOULD BE IN THE NORTHEASTERN ZONES WHERE THE
BEST WARM AID ADVECTION IS PROGGED TO BE...SO WILL PUT SLIGHTLY
HIGHER POPS THERE...BUT NOT ENOUGH TO MENTION ANYTHING OTHER THAN
FLURRIES AT THIS TIME.
TEMPERATURES WILL STRUGGLE TODAY TO REACH THE UPPER 20S...ESPECIALLY
IN AREAS WITH A LITTLE MORE SNOW COVER. TONIGHT SKIES WILL BEGIN TO
CLEAR AND TEMPERATURES WILL FALL ONCE AGAIN INTO THE TEENS FOR MOST
LOCATIONS...THOUGH SOME ISOLATED LOWER 20S MAY OCCUR IN THE
SOUTHWEST.
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
WEDNESDAY THROUGH FRIDAY...
THE EXCEPTIONALLY AMPLIFIED WESTERN RIDGE/EASTERN TROUGH PATTERN
THAT HAS PERSISTED FOR A WEEK WILL FINALLY BREAK DOWN WEDNESDAY AS
PACIFIC ENERGY WILL ATTEMPT TO UNDERCUT THE BLOCKING 500MB RIDGE
ACROSS THE NORTHERN ROCKIES. A SPLIT FLOW PATTERN WILL DEVELOP
ACROSS THE WESTERN CONUS BY EARLY SATURDAY...AS THE SOUTHERN JET
FORMS ACROSS THE SOUTHWESTERN CONUS AND MEETS THE NORTHERN JET ON
THE EASTERN SIDE OF THIS SPLIT IN CONFLUENT FLOW ACROSS THE MIDWEST.
TRANQUIL WEATHER WITH PARTLY CLOUDY SKIES AND WARMING TEMPERATURES
ARE EXPECTED WEDNESDAY THROUGH FRIDAY. THE PERSISTENT TROUGH ACROSS
THE EASTERN CONUS WILL BEGIN TO EASE AND MOVE FARTHER EAST ACROSS
NEW ENGLAND. 500MB HEIGHTS WILL BEGIN TO RISE ACROSS THE LOWER OHIO
VALLEY BEGINNING WEDNESDAY.
AT THE SURFACE...THE AXIS OF A HIGH PRESSURE RIDGE WILL MOVE ACROSS
KENTUCKY EARLY WEDNESDAY. SOUTHWESTERLY FLOW WILL BEGIN WEDNESDAY
AND CONTINUE THROUGH FRIDAY AFTERNOON. AFTER A COLD START EARLY
WEDNESDAY...AFTERNOON TEMPERATURES WILL RISE 7 TO 10 DEGREES EACH
DAY THROUGH THURSDAY...MOST LIKELY REACHING THE MID TO UPPER 40S
THURSDAY AFTERNOON.
WITH NORTHWEST FLOW ALOFT AND SURFACE RIDGING ACROSS THE GULF
COAST...LITTLE MOISTURE WILL RETURN. EXPECT QUITE A BIT OF SUN MIXED
IN WITH SOME PASSING MID LEVEL CLOUDS THROUGH FRIDAY AFTERNOON.
SATURDAY THROUGH MONDAY...
A SHALLOW ARCTIC AIRMASS BUILDING IN CANADA WILL MOVE SOUTH INTO
THE UPPER MIDWEST THURSDAY. AS A SHORTWAVE MOVES ACROSS THE GREAT
LAKES FRIDAY SOME OF THIS COLD AIR WILL ARRIVE LATE FRIDAY. UNLIKE
THE PAST SEVERAL ARCTIC INTRUSIONS...A SOUTHWESTERLY FLOW ALOFT WILL
LIMIT THE SOUTHWARD PENETRATION OF THE COLDEST OF THIS AIR. STILL
THOUGH...TEMPERATURES SHOULD SIGNIFICANTLY COOL THIS WEEKEND.
A LACK OF MOISTURE BE AN ISSUE THIS WEEKEND...SO EXPECT LITTLE MORE
THAN JUST A SLIGHT CHANCE OF LIGHT RAIN OR FLURRIES FRIDAY INTO
SATURDAY.
FORECAST MODELS STILL SUGGEST A POSSIBILITY OF MIXED PRECIPITATION
DEVELOPING MONDAY. OVERRUNNING PRECIPITATION WILL LIKELY DEVELOP
ACROSS THE LOWER OHIO VALLEY NORTH OF A FRONTAL BOUNDARY WHICH WILL
LIKELY SET UP ACROSS TENNESSEE. ARCTIC AIR WILL REMAIN CLOSE BY TO
OUR NORTH.
&&
.AVIATION (12Z TAFS)...
COOL NORTHWEST FLOW WILL PERSIST THROUGH THE TAF PERIOD WITH SOME
FLURRIES POSSIBLE EARLY ON. CEILINGS WILL PRIMARILY BE VFR...BUT IN AND
NEAR ANY LIGHT SNOW THEY WILL LIKELY FLUCTUATE ABOVE AND BELOW THE
3K FT HEIGHT. THESE PERIODS OF MVFR CIGS WILL BE MOST LIKELY DURING
THE 12-18Z TUESDAY PERIOD AT SDF AND LEX. LIGHT SNOW WILL BE MOST
LIKELY AT LEX DURING 12-22Z...BUT CONFIDENCE IS LOW IN THESE PASSING
OVER THE TERMINAL LOCATION AND LEFT OUT OF THE TAFS AT THIS TIME.
CLOUDS SHOULD SCATTER OUT AND VFR CONDITIONS SHOULD PREVAIL AFTER
00Z WEDNESDAY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...MACZKO
LONG TERM....JSD
AVIATION.....MACZKO
000
FXUS63 KLMK 200750
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
250 AM EST TUE JAN 20 2009
.SHORT TERM (TODAY AND TONIGHT)...
COLD NORTHWEST FLOW TO PERSIST FOR ANOTHER DAY WITH A LITTLE WAVE
ENERGY AND WEAK WARM AIR ADVECTION ALOFT TO POTENTIALLY AID IN THE
DEVELOPMENT OF SOME FLURRIES ACROSS THE CWA THE FIRST HALF OF TODAY.
WITH LITTLE GOING ON NOW IN SIMILAR AIR MASS AND LITTLE ADDITIONAL
UPSTREAM MOISTURE TO WORK WITH...WOULD NOT EXPECT TOO MUCH IF ANY
FLURRIES TO OCCUR BUT CANNOT RULE THEM OUT ENTIRELY. BEST SHOT
THROUGH EARLY AFTERNOON WOULD BE IN THE NORTHEASTERN ZONES WHERE THE
BEST WARM AID ADVECTION IS PROGGED TO BE...SO WILL PUT SLIGHTLY
HIGHER POPS THERE...BUT NOT ENOUGH TO MENTION ANYTHING OTHER THAN
FLURRIES AT THIS TIME.
TEMPERATURES WILL STRUGGLE TODAY TO REACH THE UPPER 20S...ESPECIALLY
IN AREAS WITH A LITTLE MORE SNOW COVER. TONIGHT SKIES WILL BEGIN TO
CLEAR AND TEMPERATURES WILL FALL ONCE AGAIN INTO THE TEENS FOR MOST
LOCATIONS...THOUGH SOME ISOLATED LOWER 20S MAY OCCUR IN THE
SOUTHWEST.
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
WEDNESDAY THROUGH FRIDAY...
THE EXCEPTIONALLY AMPLIFIED WESTERN RIDGE/EASTERN TROUGH PATTERN
THAT HAS PERSISTED FOR A WEEK WILL FINALLY BREAK DOWN WEDNESDAY AS
PACIFIC ENERGY WILL ATTEMPT TO UNDERCUT THE BLOCKING 500MB RIDGE
ACROSS THE NORTHERN ROCKIES. A SPLIT FLOW PATTERN WILL DEVELOP
ACROSS THE WESTERN CONUS BY EARLY SATURDAY...AS THE SOUTHERN JET
FORMS ACROSS THE SOUTHWESTERN CONUS AND MEETS THE NORTHERN JET ON
THE EASTERN SIDE OF THIS SPLIT IN CONFLUENT FLOW ACROSS THE MIDWEST.
TRANQUIL WEATHER WITH PARTLY CLOUDY SKIES AND WARMING TEMPERATURES
ARE EXPECTED WEDNESDAY THROUGH FRIDAY. THE PERSISTENT TROUGH ACROSS
THE EASTERN CONUS WILL BEGIN TO EASE AND MOVE FARTHER EAST ACROSS
NEW ENGLAND. 500MB HEIGHTS WILL BEGIN TO RISE ACROSS THE LOWER OHIO
VALLEY BEGINNING WEDNESDAY.
AT THE SURFACE...THE AXIS OF A HIGH PRESSURE RIDGE WILL MOVE ACROSS
KENTUCKY EARLY WEDNESDAY. SOUTHWESTERLY FLOW WILL BEGIN WEDNESDAY
AND CONTINUE THROUGH FRIDAY AFTERNOON. AFTER A COLD START EARLY
WEDNESDAY...AFTERNOON TEMPERATURES WILL RISE 7 TO 10 DEGREES EACH
DAY THROUGH THURSDAY...MOST LIKELY REACHING THE MID TO UPPER 40S
THURSDAY AFTERNOON.
WITH NORTHWEST FLOW ALOFT AND SURFACE RIDGING ACROSS THE GULF
COAST...LITTLE MOISTURE WILL RETURN. EXPECT QUITE A BIT OF SUN MIXED
IN WITH SOME PASSING MID LEVEL CLOUDS THROUGH FRIDAY AFTERNOON.
SATURDAY THROUGH MONDAY...
A SHALLOW ARCTIC AIRMASS BUILDING IN CANADA WILL MOVE SOUTH INTO
THE UPPER MIDWEST THURSDAY. AS A SHORTWAVE MOVES ACROSS THE GREAT
LAKES FRIDAY SOME OF THIS COLD AIR WILL ARRIVE LATE FRIDAY. UNLIKE
THE PAST SEVERAL ARCTIC INTRUSIONS...A SOUTHWESTERLY FLOW ALOFT WILL
LIMIT THE SOUTHWARD PENETRATION OF THE COLDEST OF THIS AIR. STILL
THOUGH...TEMPERATURES SHOULD SIGNIFICANTLY COOL THIS WEEKEND.
A LACK OF MOISTURE BE AN ISSUE THIS WEEKEND...SO EXPECT LITTLE MORE
THAN JUST A SLIGHT CHANCE OF LIGHT RAIN OR FLURRIES FRIDAY INTO
SATURDAY.
FORECAST MODELS STILL SUGGEST A POSSIBILITY OF MIXED PRECIPITATION
DEVELOPING MONDAY. OVERRUNNING PRECIPITATION WILL LIKELY DEVELOP
ACROSS THE LOWER OHIO VALLEY NORTH OF A FRONTAL BOUNDARY WHICH WILL
LIKELY SET UP ACROSS TENNESSEE. ARCTIC AIR WILL REMAIN CLOSE BY TO
OUR NORTH.
&&
.AVIATION (06Z TAFS)...
COOL NORTHWEST FLOW WILL PERSIST THROUGH THE TAF PERIOD WITH SOME
FLURRIES POSSIBLE EARLY ON. CEILINGS WILL PRIMARILY BE VFR...BUT IN AND
NEAR ANY LIGHT SNOW THEY WILL LIKELY FLUCTUATE ABOVE AND BELOW THE
3K FT HEIGHT. THESE PERIODS OF MVFR IN/NEAR LIGHT SNOW WILL BE MOST
LIKELY DURING THE 06Z-14Z TUESDAY PERIOD...WITH VFR CONDITIONS AND
NO PRECIPITATION EXPECTED FOR THE REMAINDER OF THE TAF PERIOD AFTER
14Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...MACZKO
LONG TERM....JSD
AVIATION.....MACZKO
000
FXUS63 KLMK 200458
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1158 PM EST MON JAN 19 2009
.SHORT TERM (TONIGHT AND TUESDAY)...
DEEP UPPER TROUGH IS FCST TO MOVE SLOWLY EASTWARD OVER THE NEXT 24
HOURS. BEFORE THIS HAPPENS...ONE LAST VORTICITY MAXIMUM IS FCST TO
SLIDE DOWN THE WEST SIDE OF THE TROUGH AND INTO THE BASE LATER
TONIGHT. OVERALL TILT TO THE UPPER TROUGH HAS BECOME ALMOST
U-SHAPED OR NEUTRAL TILT. BECAUSE OF THIS TILT...THE VORT CURRENTLY
OVER WISCONSIN SHOULD SLIDE DIRECTLY TO THE SOUTH AND PASS JUST WEST
OF THE REGION TONIGHT. ASSOCIATED PVA IS MUCH MORE SHEARED WITH
THIS SYSTEM THAN LAST NIGHTS...SO PRECIPITATION ASSOCIATED WITH THIS
FEATURE DOES NOT LOOK ALL THAT ORGANIZED. WITH THE SYSTEM FORECAST
TO PASS TO OUR WEST...THERE IS A SLIGHT REFLECTION IN THE SHORT TERM
MODELS OF A SFC PRESSURE TROUGH THAT WILL SLIDE INTO THE REGION.
THIS FEATURE MAY PROVIDE ENOUGH LIFT FOR SOME SCATTERED SNOW
FLURRIES/SHOWERS ACROSS THE REGION. BASED ON THE LATEST SHORT TERM
GUIDANCE...THE BEST CHANCES FOR PRECIPITATION TONIGHT LOOK TO BE
WEST OF I-65. WITH THAT SAID...WILL CONTINUE CHANCE POPS ACROSS THE
WEST AND LOW CHANCE POPS ACROSS THE FAR EAST. TEMPERATURES ARE
FORECAST TO DROP INTO THE LOW TO MID TEENS...SO SNOW RATIOS WOULD BE
RATHER HIGH OVERNIGHT...SUCH THAT A QUARTER TO A THIRD OF AN INCH IS
POSSIBLE IN AREAS WEST OF I-65. IN ADDITION...SIGNIFICANT MELTING
HAS OCCURRED ACROSS THE REGION. THE COMBINATION OF WET ROADWAYS AND
TEMPS DROPPING WELL BELOW FREEZING WILL SET THE STAGE FOR A
RE-FREEZE TONIGHT. THE MAIN/HEAVILY TRAVELED ROADS SHOULD BE OK
DUE TO THEM DRYING OUT WITH THE HIGHER TRAFFIC VOLUME.
HOWEVER...SECONDARY LESS TRAVELED ROADS AND NEIGHBORHOOD STREETS
COULD BE QUITE ICY IN THE MORNING. WILL BE HIGHLIGHT THIS RISK IN
THE HAZARDOUS WEATHER OUTLOOK THIS AFTERNOON.
FOR TUESDAY...THE DAY WILL LIKELY START OFF MOSTLY CLOUDY WITH
SCATTERED SNOW SHOWERS/FLURRIES DOTTING THE LANDSCAPE. AS VORT MAX
MOVES TO OUR SOUTH AND SOUTHEAST...NORTHWEST FLOW SHOULD PROMOTE
SCATTERED SNOW SHOWERS AND FLURRIES ACROSS THE REGION. FEEL THAT
BEST CHANCES OF FLURRIES WILL BE ACROSS OUR TOPOGRAPHICALLY FAVORED
BLUEGRASS REGION. GENERALLY WENT CLOSE TO A BLEND OF THE NAM AND GFS
RAW GUIDANCE FOR HIGHS. AFTERNOON HIGHS IN THE LOWER 20S IN THE
NORTHEAST/BLUEGRASS TO THE MID AND UPPER 20S IN THE SOUTHWEST ARE
EXPECTED.
.LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...
TUE NIGHT THRU THU NIGHT...
DRY THRUOUT AND AFTER A COLD TUE NIGHT...A WARMING TREND THRU THE
PERIOD.
WE START ON THE BACKSIDE OF A DEEP TROF TUE NIGHT AND TRANSITION TO
ZONAL FLO BY LATE THU AS FLO BACKS FROM NLY TO WLY. A RIDGE OF HI
PRES EXTENDING FROM SRN TEXAS INTO THE MID MS VLY WILL MOVE ACRS OUR
FA TUE NIGHT RESULTING IN ANOTHER NIGHT WITH MINIMUM TEMPS MOSTLY IN
THE TEENS. A WARMING TREND BEGINS WED AS WINDS BECOME SW IN ADVANCE
OF A WEAK TROF OF LOW PRES THAT WASHES OUT BEFORE REACHING OUR AREA.
WARMING WILL CONTINUE INTO THU IN SW FLO WITH HIGH PRES POSITIONED
ACRS THE GULF AND LOW PRES EVOLVING OVER THE SRN PLAINS.
MAX TEMPS SHUD BE ABOUT 10 DEGS WARMER ON SUCCEEDING DAYS STARTING
WED WITH MAXS REACHING THE MID TO UPPER 40S ON THU.
FRI THRU MON...
WILL MAINLY FOLLOW THE MORE CONSISTENT EURO/EURO ENSEMBLES...FAVORED
BY HPC WITH THE 12Z GFS RUN CLOSER TO THE 00Z EURO.
WE TRANSITION FROM A WNW UPPER LEVEL FLOW PATTERN THRU MUCH OF THE
PERIOD TO WSW BY MON...WHEN IT APPEARS THE MOST SIGNIFICANT CHC FOR
PCPN WILL OCCUR. WILL KEEP LOW CHC POPS IN FOR FRI (RAIN) WITH A
COLD FROPA AND THEN CHANGE PRECIP TYPE TO SNOW FOR FRI NIGHT AS A
WAVE DEVELOPS ON THE FRONT AS IT REACHES THE TN VALLEY. WILL ADD A
CHC FOR SNOW SHOWERS SAT IN THE POST COLD FRONTAL AMS AS AN UPPER
TROF DROPS SEWD INTO THE OH VLY.
HI PRES DROPPING ESE FROM THE MID/UPR MS VLY SHUD PROVIDE DRY...
ALBEIT COLD WX FOR SAT NIGHT AND SUN AS THE HIGH MOVES ACRS THE OH
VLY TO THE MID ATLANTIC STATES BY SUN EVE. AFOREMENTIONED UPR LEVEL
FLO BACKS TO WSW MON AS A BROAD TROF EVOLVES OVER THE NATIONS
MID-SECTION BY MON NIGHT. WARM/MOIST ADVECTION/OVERRUNNING BEGINS
SUN NIGHT RESULTING IN A CHC OF RAIN OR SNOW LATE. ALL PRECIP SHUD
TRANSITION TO LIQUID MON WITH THE BEST CHC OF PRECIP AT THIS TIME AS
UPR TROF DEVELOPS UPSTREAM AND A WARM FRONT MOVES THRU. FORCING FOR
ASCENT CONTS MON NIGHT AS A CDFNT MOVES INTO OUR FA. A CHECK OF TIME
HEIGHT CROSS SECTIONS FROM THE 00Z EURO/12Z GFS REVEAL THAT PRECIP
WILL LIKELY START AS SNOW LATE SUN NIGHT OR EARLY MON...THEN CHANGE
TO RAIN BY MON AFTN. FROM A PATTERN RECOGNITION STANDPOINT...MOST
LIKELY SCENARIO IS PRE-WARM FRONT SNOW WITH A TRANSITION TO LIQUID
AFTER FRONTAL PASSAGE. AT THIS POINT...WILL NOT GET TOO DETAILED IN
THE FCST.
GENERALLY FAVORED THE COLDER TEMPS FROM THE EURO/HPC THRU THE
PERIOD...THIS IN LINE WITH THE NEW 12Z GFS.
&&
.AVIATION (06Z TAFS)...
COOL NORTHWEST FLOW WILL PERSIST THROUGH THE TAF PERIOD WITH SOME
FLURRIES POSSIBLE EARLY ON. CEILINGS WILL PRIMARILY BE VFR...BUT IN AND
NEAR ANY LIGHT SNOW THEY WILL LIKELY FLUCTUATE ABOVE AND BELOW THE
3K FT HEIGHT. THESE PERIODS OF MVFR IN/NEAR LIGHT SNOW WILL BE MOST
LIKELY DURING THE 06Z-14Z TUESDAY PERIOD...WITH VFR CONDITIONS AND
NO PRECIPITATION EXPECTED FOR THE REMAINDER OF THE TAF PERIOD AFTER
14Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...MJ
LONG TERM....DK
AVIATION.....MACZKO
000
FXUS63 KLMK 200234
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
935 PM EST MON JAN 19 2009
.EVENING UPDATE...
CURRENT FORECAST IS ON TRACK AND I WILL MAKE ONLY MINOR ADJUSTMENTS
TO OVERNIGHT TEMPERATURES BY LOWERING THEM A FEW DEGREES. THIS IS
BASED ON UPSTREAM READINGS AT THE PRESENT TIME. WILL CONTINUE TO
HOLD ONTO CHANCE POPS FOR SNOW AS CURRENT OBSERVATIONS ACROSS
CENTRAL AND NORTHERN ILLINOIS INDICATE SOME LIGHT SNOW ASSOCIATED
WITH THE VORT MAX DROPPING INTO THE BASE OF THE UPPER TROUGH
TONIGHT.
SHORT TERM (TONIGHT AND TUESDAY)...
DEEP UPPER TROUGH IS FCST TO MOVE SLOWLY EASTWARD OVER THE NEXT 24
HOURS. BEFORE THIS HAPPENS...ONE LAST VORTICITY MAXIMUM IS FCST TO
SLIDE DOWN THE WEST SIDE OF THE TROUGH AND INTO THE BASE LATER
TONIGHT. OVERALL TILT TO THE UPPER TROUGH HAS BECOME ALMOST
U-SHAPED OR NEUTRAL TILT. BECAUSE OF THIS TILT...THE VORT CURRENTLY
OVER WISCONSIN SHOULD SLIDE DIRECTLY TO THE SOUTH AND PASS JUST WEST
OF THE REGION TONIGHT. ASSOCIATED PVA IS MUCH MORE SHEARED WITH
THIS SYSTEM THAN LAST NIGHTS...SO PRECIPITATION ASSOCIATED WITH THIS
FEATURE DOES NOT LOOK ALL THAT ORGANIZED. WITH THE SYSTEM FORECAST
TO PASS TO OUR WEST...THERE IS A SLIGHT REFLECTION IN THE SHORT TERM
MODELS OF A SFC PRESSURE TROUGH THAT WILL SLIDE INTO THE REGION.
THIS FEATURE MAY PROVIDE ENOUGH LIFT FOR SOME SCATTERED SNOW
FLURRIES/SHOWERS ACROSS THE REGION. BASED ON THE LATEST SHORT TERM
GUIDANCE...THE BEST CHANCES FOR PRECIPITATION TONIGHT LOOK TO BE
WEST OF I-65. WITH THAT SAID...WILL CONTINUE CHANCE POPS ACROSS THE
WEST AND LOW CHANCE POPS ACROSS THE FAR EAST. TEMPERATURES ARE
FORECAST TO DROP INTO THE LOW TO MID TEENS...SO SNOW RATIOS WOULD BE
RATHER HIGH OVERNIGHT...SUCH THAT A QUARTER TO A THIRD OF AN INCH IS
POSSIBLE IN AREAS WEST OF I-65. IN ADDITION...SIGNIFICANT MELTING
HAS OCCURRED ACROSS THE REGION. THE COMBINATION OF WET ROADWAYS AND
TEMPS DROPPING WELL BELOW FREEZING WILL SET THE STAGE FOR A
RE-FREEZE TONIGHT. THE MAIN/HEAVILY TRAVELED ROADS SHOULD BE OK
DUE TO THEM DRYING OUT WITH THE HIGHER TRAFFIC VOLUME.
HOWEVER...SECONDARY LESS TRAVELED ROADS AND NEIGHBORHOOD STREETS
COULD BE QUITE ICY IN THE MORNING. WILL BE HIGHLIGHT THIS RISK IN
THE HAZARDOUS WEATHER OUTLOOK THIS AFTERNOON.
FOR TUESDAY...THE DAY WILL LIKELY START OFF MOSTLY CLOUDY WITH
SCATTERED SNOW SHOWERS/FLURRIES DOTTING THE LANDSCAPE. AS VORT MAX
MOVES TO OUR SOUTH AND SOUTHEAST...NORTHWEST FLOW SHOULD PROMOTE
SCATTERED SNOW SHOWERS AND FLURRIES ACROSS THE REGION. FEEL THAT
BEST CHANCES OF FLURRIES WILL BE ACROSS OUR TOPOGRAPHICALLY FAVORED
BLUEGRASS REGION. GENERALLY WENT CLOSE TO A BLEND OF THE NAM AND GFS
RAW GUIDANCE FOR HIGHS. AFTERNOON HIGHS IN THE LOWER 20S IN THE
NORTHEAST/BLUEGRASS TO THE MID AND UPPER 20S IN THE SOUTHWEST ARE
EXPECTED.
.LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...
TUE NIGHT THRU THU NIGHT...
DRY THRUOUT AND AFTER A COLD TUE NIGHT...A WARMING TREND THRU THE
PERIOD.
WE START ON THE BACKSIDE OF A DEEP TROF TUE NIGHT AND TRANSITION TO
ZONAL FLO BY LATE THU AS FLO BACKS FROM NLY TO WLY. A RIDGE OF HI
PRES EXTENDING FROM SRN TEXAS INTO THE MID MS VLY WILL MOVE ACRS OUR
FA TUE NIGHT RESULTING IN ANOTHER NIGHT WITH MINIMUM TEMPS MOSTLY IN
THE TEENS. A WARMING TREND BEGINS WED AS WINDS BECOME SW IN ADVANCE
OF A WEAK TROF OF LOW PRES THAT WASHES OUT BEFORE REACHING OUR AREA.
WARMING WILL CONTINUE INTO THU IN SW FLO WITH HIGH PRES POSITIONED
ACRS THE GULF AND LOW PRES EVOLVING OVER THE SRN PLAINS.
MAX TEMPS SHUD BE ABOUT 10 DEGS WARMER ON SUCCEEDING DAYS STARTING
WED WITH MAXS REACHING THE MID TO UPPER 40S ON THU.
FRI THRU MON...
WILL MAINLY FOLLOW THE MORE CONSISTENT EURO/EURO ENSEMBLES...FAVORED
BY HPC WITH THE 12Z GFS RUN CLOSER TO THE 00Z EURO.
WE TRANSITION FROM A WNW UPPER LEVEL FLOW PATTERN THRU MUCH OF THE
PERIOD TO WSW BY MON...WHEN IT APPEARS THE MOST SIGNIFICANT CHC FOR
PCPN WILL OCCUR. WILL KEEP LOW CHC POPS IN FOR FRI (RAIN) WITH A
COLD FROPA AND THEN CHANGE PRECIP TYPE TO SNOW FOR FRI NIGHT AS A
WAVE DEVELOPS ON THE FRONT AS IT REACHES THE TN VALLEY. WILL ADD A
CHC FOR SNOW SHOWERS SAT IN THE POST COLD FRONTAL AMS AS AN UPPER
TROF DROPS SEWD INTO THE OH VLY.
HI PRES DROPPING ESE FROM THE MID/UPR MS VLY SHUD PROVIDE DRY...
ALBEIT COLD WX FOR SAT NIGHT AND SUN AS THE HIGH MOVES ACRS THE OH
VLY TO THE MID ATLANTIC STATES BY SUN EVE. AFOREMENTIONED UPR LEVEL
FLO BACKS TO WSW MON AS A BROAD TROF EVOLVES OVER THE NATIONS
MID-SECTION BY MON NIGHT. WARM/MOIST ADVECTION/OVERRUNNING BEGINS
SUN NIGHT RESULTING IN A CHC OF RAIN OR SNOW LATE. ALL PRECIP SHUD
TRANSITION TO LIQUID MON WITH THE BEST CHC OF PRECIP AT THIS TIME AS
UPR TROF DEVELOPS UPSTREAM AND A WARM FRONT MOVES THRU. FORCING FOR
ASCENT CONTS MON NIGHT AS A CDFNT MOVES INTO OUR FA. A CHECK OF TIME
HEIGHT CROSS SECTIONS FROM THE 00Z EURO/12Z GFS REVEAL THAT PRECIP
WILL LIKELY START AS SNOW LATE SUN NIGHT OR EARLY MON...THEN CHANGE
TO RAIN BY MON AFTN. FROM A PATTERN RECOGNITION STANDPOINT...MOST
LIKELY SCENARIO IS PRE-WARM FRONT SNOW WITH A TRANSITION TO LIQUID
AFTER FRONTAL PASSAGE. AT THIS POINT...WILL NOT GET TOO DETAILED IN
THE FCST.
GENERALLY FAVORED THE COLDER TEMPS FROM THE EURO/HPC THRU THE
PERIOD...THIS IN LINE WITH THE NEW 12Z GFS.
&&
.AVIATION (18Z TAFS)...
A COLD NORTHERLY FLOW WILL CONTINUE ACROSS CENTRAL KENTUCKY FOR THIS
FORECAST PERIOD. A WEAK CLIPPER TYPE SYSTEM LOCATED OVER IOWA AND
MISSOURI AT 23Z WILL DROP INTO WESTERN KENTUCKY AND TENNESSEE
OVERNIGHT. SOME LIGHT SNOW OR FLURRIES WILL BE POSSIBLE BUT MOST
PRECIPITATION WILL REMAIN WEST OF THE BWG AND SDF TAF SITES. SO
MAINLY VFR CONDITIONS EXPECTED EXCEPT FOR POSSIBLY SOME MVFR CIGS
AND VSBYS IN LIGHT SNOW BETWEEN 06-12Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....DK
AVIATION.....JA
000
FXUS63 KLMK 192321 CCA
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
617 PM EST MON JAN 19 2009
.UPDATE FOR 00Z TAF`S
SHORT TERM (TONIGHT AND TUESDAY)...
DEEP UPPER TROUGH IS FCST TO MOVE SLOWLY EASTWARD OVER THE NEXT 24
HOURS. BEFORE THIS HAPPENS...ONE LAST VORTICITY MAXIMUM IS FCST TO
SLIDE DOWN THE WEST SIDE OF THE TROUGH AND INTO THE BASE LATER
TONIGHT. OVERALL TILT TO THE UPPER TROUGH HAS BECOME ALMOST
U-SHAPED OR NEUTRAL TILT. BECAUSE OF THIS TILT...THE VORT CURRENTLY
OVER WISCONSIN SHOULD SLIDE DIRECTLY TO THE SOUTH AND PASS JUST WEST
OF THE REGION TONIGHT. ASSOCIATED PVA IS MUCH MORE SHEARED WITH
THIS SYSTEM THAN LAST NIGHTS...SO PRECIPITATION ASSOCIATED WITH THIS
FEATURE DOES NOT LOOK ALL THAT ORGANIZED. WITH THE SYSTEM FORECAST
TO PASS TO OUR WEST...THERE IS A SLIGHT REFLECTION IN THE SHORT TERM
MODELS OF A SFC PRESSURE TROUGH THAT WILL SLIDE INTO THE REGION.
THIS FEATURE MAY PROVIDE ENOUGH LIFT FOR SOME SCATTERED SNOW
FLURRIES/SHOWERS ACROSS THE REGION. BASED ON THE LATEST SHORT TERM
GUIDANCE...THE BEST CHANCES FOR PRECIPITATION TONIGHT LOOK TO BE
WEST OF I-65. WITH THAT SAID...WILL CONTINUE CHANCE POPS ACROSS THE
WEST AND LOW CHANCE POPS ACROSS THE FAR EAST. TEMPERATURES ARE
FORECAST TO DROP INTO THE LOW TO MID TEENS...SO SNOW RATIOS WOULD BE
RATHER HIGH OVERNIGHT...SUCH THAT A QUARTER TO A THIRD OF AN INCH IS
POSSIBLE IN AREAS WEST OF I-65. IN ADDITION...SIGNIFICANT MELTING
HAS OCCURRED ACROSS THE REGION. THE COMBINATION OF WET ROADWAYS AND
TEMPS DROPPING WELL BELOW FREEZING WILL SET THE STAGE FOR A
RE-FREEZE TONIGHT. THE MAIN/HEAVILY TRAVELED ROADS SHOULD BE OK
DUE TO THEM DRYING OUT WITH THE HIGHER TRAFFIC VOLUME.
HOWEVER...SECONDARY LESS TRAVELED ROADS AND NEIGHBORHOOD STREETS
COULD BE QUITE ICY IN THE MORNING. WILL BE HIGHLIGHT THIS RISK IN
THE HAZARDOUS WEATHER OUTLOOK THIS AFTERNOON.
FOR TUESDAY...THE DAY WILL LIKELY START OFF MOSTLY CLOUDY WITH
SCATTERED SNOW SHOWERS/FLURRIES DOTTING THE LANDSCAPE. AS VORT MAX
MOVES TO OUR SOUTH AND SOUTHEAST...NORTHWEST FLOW SHOULD PROMOTE
SCATTERED SNOW SHOWERS AND FLURRIES ACROSS THE REGION. FEEL THAT
BEST CHANCES OF FLURRIES WILL BE ACROSS OUR TOPOGRAPHICALLY FAVORED
BLUEGRASS REGION. GENERALLY WENT CLOSE TO A BLEND OF THE NAM AND GFS
RAW GUIDANCE FOR HIGHS. AFTERNOON HIGHS IN THE LOWER 20S IN THE
NORTHEAST/BLUEGRASS TO THE MID AND UPPER 20S IN THE SOUTHWEST ARE
EXPECTED.
.LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...
TUE NIGHT THRU THU NIGHT...
DRY THRUOUT AND AFTER A COLD TUE NIGHT...A WARMING TREND THRU THE
PERIOD.
WE START ON THE BACKSIDE OF A DEEP TROF TUE NIGHT AND TRANSITION TO
ZONAL FLO BY LATE THU AS FLO BACKS FROM NLY TO WLY. A RIDGE OF HI
PRES EXTENDING FROM SRN TEXAS INTO THE MID MS VLY WILL MOVE ACRS OUR
FA TUE NIGHT RESULTING IN ANOTHER NIGHT WITH MINIMUM TEMPS MOSTLY IN
THE TEENS. A WARMING TREND BEGINS WED AS WINDS BECOME SW IN ADVANCE
OF A WEAK TROF OF LOW PRES THAT WASHES OUT BEFORE REACHING OUR AREA.
WARMING WILL CONTINUE INTO THU IN SW FLO WITH HIGH PRES POSITIONED
ACRS THE GULF AND LOW PRES EVOLVING OVER THE SRN PLAINS.
MAX TEMPS SHUD BE ABOUT 10 DEGS WARMER ON SUCCEEDING DAYS STARTING
WED WITH MAXS REACHING THE MID TO UPPER 40S ON THU.
FRI THRU MON...
WILL MAINLY FOLLOW THE MORE CONSISTENT EURO/EURO ENSEMBLES...FAVORED
BY HPC WITH THE 12Z GFS RUN CLOSER TO THE 00Z EURO.
WE TRANSITION FROM A WNW UPPER LEVEL FLOW PATTERN THRU MUCH OF THE
PERIOD TO WSW BY MON...WHEN IT APPEARS THE MOST SIGNIFICANT CHC FOR
PCPN WILL OCCUR. WILL KEEP LOW CHC POPS IN FOR FRI (RAIN) WITH A
COLD FROPA AND THEN CHANGE PRECIP TYPE TO SNOW FOR FRI NIGHT AS A
WAVE DEVELOPS ON THE FRONT AS IT REACHES THE TN VALLEY. WILL ADD A
CHC FOR SNOW SHOWERS SAT IN THE POST COLD FRONTAL AMS AS AN UPPER
TROF DROPS SEWD INTO THE OH VLY.
HI PRES DROPPING ESE FROM THE MID/UPR MS VLY SHUD PROVIDE DRY...
ALBEIT COLD WX FOR SAT NIGHT AND SUN AS THE HIGH MOVES ACRS THE OH
VLY TO THE MID ATLANTIC STATES BY SUN EVE. AFOREMENTIONED UPR LEVEL
FLO BACKS TO WSW MON AS A BROAD TROF EVOLVES OVER THE NATIONS
MID-SECTION BY MON NIGHT. WARM/MOIST ADVECTION/OVERRUNNING BEGINS
SUN NIGHT RESULTING IN A CHC OF RAIN OR SNOW LATE. ALL PRECIP SHUD
TRANSITION TO LIQUID MON WITH THE BEST CHC OF PRECIP AT THIS TIME AS
UPR TROF DEVELOPS UPSTREAM AND A WARM FRONT MOVES THRU. FORCING FOR
ASCENT CONTS MON NIGHT AS A CDFNT MOVES INTO OUR FA. A CHECK OF TIME
HEIGHT CROSS SECTIONS FROM THE 00Z EURO/12Z GFS REVEAL THAT PRECIP
WILL LIKELY START AS SNOW LATE SUN NIGHT OR EARLY MON...THEN CHANGE
TO RAIN BY MON AFTN. FROM A PATTERN RECOGNITION STANDPOINT...MOST
LIKELY SCENARIO IS PRE-WARM FRONT SNOW WITH A TRANSITION TO LIQUID
AFTER FRONTAL PASSAGE. AT THIS POINT...WILL NOT GET TOO DETAILED IN
THE FCST.
GENERALLY FAVORED THE COLDER TEMPS FROM THE EURO/HPC THRU THE
PERIOD...THIS IN LINE WITH THE NEW 12Z GFS.
&&
.AVIATION (18Z TAFS)...
A COLD NORTHERLY FLOW WILL CONTINUE ACROSS CENTRAL KENTUCKY FOR THIS
FORECAST PERIOD. A WEAK CLIPPER TYPE SYSTEM LOCATED OVER IOWA AND
MISSOURI AT 23Z WILL DROP INTO WESTERN KENTUCKY AND TENNESSEE
OVERNIGHT. SOME LIGHT SNOW OR FLURRIES WILL BE POSSIBLE BUT MOST
PRECIPITATION WILL REMAIN WEST OF THE BWG AND SDF TAF SITES. SO
MAINLY VFR CONDITIONS EXPECTED EXCEPT FOR POSSIBLY SOME MVFR CIGS
AND VSBYS IN LIGHT SNOW BETWEEN 06-12Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....DK
AVIATION.....JA
000
FXUS63 KLMK 192316
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
617 PM EST MON JAN 19 2009
.UPDATE FOR 00Z TAF`S
SHORT TERM (TONIGHT AND TUESDAY)...
DEEP UPPER TROUGH IS FCST TO MOVE SLOWLY EASTWARD OVER THE NEXT 24
HOURS. BEFORE THIS HAPPENS...ONE LAST VORTICITY MAXIMUM IS FCST TO
SLIDE DOWN THE WEST SIDE OF THE TROUGH AND INTO THE BASE LATER
TONIGHT. OVERALL TILT TO THE UPPER TROUGH HAS BECOME ALMOST
U-SHAPED OR NEUTRAL TILT. BECAUSE OF THIS TILT...THE VORT CURRENTLY
OVER WISCONSIN SHOULD SLIDE DIRECTLY TO THE SOUTH AND PASS JUST WEST
OF THE REGION TONIGHT. ASSOCIATED PVA IS MUCH MORE SHEARED WITH
THIS SYSTEM THAN LAST NIGHTS...SO PRECIPITATION ASSOCIATED WITH THIS
FEATURE DOES NOT LOOK ALL THAT ORGANIZED. WITH THE SYSTEM FORECAST
TO PASS TO OUR WEST...THERE IS A SLIGHT REFLECTION IN THE SHORT TERM
MODELS OF A SFC PRESSURE TROUGH THAT WILL SLIDE INTO THE REGION.
THIS FEATURE MAY PROVIDE ENOUGH LIFT FOR SOME SCATTERED SNOW
FLURRIES/SHOWERS ACROSS THE REGION. BASED ON THE LATEST SHORT TERM
GUIDANCE...THE BEST CHANCES FOR PRECIPITATION TONIGHT LOOK TO BE
WEST OF I-65. WITH THAT SAID...WILL CONTINUE CHANCE POPS ACROSS THE
WEST AND LOW CHANCE POPS ACROSS THE FAR EAST. TEMPERATURES ARE
FORECAST TO DROP INTO THE LOW TO MID TEENS...SO SNOW RATIOS WOULD BE
RATHER HIGH OVERNIGHT...SUCH THAT A QUARTER TO A THIRD OF AN INCH IS
POSSIBLE IN AREAS WEST OF I-65. IN ADDITION...SIGNIFICANT MELTING
HAS OCCURRED ACROSS THE REGION. THE COMBINATION OF WET ROADWAYS AND
TEMPS DROPPING WELL BELOW FREEZING WILL SET THE STAGE FOR A
RE-FREEZE TONIGHT. THE MAIN/HEAVILY TRAVELED ROADS SHOULD BE OK
DUE TO THEM DRYING OUT WITH THE HIGHER TRAFFIC VOLUME.
HOWEVER...SECONDARY LESS TRAVELED ROADS AND NEIGHBORHOOD STREETS
COULD BE QUITE ICY IN THE MORNING. WILL BE HIGHLIGHT THIS RISK IN
THE HAZARDOUS WEATHER OUTLOOK THIS AFTERNOON.
FOR TUESDAY...THE DAY WILL LIKELY START OFF MOSTLY CLOUDY WITH
SCATTERED SNOW SHOWERS/FLURRIES DOTTING THE LANDSCAPE. AS VORT MAX
MOVES TO OUR SOUTH AND SOUTHEAST...NORTHWEST FLOW SHOULD PROMOTE
SCATTERED SNOW SHOWERS AND FLURRIES ACROSS THE REGION. FEEL THAT
BEST CHANCES OF FLURRIES WILL BE ACROSS OUR TOPOGRAPHICALLY FAVORED
BLUEGRASS REGION. GENERALLY WENT CLOSE TO A BLEND OF THE NAM AND GFS
RAW GUIDANCE FOR HIGHS. AFTERNOON HIGHS IN THE LOWER 20S IN THE
NORTHEAST/BLUEGRASS TO THE MID AND UPPER 20S IN THE SOUTHWEST ARE
EXPECTED.
.LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...
TUE NIGHT THRU THU NIGHT...
DRY THRUOUT AND AFTER A COLD TUE NIGHT...A WARMING TREND THRU THE
PERIOD.
WE START ON THE BACKSIDE OF A DEEP TROF TUE NIGHT AND TRANSITION TO
ZONAL FLO BY LATE THU AS FLO BACKS FROM NLY TO WLY. A RIDGE OF HI
PRES EXTENDING FROM SRN TEXAS INTO THE MID MS VLY WILL MOVE ACRS OUR
FA TUE NIGHT RESULTING IN ANOTHER NIGHT WITH MINIMUM TEMPS MOSTLY IN
THE TEENS. A WARMING TREND BEGINS WED AS WINDS BECOME SW IN ADVANCE
OF A WEAK TROF OF LOW PRES THAT WASHES OUT BEFORE REACHING OUR AREA.
WARMING WILL CONTINUE INTO THU IN SW FLO WITH HIGH PRES POSITIONED
ACRS THE GULF AND LOW PRES EVOLVING OVER THE SRN PLAINS.
MAX TEMPS SHUD BE ABOUT 10 DEGS WARMER ON SUCCEEDING DAYS STARTING
WED WITH MAXS REACHING THE MID TO UPPER 40S ON THU.
FRI THRU MON...
WILL MAINLY FOLLOW THE MORE CONSISTENT EURO/EURO ENSEMBLES...FAVORED
BY HPC WITH THE 12Z GFS RUN CLOSER TO THE 00Z EURO.
WE TRANSITION FROM A WNW UPPER LEVEL FLOW PATTERN THRU MUCH OF THE
PERIOD TO WSW BY MON...WHEN IT APPEARS THE MOST SIGNIFICANT CHC FOR
PCPN WILL OCCUR. WILL KEEP LOW CHC POPS IN FOR FRI (RAIN) WITH A
COLD FROPA AND THEN CHANGE PRECIP TYPE TO SNOW FOR FRI NIGHT AS A
WAVE DEVELOPS ON THE FRONT AS IT REACHES THE TN VALLEY. WILL ADD A
CHC FOR SNOW SHOWERS SAT IN THE POST COLD FRONTAL AMS AS AN UPPER
TROF DROPS SEWD INTO THE OH VLY.
HI PRES DROPPING ESE FROM THE MID/UPR MS VLY SHUD PROVIDE DRY...
ALBEIT COLD WX FOR SAT NIGHT AND SUN AS THE HIGH MOVES ACRS THE OH
VLY TO THE MID ATLANTIC STATES BY SUN EVE. AFOREMENTIONED UPR LEVEL
FLO BACKS TO WSW MON AS A BROAD TROF EVOLVES OVER THE NATIONS
MID-SECTION BY MON NIGHT. WARM/MOIST ADVECTION/OVERRUNNING BEGINS
SUN NIGHT RESULTING IN A CHC OF RAIN OR SNOW LATE. ALL PRECIP SHUD
TRANSITION TO LIQUID MON WITH THE BEST CHC OF PRECIP AT THIS TIME AS
UPR TROF DEVELOPS UPSTREAM AND A WARM FRONT MOVES THRU. FORCING FOR
ASCENT CONTS MON NIGHT AS A CDFNT MOVES INTO OUR FA. A CHECK OF TIME
HEIGHT CROSS SECTIONS FROM THE 00Z EURO/12Z GFS REVEAL THAT PRECIP
WILL LIKELY START AS SNOW LATE SUN NIGHT OR EARLY MON...THEN CHANGE
TO RAIN BY MON AFTN. FROM A PATTERN RECOGNITION STANDPOINT...MOST
LIKELY SCENARIO IS PRE-WARM FRONT SNOW WITH A TRANSITION TO LIQUID
AFTER FRONTAL PASSAGE. AT THIS POINT...WILL NOT GET TOO DETAILED IN
THE FCST.
GENERALLY FAVORED THE COLDER TEMPS FROM THE EURO/HPC THRU THE
PERIOD...THIS IN LINE WITH THE NEW 12Z GFS.
&&
.AVIATION (18Z TAFS)...
A COLD NORTHERLY FLOW WILL CONTINUE ACROSS CENTRAL KENTUCKY FOR THIS
FORECAST PERIOD. A WEAK CLIPPER TYPE SYSTEM LOCATED OVER IOWA AND
MISSOURI AT 23Z WILL DROP INTO WESTERN KENTUCKY AND TENNESSEE
OVERNIGHT. SOME LIGHT SNOW OR FLURRIES WILL BE POSSIBLE BUT MOST
PRECIPITATION WILL REMAIN WEST OF THE BWG AND SDF TAF SITES. SO
MAINLY VFR CONDITIONS EXPECTED EXCEPT FOR POSSIBLY SOME MVFR CIGS
AND VSBYS IN LIGHT SNOW BETWEEN 03-08Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....DK
AVIATION.....JA
000
FXUS63 KLMK 192001
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
301 PM EST MON JAN 19 2009
.SHORT TERM (TONIGHT AND TUESDAY)...
DEEP UPPER TROUGH IS FCST TO MOVE SLOWLY EASTWARD OVER THE NEXT 24
HOURS. BEFORE THIS HAPPENS...ONE LAST VORTICITY MAXIMUM IS FCST TO
SLIDE DOWN THE WEST SIDE OF THE TROUGH AND INTO THE BASE LATER
TONIGHT. OVERALL TILT TO THE UPPER TROUGH HAS BECOME ALMOST
U-SHAPED OR NEUTRAL TILT. BECAUSE OF THIS TILT...THE VORT CURRENTLY
OVER WISCONSIN SHOULD SLIDE DIRECTLY TO THE SOUTH AND PASS JUST WEST
OF THE REGION TONIGHT. ASSOCIATED PVA IS MUCH MORE SHEARED WITH
THIS SYSTEM THAN LAST NIGHTS...SO PRECIPITATION ASSOCIATED WITH THIS
FEATURE DOES NOT LOOK ALL THAT ORGANIZED. WITH THE SYSTEM FORECAST
TO PASS TO OUR WEST...THERE IS A SLIGHT REFLECTION IN THE SHORT TERM
MODELS OF A SFC PRESSURE TROUGH THAT WILL SLIDE INTO THE REGION.
THIS FEATURE MAY PROVIDE ENOUGH LIFT FOR SOME SCATTERED SNOW
FLURRIES/SHOWERS ACROSS THE REGION. BASED ON THE LATEST SHORT TERM
GUIDANCE...THE BEST CHANCES FOR PRECIPITATION TONIGHT LOOK TO BE
WEST OF I-65. WITH THAT SAID...WILL CONTINUE CHANCE POPS ACROSS THE
WEST AND LOW CHANCE POPS ACROSS THE FAR EAST. TEMPERATURES ARE
FORECAST TO DROP INTO THE LOW TO MID TEENS...SO SNOW RATIOS WOULD BE
RATHER HIGH OVERNIGHT...SUCH THAT A QUARTER TO A THIRD OF AN INCH IS
POSSIBLE IN AREAS WEST OF I-65. IN ADDITION...SIGNIFICANT MELTING
HAS OCCURRED ACROSS THE REGION. THE COMBINATION OF WET ROADWAYS AND
TEMPS DROPPING WELL BELOW FREEZING WILL SET THE STAGE FOR A
RE-FREEZE TONIGHT. THE MAIN/HEAVILY TRAVELED ROADS SHOULD BE OK
DUE TO THEM DRYING OUT WITH THE HIGHER TRAFFIC VOLUME.
HOWEVER...SECONDARY LESS TRAVELED ROADS AND NEIGHBORHOOD STREETS
COULD BE QUITE ICY IN THE MORNING. WILL BE HIGHLIGHT THIS RISK IN
THE HAZARDOUS WEATHER OUTLOOK THIS AFTERNOON.
FOR TUESDAY...THE DAY WILL LIKELY START OFF MOSTLY CLOUDY WITH
SCATTERED SNOW SHOWERS/FLURRIES DOTTING THE LANDSCAPE. AS VORT MAX
MOVES TO OUR SOUTH AND SOUTHEAST...NORTHWEST FLOW SHOULD PROMOTE
SCATTERED SNOW SHOWERS AND FLURRIES ACROSS THE REGION. FEEL THAT
BEST CHANCES OF FLURRIES WILL BE ACROSS OUR TOPOGRAPHICALLY FAVORED
BLUEGRASS REGION. GENERALLY WENT CLOSE TO A BLEND OF THE NAM AND GFS
RAW GUIDANCE FOR HIGHS. AFTERNOON HIGHS IN THE LOWER 20S IN THE
NORTHEAST/BLUEGRASS TO THE MID AND UPPER 20S IN THE SOUTHWEST ARE
EXPECTED.
.LONG TERM (TUESDAY NIGHT THROUGH MONDAY)...
TUE NIGHT THRU THU NIGHT...
DRY THRUOUT AND AFTER A COLD TUE NIGHT...A WARMING TREND THRU THE
PERIOD.
WE START ON THE BACKSIDE OF A DEEP TROF TUE NIGHT AND TRANSITION TO
ZONAL FLO BY LATE THU AS FLO BACKS FROM NLY TO WLY. A RIDGE OF HI
PRES EXTENDING FROM SRN TEXAS INTO THE MID MS VLY WILL MOVE ACRS OUR
FA TUE NIGHT RESULTING IN ANOTHER NIGHT WITH MINIMUM TEMPS MOSTLY IN
THE TEENS. A WARMING TREND BEGINS WED AS WINDS BECOME SW IN ADVANCE
OF A WEAK TROF OF LOW PRES THAT WASHES OUT BEFORE REACHING OUR AREA.
WARMING WILL CONTINUE INTO THU IN SW FLO WITH HIGH PRES POSITIONED
ACRS THE GULF AND LOW PRES EVOLVING OVER THE SRN PLAINS.
MAX TEMPS SHUD BE ABOUT 10 DEGS WARMER ON SUCCEEDING DAYS STARTING
WED WITH MAXS REACHING THE MID TO UPPER 40S ON THU.
FRI THRU MON...
WILL MAINLY FOLLOW THE MORE CONSISTENT EURO/EURO ENSEMBLES...FAVORED
BY HPC WITH THE 12Z GFS RUN CLOSER TO THE 00Z EURO.
WE TRANSITION FROM A WNW UPPER LEVEL FLOW PATTERN THRU MUCH OF THE
PERIOD TO WSW BY MON...WHEN IT APPEARS THE MOST SIGNIFICANT CHC FOR
PCPN WILL OCCUR. WILL KEEP LOW CHC POPS IN FOR FRI (RAIN) WITH A
COLD FROPA AND THEN CHANGE PRECIP TYPE TO SNOW FOR FRI NIGHT AS A
WAVE DEVELOPS ON THE FRONT AS IT REACHES THE TN VALLEY. WILL ADD A
CHC FOR SNOW SHOWERS SAT IN THE POST COLD FRONTAL AMS AS AN UPPER
TROF DROPS SEWD INTO THE OH VLY.
HI PRES DROPPING ESE FROM THE MID/UPR MS VLY SHUD PROVIDE DRY...
ALBEIT COLD WX FOR SAT NIGHT AND SUN AS THE HIGH MOVES ACRS THE OH
VLY TO THE MID ATLANTIC STATES BY SUN EVE. AFOREMENTIONED UPR LEVEL
FLO BACKS TO WSW MON AS A BROAD TROF EVOLVES OVER THE NATIONS
MID-SECTION BY MON NIGHT. WARM/MOIST ADVECTION/OVERRUNNING BEGINS
SUN NIGHT RESULTING IN A CHC OF RAIN OR SNOW LATE. ALL PRECIP SHUD
TRANSITION TO LIQUID MON WITH THE BEST CHC OF PRECIP AT THIS TIME AS
UPR TROF DEVELOPS UPSTREAM AND A WARM FRONT MOVES THRU. FORCING FOR
ASCENT CONTS MON NIGHT AS A CDFNT MOVES INTO OUR FA. A CHECK OF TIME
HEIGHT CROSS SECTIONS FROM THE 00Z EURO/12Z GFS REVEAL THAT PRECIP
WILL LIKELY START AS SNOW LATE SUN NIGHT OR EARLY MON...THEN CHANGE
TO RAIN BY MON AFTN. FROM A PATTERN RECOGNITION STANDPOINT...MOST
LIKELY SCENARIO IS PRE-WARM FRONT SNOW WITH A TRANSITION TO LIQUID
AFTER FRONTAL PASSAGE. AT THIS POINT...WILL NOT GET TOO DETAILED IN
THE FCST.
GENERALLY FAVORED THE COLDER TEMPS FROM THE EURO/HPC THRU THE
PERIOD...THIS IN LINE WITH THE NEW 12Z GFS.
&&
.AVIATION (18Z TAFS)...
REGIONAL SATELLITE VIEW AND OBSERVATIONS SHOWING MOSTLY CLEAR SKIES
AT KSDF AND KLEX. VFR CONDITIONS ARE EXPECTED AT KSDF/KLEX FOR THE
REMAINDER OF THE AFTERNOON AND EVENING. SFC WINDS WILL BE GENERALLY
FROM THE NW (330-340 DEG) AT 6 TO 8 KTS. KBWG WILL SEE CONDITIONS
IMPROVE RAPIDLY OVER THE NEXT HOUR OR TWO. CLEARING LINE IS JUST
NORTH OF THE REGION AND SNOW FLURRY/SHOWER ACTIVITY WILL HAVE ENDED
BY TAF ISSUANCE TIME. CURRENT MVFR CONDITIONS WILL IMPROVE TO VFR
AND WILL REMAIN VFR THROUGH THE AFTERNOON AND INTO THE EVENING.
WINDS AT KBWG WILL BE NW (330-340 DEG) AT 7-9 KTS THROUGH THE
AFTERNOON AND EVENING.
FOR THE OVERNIGHT PERIOD...LATEST SHORT TERM MODEL GUIDANCE SHOWING
THE UPPER LEVEL TROF OVER US BECOMING A BIT MORE UPRIGHT/NEUTRAL
TILTED (MORE NORTH-SOUTH ORIENTED) OVERNIGHT. THERE IS AN UPPER
LEVEL VORT MAX THAT IS FORECAST TO DIVE STRAIGHT SOUTH FROM
WISCONSIN INTO FAR WEST KY AND THEN DOWN INTO AR...NORTHERN MS/AL
AND THEN INTO THE CAROLINAS. AT THE SAME TIME...WEAK SFC TROF WILL
ACCOMPANY THIS SYSTEM AND MAY PROVIDE ENOUGH LIFT FOR SOME LIGHT
SNOWS ACROSS THE REGION. AT THIS TIME...INTENSITY DOES NOT LOOK AS
GREAT AS WHAT WE SAW LAST NIGHT AND AMOUNTS ARE EXPECTED TO BE MUCH
LIGHTER. IN GENERAL...IT APPEARS THAT VFR CONDITIONS WILL DROP BACK
INTO THE MVFR CATS DUE LOWER CIGS AND VSBY DUE TO LIGHT SNOW AFTER
20/03Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....DK
AVIATION.....MJ
000
FXUS63 KLMK 191118
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
554 AM EST MON JAN 19 2009
.SHORT TERM (TODAY AND TONIGHT)...
WELL MOST PLACES FROM SOUTHERN INDIANA TO LOUISVILLE TO LEXINGTON
HAVE HAD BETWEEN A HALF INCH TO ONE INCH OF SNOW FROM LAST NIGHT
THROUGH EARLY THIS MORNING. A SECOND SMALLER BATCH MOVING THROUGH
SOUTHERN INDIANA AT 730Z THIS MORNING WILL CONTINUE TO DROP UP TO
AN ADDITIONAL HALF INCH OF SNOW THIS MORNING MAKING SNOW TOTALS
FOR SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS BETWEEN 0.5
TO 1.5 INCHES. WILL CONTINUE PRECIP CHANCES THROUGH THE MORNING
HOURS HERE.
ANOTHER AREA OF SNOW STRETCHING FROM SW INDIANA TO BOWLING GREEN
THROUGH SOUTH CENTRAL KY WAS CONTINUE TO MOVE ESE THIS MORNING.
THIS AREA OF SOUTHERN KY DID NOT RECEIVE ANY ACCUMULATING SNOWS
LAST NIGHT...SO EXPECTING MAINLY UP TO A HALF INCH OF SNOW OUT OF
THE LIGHT SCATTERED SNOW SHOWERS FALLING THERE THIS MORNING.
WILL BE CONTINUING AN SPS FOR ALL AREAS AS SOME ROADS OVER THE
NORTH FORECAST AREA ARE SNOW COVERED AND LIGHT SNOW WILL PROBABLY
CAUSE SLICK SPOTS OVER THE SOUTH FA.
AFTER THIS WAVE MOVES THROUGH THIS MORNING...EXPECT FLURRIES OR
PERHAPS A STRAY SNOW SHOWER THIS AFTERNOON. HIGH TEMPS WILL REACH
THE UPPERS 20S TO LOWER 30S. SIDED WITH COOLER FWC MODEL FOR TEMPS
BECAUSE OF SNOW COVER ESPECIALLY OVER THE NORTHERN FA.
TONIGHT AN UPPER LEVEL TROUGH AXIS WILL SWING THROUGH THE AREA.
ALTHOUGH 0Z MODELS ARE NOT VERY OPTIMISTIC QPF WISE WITH THIS
SYSTEM...HAVE LEFT 30-40 POPS IN ANYWAY. MODELS HAVE NOT BEEN
DOING WELL IN THE NW FLOW. TO THE GFS CREDIT...IT DID PICK UP WELL
ON LAST NIGHT/S WAVE AT THE 6Z RUN. SOMETHING TO WATCH FOR WITH
TONIGHT/S FORECAST. HAVE BACKED OFF ON QPF AND SNOW AMOUNTS WITH
THE WAVE TONIGHT GIVING A FEW TENTHS OF SNOW OVER THE EAST FA AND
ONLY A TRACE TO A TENTH ELSEWHERE. LOW TEMPS SHOULD DROP INTO THE
MID TEENS TO AROUND 20 TONIGHT.
.LONG TERM (TUESDAY THROUGH SUNDAY)...
TUESDAY CONTINUES TO SEE THE MODELS PROG A PROLONGED PERIOD OF WARM
AIR ADVECTION IN ASSOCIATION WITH UPSLOPE FLOW ALONG THE EASTERN
TIER OF COUNTIES FOR WHAT MAY TURN OUT TO BE A LONG PERIOD OF HIGH
POP/LOW QPF LIGHT SNOW. MODELS ARE ALSO CONTINUING TO ADVECT A GOOD
STREAM OF LAKE MOISTURE INTO THAT NORTHWEST FLOW THOUGH CURRENT
RADAR TRENDS WOULD INDICATE THE MODELS HAVE YET TO CATCH UP ON
SIGNIFICANT ICE INCREASE ON THE GREAT LAKES FROM LAST WEEKS ARCTIC
SURGE. THUS CURRENT THINKING IS THAT THE MODELS ARE BRINGING IN TOO
MUCH MOISTURE FROM THE LAKES AND WILL TREND BACK ON QPF FOR THE
TUESDAY PERIOD. FLOW SHIFTS SLIGHTLY TO THE WEST IN THE AFTERNOON
AND EARLY EVENING...WHICH MAY SHIFT ANY LIGHT SNOW MORE TO THE
NORTHEAST TOWARD OHIO AS WELL FOR TUESDAY AFTERNOON AND ANYTHING
THAT LINGERS INTO THE EVENING. REGARDLESS...AT THIS TIME CONFIDENCE
IN THE POTENTIAL FOR PROLONGED SNOW REMAINS LOW AND WILL CONTINUE
CARRYING CHANCE POPS FOR TUESDAY AT THIS TIME.
AIR MASS DRIES QUICKLY LATE TUESDAY NIGHT AND WEDNESDAY AS THE UPPER
FLOW BEGINS TO SHIFT MORE TOWARD THE WEST....BEFORE BECOMING ZONAL
THURSDAY AND THURSDAY NIGHT. THIS WILL ALLOW FOR SLIGHTLY MODERATING
TEMPERATURES AND GRADUALLY DECREASING CLOUD COVER. AREAS WITHOUT
SNOW COVER WILL BOTH CLEAR OUT AND MODERATE SLOWER THAN AREAS THAT
DO...MEANING THE EASTERN ZONES SHOULD SEE COOLER HIGHS THAN WESTERN
LOCATIONS FOR WEDNESDAY AND THURSDAY AFTERNOON.
PREVIOUS DISCUSSION FOR THE FRIDAY-SUNDAY PERIOD...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (12Z TAFS)...
LIGHT SNOW WILL CONTINUE OVER THE TAF SITES FOR THE NEXT HOUR OR TWO
CAUSING MVFR/IFR VSBYS AND MVFR CIGS AT TIMES. HOWEVER...CLEARING
IS ON THE WAY IN SOUTHERN INDIANA. CLEARING SHOULD ARRIVE AT SDF
AND LEX BY 13Z OR SHORTLY AFTER...BWG BY ABOUT 16Z. EXPECT ONLY A
FEW MID CLOUDS THIS AFTERNOON WITH NNW WINDS UNDER 10KTS. A FLURRY
OR TWO CANNOT BE RULED OUT ALSO.
TONIGHT ANOTHER WAVE WILL CROSS THE AREA POSSIBLY GENERATING SNOW
SHOWERS NEAR SDF AND LEX. HAVE INSERTED VCSH FOR THESE TERMINALS.
MVFR CIGS SHOULD MAKE THEIR WAY BACK INTO THE TERMINALS TONIGHT
AFTER 3Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...AML
LONG TERM....MACZKO/MJ
AVIATION.....AML
000
FXUS63 KLMK 190752
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
252 AM EST MON JAN 19 2009
.SHORT TERM (TODAY AND TONIGHT)...
WELL MOST PLACES FROM SOUTHERN INDIANA TO LOUISVILLE TO LEXINGTON
HAVE HAD BETWEEN A HALF INCH TO ONE INCH OF SNOW FROM LAST NIGHT
THROUGH EARLY THIS MORNING. A SECOND SMALLER BATCH MOVING THROUGH
SOUTHERN INDIANA AT 730Z THIS MORNING WILL CONTINUE TO DROP UP TO
AN ADDITIONAL HALF INCH OF SNOW THIS MORNING MAKING SNOW TOTALS
FOR SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS BETWEEN 0.5
TO 1.5 INCHES. WILL CONTINUE PRECIP CHANCES THROUGH THE MORNING
HOURS HERE.
ANOTHER AREA OF SNOW STRETCHING FROM SW INDIANA TO BOWLING GREEN
THROUGH SOUTH CENTRAL KY WAS CONTINUE TO MOVE ESE THIS MORNING.
THIS AREA OF SOUTHERN KY DID NOT RECEIVE ANY ACCUMULATING SNOWS
LAST NIGHT...SO EXPECTING MAINLY UP TO A HALF INCH OF SNOW OUT OF
THE LIGHT SCATTERED SNOW SHOWERS FALLING THERE THIS MORNING.
WILL BE CONTINUING AN SPS FOR ALL AREAS AS SOME ROADS OVER THE
NORTH FORECAST AREA ARE SNOW COVERED AND LIGHT SNOW WILL PROBABLY
CAUSE SLICK SPOTS OVER THE SOUTH FA.
AFTER THIS WAVE MOVES THROUGH THIS MORNING...EXPECT FLURRIES OR
PERHAPS A STRAY SNOW SHOWER THIS AFTERNOON. HIGH TEMPS WILL REACH
THE UPPERS 20S TO LOWER 30S. SIDED WITH COOLER FWC MODEL FOR TEMPS
BECAUSE OF SNOW COVER ESPECIALLY OVER THE NORTHERN FA.
TONIGHT AN UPPER LEVEL TROUGH AXIS WILL SWING THROUGH THE AREA.
ALTHOUGH 0Z MODELS ARE NOT VERY OPTIMISTIC QPF WISE WITH THIS
SYSTEM...HAVE LEFT 30-40 POPS IN ANYWAY. MODELS HAVE NOT BEEN
DOING WELL IN THE NW FLOW. TO THE GFS CREDIT...IT DID PICK UP WELL
ON LAST NIGHT/S WAVE AT THE 6Z RUN. SOMETHING TO WATCH FOR WITH
TONIGHT/S FORECAST. HAVE BACKED OFF ON QPF AND SNOW AMOUNTS WITH
THE WAVE TONIGHT GIVING A FEW TENTHS OF SNOW OVER THE EAST FA AND
ONLY A TRACE TO A TENTH ELSEWHERE. LOW TEMPS SHOULD DROP INTO THE
MID TEENS TO AROUND 20 TONIGHT.
.LONG TERM (TUESDAY THROUGH SUNDAY)...
TUESDAY CONTINUES TO SEE THE MODELS PROG A PROLONGED PERIOD OF WARM
AIR ADVECTION IN ASSOCIATION WITH UPSLOPE FLOW ALONG THE EASTERN
TIER OF COUNTIES FOR WHAT MAY TURN OUT TO BE A LONG PERIOD OF HIGH
POP/LOW QPF LIGHT SNOW. MODELS ARE ALSO CONTINUING TO ADVECT A GOOD
STREAM OF LAKE MOISTURE INTO THAT NORTHWEST FLOW THOUGH CURRENT
RADAR TRENDS WOULD INDICATE THE MODELS HAVE YET TO CATCH UP ON
SIGNIFICANT ICE INCREASE ON THE GREAT LAKES FROM LAST WEEKS ARCTIC
SURGE. THUS CURRENT THINKING IS THAT THE MODELS ARE BRINGING IN TOO
MUCH MOISTURE FROM THE LAKES AND WILL TREND BACK ON QPF FOR THE
TUESDAY PERIOD. FLOW SHIFTS SLIGHTLY TO THE WEST IN THE AFTERNOON
AND EARLY EVENING...WHICH MAY SHIFT ANY LIGHT SNOW MORE TO THE
NORTHEAST TOWARD OHIO AS WELL FOR TUESDAY AFTERNOON AND ANYTHING
THAT LINGERS INTO THE EVENING. REGARDLESS...AT THIS TIME CONFIDENCE
IN THE POTENTIAL FOR PROLONGED SNOW REMAINS LOW AND WILL CONTINUE
CARRYING CHANCE POPS FOR TUESDAY AT THIS TIME.
AIR MASS DRIES QUICKLY LATE TUESDAY NIGHT AND WEDNESDAY AS THE UPPER
FLOW BEGINS TO SHIFT MORE TOWARD THE WEST....BEFORE BECOMING ZONAL
THURSDAY AND THURSDAY NIGHT. THIS WILL ALLOW FOR SLIGHTLY MODERATING
TEMPERATURES AND GRADUALLY DECREASING CLOUD COVER. AREAS WITHOUT
SNOW COVER WILL BOTH CLEAR OUT AND MODERATE SLOWER THAN AREAS THAT
DO...MEANING THE EASTERN ZONES SHOULD SEE COOLER HIGHS THAN WESTERN
LOCATIONS FOR WEDNESDAY AND THURSDAY AFTERNOON.
PREVIOUS DISCUSSION FOR THE FRIDAY-SUNDAY PERIOD...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (06Z TAFS)...
SMALL UPPER DISTURBANCES ARE FALLING INTO THE UPPER MISSISSIPPI
VALLEY THIS EVENING AND WILL MAKE THE LEFT TURN THROUGH THE EASTERN
U.S. UPPER TROF TONIGHT. LIGHT SNOW FALLING FROM SOUTHEAST MINNESOTA
TO CENTRAL ILLINOIS THIS AFTERNOON WILL SLIDE TO THE SOUTHEAST AND
WILL AFFECT THE TAF SITES OVERNIGHT...ESPECIALLY SDF AND LEX.
FLURRIES CAN BE EXPECTED THIS EVENING...THEN A MORE STEADY LIGHT
SNOW BEGINNING AROUND MIDNIGHT OR SO. CEILINGS THAT ARE ALREADY MVFR
WILL CONTINUE...AND IN THE SOUTH VFR CEILINGS THIS EVENING WILL SINK
INTO MVFR CATEGORY AS THE LIGHT SNOW APPROACHES. WILL KEEP
PREVAILING VSBYS VFR FOR NOW...WITH SOME OCCASIONAL IFR VSBYS
POSSIBLE IN SNOW SHOWERS AT SDF AND LEX DURING THE OVERNIGHT HOURS.
THE MOISTURE LEAVES THE REGION BY MID MORNING MONDAY BRINGING AN END
TO THE LIGHT SNOW BY AROUND 15Z. WILL HANG ON TO MVFR CEILINGS
THROUGH THE DAY HOWEVER. SOME MODEL SOLUTIONS SUGGEST EITHER A VFR
CEILING OR POSSIBLY EVEN LOSING THE CEILING MONDAY AFTERNOON...BUT
IN THIS SORT OF FLOW UNDER THE UPPER TROF WOULD RATHER GO MORE
PESSIMISTIC THAN OPTIMISTIC.
ANOTHER WAVE DROPS SOUTH MONDAY EVENING BUT RIGHT NOW IT LOOKS LIKE
ANY SNOW FROM THIS SECOND SYSTEM WILL REMAIN WELL TO THE WEST OF SDF.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...AML
LONG TERM....MACZKO/MJ
AVIATION.....AML
000
FXUS63 KLMK 190516
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1215 AM EST MON JAN 19 2009
.UPDATE...
TWO AREAS OF SNOW TO CONCERN OURSELVES WITH TONIGHT. THE FIRST ONE
IS MOVING THROUGH SOUTHERN INDIANA AND NORTHERN KENTUCKY RIGHT NOW.
THIS AREA OF SNOW WILL LIKELY PRODUCE THREE QUARTERS OF AN INCH TO
AROUND AN INCH OF ACCUMULATION. HAVE UPDATED THE FORECAST TO REFLECT
THIS. SECOND AREA OF SNOW IS STILL OVER CENTRAL ILLINOIS AND WILL BE
MOVING INTO THE AREA DURING THE LATE NIGHT HOURS AND INTO MONDAY
MORNING. THAT AREA OF SNOW SHOULD COME THROUGH OUR REGION JUST A BIT
FURTHER TO THE SOUTH. SO...WILL HAVE A FORECAST OF AN INCH OF
ACCUMULATION THROUGHOUT THE CWFA...WITH THE BEST CHANCES FOR THE
MOST SIGNIFICANT SNOWFALL LIKELY ALONG THE BLUEGRASS PARKWAY AND
I-64 CORRIDORS. AFTER COORDINATION...WILL CONTINUE TO HANDLE THINGS
WITH SPECIAL WEATHER STATEMENTS FOR NOW. IF THE SECOND AREA OF SNOW
OVER CENTRAL ILLINOIS STRENGTHENS OR LOOKS LIKE IT WILL GO OVER THE
EXACT SAME AREAS AS THE FIRST BATCH THIS EVENING AN ADVISORY MAY
THEN BE NEEDED.
NO OTHER SIGNIFICANT CHANGES TO THE FORECAST.
MANY THANKS TO ALL THE SPOTTERS AND COCORAHS OBSERVERS FOR THE
SNOWFALL REPORTS YOU HAVE BEEN SENDING US TONIGHT!
.SHORT TERM (TONIGHT AND MONDAY)...
LARGE SCALE H5 TROF CONTINUES TO BE SITUATED ACROSS THE EASTERN
U.S. SERIES OF VORTICITY LOBES CONTINUE TO ROTATE THROUGH WITHIN
THE MEAN FLOW. ONE OF THESE IS CURRENTLY MOVING THROUGH THE EASTERN
HALF OF THE REGION BRINGING A PERIOD OF LIGHT SNOW TO THE REGION.
WITH TEMPERATURES UP NEAR OR JUST ABOVE FREEZING...ACCUMULATIONS
HAVE BEEN GENERALLY NIL WITH A DUSTING HERE AND THERE. THIS SNOW
SHOWER ACTIVITY WILL CONTINUE TO PRESS SOUTHEAST INTO EASTERN KY
THIS AFTERNOON AND EVENING. AS THIS MOVES OUT...WE`LL BE IN A LULL
FOR A WHILE UNTIL THE NEXT VORT COMES DOWN LATER TONIGHT. IN
FACT...WOULD NOT BE SURPRISED TO SEE SOME BREAKS IN THE OVERCAST FOR
A TIME THIS AFTERNOON AND EVENING.
CURRENT WATER VAPOR IMAGERY SHOWING OUR VORT LOBE OF NOTE NOW
LOCATED UP ACROSS WISCONSIN AND MOVING QUICKLY TO THE SOUTH. ALL OF
THE SHORT TERM MODEL SOLUTIONS BRING THIS LOBE SOUTH INTO WEST KY
AND THEN A SHARP TURN TO THE EAST AS THE LOBE GOES INTO THE BASE OF
THE UPPER TROUGH. CURRENTLY...THIS LOBE IS PRODUCING A DECENT
AMOUNT OF SNOW ACROSS WISCONSIN AND EXPECT PRECIPITATION SHIELD TO
BE A GOOD SIZE AS IT MOVES THROUGH TONIGHT. WILL BE RAISING POPS
SIGNIFICANTLY AS EXPECT SNOW SHOWER COVERAGE TO BE QUITE LARGE. AS
THIS SYSTEM CROSSES INTO OUR REGION...SOME LOCAL ENHANCEMENT DUE TO
TOPOGRAPHIC EFFECTS ARE POSSIBLE. WITH THAT SAID...ACTUAL BEST
SNOWFALL ACCUMULATION POTENTIAL WILL BE ACROSS THE SOUTH...MAINLY
SOUTH OF THE WESTERN KY AND BLUEGRASS PARKWAYS. IN THAT
AREA...AROUND ONE INCH OF ACCUMULATION LOOKS LIKELY. THOUGH SOME
AREA MAY SEE LOCALIZED HIGHER AMOUNTS. NORTH OF THE
PARKWAYS...BETWEEN A HALF AND ONE INCH LOOKS LIKELY.
AFTER COORDINATING WITH SURROUNDING OFFICES...WE`LL BE HOLDING OFF
ON AN ADVISORY AT THIS TIME...AS BEST ACCUMULATIONS LOOK TO BE JUST
TO OUR SOUTHEAST...WHERE MORE TOPOGRAPHIC LIFT WILL ENHANCE THE
SNOWFALL ACTIVITY. HOWEVER...WE WILL CONTINUE TO WATCH UPSTREAM
OBSERVATIONS AND SNOWFALL AMOUNTS AND IF THE SYSTEM APPEARS STRONGER
THAN FORECAST AN ADVISORY MAY BE REQUIRED LATER THIS EVENING. IN
THE MEANTIME...WE WILL ISSUE A SPECIAL WEATHER STATEMENT
HIGHLIGHTING THE WINTER WEATHER POTENTIAL.
AS THIS SNOWBAND PUSHES SOUTHEAST OVERNIGHT...MUCH COLDER AIR WILL
PUSH IN BEHIND THE SYSTEM. OVERNIGHT LOWS WILL DROP INTO THE MID
AND UPPER TEENS ACROSS THE NORTH WITH LOWER 20S ACROSS THE FAR SOUTH.
FOR MONDAY...AS VORT LOBE PUSHES OFF TO THE EAST AS IT ROUNDS THE
BASE OF THE UPPER TROF...SOME SNOW SHOWERS WILL CONTINUE TO BE
POSSIBLE DURING THE MORNING HOURS...ESPECIALLY ACROSS THE EASTERN
SECTIONS. MOISTURE LOOKS TO DEPART QUICKLY...BUT NORTHWEST FLOW AND
STEEP LAPSE RATES SHOULD PROMOTE SCATTERED FLURRIES THROUGH THE
REMAINDER OF THE AFTERNOON. TEMPERATURES WILL BE TRICKY DEPENDING
ON SNOW ACCUMULATIONS. GIVEN THAT WE`RE EXPECTING SOME LIGHT
ACCUMULATIONS...WILL BE TRIMMING TEMPS UNDER GUIDANCE WITH HIGHS IN
THE MID TO UPPER 20S.
.LONG TERM (MONDAY NIGHT THROUGH SUNDAY)...
TROUGHING OVER THE ERN HALF OF THE CONUS WILL CONTINUE TO AFFECT US
FOR MOST OF THIS PERIOD. AN UPPER LEVEL DISTURBANCE ON THE BACK SIDE
OF THE MAIN TROUGH WILL ROTATE DOWN MONDAY NIGHT AND SHOULD PRODUCE
LIGHT SNOW SHOWERS ACROSS THE AREA. AGAIN THIS LOOKS LIKE A HIGH CHC
LOW QPF SITUATION...SO AT THIS POINT WILL CONTINUE THE 30-40 PERCENT
POPS...WITH THE BEST CHANCE OVER THE E/SE CWA MON NIGHT - TUES. WITH
THE GROUNDS BEING COLD ENOUGH...MAY ACTUALLY GET LIGHT ACCUMS OVER
THE ERN/SRN CWA. BEST CHANCE IS OVER THE SRN BLUEGRASS...HAVE LESS
THAN HALF AN INCH IN THE GRIDS THROUGH TUESDAY. BECAUSE OF
THIS...WENT A BIT BELOW MOS GUIDANCE OVER THE EAST...WITH TEENS FOR
LOW MON AND TUES NIGHTS...AND HIGHS TUESDAY IN THE MID 20S NE TO
NEAR FREEZING SW. POPS SHOULD END OVER THE EAST BY TUESDAY NIGHT.
WEDNESDAY-THURSDAY NIGHT...
THE UPPER-LEVEL FLOW FLATTENS OUT DURING THIS PERIOD AS NORTHWEST
FLOW MOVES OFF TO THE EAST. TEMPS WILL MODERATE BACK TO NEAR 40 ON
WED AND THEN TO THE UPPER 40S TO LOW 50S THURSDAY AHEAD OF THE NEXT
SYSTEM. THIS PERIOD SHOULD BE DRY.
FRIDAY-SUNDAY...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (06Z TAFS)...
SMALL UPPER DISTURBANCES ARE FALLING INTO THE UPPER MISSISSIPPI
VALLEY THIS EVENING AND WILL MAKE THE LEFT TURN THROUGH THE EASTERN
U.S. UPPER TROF TONIGHT. LIGHT SNOW FALLING FROM SOUTHEAST MINNESOTA
TO CENTRAL ILLINOIS THIS AFTERNOON WILL SLIDE TO THE SOUTHEAST AND
WILL AFFECT THE TAF SITES OVERNIGHT...ESPECIALLY SDF AND LEX.
FLURRIES CAN BE EXPECTED THIS EVENING...THEN A MORE STEADY LIGHT
SNOW BEGINNING AROUND MIDNIGHT OR SO. CEILINGS THAT ARE ALREADY MVFR
WILL CONTINUE...AND IN THE SOUTH VFR CEILINGS THIS EVENING WILL SINK
INTO MVFR CATEGORY AS THE LIGHT SNOW APPROACHES. WILL KEEP
PREVAILING VSBYS VFR FOR NOW...WITH SOME OCCASIONAL IFR VSBYS
POSSIBLE IN SNOW SHOWERS AT SDF AND LEX DURING THE OVERNIGHT HOURS.
THE MOISTURE LEAVES THE REGION BY MID MORNING MONDAY BRINGING AN END
TO THE LIGHT SNOW BY AROUND 15Z. WILL HANG ON TO MVFR CEILINGS
THROUGH THE DAY HOWEVER. SOME MODEL SOLUTIONS SUGGEST EITHER A VFR
CEILING OR POSSIBLY EVEN LOSING THE CEILING MONDAY AFTERNOON...BUT
IN THIS SORT OF FLOW UNDER THE UPPER TROF WOULD RATHER GO MORE
PESSIMISTIC THAN OPTIMISTIC.
ANOTHER WAVE DROPS SOUTH MONDAY EVENING BUT RIGHT NOW IT LOOKS LIKE
ANY SNOW FROM THIS SECOND SYSTEM WILL REMAIN WELL TO THE WEST OF SDF.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE...13
SHORT TERM...MJ
LONG TERM....ADL
AVIATION.....13/AML
000
FXUS63 KLMK 190320
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1020 PM EST SUN JAN 18 2009
.UPDATE...
TWO AREAS OF SNOW TO CONCERN OURSELVES WITH TONIGHT. THE FIRST ONE
IS MOVING THROUGH SOUTHERN INDIANA AND NORTHERN KENTUCKY RIGHT NOW.
THIS AREA OF SNOW WILL LIKELY PRODUCE THREE QUARTERS OF AN INCH TO
AROUND AN INCH OF ACCUMULATION. HAVE UPDATED THE FORECAST TO REFLECT
THIS. SECOND AREA OF SNOW IS STILL OVER CENTRAL ILLINOIS AND WILL BE
MOVING INTO THE AREA DURING THE LATE NIGHT HOURS AND INTO MONDAY
MORNING. THAT AREA OF SNOW SHOULD COME THROUGH OUR REGION JUST A BIT
FURTHER TO THE SOUTH. SO...WILL HAVE A FORECAST OF AN INCH OF
ACCUMULATION THROUGHOUT THE CWFA...WITH THE BEST CHANCES FOR THE
MOST SIGNIFICANT SNOWFALL LIKELY ALONG THE BLUEGRASS PARKWAY AND
I-64 CORRIDORS. AFTER COORDINATION...WILL CONTINUE TO HANDLE THINGS
WITH SPECIAL WEATHER STATEMENTS FOR NOW. IF THE SECOND AREA OF SNOW
OVER CENTRAL ILLINOIS STRENGTHENS OR LOOKS LIKE IT WILL GO OVER THE
EXACT SAME AREAS AS THE FIRST BATCH THIS EVENING AN ADVISORY MAY
THEN BE NEEDED.
NO OTHER SIGNIFICANT CHANGES TO THE FORECAST.
MANY THANKS TO ALL THE SPOTTERS AND COCORAHS OBSERVERS FOR THE
SNOWFALL REPORTS YOU HAVE BEEN SENDING US TONIGHT!
.SHORT TERM (TONIGHT AND MONDAY)...
LARGE SCALE H5 TROF CONTINUES TO BE SITUATED ACROSS THE EASTERN
U.S. SERIES OF VORTICITY LOBES CONTINUE TO ROTATE THROUGH WITHIN
THE MEAN FLOW. ONE OF THESE IS CURRENTLY MOVING THROUGH THE EASTERN
HALF OF THE REGION BRINGING A PERIOD OF LIGHT SNOW TO THE REGION.
WITH TEMPERATURES UP NEAR OR JUST ABOVE FREEZING...ACCUMULATIONS
HAVE BEEN GENERALLY NIL WITH A DUSTING HERE AND THERE. THIS SNOW
SHOWER ACTIVITY WILL CONTINUE TO PRESS SOUTHEAST INTO EASTERN KY
THIS AFTERNOON AND EVENING. AS THIS MOVES OUT...WE`LL BE IN A LULL
FOR A WHILE UNTIL THE NEXT VORT COMES DOWN LATER TONIGHT. IN
FACT...WOULD NOT BE SURPRISED TO SEE SOME BREAKS IN THE OVERCAST FOR
A TIME THIS AFTERNOON AND EVENING.
CURRENT WATER VAPOR IMAGERY SHOWING OUR VORT LOBE OF NOTE NOW
LOCATED UP ACROSS WISCONSIN AND MOVING QUICKLY TO THE SOUTH. ALL OF
THE SHORT TERM MODEL SOLUTIONS BRING THIS LOBE SOUTH INTO WEST KY
AND THEN A SHARP TURN TO THE EAST AS THE LOBE GOES INTO THE BASE OF
THE UPPER TROUGH. CURRENTLY...THIS LOBE IS PRODUCING A DECENT
AMOUNT OF SNOW ACROSS WISCONSIN AND EXPECT PRECIPITATION SHIELD TO
BE A GOOD SIZE AS IT MOVES THROUGH TONIGHT. WILL BE RAISING POPS
SIGNIFICANTLY AS EXPECT SNOW SHOWER COVERAGE TO BE QUITE LARGE. AS
THIS SYSTEM CROSSES INTO OUR REGION...SOME LOCAL ENHANCEMENT DUE TO
TOPOGRAPHIC EFFECTS ARE POSSIBLE. WITH THAT SAID...ACTUAL BEST
SNOWFALL ACCUMULATION POTENTIAL WILL BE ACROSS THE SOUTH...MAINLY
SOUTH OF THE WESTERN KY AND BLUEGRASS PARKWAYS. IN THAT
AREA...AROUND ONE INCH OF ACCUMULATION LOOKS LIKELY. THOUGH SOME
AREA MAY SEE LOCALIZED HIGHER AMOUNTS. NORTH OF THE
PARKWAYS...BETWEEN A HALF AND ONE INCH LOOKS LIKELY.
AFTER COORDINATING WITH SURROUNDING OFFICES...WE`LL BE HOLDING OFF
ON AN ADVISORY AT THIS TIME...AS BEST ACCUMULATIONS LOOK TO BE JUST
TO OUR SOUTHEAST...WHERE MORE TOPOGRAPHIC LIFT WILL ENHANCE THE
SNOWFALL ACTIVITY. HOWEVER...WE WILL CONTINUE TO WATCH UPSTREAM
OBSERVATIONS AND SNOWFALL AMOUNTS AND IF THE SYSTEM APPEARS STRONGER
THAN FORECAST AN ADVISORY MAY BE REQUIRED LATER THIS EVENING. IN
THE MEANTIME...WE WILL ISSUE A SPECIAL WEATHER STATEMENT
HIGHLIGHTING THE WINTER WEATHER POTENTIAL.
AS THIS SNOWBAND PUSHES SOUTHEAST OVERNIGHT...MUCH COLDER AIR WILL
PUSH IN BEHIND THE SYSTEM. OVERNIGHT LOWS WILL DROP INTO THE MID
AND UPPER TEENS ACROSS THE NORTH WITH LOWER 20S ACROSS THE FAR SOUTH.
FOR MONDAY...AS VORT LOBE PUSHES OFF TO THE EAST AS IT ROUNDS THE
BASE OF THE UPPER TROF...SOME SNOW SHOWERS WILL CONTINUE TO BE
POSSIBLE DURING THE MORNING HOURS...ESPECIALLY ACROSS THE EASTERN
SECTIONS. MOISTURE LOOKS TO DEPART QUICKLY...BUT NORTHWEST FLOW AND
STEEP LAPSE RATES SHOULD PROMOTE SCATTERED FLURRIES THROUGH THE
REMAINDER OF THE AFTERNOON. TEMPERATURES WILL BE TRICKY DEPENDING
ON SNOW ACCUMULATIONS. GIVEN THAT WE`RE EXPECTING SOME LIGHT
ACCUMULATIONS...WILL BE TRIMMING TEMPS UNDER GUIDANCE WITH HIGHS IN
THE MID TO UPPER 20S.
.LONG TERM (MONDAY NIGHT THROUGH SUNDAY)...
TROUGHING OVER THE ERN HALF OF THE CONUS WILL CONTINUE TO AFFECT US
FOR MOST OF THIS PERIOD. AN UPPER LEVEL DISTURBANCE ON THE BACK SIDE
OF THE MAIN TROUGH WILL ROTATE DOWN MONDAY NIGHT AND SHOULD PRODUCE
LIGHT SNOW SHOWERS ACROSS THE AREA. AGAIN THIS LOOKS LIKE A HIGH CHC
LOW QPF SITUATION...SO AT THIS POINT WILL CONTINUE THE 30-40 PERCENT
POPS...WITH THE BEST CHANCE OVER THE E/SE CWA MON NIGHT - TUES. WITH
THE GROUNDS BEING COLD ENOUGH...MAY ACTUALLY GET LIGHT ACCUMS OVER
THE ERN/SRN CWA. BEST CHANCE IS OVER THE SRN BLUEGRASS...HAVE LESS
THAN HALF AN INCH IN THE GRIDS THROUGH TUESDAY. BECAUSE OF
THIS...WENT A BIT BELOW MOS GUIDANCE OVER THE EAST...WITH TEENS FOR
LOW MON AND TUES NIGHTS...AND HIGHS TUESDAY IN THE MID 20S NE TO
NEAR FREEZING SW. POPS SHOULD END OVER THE EAST BY TUESDAY NIGHT.
WEDNESDAY-THURSDAY NIGHT...
THE UPPER-LEVEL FLOW FLATTENS OUT DURING THIS PERIOD AS NORTHWEST
FLOW MOVES OFF TO THE EAST. TEMPS WILL MODERATE BACK TO NEAR 40 ON
WED AND THEN TO THE UPPER 40S TO LOW 50S THURSDAY AHEAD OF THE NEXT
SYSTEM. THIS PERIOD SHOULD BE DRY.
FRIDAY-SUNDAY...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (00Z TAFS)...
SMALL UPPER DISTURBANCES ARE FALLING INTO THE UPPER MISSISSIPPI
VALLEY THIS EVENING AND WILL MAKE THE LEFT TURN THROUGH THE EASTERN
U.S. UPPER TROF TONIGHT. LIGHT SNOW FALLING FROM SOUTHEAST MINNESOTA
TO CENTRAL ILLINOIS THIS AFTERNOON WILL SLIDE TO THE SOUTHEAST AND
WILL AFFECT THE TAF SITES OVERNIGHT...ESPECIALLY SDF AND LEX.
FLURRIES CAN BE EXPECTED THIS EVENING...THEN A MORE STEADY LIGHT
SNOW BEGINNING AROUND MIDNIGHT OR SO. CEILINGS THAT ARE ALREADY MVFR
WILL CONTINUE...AND IN THE SOUTH VFR CEILINGS THIS EVENING WILL SINK
INTO MVFR CATEGORY AS THE LIGHT SNOW APPROACHES. WILL KEEP
PREVAILING VSBYS VFR FOR NOW...WITH SOME OCCASIONAL IFR VSBYS
POSSIBLE IN SNOW SHOWERS AT SDF AND LEX DURING THE OVERNIGHT HOURS.
THE MOISTURE LEAVES THE REGION BY MID MORNING MONDAY BRINGING AN END
TO THE LIGHT SNOW BY AROUND 15Z. WILL HANG ON TO MVFR CEILINGS
THROUGH THE DAY HOWEVER. SOME MODEL SOLUTIONS SUGGEST EITHER A VFR
CEILING OR POSSIBLY EVEN LOSING THE CEILING MONDAY AFTERNOON...BUT
IN THIS SORT OF FLOW UNDER THE UPPER TROF WOULD RATHER GO MORE
PESSIMISTIC THAN OPTIMISTIC.
ANOTHER WAVE DROPS SOUTH MONDAY EVENING BUT RIGHT NOW IT LOOKS LIKE
ANY SNOW FROM THIS SECOND SYSTEM WILL REMAIN WELL TO THE WEST OF SDF.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE...13
SHORT TERM...MJ
LONG TERM....ADL
AVIATION.....13
000
FXUS63 KLMK 182305
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
605 PM EST SUN JAN 18 2009
.SHORT TERM (TONIGHT AND MONDAY)...
LARGE SCALE H5 TROF CONTINUES TO BE SITUATED ACROSS THE EASTERN
U.S. SERIES OF VORTICITY LOBES CONTINUE TO ROTATE THROUGH WITHIN
THE MEAN FLOW. ONE OF THESE IS CURRENTLY MOVING THROUGH THE EASTERN
HALF OF THE REGION BRINGING A PERIOD OF LIGHT SNOW TO THE REGION.
WITH TEMPERATURES UP NEAR OR JUST ABOVE FREEZING...ACCUMULATIONS
HAVE BEEN GENERALLY NIL WITH A DUSTING HERE AND THERE. THIS SNOW
SHOWER ACTIVITY WILL CONTINUE TO PRESS SOUTHEAST INTO EASTERN KY
THIS AFTERNOON AND EVENING. AS THIS MOVES OUT...WE`LL BE IN A LULL
FOR A WHILE UNTIL THE NEXT VORT COMES DOWN LATER TONIGHT. IN
FACT...WOULD NOT BE SURPRISED TO SEE SOME BREAKS IN THE OVERCAST FOR
A TIME THIS AFTERNOON AND EVENING.
CURRENT WATER VAPOR IMAGERY SHOWING OUR VORT LOBE OF NOTE NOW
LOCATED UP ACROSS WISCONSIN AND MOVING QUICKLY TO THE SOUTH. ALL OF
THE SHORT TERM MODEL SOLUTIONS BRING THIS LOBE SOUTH INTO WEST KY
AND THEN A SHARP TURN TO THE EAST AS THE LOBE GOES INTO THE BASE OF
THE UPPER TROUGH. CURRENTLY...THIS LOBE IS PRODUCING A DECENT
AMOUNT OF SNOW ACROSS WISCONSIN AND EXPECT PRECIPITATION SHIELD TO
BE A GOOD SIZE AS IT MOVES THROUGH TONIGHT. WILL BE RAISING POPS
SIGNIFICANTLY AS EXPECT SNOW SHOWER COVERAGE TO BE QUITE LARGE. AS
THIS SYSTEM CROSSES INTO OUR REGION...SOME LOCAL ENHANCEMENT DUE TO
TOPOGRAPHIC EFFECTS ARE POSSIBLE. WITH THAT SAID...ACTUAL BEST
SNOWFALL ACCUMULATION POTENTIAL WILL BE ACROSS THE SOUTH...MAINLY
SOUTH OF THE WESTERN KY AND BLUEGRASS PARKWAYS. IN THAT
AREA...AROUND ONE INCH OF ACCUMULATION LOOKS LIKELY. THOUGH SOME
AREA MAY SEE LOCALIZED HIGHER AMOUNTS. NORTH OF THE
PARKWAYS...BETWEEN A HALF AND ONE INCH LOOKS LIKELY.
AFTER COORDINATING WITH SURROUNDING OFFICES...WE`LL BE HOLDING OFF
ON AN ADVISORY AT THIS TIME...AS BEST ACCUMULATIONS LOOK TO BE JUST
TO OUR SOUTHEAST...WHERE MORE TOPOGRAPHIC LIFT WILL ENHANCE THE
SNOWFALL ACTIVITY. HOWEVER...WE WILL CONTINUE TO WATCH UPSTREAM
OBSERVATIONS AND SNOWFALL AMOUNTS AND IF THE SYSTEM APPEARS STRONGER
THAN FORECAST AN ADVISORY MAY BE REQUIRED LATER THIS EVENING. IN
THE MEANTIME...WE WILL ISSUE A SPECIAL WEATHER STATEMENT
HIGHLIGHTING THE WINTER WEATHER POTENTIAL.
AS THIS SNOWBAND PUSHES SOUTHEAST OVERNIGHT...MUCH COLDER AIR WILL
PUSH IN BEHIND THE SYSTEM. OVERNIGHT LOWS WILL DROP INTO THE MID
AND UPPER TEENS ACROSS THE NORTH WITH LOWER 20S ACROSS THE FAR SOUTH.
FOR MONDAY...AS VORT LOBE PUSHES OFF TO THE EAST AS IT ROUNDS THE
BASE OF THE UPPER TROF...SOME SNOW SHOWERS WILL CONTINUE TO BE
POSSIBLE DURING THE MORNING HOURS...ESPECIALLY ACROSS THE EASTERN
SECTIONS. MOISTURE LOOKS TO DEPART QUICKLY...BUT NORTHWEST FLOW AND
STEEP LAPSE RATES SHOULD PROMOTE SCATTERED FLURRIES THROUGH THE
REMAINDER OF THE AFTERNOON. TEMPERATURES WILL BE TRICKY DEPENDING
ON SNOW ACCUMULATIONS. GIVEN THAT WE`RE EXPECTING SOME LIGHT
ACCUMULATIONS...WILL BE TRIMMING TEMPS UNDER GUIDANCE WITH HIGHS IN
THE MID TO UPPER 20S.
.LONG TERM (MONDAY NIGHT THROUGH SUNDAY)...
TROUGHING OVER THE ERN HALF OF THE CONUS WILL CONTINUE TO AFFECT US
FOR MOST OF THIS PERIOD. AN UPPER LEVEL DISTURBANCE ON THE BACK SIDE
OF THE MAIN TROUGH WILL ROTATE DOWN MONDAY NIGHT AND SHOULD PRODUCE
LIGHT SNOW SHOWERS ACROSS THE AREA. AGAIN THIS LOOKS LIKE A HIGH CHC
LOW QPF SITUATION...SO AT THIS POINT WILL CONTINUE THE 30-40 PERCENT
POPS...WITH THE BEST CHANCE OVER THE E/SE CWA MON NIGHT - TUES. WITH
THE GROUNDS BEING COLD ENOUGH...MAY ACTUALLY GET LIGHT ACCUMS OVER
THE ERN/SRN CWA. BEST CHANCE IS OVER THE SRN BLUEGRASS...HAVE LESS
THAN HALF AN INCH IN THE GRIDS THROUGH TUESDAY. BECAUSE OF
THIS...WENT A BIT BELOW MOS GUIDANCE OVER THE EAST...WITH TEENS FOR
LOW MON AND TUES NIGHTS...AND HIGHS TUESDAY IN THE MID 20S NE TO
NEAR FREEZING SW. POPS SHOULD END OVER THE EAST BY TUESDAY NIGHT.
WEDNESDAY-THURSDAY NIGHT...
THE UPPER-LEVEL FLOW FLATTENS OUT DURING THIS PERIOD AS NORTHWEST
FLOW MOVES OFF TO THE EAST. TEMPS WILL MODERATE BACK TO NEAR 40 ON
WED AND THEN TO THE UPPER 40S TO LOW 50S THURSDAY AHEAD OF THE NEXT
SYSTEM. THIS PERIOD SHOULD BE DRY.
FRIDAY-SUNDAY...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (00Z TAFS)...
SMALL UPPER DISTURBANCES ARE FALLING INTO THE UPPER MISSISSIPPI
VALLEY THIS EVENING AND WILL MAKE THE LEFT TURN THROUGH THE EASTERN
U.S. UPPER TROF TONIGHT. LIGHT SNOW FALLING FROM SOUTHEAST MINNESOTA
TO CENTRAL ILLINOIS THIS AFTERNOON WILL SLIDE TO THE SOUTHEAST AND
WILL AFFECT THE TAF SITES OVERNIGHT...ESPECIALLY SDF AND LEX.
FLURRIES CAN BE EXPECTED THIS EVENING...THEN A MORE STEADY LIGHT
SNOW BEGINNING AROUND MIDNIGHT OR SO. CEILINGS THAT ARE ALREADY MVFR
WILL CONTINUE...AND IN THE SOUTH VFR CEILINGS THIS EVENING WILL SINK
INTO MVFR CATEGORY AS THE LIGHT SNOW APPROACHES. WILL KEEP
PREVAILING VSBYS VFR FOR NOW...WITH SOME OCCASIONAL IFR VSBYS
POSSIBLE IN SNOW SHOWERS AT SDF AND LEX DURING THE OVERNIGHT HOURS.
THE MOISTURE LEAVES THE REGION BY MID MORNING MONDAY BRINGING AN END
TO THE LIGHT SNOW BY AROUND 15Z. WILL HANG ON TO MVFR CEILINGS
THROUGH THE DAY HOWEVER. SOME MODEL SOLUTIONS SUGGEST EITHER A VFR
CEILING OR POSSIBLY EVEN LOSING THE CEILING MONDAY AFTERNOON...BUT
IN THIS SORT OF FLOW UNDER THE UPPER TROF WOULD RATHER GO MORE
PESSIMISTIC THAN OPTIMISTIC.
ANOTHER WAVE DROPS SOUTH MONDAY EVENING BUT RIGHT NOW IT LOOKS LIKE
ANY SNOW FROM THIS SECOND SYSTEM WILL REMAIN WELL TO THE WEST OF SDF.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....ADL
AVIATION.....13
000
FXUS63 KLMK 182002
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
302 PM EST SUN JAN 18 2009
.SHORT TERM (TONIGHT AND MONDAY)...
LARGE SCALE H5 TROF CONTINUES TO BE SITUATED ACROSS THE EASTERN
U.S. SERIES OF VORTICITY LOBES CONTINUE TO ROTATE THROUGH WITHIN
THE MEAN FLOW. ONE OF THESE IS CURRENTLY MOVING THROUGH THE EASTERN
HALF OF THE REGION BRINGING A PERIOD OF LIGHT SNOW TO THE REGION.
WITH TEMPERATURES UP NEAR OR JUST ABOVE FREEZING...ACCUMULATIONS
HAVE BEEN GENERALLY NIL WITH A DUSTING HERE AND THERE. THIS SNOW
SHOWER ACTIVITY WILL CONTINUE TO PRESS SOUTHEAST INTO EASTERN KY
THIS AFTERNOON AND EVENING. AS THIS MOVES OUT...WE`LL BE IN A LULL
FOR A WHILE UNTIL THE NEXT VORT COMES DOWN LATER TONIGHT. IN
FACT...WOULD NOT BE SURPRISED TO SEE SOME BREAKS IN THE OVERCAST FOR
A TIME THIS AFTERNOON AND EVENING.
CURRENT WATER VAPOR IMAGERY SHOWING OUR VORT LOBE OF NOTE NOW
LOCATED UP ACROSS WISCONSIN AND MOVING QUICKLY TO THE SOUTH. ALL OF
THE SHORT TERM MODEL SOLUTIONS BRING THIS LOBE SOUTH INTO WEST KY
AND THEN A SHARP TURN TO THE EAST AS THE LOBE GOES INTO THE BASE OF
THE UPPER TROUGH. CURRENTLY...THIS LOBE IS PRODUCING A DECENT
AMOUNT OF SNOW ACROSS WISCONSIN AND EXPECT PRECIPITATION SHIELD TO
BE A GOOD SIZE AS IT MOVES THROUGH TONIGHT. WILL BE RAISING POPS
SIGNIFICANTLY AS EXPECT SNOW SHOWER COVERAGE TO BE QUITE LARGE. AS
THIS SYSTEM CROSSES INTO OUR REGION...SOME LOCAL ENHANCEMENT DUE TO
TOPOGRAPHIC EFFECTS ARE POSSIBLE. WITH THAT SAID...ACTUAL BEST
SNOWFALL ACCUMULATION POTENTIAL WILL BE ACROSS THE SOUTH...MAINLY
SOUTH OF THE WESTERN KY AND BLUEGRASS PARKWAYS. IN THAT
AREA...AROUND ONE INCH OF ACCUMULATION LOOKS LIKELY. THOUGH SOME
AREA MAY SEE LOCALIZED HIGHER AMOUNTS. NORTH OF THE
PARKWAYS...BETWEEN A HALF AND ONE INCH LOOKS LIKELY.
AFTER COORDINATING WITH SURROUNDING OFFICES...WE`LL BE HOLDING OFF
ON AN ADVISORY AT THIS TIME...AS BEST ACCUMULATIONS LOOK TO BE JUST
TO OUR SOUTHEAST...WHERE MORE TOPOGRAPHIC LIFT WILL ENHANCE THE
SNOWFALL ACTIVITY. HOWEVER...WE WILL CONTINUE TO WATCH UPSTREAM
OBSERVATIONS AND SNOWFALL AMOUNTS AND IF THE SYSTEM APPEARS STRONGER
THAN FORECAST AN ADVISORY MAY BE REQUIRED LATER THIS EVENING. IN
THE MEANTIME...WE WILL ISSUE A SPECIAL WEATHER STATEMENT
HIGHLIGHTING THE WINTER WEATHER POTENTIAL.
AS THIS SNOWBAND PUSHES SOUTHEAST OVERNIGHT...MUCH COLDER AIR WILL
PUSH IN BEHIND THE SYSTEM. OVERNIGHT LOWS WILL DROP INTO THE MID
AND UPPER TEENS ACROSS THE NORTH WITH LOWER 20S ACROSS THE FAR SOUTH.
FOR MONDAY...AS VORT LOBE PUSHES OFF TO THE EAST AS IT ROUNDS THE
BASE OF THE UPPER TROF...SOME SNOW SHOWERS WILL CONTINUE TO BE
POSSIBLE DURING THE MORNING HOURS...ESPECIALLY ACROSS THE EASTERN
SECTIONS. MOISTURE LOOKS TO DEPART QUICKLY...BUT NORTHWEST FLOW AND
STEEP LAPSE RATES SHOULD PROMOTE SCATTERED FLURRIES THROUGH THE
REMAINDER OF THE AFTERNOON. TEMPERATURES WILL BE TRICKY DEPENDING
ON SNOW ACCUMULATIONS. GIVEN THAT WE`RE EXPECTING SOME LIGHT
ACCUMULATIONS...WILL BE TRIMMING TEMPS UNDER GUIDANCE WITH HIGHS IN
THE MID TO UPPER 20S.
.LONG TERM (MONDAY NIGHT THROUGH SUNDAY)...
TROUGHING OVER THE ERN HALF OF THE CONUS WILL CONTINUE TO AFFECT US
FOR MOST OF THIS PERIOD. AN UPPER LEVEL DISTURBANCE ON THE BACK SIDE
OF THE MAIN TROUGH WILL ROTATE DOWN MONDAY NIGHT AND SHOULD PRODUCE
LIGHT SNOW SHOWERS ACROSS THE AREA. AGAIN THIS LOOKS LIKE A HIGH CHC
LOW QPF SITUATION...SO AT THIS POINT WILL CONTINUE THE 30-40 PERCENT
POPS...WITH THE BEST CHANCE OVER THE E/SE CWA MON NIGHT - TUES. WITH
THE GROUNDS BEING COLD ENOUGH...MAY ACTUALLY GET LIGHT ACCUMS OVER
THE ERN/SRN CWA. BEST CHANCE IS OVER THE SRN BLUEGRASS...HAVE LESS
THAN HALF AN INCH IN THE GRIDS THROUGH TUESDAY. BECAUSE OF
THIS...WENT A BIT BELOW MOS GUIDANCE OVER THE EAST...WITH TEENS FOR
LOW MON AND TUES NIGHTS...AND HIGHS TUESDAY IN THE MID 20S NE TO
NEAR FREEZING SW. POPS SHOULD END OVER THE EAST BY TUESDAY NIGHT.
WEDNESDAY-THURSDAY NIGHT...
THE UPPER-LEVEL FLOW FLATTENS OUT DURING THIS PERIOD AS NORTHWEST
FLOW MOVES OFF TO THE EAST. TEMPS WILL MODERATE BACK TO NEAR 40 ON
WED AND THEN TO THE UPPER 40S TO LOW 50S THURSDAY AHEAD OF THE NEXT
SYSTEM. THIS PERIOD SHOULD BE DRY.
FRIDAY-SUNDAY...
FOR LATE NEXT WEEK INTO NEXT WEEKEND...WE LAY IN BETWEEN A LOW TO
THE NORTH AND ONE TO THE SOUTH...WITH A WEAK FRONT PASSING THROUGH
DURING THE DAY FRIDAY. THE LOW/INVERTED SFC TROUGH TO THE SOUTH WILL
POOL MOISTURE INTO OUR AREA...SO THINK THE BEST CHANCE OF PRECIP
WILL COME ON THE BACK SIDE OF THIS TROUGH IN THE FORM OF RAIN
FRIDAY...AND THEN SNOW FRIDAY NIGHT AS TEMPERATURES COOL DOWN ON THE
BACK SIDE. LIGHT SNOW SHOWERS MAY LAST OVER THE BLUEGRASS DURING THE
DAY ON SATURDAY...BUT AT THIS POINT LEFT POPS OUT OVER THE EAST
SINCE ENSEMBLES SHOW IT BEING DRY. AFTER THAT FOR SUNDAY...HIGH
PRESSURE MOVES IN AND CONDITIONS DRY OUT.
&&
.AVIATION (18Z TAFS)...
REGIONAL RADAR IMAGERY SHOWING A BAND OF VERY LIGHT SNOW OR FLURRIES
MOVING SOUTH ACROSS SOUTHERN INDIANA AND INTO PARTS OF CENTRAL
KENTUCKY. THIS ACTIVITY WILL CONTINUE TO MOVE SOUTHEAST THROUGH
AFTERNOON AND MAINLY IMPACT THE KLEX AND KSDF TERMINALS. BASED ON
UPSTREAM OBS...IT LOOKS LIKELY THAT WE`LL SEE MVFR CIGS AND VSBY
WITH THIS BAND OF SNOW. SOME DROPS DOWN INTO IFR ARE CERTAINLY
POSSIBLE...MAINLY IN THE VSBY CATEGORY. SOME LIGHT SNOWS ARE
POSSIBLE IN THE KBWG AREA...BUT THINK CONDITIONS DOWN THERE WILL BE
SLIGHTLY BETTER WITH GENERALLY VFR CONDITIONS PREVAILING...THOUGH
SOME SNOW SHOWERS THERE MAY DROP CIGS/VSBY TO MVFR BRIEFLY. PIREP
REPORTS FROM AROUND THE AREA SHOW THAT THE STRATUS CLOUD TOPS ARE
RUNNING AROUND 6000-7500 AGL WITH SOME LIGHT ICING IN THE CLOUDS.
SFC WINDS THROUGH THE AFTERNOON ARE EXPECTED TO BE WESTERLY AT
7-10KTS.
AFTER 00Z...SECONDARY VORTICITY MAXIMUM LOOKS TO DROP INTO THE
REGION FROM THE NORTHWEST. MUCH OF THE MODEL GUIDANCE SUGGESTS
LIGHT SNOWS DEVELOPING ACROSS THE REGION ONCE AGAIN. CURRENT
INDICATIONS ARE THAT CIGS SHOULD BE MVFR PREVAILING WITH OCCASIONAL
DIPS INTO IFR IN THE SNOW SHOWERS. SAME CAN BE SAID WITH VSBY...OUT
OF THE SNOW SHOWERS...PREVAILING WILL BE VFR BUT MVFR/IFR IN THE
SNOW SHOWERS. SFC WINDS WILL WESTERLY AT 7-10KTS AROUND 00Z BUT THEN
SHIFTING TO THE NW (330-340 DEG) AT 5-8KTS OVERNIGHT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...MJ
LONG TERM....ADL
AVIATION.....MJ
000
FXUS63 KLMK 181643
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1143 AM EST SUN JAN 18 2009
.MORNING UPDATE...
SFC ANALYSIS REVEALS MAIN FRONTAL BOUNDARY IN FAR EASTERN KENTUCKY.
SECONDARY TROUGH AXIS WAS NOTED ACROSS SOUTHERN INDIANA. ASSOCIATED
WITH THIS FEATURE IS A VERY SMALL VORT LOBE WHICH THE MODELS SWING
INTO THE STATE LATER IN THE EARLY AFTERNOON. REGIONAL RADAR SHOWING
LIGHT SNOW WITH THIS FEATURE NOW OVER SOUTHWEST INDIANA. LATEST
MODEL DATA SUGGESTS THIS AREA SHOULD EXPAND A BIT DURING THE
AFTERNOON. WITH THAT SAID WILL BE MAINTAINING GOOD CHANCE POPS (50%
COVERAGE) FOR THIS AFTERNOON. COOLING ALOFT IS HELPING COOL THE
COLUMN ENOUGH THAT PRECIPITATION SHOULD BE IN THE FORM OF SNOW
ACROSS THE ENTIRE REGION.
TEMPERATURE FORECAST IS A BIT MORE COMPLEX. TEMPERATURES WILL
LIKELY FALL INTO THE UPPER 20S THROUGH THE REMAINDER OF THE DAY
ACROSS SOUTHERN INDIANA AND IN THE NORTHERN HALF OF KY (NORTH OF THE
WK AND BLUEGRASS PARKWAYS). ON THE OTHER HAND...SOMEWHAT OF A
DIURNAL SWING UPWARD LOOKS REASONABLE ACROSS THE SOUTH. TEMPS DOWN
INT HE BOWING GREEN AREA OVER TOWARD SOMERSET SHOULD RISE SLIGHTLY
OVER THE NEXT FEW HOURS AND THEN FALL DURING THE AFTERNOON AS COLDER
AIR WORKS ITS WAY DOWNSTATE. THE LATEST 12Z NAM RAW GUIDANCE IS WAY
TOO WARM AS IT SEEMS TO BE MISSING THE UPSTREAM PRECIPITATION MOVING
OUR WAY. THE 06Z GFS RAW AND 12Z RUC RAW GUIDANCE SEEMS TO BE MORE
REALISTIC AND WILL TREND THE FCST TOWARD THEM.
UPDATED FCST AND PRODUCTS WILL BE OUT BY 1100 AM EST.
.SHORT TERM (TODAY AND TONIGHT)...
A FRONTAL BOUNDARY WAS SITTING ALONG THE OHIO RIVER THIS MORNING
AROUND 7Z. 715Z RADAR IMAGERY SHOWS VERY LIGHT REFLECTIVITY OVER
SOUTHERN INDIANA AND EXTREME NORTHERN INDIANA. EARLY REPORTS
INDICATED THIS WAS A FREEZING DRIZZLE OR MIST. REFLECTIVITIES HAVE
DECREASED SINCE THEN SO DOUBT THAT MUCH OF IT IS EVEN REACHING THE
GROUND NOW. EXPECT VERY LIGHT PRECIP WILL CONTINUE ESPECIALLY
OVER SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS THIS
MORNING. WILL MENTION PATCHY LIGHT FREEZING DRIZZLE AS WELL AS
LIGHT SNOW THIS MORNING SINCE AS AIR COLUMN SHOULD BE COOLING
ENOUGH TO ALLOW A FEW FLAKES TO MIX IN.
FOR THIS AFTERNOON...EXPECT TO SEE SOME SCT SNOW SHOWERS OR
FLURRIES IN NW FLOW...SOME IP OR FZDZ MAY MIX IN OVER SOUTHERN KY.
NOT A REAL BIG TRIGGER FOR PRECIP THIS AFTERNOON SO ONLY EXPECT
TRACE AMOUNTS. TEMPS WILL BE MOSTLY IN THE 30S TODAY. TEMPS LOOK
TO BE A CHALLENGE. THE ARCTIC FRONT IS BEING STUBBORN IN MOVING E
THIS MORNING ALLOWING FOR MUCH WARMER TEMPS THIS MORNING THAN
PREVIOUSLY THOUGHT. THINKING IS THAT COLDER AIR WILL EVENTUALLY MAKE
IT INTO THE FORECAST AREA (FA) THIS AFTERNOON. SO A LOT OF LOCATIONS
WILL SEE NEARLY STEADY TEMPS IN THE 30S TODAY WITH SOME LOCATIONS
ACROSS THE NORTHERN FA FALLING A BIT THIS AFTERNOON.
TONIGHT...A STRONGER WAVE WILL ARRIVE BRINGING SCT SNOW SHOWERS
ACROSS THE AREA. COULD SEE UP TO A HALF INCH IN SOME LOCATIONS
ALTHOUGH IT/S DIFFICULT TO PINPOINT EXACTLY WHERE WITH SCT NATURE
OF CONVECTION. LOWS WILL DROP INTO THE UPPER TEENS AND LOWER 20S.
.LONG TERM (MONDAY THROUGH SATURDAY)...
ALL MODELS ARE RAPIDLY DRYING OUT THE AREA BEHIND THE EXITING SYSTEM
ON MONDAY AHEAD OF A DIVING UPPER TROUGH THAT WILL MOVE SOUTH
THROUGH THE OHIO AND TENNESSEE RIVER VALLEYS MONDAY NIGHT AND
TUESDAY. THE MODELS GENERALLY AGREE ON TAKING THE VAST MAJORITY OF
ANY WAVE ENERGY WITH THE TROUGH WELL TO THE WEST AND SOUTH OF THE
CWA...BUT ARE CONTINUING TO INDICATE A VARIETY OF SOLUTIONS IN
EXACTLY HOW MUCH LIFT GETS INTO SOUTH CENTRAL INDIANA AND CENTRAL
KENTUCKY AS THE TROUGH AXIS MOVES THROUGH. THE NAM MODEL IS THE MOST
AGGRESSIVE...BRINGING A WIDESPREAD VERY LIGHT SNOW EVENT UNDER
PROLONGED DEEPER LIFT TO ALMOST THE ENTIRE CWA...WHILE THE GFS AND
EUROPEAN MODELS ARE MUCH DRIER WITH ONLY A PERIOD OF SCATTERED LIGHT
SNOW SPREADING ACROSS THE REGION DURING THIS TIME.
AM INCLINED TO LEAN MORE TOWARD THE GFS AND EUROPEAN SOLUTIONS AT
THIS TIME CONSIDERING THE SREF AS WELL AS A MAJORITY OF THE CANADIAN
ENSEMBLES ARE INDICATING SIMILAR SCATTERED ACTIVITY WITH THIS
TROUGH. HOWEVER...CONSIDERING THE INFLUENCE OF THE UPSLOPE FLOW IN
THE EASTERN ZONES WILL CONTINUE TO INDICATE HIGHER POSSIBILITIES IN
THE BLUEGRASS REGION...BUT TREND BACK SLIGHTLY ON QPF/SNOW AMOUNTS.
BEYOND TUESDAY...SOME LINGERING FLURRIES MAY CONTINUE INTO TUESDAY
NIGHT BUT DRY AIR WORKS IN QUICKLY FOR THE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT PERIOD AND MADE NO CHANGES TO THE PREVIOUS FORECAST
FOR THESE PERIODS.
PREVIOUS DISCUSSION FOR THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (18Z TAFS)...
REGIONAL RADAR IMAGERY SHOWING A BAND OF VERY LIGHT SNOW OR FLURRIES
MOVING SOUTH ACROSS SOUTHERN INDIANA AND INTO PARTS OF CENTRAL
KENTUCKY. THIS ACTIVITY WILL CONTINUE TO MOVE SOUTHEAST THROUGH
AFTERNOON AND MAINLY IMPACT THE KLEX AND KSDF TERMINALS. BASED ON
UPSTREAM OBS...IT LOOKS LIKELY THAT WE`LL SEE MVFR CIGS AND VSBY
WITH THIS BAND OF SNOW. SOME DROPS DOWN INTO IFR ARE CERTAINLY
POSSIBLE...MAINLY IN THE VSBY CATEGORY. SOME LIGHT SNOWS ARE
POSSIBLE IN THE KBWG AREA...BUT THINK CONDITIONS DOWN THERE WILL BE
SLIGHTLY BETTER WITH GENERALLY VFR CONDITIONS PREVAILING...THOUGH
SOME SNOW SHOWERS THERE MAY DROP CIGS/VSBY TO MVFR BRIEFLY. PIREP
REPORTS FROM AROUND THE AREA SHOW THAT THE STRATUS CLOUD TOPS ARE
RUNNING AROUND 6000-7500 AGL WITH SOME LIGHT ICING IN THE CLOUDS.
SFC WINDS THROUGH THE AFTERNOON ARE EXPECTED TO BE WESTERLY AT
7-10KTS.
AFTER 00Z...SECONDARY VORTICITY MAXIMUM LOOKS TO DROP INTO THE
REGION FROM THE NORTHWEST. MUCH OF THE MODEL GUIDANCE SUGGESTS
LIGHT SNOWS DEVELOPING ACROSS THE REGION ONCE AGAIN. CURRENT
INDICATIONS ARE THAT CIGS SHOULD BE MVFR PREVAILING WITH OCCASIONAL
DIPS INTO IFR IN THE SNOW SHOWERS. SAME CAN BE SAID WITH VSBY...OUT
OF THE SNOW SHOWERS...PREVAILING WILL BE VFR BUT MVFR/IFR IN THE
SNOW SHOWERS. SFC WINDS WILL WESTERLY AT 7-10KTS AROUND 00Z BUT THEN
SHIFTING TO THE NW (330-340 DEG) AT 5-8KTS OVERNIGHT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE.......MJ
SHORT TERM...AML
LONG TERM....MACZKO
AVIATION.....MJ
000
FXUS63 KLMK 181527
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1027 AM EST SUN JAN 18 2009
.MORNING UPDATE...
SFC ANALYSIS REVEALS MAIN FRONTAL BOUNDARY IN FAR EASTERN KENTUCKY.
SECONDARY TROUGH AXIS WAS NOTED ACROSS SOUTHERN INDIANA. ASSOCIATED
WITH THIS FEATURE IS A VERY SMALL VORT LOBE WHICH THE MODELS SWING
INTO THE STATE LATER IN THE EARLY AFTERNOON. REGIONAL RADAR SHOWING
LIGHT SNOW WITH THIS FEATURE NOW OVER SOUTHWEST INDIANA. LATEST
MODEL DATA SUGGESTS THIS AREA SHOULD EXPAND A BIT DURING THE
AFTERNOON. WITH THAT SAID WILL BE MAINTAINING GOOD CHANCE POPS (50%
COVERAGE) FOR THIS AFTERNOON. COOLING ALOFT IS HELPING COOL THE
COLUMN ENOUGH THAT PRECIPITATION SHOULD BE IN THE FORM OF SNOW
ACROSS THE ENTIRE REGION.
TEMPERATURE FORECAST IS A BIT MORE COMPLEX. TEMPERATURES WILL
LIKELY FALL INTO THE UPPER 20S THROUGH THE REMAINDER OF THE DAY
ACROSS SOUTHERN INDIANA AND IN THE NORTHERN HALF OF KY (NORTH OF THE
WK AND BLUEGRASS PARKWAYS). ON THE OTHER HAND...SOMEWHAT OF A
DIURNAL SWING UPWARD LOOKS REASONABLE ACROSS THE SOUTH. TEMPS DOWN
INT HE BOWING GREEN AREA OVER TOWARD SOMERSET SHOULD RISE SLIGHTLY
OVER THE NEXT FEW HOURS AND THEN FALL DURING THE AFTERNOON AS COLDER
AIR WORKS ITS WAY DOWNSTATE. THE LATEST 12Z NAM RAW GUIDANCE IS WAY
TOO WARM AS IT SEEMS TO BE MISSING THE UPSTREAM PRECIPITATION MOVING
OUR WAY. THE 06Z GFS RAW AND 12Z RUC RAW GUIDANCE SEEMS TO BE MORE
REALISTIC AND WILL TREND THE FCST TOWARD THEM.
UPDATED FCST AND PRODUCTS WILL BE OUT BY 1100 AM EST.
.SHORT TERM (TODAY AND TONIGHT)...
A FRONTAL BOUNDARY WAS SITTING ALONG THE OHIO RIVER THIS MORNING
AROUND 7Z. 715Z RADAR IMAGERY SHOWS VERY LIGHT REFLECTIVITY OVER
SOUTHERN INDIANA AND EXTREME NORTHERN INDIANA. EARLY REPORTS
INDICATED THIS WAS A FREEZING DRIZZLE OR MIST. REFLECTIVITIES HAVE
DECREASED SINCE THEN SO DOUBT THAT MUCH OF IT IS EVEN REACHING THE
GROUND NOW. EXPECT VERY LIGHT PRECIP WILL CONTINUE ESPECIALLY
OVER SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS THIS
MORNING. WILL MENTION PATCHY LIGHT FREEZING DRIZZLE AS WELL AS
LIGHT SNOW THIS MORNING SINCE AS AIR COLUMN SHOULD BE COOLING
ENOUGH TO ALLOW A FEW FLAKES TO MIX IN.
FOR THIS AFTERNOON...EXPECT TO SEE SOME SCT SNOW SHOWERS OR
FLURRIES IN NW FLOW...SOME IP OR FZDZ MAY MIX IN OVER SOUTHERN KY.
NOT A REAL BIG TRIGGER FOR PRECIP THIS AFTERNOON SO ONLY EXPECT
TRACE AMOUNTS. TEMPS WILL BE MOSTLY IN THE 30S TODAY. TEMPS LOOK
TO BE A CHALLENGE. THE ARCTIC FRONT IS BEING STUBBORN IN MOVING E
THIS MORNING ALLOWING FOR MUCH WARMER TEMPS THIS MORNING THAN
PREVIOUSLY THOUGHT. THINKING IS THAT COLDER AIR WILL EVENTUALLY MAKE
IT INTO THE FORECAST AREA (FA) THIS AFTERNOON. SO A LOT OF LOCATIONS
WILL SEE NEARLY STEADY TEMPS IN THE 30S TODAY WITH SOME LOCATIONS
ACROSS THE NORTHERN FA FALLING A BIT THIS AFTERNOON.
TONIGHT...A STRONGER WAVE WILL ARRIVE BRINGING SCT SNOW SHOWERS
ACROSS THE AREA. COULD SEE UP TO A HALF INCH IN SOME LOCATIONS
ALTHOUGH IT/S DIFFICULT TO PINPOINT EXACTLY WHERE WITH SCT NATURE
OF CONVECTION. LOWS WILL DROP INTO THE UPPER TEENS AND LOWER 20S.
.LONG TERM (MONDAY THROUGH SATURDAY)...
ALL MODELS ARE RAPIDLY DRYING OUT THE AREA BEHIND THE EXITING SYSTEM
ON MONDAY AHEAD OF A DIVING UPPER TROUGH THAT WILL MOVE SOUTH
THROUGH THE OHIO AND TENNESSEE RIVER VALLEYS MONDAY NIGHT AND
TUESDAY. THE MODELS GENERALLY AGREE ON TAKING THE VAST MAJORITY OF
ANY WAVE ENERGY WITH THE TROUGH WELL TO THE WEST AND SOUTH OF THE
CWA...BUT ARE CONTINUING TO INDICATE A VARIETY OF SOLUTIONS IN
EXACTLY HOW MUCH LIFT GETS INTO SOUTH CENTRAL INDIANA AND CENTRAL
KENTUCKY AS THE TROUGH AXIS MOVES THROUGH. THE NAM MODEL IS THE MOST
AGGRESSIVE...BRINGING A WIDESPREAD VERY LIGHT SNOW EVENT UNDER
PROLONGED DEEPER LIFT TO ALMOST THE ENTIRE CWA...WHILE THE GFS AND
EUROPEAN MODELS ARE MUCH DRIER WITH ONLY A PERIOD OF SCATTERED LIGHT
SNOW SPREADING ACROSS THE REGION DURING THIS TIME.
AM INCLINED TO LEAN MORE TOWARD THE GFS AND EUROPEAN SOLUTIONS AT
THIS TIME CONSIDERING THE SREF AS WELL AS A MAJORITY OF THE CANADIAN
ENSEMBLES ARE INDICATING SIMILAR SCATTERED ACTIVITY WITH THIS
TROUGH. HOWEVER...CONSIDERING THE INFLUENCE OF THE UPSLOPE FLOW IN
THE EASTERN ZONES WILL CONTINUE TO INDICATE HIGHER POSSIBILITIES IN
THE BLUEGRASS REGION...BUT TREND BACK SLIGHTLY ON QPF/SNOW AMOUNTS.
BEYOND TUESDAY...SOME LINGERING FLURRIES MAY CONTINUE INTO TUESDAY
NIGHT BUT DRY AIR WORKS IN QUICKLY FOR THE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT PERIOD AND MADE NO CHANGES TO THE PREVIOUS FORECAST
FOR THESE PERIODS.
PREVIOUS DISCUSSION FOR THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (12Z TAFS)...
TAF CONCERNS FOR THIS PACKAGE INCLUDE CIGS...VSBYS...AND FRZN
PRECIP. CURRENTLY HAVE SOME LIGHT FZDZ FALLING AT LEX WITH PERHAPS
A FEW SNOWFLAKES MIXING IN. THE SFC FRONT WITH THE CLIPPER SYSTEM
IS VERY NEAR THE LEX/BWG TERMINALS. THIS MEANS WINDS WILL BE
SHIFTING TOWARDS DUE WEST SOON...AND PRECIP WILL BE EXITING LEX
WITHIN THE NEXT HOUR OR SO. CURRENTLY CIGS AT BWG ARE VFR...SDF
MVFR...AND LEX IFR. EXPECT ALL TERMINAL CIGS TO GO TO MVFR WITHIN
THE NEXT 2 TO 3 HOURS AND STAY THAT WAY THROUGH THE REST OF THE TAF
PERIOD. LEX VSBYS SHOULD IMPROVE TO VFR SOON ALSO.
FOR THIS AFTERNOON...CANNOT RULE OUT A FLURRY ESPECIALLY AT SDF AND
LEX...BUT WILL LEAVE OUT OF TAFS SINCE CHANCES ARE SLIM FOR THEM TO
HIT A TERMINAL. THE NEXT GOOD CHANCE FOR LIGHT SN AT THE TERMINALS
WILL BE AFTER 0Z WITH AN UPPER LEVEL WAVE WHICH WILL BRING SCT SNOW
SHOWERS TO THE REGION. IN THESE SHOWERS...MVFR VSBYS AND LOW END
MVFR CIGS WILL BE LIKELY. WINDS WILL BE FROM THE WEST AROUND 10 TO
12 KTS THIS AFTERNOON SHIFTING TO THE NW TONIGHT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE.......MJ
SHORT TERM...AML
LONG TERM....MACZKO
AVIATION.....AML
000
FXUS63 KLMK 181108
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
608 AM EST SUN JAN 18 2009
.SHORT TERM (TODAY AND TONIGHT)...
A FRONTAL BOUNDARY WAS SITTING ALONG THE OHIO RIVER THIS MORNING
AROUND 7Z. 715Z RADAR IMAGERY SHOWS VERY LIGHT REFLECTIVITY OVER
SOUTHERN INDIANA AND EXTREME NORTHERN INDIANA. EARLY REPORTS
INDICATED THIS WAS A FREEZING DRIZZLE OR MIST. REFLECTIVITIES HAVE
DECREASED SINCE THEN SO DOUBT THAT MUCH OF IT IS EVEN REACHING THE
GROUND NOW. EXPECT VERY LIGHT PRECIP WILL CONTINUE ESPECIALLY
OVER SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS THIS
MORNING. WILL MENTION PATCHY LIGHT FREEZING DRIZZLE AS WELL AS
LIGHT SNOW THIS MORNING SINCE AS AIR COLUMN SHOULD BE COOLING
ENOUGH TO ALLOW A FEW FLAKES TO MIX IN.
FOR THIS AFTERNOON...EXPECT TO SEE SOME SCT SNOW SHOWERS OR
FLURRIES IN NW FLOW...SOME IP OR FZDZ MAY MIX IN OVER SOUTHERN KY.
NOT A REAL BIG TRIGGER FOR PRECIP THIS AFTERNOON SO ONLY EXPECT
TRACE AMOUNTS. TEMPS WILL BE MOSTLY IN THE 30S TODAY. TEMPS LOOK
TO BE A CHALLENGE. THE ARCTIC FRONT IS BEING STUBBORN IN MOVING E
THIS MORNING ALLOWING FOR MUCH WARMER TEMPS THIS MORNING THAN
PREVIOUSLY THOUGHT. THINKING IS THAT COLDER AIR WILL EVENTUALLY MAKE
IT INTO THE FORECAST AREA (FA) THIS AFTERNOON. SO A LOT OF LOCATIONS
WILL SEE NEARLY STEADY TEMPS IN THE 30S TODAY WITH SOME LOCATIONS
ACROSS THE NORTHERN FA FALLING A BIT THIS AFTERNOON.
TONIGHT...A STRONGER WAVE WILL ARRIVE BRINGING SCT SNOW SHOWERS
ACROSS THE AREA. COULD SEE UP TO A HALF INCH IN SOME LOCATIONS
ALTHOUGH IT/S DIFFICULT TO PINPOINT EXACTLY WHERE WITH SCT NATURE
OF CONVECTION. LOWS WILL DROP INTO THE UPPER TEENS AND LOWER 20S.
.LONG TERM (MONDAY THROUGH SATURDAY)...
ALL MODELS ARE RAPIDLY DRYING OUT THE AREA BEHIND THE EXITING SYSTEM
ON MONDAY AHEAD OF A DIVING UPPER TROUGH THAT WILL MOVE SOUTH
THROUGH THE OHIO AND TENNESSEE RIVER VALLEYS MONDAY NIGHT AND
TUESDAY. THE MODELS GENERALLY AGREE ON TAKING THE VAST MAJORITY OF
ANY WAVE ENERGY WITH THE TROUGH WELL TO THE WEST AND SOUTH OF THE
CWA...BUT ARE CONTINUING TO INDICATE A VARIETY OF SOLUTIONS IN
EXACTLY HOW MUCH LIFT GETS INTO SOUTH CENTRAL INDIANA AND CENTRAL
KENTUCKY AS THE TROUGH AXIS MOVES THROUGH. THE NAM MODEL IS THE MOST
AGGRESSIVE...BRINGING A WIDESPREAD VERY LIGHT SNOW EVENT UNDER
PROLONGED DEEPER LIFT TO ALMOST THE ENTIRE CWA...WHILE THE GFS AND
EUROPEAN MODELS ARE MUCH DRIER WITH ONLY A PERIOD OF SCATTERED LIGHT
SNOW SPREADING ACROSS THE REGION DURING THIS TIME.
AM INCLINED TO LEAN MORE TOWARD THE GFS AND EUROPEAN SOLUTIONS AT
THIS TIME CONSIDERING THE SREF AS WELL AS A MAJORITY OF THE CANADIAN
ENSEMBLES ARE INDICATING SIMILAR SCATTERED ACTIVITY WITH THIS
TROUGH. HOWEVER...CONSIDERING THE INFLUENCE OF THE UPSLOPE FLOW IN
THE EASTERN ZONES WILL CONTINUE TO INDICATE HIGHER POSSIBILITIES IN
THE BLUEGRASS REGION...BUT TREND BACK SLIGHTLY ON QPF/SNOW AMOUNTS.
BEYOND TUESDAY...SOME LINGERING FLURRIES MAY CONTINUE INTO TUESDAY
NIGHT BUT DRY AIR WORKS IN QUICKLY FOR THE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT PERIOD AND MADE NO CHANGES TO THE PREVIOUS FORECAST
FOR THESE PERIODS.
PREVIOUS DISCUSSION FOR THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (12Z TAFS)...
TAF CONCERNS FOR THIS PACKAGE INCLUDE CIGS...VSBYS...AND FRZN
PRECIP. CURRENTLY HAVE SOME LIGHT FZDZ FALLING AT LEX WITH PERHAPS
A FEW SNOWFLAKES MIXING IN. THE SFC FRONT WITH THE CLIPPER SYSTEM
IS VERY NEAR THE LEX/BWG TERMINALS. THIS MEANS WINDS WILL BE
SHIFTING TOWARDS DUE WEST SOON...AND PRECIP WILL BE EXITING LEX
WITHIN THE NEXT HOUR OR SO. CURRENTLY CIGS AT BWG ARE VFR...SDF
MVFR...AND LEX IFR. EXPECT ALL TERMINAL CIGS TO GO TO MVFR WITHIN
THE NEXT 2 TO 3 HOURS AND STAY THAT WAY THROUGH THE REST OF THE TAF
PERIOD. LEX VSBYS SHOULD IMPROVE TO VFR SOON ALSO.
FOR THIS AFTERNOON...CANNOT RULE OUT A FLURRY ESPECIALLY AT SDF AND
LEX...BUT WILL LEAVE OUT OF TAFS SINCE CHANCES ARE SLIM FOR THEM TO
HIT A TERMINAL. THE NEXT GOOD CHANCE FOR LIGHT SN AT THE TERMINALS
WILL BE AFTER 0Z WITH AN UPPER LEVEL WAVE WHICH WILL BRING SCT SNOW
SHOWERS TO THE REGION. IN THESE SHOWERS...MVFR VSBYS AND LOW END
MVFR CIGS WILL BE LIKELY. WINDS WILL BE FROM THE WEST AROUND 10 TO
12 KTS THIS AFTERNOON SHIFTING TO THE NW TONIGHT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...AML
LONG TERM....MACZKO/MJ
AVIATION.....AML
000
FXUS63 KLMK 180801
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
301 AM EST SUN JAN 18 2009
.SHORT TERM (TODAY AND TONIGHT)...
A FRONTAL BOUNDARY WAS SITTING ALONG THE OHIO RIVER THIS MORNING
AROUND 7Z. 715Z RADAR IMAGERY SHOWS VERY LIGHT REFLECTIVITY OVER
SOUTHERN INDIANA AND EXTREME NORTHERN INDIANA. EARLY REPORTS
INDICATED THIS WAS A FREEZING DRIZZLE OR MIST. REFLECTIVITIES HAVE
DECREASED SINCE THEN SO DOUBT THAT MUCH OF IT IS EVEN REACHING THE
GROUND NOW. EXPECT VERY LIGHT PRECIP WILL CONTINUE ESPECIALLY
OVER SOUTHERN INDIANA...NORTHERN KY...AND THE BLUEGRASS THIS
MORNING. WILL MENTION PATCHY LIGHT FREEZING DRIZZLE AS WELL AS
LIGHT SNOW THIS MORNING SINCE AS AIR COLUMN SHOULD BE COOLING
ENOUGH TO ALLOW A FEW FLAKES TO MIX IN.
FOR THIS AFTERNOON...EXPECT TO SEE SOME SCT SNOW SHOWERS OR
FLURRIES IN NW FLOW...SOME IP OR FZDZ MAY MIX IN OVER SOUTHERN KY.
NOT A REAL BIG TRIGGER FOR PRECIP THIS AFTERNOON SO ONLY EXPECT
TRACE AMOUNTS. TEMPS WILL BE MOSTLY IN THE 30S TODAY. TEMPS LOOK
TO BE A CHALLENGE. THE ARCTIC FRONT IS BEING STUBBORN IN MOVING E
THIS MORNING ALLOWING FOR MUCH WARMER TEMPS THIS MORNING THAN PREVIOUSLY
THOUGHT. THINKING IS THAT COLDER AIR WILL EVENTUALLY MAKE IT INTO
THE FORECAST AREA (FA) THIS AFTERNOON. SO A LOT OF LOCATIONS WILL
SEE NEARLY STEADY TEMPS IN THE 30S TODAY WITH SOME LOCATIONS
ACROSS THE NORTHERN FA FALLING A BIT THIS AFTERNOON.
TONIGHT...A STRONGER WAVE WILL ARRIVE BRINGING SCT SNOW SHOWERS
ACROSS THE AREA. COULD SEE UP TO A HALF INCH IN SOME LOCATIONS
ALTHOUGH IT/S DIFFICULT TO PINPOINT EXACTLY WHERE WITH SCT NATURE
OF CONVECTION. LOWS WILL DROP INTO THE UPPER TEENS AND LOWER 20S.
.LONG TERM (MONDAY THROUGH SATURDAY)...
ALL MODELS ARE RAPIDLY DRYING OUT THE AREA BEHIND THE EXITING SYSTEM
ON MONDAY AHEAD OF A DIVING UPPER TROUGH THAT WILL MOVE SOUTH
THROUGH THE OHIO AND TENNESSEE RIVER VALLEYS MONDAY NIGHT AND
TUESDAY. THE MODELS GENERALLY AGREE ON TAKING THE VAST MAJORITY OF
ANY WAVE ENERGY WITH THE TROUGH WELL TO THE WEST AND SOUTH OF THE
CWA...BUT ARE CONTINUING TO INDICATE A VARIETY OF SOLUTIONS IN
EXACTLY HOW MUCH LIFT GETS INTO SOUTH CENTRAL INDIANA AND CENTRAL
KENTUCKY AS THE TROUGH AXIS MOVES THROUGH. THE NAM MODEL IS THE MOST
AGGRESSIVE...BRINGING A WIDESPREAD VERY LIGHT SNOW EVENT UNDER
PROLONGED DEEPER LIFT TO ALMOST THE ENTIRE CWA...WHILE THE GFS AND
EUROPEAN MODELS ARE MUCH DRIER WITH ONLY A PERIOD OF SCATTERED LIGHT
SNOW SPREADING ACROSS THE REGION DURING THIS TIME.
AM INCLINED TO LEAN MORE TOWARD THE GFS AND EUROPEAN SOLUTIONS AT
THIS TIME CONSIDERING THE SREF AS WELL AS A MAJORITY OF THE CANADIAN
ENSEMBLES ARE INDICATING SIMILAR SCATTERED ACTIVITY WITH THIS
TROUGH. HOWEVER...CONSIDERING THE INFLUENCE OF THE UPSLOPE FLOW IN
THE EASTERN ZONES WILL CONTINUE TO INDICATE HIGHER POSSIBILITIES IN
THE BLUEGRASS REGION...BUT TREND BACK SLIGHTLY ON QPF/SNOW AMOUNTS.
BEYOND TUESDAY...SOME LINGERING FLURRIES MAY CONTINUE INTO TUESDAY
NIGHT BUT DRY AIR WORKS IN QUICKLY FOR THE TUESDAY NIGHT THROUGH
WEDNESDAY NIGHT PERIOD AND MADE NO CHANGES TO THE PREVIOUS FORECAST
FOR THESE PERIODS.
PREVIOUS DISCUSSION FOR THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (06Z TAFS)...
TAF CONCERNS FOR THIS PACKAGE INCLUDE CIGS AND FRZN PRECIP.
CURRENTLY HAVE SOME VERY LIGHT MIST FALLING OVER SOUTHERN INDIANA
AND MOVING SE TOWARD THE SDF AND LEX TERMINALS. THIS IS VERY LIGHT
PATCHY PRECIP AND WILL NOT CAUSE ANY VSBY PROBLEMS...HOWEVER SINCE
SFC TEMPS ARE SO COLD...UPPER 20S IN SPOTS...THE LIGHT PRECIP MAY
CAUSE A FEW SLICK SPOTS. COLUMN OF AIR SHOULD BE COLD ENOUGH TO
SUPPORT SOME LIGHT SNOW SHOWERS OR FLURRIES AFTER 9Z THROUGH THE
MORNING HOURS AT SDF AND LEX. AGAIN PRECIP WILL BE LIGHT WITH NO
VSBY RESTRICTIONS. TERMINAL CIGS ARE ALREADY HOVERING NEAR OR ARE
IN THE MVFR CATEGORY AND WILL STAY THERE THROUGH THE TAF PERIOD.
GUSTY WINDS WITH THE FRONTAL BOUNDARY MOVING THROUGH THE AREA WILL
PERSIST AT THE TAF SITES ESPECIALLY OVER THE NEXT HOUR OR TWO BEFORE
DYING DOWN SOMEWHAT.
FOR SUNDAY...MVFR CIGS WILL BE PROMINENT. CANNOT RULE OUT A FLURRY
DURING THE AFTERNOON ESPECIALLY AT SDF AND LEX...BUT WILL LEAVE OUT
OF TAFS SINCE CHANCES ARE SLIM. THE NEXT GOOD CHANCE FOR LIGHT SN
AT THE TERMINALS WILL BE AFTER 0Z. WINDS WILL BE FROM THE WEST
AROUND 10 TO 12 KTS SUNDAY AFTERNOON.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM...AML
LONG TERM....MACZKO/MJ
AVIATION.....AML
000
FXUS63 KLMK 180502 CCA
AFDLMK
AREA FORECAST DISCUSSION...CORR TO FCSTR SECTION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1202 AM EST SUN JAN 18 2009
.UPDATE...
FORECAST SOUNDINGS SHOWING ALMOST ALL AVAILABLE MOISTURE THIS
EVENING IN AREAS WITH TEMPERATURES WARMER THAN WHAT IS NECESSARY FOR
ICE CRYSTAL DEVELOPMENT SINCE THE MOISTURE BEARING CLOUD LAYER IS SO
SHALLOW. FAIRLY TYPICAL FREEZING DRIZZLE TYPES OF FORECAST
SOUNDINGS. TEMPERATURES TODAY ROSE ABOVE FREEZING AND ARE STILL IN
THE MIDDLE TO UPPER 30S. HOWEVER A CHECK OF PAVEMENT TEMPERATURES
SHOWS THAT MOST ROADWAYS STILL HAVE SURFACE TEMPERATURES IN THE 20S
TO LOWER 30S. A LOOK AT AREA OBSERVATIONS REVEALS FREEZING RAIN
(PROBABLY FREEZING DRIZZLE OR FREEZING SPRINKLES REALLY) OCCURRING
IN SOUTHEAST ILLINOIS...SOUTHWEST INDIANA...AND SOUTHEAST KENTUCKY.
A LOOK AT AREA RADARS SHOWS RETURNS BEGINNING TO DEVELOP ESPECIALLY
ACROSS EASTERN KENTUCKY AND CENTRAL INDIANA.
GIVEN ALL THIS...HAVE INSERTED SOME LIGHT FREEZING DRIZZLE INTO THE
FORECAST FOR SEVERAL HOURS TONIGHT. KEPT FREEZING PRECIP OUT OF THE
EXTREME WEST WHERE PAVEMENT AND AIR TEMPERATURES WERE WARMER.
ALSO...CHANGED PRECIPITATION TYPE OVER TO ALL SNOW AFTER THE COLD
FRONT PASSES TONIGHT BETWEEN 06Z AND 10Z. THE COLUMN LOOKS TO TURN
COLD ENOUGH TO SUPPORT ALL SNOW BEHIND THE FRONT.
IT IS IMPORTANT TO NOTE THAT ANY PRECIPITATION TONIGHT...BE IT
FREEZING OR FROZEN...WILL BE VERY LIGHT. NO HEADLINES ARE PLANNED AT
THIS TIME. NEVERTHELESS...IT/S SOMETHING TO KEEP AN EYE ON AND A FEW
SLICK SPOTS COULD CROP UP ESPECIALLY ON BRIDGES AND OVERPASSES.
THANKS TO IND...JKL...AND WHAS FOR COLLABORATION.
.SHORT TERM (TONIGHT AND SUNDAY)...
A RELIEF TO THE FRIGID TEMPERATURES CAME TODAY AS CURRENT AFTERNOON
HIGH TEMPS ARE RANGING IN THE MID 30S GENERALLY. FOR THE REST OF
THIS AFTERNOON AND TONIGHT...SOUTHWEST WINDS WILL CONTINUE TO BE
GUSTY UP TO AROUND 30 MPH AHEAD OF AN APPROACHING CLIPPER SYSTEM.
CLOUDS WILL BE ON THE INCREASE TONIGHT...AND LIGHT SNOW SHOWERS
SHOULD BEGIN OVER THE NRN CWA ROUGHLY AROUND 10PM-MIDNIGHT...
SPREADING ESE WITH TIME. MOST OF THE ACTIVITY FROM THE CLIPPER WILL
AFFECT THE NERN HALF OF THE CWA...MAINLY NE OF A LINE FROM PAOLI IN
TO LIBERTY KY. AREAS ACROSS THE NRN BLUEGRASS REGION COULD SEE UP TO
A HALF INCH OF SNOW ACCUMULATION BY SUNDAY DAWN...ALTHOUGH OVERALL
MOST LOCATIONS WILL HAVE A DUSTING IF THAT. LOOKS LIKE A GOOD SHOT
AT SNOW...BUT SINCE MOISTURE IS LIMITED DO NOT WANT TO GET CARRIED
AWAY WITH POPS. SO WITH THE HIGH CHC/LITTLE ACCUMULATION SITUATION
OVERNIGHT...WILL GO WITH LOW CHC POPS OVER THE SW AND HIGH CHC OVER
THE NE. THE AMPLE CLOUD COVERAGE OVERNIGHT WILL HELP KEEP LOWS FROM
PLUMMETING TOO MUCH. LOWS SHOULD BE IN THE MID 20S TO AROUND 30. A
FEW READINGS IN THE LOW 20S WILL BE POSSIBLE AS WELL.
FOR SUNDAY...THE SFC TROUGH ASSOCIATED WITH THE CLIPPER WILL BE EAST
OF THE AREA BY SUNDAY MORNING SO MOST OF THE SNOW SHOWERS WILL HAVE
TAPERED OFF OR WILL BE VERY LIGHT FOR THE REST OF THE DAY. THE
BLUEGRASS REGION WILL HAVE THE BEST CHANCE AT SNOW ON SUNDAY...BUT
WILL KEEP CHANCES OF SNOW LESS THAN 40 POPS. LITTLE TO NO ACCUMS ARE
EXPECTED ON SUNDAY...EXCEPT FOR MAYBE AN ADDITIONAL TENTH OR TWO
OVER THE BLUEGRASS.
WENT BELOW MOS GUIDANCE FOR HIGHS ON SUNDAY. NGM MOS GUIDANCE NAILED
THE FRIGID TEMPS YESTERDAY...SO WILL TREND TOWARDS THAT FOR HIGHS
TOMORROW...WHICH MEANS UPPER 20S OVER THE NRN BLUEGRASS TO THE MID
TO MAYBE THE UPPER 30S OVER THE SOUTH.
.LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...
SUNDAY NIGHT THROUGH WEDNESDAY NIGHT...
ANOTHER ACTIVE WEATHER PERIOD HERE AS UPPER LEVEL TROF OVER THE EAST
BEGINS TO RE-DEVELOP...DEEPEN AND THEN DRIFT EASTWARD AS UPPER LEVEL
RIDGE TO THE WEST PUSHES FURTHER EAST. AS THE UPPER LEVEL TROUGH
DEEPENS...A QUICK MOVING DISTURBANCE WITHIN THE FLOW WILL CRUISE
THROUGH THE REGION BRINGING A QUICK SHOT OF SNOW TO THE REGION.
SFC COLD FRONT IS FCST TO BE WELL EAST OF KY BY SUNDAY NIGHT. BY
THEN WE`LL BE IN NORTHWEST FLOW ALOFT AND AT THE SURFACE. COLD AIR
WILL CONTINUE TO FILTER IN WHICH WILL KEEP LAPSE RATES RATHER
STEEP. IN THIS KIND OF SETUP...EXPECT SCATTERED SNOW SHOWERS ACROSS
THE REGION. WEAK VORT LOBE LOOKS TO DROP JUST WEST OF THE REGION
WHICH COULD ENHANCE THE SNOW SHOWER ACTIVITY ACROSS THE EAST AND
SOUTH. RECENT TRENDS IN THE MODELS SUGGEST A LITTLE LESS MOISTURE
TO WORK WITH. BUT...WITH COLD TEMPS...ONLY A LITTLE BIT OF QPF
COULD PRODUCE A FLUFFY SNOW. AS IT STANDS RIGHT NOW...IT APPEARS
THAT ACCUMULATIONS OF LESS THAN AN INCH LOOK LIKELY. SOME AREAS MAY
SEE MORE DEPENDING ON TOPOGRAPHICAL EFFECTS. LOWS SUNDAY NIGHT WILL
BE IN THE MID TEENS ACROSS THE NORTH AND IN THE 18-22 DEG RANGE
ACROSS THE FAR SOUTH.
FOR MONDAY...VORT LOBE LOOKS TO CONTINUE TO PASS THROUGH THE BASE OF
THE TROUGH. SOME SCATTERED LIGHT SNOWS MAY CONTINUE ACROSS THE FAR
EASTERN SECTIONS WHERE SOME TOPOGRAPHIC UPSLOPE SNOWS MAY OCCUR.
TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS TOPPING OUT IN THE MID TO
UPPER 20S. SHOULD WE GET SOME ACCUMULATING SNOWS SUNDAY
NIGHT...THESE TEMPS WILL LIKELY BE TOO WARM AND WILL NEED TO BE
ADJUSTED DOWNWARD SOME.
AS WE MOVE INTO MONDAY NIGHT...WILL BE WATCHING THE LAST IN A SERIES
OF CLIPPER SYSTEMS MOVE TOWARD THE REGION. THIS CLIPPER...UNLIKE
ALL OF THE OTHERS SINCE THE BEGINNING OF THE YEAR ACTUALLY HAS A
MORE FAVORABLE TRACK FOR SNOWS ACROSS THE REGION. VORT LOBE ALOFT
AND ASSOCIATED SFC LOW LOOK TO DROP SOUTH ALONG AND JUST EAST OF THE
MS RIVER AND DOWN INTO WESTERN KY. WITH THIS TRACK...BEST SNOWS
WILL OCCUR JUST EAST OF THE SFC LOW TRACK...MAINLY ACROSS CENTRAL
AND EASTERN KY. QPF TRENDS HAVE COME DOWN FROM THE PREVIOUS RUNS A
LITTLE BIT. STILL THINK A DECENT SHOT OF ACCUMULATION LOOKS
LIKELY. FOR NOW...PLAN ON GOING WITH AROUND 1 INCH OF
ACCUMULATION...BUT WILL NEED TO MONITOR FUTURE RUNS TO SEE IF MORE
OR LESS WILL BE POSSIBLE. HAVE STUCK CLOSE TO THE BIAS-CORRECTED
GFS RAW TEMPS WITH LOWS IN THE LOW-MID TEENS NORTH AND UPPER TEENS
TO AROUND 20 IN THE SOUTH.
FOR TUE-WED...WILL LIKELY SEE SOME LIGHT SNOW FLURRY ACTIVITY IN THE
WAKE OF DEPARTING CLIPPER SYSTEM TUESDAY MORNING. UPPER LEVEL
TROUGH AXIS THEN LOOKS TO SHIFT A BIT FURTHER EAST AS RISING H5
HEIGHTS ENCROACH FROM THE WEST. DRIER AIR WILL ALSO BE WORKING INTO
THE REGION LEADING TO A DRY...BUT COLD PERIOD OF WEATHER.
TEMPERATURES ARE GOING TO BE TOUGH TO NAIL DOWN SINCE THEY WILL
DEPEND ON IF WE GET SOME SNOW COVER. AT THIS TIME...HAVE LOWERED
TEMPS SLIGHTLY FOR TUE WITH HIGHS IN THE UPPER 20S WITH SOME HIGHS
AROUND 30 ACROSS THE FAR SOUTH. AGAIN...IF WE GET SNOW...THESE MAY
HAVE TO BE ADJUSTED DOWN. LOWS TUESDAY NIGHT WILL BE IN THE MID TO
UPPER TEENS IN THE EAST TO AROUND 20 IN THE SOUTHWEST. A VERY
SLIGHT MODERATION IN TEMPS IS EXPECTED FOR WEDNESDAY WITH HIGHS IN
THE UPPER 20S TO THE LOWER 30S IN THE NORTHERN HALF WITH LOWER TO
MID 30S IN THE SOUTHERN SECTIONS OF KY.
THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (06Z TAFS)...
TAF CONCERNS FOR THIS PACKAGE INCLUDE CIGS AND FRZN PRECIP.
CURRENTLY HAVE SOME VERY LIGHT MIST FALLING OVER SOUTHERN INDIANA
AND MOVING SE TOWARD THE SDF AND LEX TERMINALS. THIS IS VERY LIGHT
PATCHY PRECIP AND WILL NOT CAUSE ANY VSBY PROBLEMS...HOWEVER SINCE
SFC TEMPS ARE SO COLD...UPPER 20S IN SPOTS...THE LIGHT PRECIP MAY
CAUSE A FEW SLICK SPOTS. COLUMN OF AIR SHOULD BE COLD ENOUGH TO
SUPPORT SOME LIGHT SNOW SHOWERS OR FLURRIES AFTER 9Z THROUGH THE
MORNING HOURS AT SDF AND LEX. AGAIN PRECIP WILL BE LIGHT WITH NO
VSBY RESTRICTIONS. TERMINAL CIGS ARE ALREADY HOVERING NEAR OR ARE
IN THE MVFR CATEGORY AND WILL STAY THERE THROUGH THE TAF PERIOD.
GUSTY WINDS WITH THE FRONTAL BOUNDARY MOVING THROUGH THE AREA WILL
PERSIST AT THE TAF SITES ESPECIALLY OVER THE NEXT HOUR OR TWO BEFORE
DYING DOWN SOMEWHAT.
FOR SUNDAY...MVFR CIGS WILL BE PROMINENT. CANNOT RULE OUT A FLURRY
DURING THE AFTERNOON ESPECIALLY AT SDF AND LEX...BUT WILL LEAVE OUT
OF TAFS SINCE CHANCES ARE SLIM. THE NEXT GOOD CHANCE FOR LIGHT SN
AT THE TERMINALS WILL BE AFTER 0Z. WINDS WILL BE FROM THE WEST
AROUND 10 TO 12 KTS SUNDAY AFTERNOON.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
UPDATE...13
SHORT TERM...AL
LONG TERM....MJ
AVIATION.....AML
000
FXUS63 KLMK 180217 CCA
AFDLMK
AREA FORECAST DISCUSSION...CORR TO FCSTR SECTION
NATIONAL WEATHER SERVICE LOUISVILLE KY
916 PM EST SAT JAN 17 2009
.UPDATE...
FORECAST SOUNDINGS SHOWING ALMOST ALL AVAILABLE MOISTURE THIS
EVENING IN AREAS WITH TEMPERATURES WARMER THAN WHAT IS NECESSARY FOR
ICE CRYSTAL DEVELOPMENT SINCE THE MOISTURE BEARING CLOUD LAYER IS SO
SHALLOW. FAIRLY TYPICAL FREEZING DRIZZLE TYPES OF FORECAST
SOUNDINGS. TEMPERATURES TODAY ROSE ABOVE FREEZING AND ARE STILL IN
THE MIDDLE TO UPPER 30S. HOWEVER A CHECK OF PAVEMENT TEMPERATURES
SHOWS THAT MOST ROADWAYS STILL HAVE SURFACE TEMPERATURES IN THE 20S
TO LOWER 30S. A LOOK AT AREA OBSERVATIONS REVEALS FREEZING RAIN
(PROBABLY FREEZING DRIZZLE OR FREEZING SPRINKLES REALLY) OCCURRING
IN SOUTHEAST ILLINOIS...SOUTHWEST INDIANA...AND SOUTHEAST KENTUCKY.
A LOOK AT AREA RADARS SHOWS RETURNS BEGINNING TO DEVELOP ESPECIALLY
ACROSS EASTERN KENTUCKY AND CENTRAL INDIANA.
GIVEN ALL THIS...HAVE INSERTED SOME LIGHT FREEZING DRIZZLE INTO THE
FORECAST FOR SEVERAL HOURS TONIGHT. KEPT FREEZING PRECIP OUT OF THE
EXTREME WEST WHERE PAVEMENT AND AIR TEMPERATURES WERE WARMER.
ALSO...CHANGED PRECIPITATION TYPE OVER TO ALL SNOW AFTER THE COLD
FRONT PASSES TONIGHT BETWEEN 06Z AND 10Z. THE COLUMN LOOKS TO TURN
COLD ENOUGH TO SUPPORT ALL SNOW BEHIND THE FRONT.
IT IS IMPORTANT TO NOTE THAT ANY PRECIPITATION TONIGHT...BE IT
FREEZING OR FROZEN...WILL BE VERY LIGHT. NO HEADLINES ARE PLANNED AT
THIS TIME. NEVERTHELESS...IT/S SOMETHING TO KEEP AN EYE ON AND A FEW
SLICK SPOTS COULD CROP UP ESPECIALLY ON BRIDGES AND OVERPASSES.
THANKS TO IND...JKL...AND WHAS FOR COLLABORATION.
.SHORT TERM (TONIGHT AND SUNDAY)...
A RELIEF TO THE FRIGID TEMPERATURES CAME TODAY AS CURRENT AFTERNOON
HIGH TEMPS ARE RANGING IN THE MID 30S GENERALLY. FOR THE REST OF
THIS AFTERNOON AND TONIGHT...SOUTHWEST WINDS WILL CONTINUE TO BE
GUSTY UP TO AROUND 30 MPH AHEAD OF AN APPROACHING CLIPPER SYSTEM.
CLOUDS WILL BE ON THE INCREASE TONIGHT...AND LIGHT SNOW SHOWERS
SHOULD BEGIN OVER THE NRN CWA ROUGHLY AROUND 10PM-MIDNIGHT...
SPREADING ESE WITH TIME. MOST OF THE ACTIVITY FROM THE CLIPPER WILL
AFFECT THE NERN HALF OF THE CWA...MAINLY NE OF A LINE FROM PAOLI IN
TO LIBERTY KY. AREAS ACROSS THE NRN BLUEGRASS REGION COULD SEE UP TO
A HALF INCH OF SNOW ACCUMULATION BY SUNDAY DAWN...ALTHOUGH OVERALL
MOST LOCATIONS WILL HAVE A DUSTING IF THAT. LOOKS LIKE A GOOD SHOT
AT SNOW...BUT SINCE MOISTURE IS LIMITED DO NOT WANT TO GET CARRIED
AWAY WITH POPS. SO WITH THE HIGH CHC/LITTLE ACCUMULATION SITUATION
OVERNIGHT...WILL GO WITH LOW CHC POPS OVER THE SW AND HIGH CHC OVER
THE NE. THE AMPLE CLOUD COVERAGE OVERNIGHT WILL HELP KEEP LOWS FROM
PLUMMETING TOO MUCH. LOWS SHOULD BE IN THE MID 20S TO AROUND 30. A
FEW READINGS IN THE LOW 20S WILL BE POSSIBLE AS WELL.
FOR SUNDAY...THE SFC TROUGH ASSOCIATED WITH THE CLIPPER WILL BE EAST
OF THE AREA BY SUNDAY MORNING SO MOST OF THE SNOW SHOWERS WILL HAVE
TAPERED OFF OR WILL BE VERY LIGHT FOR THE REST OF THE DAY. THE
BLUEGRASS REGION WILL HAVE THE BEST CHANCE AT SNOW ON SUNDAY...BUT
WILL KEEP CHANCES OF SNOW LESS THAN 40 POPS. LITTLE TO NO ACCUMS ARE
EXPECTED ON SUNDAY...EXCEPT FOR MAYBE AN ADDITIONAL TENTH OR TWO
OVER THE BLUEGRASS.
WENT BELOW MOS GUIDANCE FOR HIGHS ON SUNDAY. NGM MOS GUIDANCE NAILED
THE FRIGID TEMPS YESTERDAY...SO WILL TREND TOWARDS THAT FOR HIGHS
TOMORROW...WHICH MEANS UPPER 20S OVER THE NRN BLUEGRASS TO THE MID
TO MAYBE THE UPPER 30S OVER THE SOUTH.
.LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...
SUNDAY NIGHT THROUGH WEDNESDAY NIGHT...
ANOTHER ACTIVE WEATHER PERIOD HERE AS UPPER LEVEL TROF OVER THE EAST
BEGINS TO RE-DEVELOP...DEEPEN AND THEN DRIFT EASTWARD AS UPPER LEVEL
RIDGE TO THE WEST PUSHES FURTHER EAST. AS THE UPPER LEVEL TROUGH
DEEPENS...A QUICK MOVING DISTURBANCE WITHIN THE FLOW WILL CRUISE
THROUGH THE REGION BRINGING A QUICK SHOT OF SNOW TO THE REGION.
SFC COLD FRONT IS FCST TO BE WELL EAST OF KY BY SUNDAY NIGHT. BY
THEN WE`LL BE IN NORTHWEST FLOW ALOFT AND AT THE SURFACE. COLD AIR
WILL CONTINUE TO FILTER IN WHICH WILL KEEP LAPSE RATES RATHER
STEEP. IN THIS KIND OF SETUP...EXPECT SCATTERED SNOW SHOWERS ACROSS
THE REGION. WEAK VORT LOBE LOOKS TO DROP JUST WEST OF THE REGION
WHICH COULD ENHANCE THE SNOW SHOWER ACTIVITY ACROSS THE EAST AND
SOUTH. RECENT TRENDS IN THE MODELS SUGGEST A LITTLE LESS MOISTURE
TO WORK WITH. BUT...WITH COLD TEMPS...ONLY A LITTLE BIT OF QPF
COULD PRODUCE A FLUFFY SNOW. AS IT STANDS RIGHT NOW...IT APPEARS
THAT ACCUMULATIONS OF LESS THAN AN INCH LOOK LIKELY. SOME AREAS MAY
SEE MORE DEPENDING ON TOPOGRAPHICAL EFFECTS. LOWS SUNDAY NIGHT WILL
BE IN THE MID TEENS ACROSS THE NORTH AND IN THE 18-22 DEG RANGE
ACROSS THE FAR SOUTH.
FOR MONDAY...VORT LOBE LOOKS TO CONTINUE TO PASS THROUGH THE BASE OF
THE TROUGH. SOME SCATTERED LIGHT SNOWS MAY CONTINUE ACROSS THE FAR
EASTERN SECTIONS WHERE SOME TOPOGRAPHIC UPSLOPE SNOWS MAY OCCUR.
TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS TOPPING OUT IN THE MID TO
UPPER 20S. SHOULD WE GET SOME ACCUMULATING SNOWS SUNDAY
NIGHT...THESE TEMPS WILL LIKELY BE TOO WARM AND WILL NEED TO BE
ADJUSTED DOWNWARD SOME.
AS WE MOVE INTO MONDAY NIGHT...WILL BE WATCHING THE LAST IN A SERIES
OF CLIPPER SYSTEMS MOVE TOWARD THE REGION. THIS CLIPPER...UNLIKE
ALL OF THE OTHERS SINCE THE BEGINNING OF THE YEAR ACTUALLY HAS A
MORE FAVORABLE TRACK FOR SNOWS ACROSS THE REGION. VORT LOBE ALOFT
AND ASSOCIATED SFC LOW LOOK TO DROP SOUTH ALONG AND JUST EAST OF THE
MS RIVER AND DOWN INTO WESTERN KY. WITH THIS TRACK...BEST SNOWS
WILL OCCUR JUST EAST OF THE SFC LOW TRACK...MAINLY ACROSS CENTRAL
AND EASTERN KY. QPF TRENDS HAVE COME DOWN FROM THE PREVIOUS RUNS A
LITTLE BIT. STILL THINK A DECENT SHOT OF ACCUMULATION LOOKS
LIKELY. FOR NOW...PLAN ON GOING WITH AROUND 1 INCH OF
ACCUMULATION...BUT WILL NEED TO MONITOR FUTURE RUNS TO SEE IF MORE
OR LESS WILL BE POSSIBLE. HAVE STUCK CLOSE TO THE BIAS-CORRECTED
GFS RAW TEMPS WITH LOWS IN THE LOW-MID TEENS NORTH AND UPPER TEENS
TO AROUND 20 IN THE SOUTH.
FOR TUE-WED...WILL LIKELY SEE SOME LIGHT SNOW FLURRY ACTIVITY IN THE
WAKE OF DEPARTING CLIPPER SYSTEM TUESDAY MORNING. UPPER LEVEL
TROUGH AXIS THEN LOOKS TO SHIFT A BIT FURTHER EAST AS RISING H5
HEIGHTS ENCROACH FROM THE WEST. DRIER AIR WILL ALSO BE WORKING INTO
THE REGION LEADING TO A DRY...BUT COLD PERIOD OF WEATHER.
TEMPERATURES ARE GOING TO BE TOUGH TO NAIL DOWN SINCE THEY WILL
DEPEND ON IF WE GET SOME SNOW COVER. AT THIS TIME...HAVE LOWERED
TEMPS SLIGHTLY FOR TUE WITH HIGHS IN THE UPPER 20S WITH SOME HIGHS
AROUND 30 ACROSS THE FAR SOUTH. AGAIN...IF WE GET SNOW...THESE MAY
HAVE TO BE ADJUSTED DOWN. LOWS TUESDAY NIGHT WILL BE IN THE MID TO
UPPER TEENS IN THE EAST TO AROUND 20 IN THE SOUTHWEST. A VERY
SLIGHT MODERATION IN TEMPS IS EXPECTED FOR WEDNESDAY WITH HIGHS IN
THE UPPER 20S TO THE LOWER 30S IN THE NORTHERN HALF WITH LOWER TO
MID 30S IN THE SOUTHERN SECTIONS OF KY.
THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (00Z TAFS)...
SEVERAL CHALLENGES THIS TAF PERIOD...WITH MVFR CIGS...VFR
VSBYS...LIGHTER WINDS...AND A FEW SNOWFLAKES.
MVFR CEILING HAS BEEN DEVELOPING RAPIDLY LATE THIS AFTERNOON OVER
THE TENNESSEE AND OHIO VALLEYS. THIS IS IN ACCORDANCE WITH MODEL
PREDICTIONS...AND HAS ALREADY BROUGHT AN MVFR CEILING TO BWG. THAT
MVFR CEILING WILL PERSIST THROUGH THE TAF PERIOD AND WILL AFFECT THE
OTHER TWO SITES AS WELL.
WINDS HAVE JUST BEGUN TO SLACK OFF A BIT AND GUSTS HAVE STARTED TO
LOWER...AND THIS TREND WILL CONTINUE THROUGH THE REST OF THE
FORECAST.
LOW PRESSURE MEANDERING SLOWLY ACROSS MICHIGAN WILL DRAG A WEAK COLD
FRONT ACROSS THE TAF SITES BETWEEN 06Z AND 10Z EARLY SUNDAY MORNING.
THIS WILL BRING A WIND SHIFT TO THE WEST AND WILL LOWER CEILINGS
BELOW 2000 FEET. LIGHT SNOW WILL HAVE A TOUGH TIME GETTING GOING
THIS EVENING THANKS TO VERY DRY AIR AT THE SURFACE BUT SOME
SCATTERED LIGHT SNOWFALL CAN BE EXPECTED LATE TONIGHT INTO EARLY
SUNDAY AFTERNOON. NO PREVAILING RESTRICTIONS TO VISIBILITY ARE
EXPECTED AT THIS TIME. THE MOISTURE WITH THIS SYSTEM IS DENSE BUT
QUITE SHALLOW. THE POOL OF MOISTURE THAT WILL BRING US OUR BEST
CHANCE OF SNOW EARLY SUNDAY IS CURRENTLY OVER THE EASTERN DAKOTAS
AND WESTERN MINNESOTA AND IS ONLY ABLE TO SUPPORT FLURRIES AND A FEW
POCKETS OF LIGHT SNOW.
WILL LET -SN DROP FROM THE TAFS AROUND 15Z THOUGH STRAY FLURRIES OR
SPRINKLES WILL BE POSSIBLE THROUGH THE DAY. WILL HOLD ONTO MVFR
CEILINGS IN CAA BEHIND THE DEPARTING FRONTAL SYSTEM.
AT SDF VERY LIGHT SNOW MAY RETURN SUNDAY EVENING AS A WEAKENING
SECONDARY LOW SLIDES SOUTHEAST OUT OF THE MID MISSISSIPPI VALLEY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
UPDATE...13
SHORT TERM...AL
LONG TERM....MJ
AVIATION.....13
000
FXUS63 KLMK 180216
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
916 PM EST SAT JAN 17 2009
.UPDATE...
FORECAST SOUNDINGS SHOWING ALMOST ALL AVAILABLE MOISTURE THIS
EVENING IN AREAS WITH TEMPERATURES WARMER THAN WHAT IS NECESSARY FOR
ICE CRYSTAL DEVELOPMENT SINCE THE MOISTURE BEARING CLOUD LAYER IS SO
SHALLOW. FAIRLY TYPICAL FREEZING DRIZZLE TYPES OF FORECAST
SOUNDINGS. TEMPERATURES TODAY ROSE ABOVE FREEZING AND ARE STILL IN
THE MIDDLE TO UPPER 30S. HOWEVER A CHECK OF PAVEMENT TEMPERATURES
SHOWS THAT MOST ROADWAYS STILL HAVE SURFACE TEMPERATURES IN THE 20S
TO LOWER 30S. A LOOK AT AREA OBSERVATIONS REVEALS FREEZING RAIN
(PROBABLY FREEZING DRIZZLE OR FREEZING SPRINKLES REALLY) OCCURRING
IN SOUTHEAST ILLINOIS...SOUTHWEST INDIANA...AND SOUTHEAST KENTUCKY.
A LOOK AT AREA RADARS SHOWS RETURNS BEGINNING TO DEVELOP ESPECIALLY
ACROSS EASTERN KENTUCKY AND CENTRAL INDIANA.
GIVEN ALL THIS...HAVE INSERTED SOME LIGHT FREEZING DRIZZLE INTO THE
FORECAST FOR SEVERAL HOURS TONIGHT. KEPT FREEZING PRECIP OUT OF THE
EXTREME WEST WHERE PAVEMENT AND AIR TEMPERATURES WERE WARMER.
ALSO...CHANGED PRECIPITATION TYPE OVER TO ALL SNOW AFTER THE COLD
FRONT PASSES TONIGHT BETWEEN 06Z AND 10Z. THE COLUMN LOOKS TO TURN
COLD ENOUGH TO SUPPORT ALL SNOW BEHIND THE FRONT.
IT IS IMPORTANT TO NOTE THAT ANY PRECIPITATION TONIGHT...BE IT
FREEZING OR FROZEN...WILL BE VERY LIGHT. NO HEADLINES ARE PLANNED AT
THIS TIME. NEVERTHELESS...IT/S SOMETHING TO KEEP AN EYE ON AND A FEW
SLICK SPOTS COULD CROP UP ESPECIALLY ON BRIDGES AND OVERPASSES.
THANKS TO IND...JKL...AND WHAS FOR COLLABORATION.
.SHORT TERM (TONIGHT AND SUNDAY)...
A RELIEF TO THE FRIGID TEMPERATURES CAME TODAY AS CURRENT AFTERNOON
HIGH TEMPS ARE RANGING IN THE MID 30S GENERALLY. FOR THE REST OF
THIS AFTERNOON AND TONIGHT...SOUTHWEST WINDS WILL CONTINUE TO BE
GUSTY UP TO AROUND 30 MPH AHEAD OF AN APPROACHING CLIPPER SYSTEM.
CLOUDS WILL BE ON THE INCREASE TONIGHT...AND LIGHT SNOW SHOWERS
SHOULD BEGIN OVER THE NRN CWA ROUGHLY AROUND 10PM-MIDNIGHT...
SPREADING ESE WITH TIME. MOST OF THE ACTIVITY FROM THE CLIPPER WILL
AFFECT THE NERN HALF OF THE CWA...MAINLY NE OF A LINE FROM PAOLI IN
TO LIBERTY KY. AREAS ACROSS THE NRN BLUEGRASS REGION COULD SEE UP TO
A HALF INCH OF SNOW ACCUMULATION BY SUNDAY DAWN...ALTHOUGH OVERALL
MOST LOCATIONS WILL HAVE A DUSTING IF THAT. LOOKS LIKE A GOOD SHOT
AT SNOW...BUT SINCE MOISTURE IS LIMITED DO NOT WANT TO GET CARRIED
AWAY WITH POPS. SO WITH THE HIGH CHC/LITTLE ACCUMULATION SITUATION
OVERNIGHT...WILL GO WITH LOW CHC POPS OVER THE SW AND HIGH CHC OVER
THE NE. THE AMPLE CLOUD COVERAGE OVERNIGHT WILL HELP KEEP LOWS FROM
PLUMMETING TOO MUCH. LOWS SHOULD BE IN THE MID 20S TO AROUND 30. A
FEW READINGS IN THE LOW 20S WILL BE POSSIBLE AS WELL.
FOR SUNDAY...THE SFC TROUGH ASSOCIATED WITH THE CLIPPER WILL BE EAST
OF THE AREA BY SUNDAY MORNING SO MOST OF THE SNOW SHOWERS WILL HAVE
TAPERED OFF OR WILL BE VERY LIGHT FOR THE REST OF THE DAY. THE
BLUEGRASS REGION WILL HAVE THE BEST CHANCE AT SNOW ON SUNDAY...BUT
WILL KEEP CHANCES OF SNOW LESS THAN 40 POPS. LITTLE TO NO ACCUMS ARE
EXPECTED ON SUNDAY...EXCEPT FOR MAYBE AN ADDITIONAL TENTH OR TWO
OVER THE BLUEGRASS.
WENT BELOW MOS GUIDANCE FOR HIGHS ON SUNDAY. NGM MOS GUIDANCE NAILED
THE FRIGID TEMPS YESTERDAY...SO WILL TREND TOWARDS THAT FOR HIGHS
TOMORROW...WHICH MEANS UPPER 20S OVER THE NRN BLUEGRASS TO THE MID
TO MAYBE THE UPPER 30S OVER THE SOUTH.
.LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...
SUNDAY NIGHT THROUGH WEDNESDAY NIGHT...
ANOTHER ACTIVE WEATHER PERIOD HERE AS UPPER LEVEL TROF OVER THE EAST
BEGINS TO RE-DEVELOP...DEEPEN AND THEN DRIFT EASTWARD AS UPPER LEVEL
RIDGE TO THE WEST PUSHES FURTHER EAST. AS THE UPPER LEVEL TROUGH
DEEPENS...A QUICK MOVING DISTURBANCE WITHIN THE FLOW WILL CRUISE
THROUGH THE REGION BRINGING A QUICK SHOT OF SNOW TO THE REGION.
SFC COLD FRONT IS FCST TO BE WELL EAST OF KY BY SUNDAY NIGHT. BY
THEN WE`LL BE IN NORTHWEST FLOW ALOFT AND AT THE SURFACE. COLD AIR
WILL CONTINUE TO FILTER IN WHICH WILL KEEP LAPSE RATES RATHER
STEEP. IN THIS KIND OF SETUP...EXPECT SCATTERED SNOW SHOWERS ACROSS
THE REGION. WEAK VORT LOBE LOOKS TO DROP JUST WEST OF THE REGION
WHICH COULD ENHANCE THE SNOW SHOWER ACTIVITY ACROSS THE EAST AND
SOUTH. RECENT TRENDS IN THE MODELS SUGGEST A LITTLE LESS MOISTURE
TO WORK WITH. BUT...WITH COLD TEMPS...ONLY A LITTLE BIT OF QPF
COULD PRODUCE A FLUFFY SNOW. AS IT STANDS RIGHT NOW...IT APPEARS
THAT ACCUMULATIONS OF LESS THAN AN INCH LOOK LIKELY. SOME AREAS MAY
SEE MORE DEPENDING ON TOPOGRAPHICAL EFFECTS. LOWS SUNDAY NIGHT WILL
BE IN THE MID TEENS ACROSS THE NORTH AND IN THE 18-22 DEG RANGE
ACROSS THE FAR SOUTH.
FOR MONDAY...VORT LOBE LOOKS TO CONTINUE TO PASS THROUGH THE BASE OF
THE TROUGH. SOME SCATTERED LIGHT SNOWS MAY CONTINUE ACROSS THE FAR
EASTERN SECTIONS WHERE SOME TOPOGRAPHIC UPSLOPE SNOWS MAY OCCUR.
TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS TOPPING OUT IN THE MID TO
UPPER 20S. SHOULD WE GET SOME ACCUMULATING SNOWS SUNDAY
NIGHT...THESE TEMPS WILL LIKELY BE TOO WARM AND WILL NEED TO BE
ADJUSTED DOWNWARD SOME.
AS WE MOVE INTO MONDAY NIGHT...WILL BE WATCHING THE LAST IN A SERIES
OF CLIPPER SYSTEMS MOVE TOWARD THE REGION. THIS CLIPPER...UNLIKE
ALL OF THE OTHERS SINCE THE BEGINNING OF THE YEAR ACTUALLY HAS A
MORE FAVORABLE TRACK FOR SNOWS ACROSS THE REGION. VORT LOBE ALOFT
AND ASSOCIATED SFC LOW LOOK TO DROP SOUTH ALONG AND JUST EAST OF THE
MS RIVER AND DOWN INTO WESTERN KY. WITH THIS TRACK...BEST SNOWS
WILL OCCUR JUST EAST OF THE SFC LOW TRACK...MAINLY ACROSS CENTRAL
AND EASTERN KY. QPF TRENDS HAVE COME DOWN FROM THE PREVIOUS RUNS A
LITTLE BIT. STILL THINK A DECENT SHOT OF ACCUMULATION LOOKS
LIKELY. FOR NOW...PLAN ON GOING WITH AROUND 1 INCH OF
ACCUMULATION...BUT WILL NEED TO MONITOR FUTURE RUNS TO SEE IF MORE
OR LESS WILL BE POSSIBLE. HAVE STUCK CLOSE TO THE BIAS-CORRECTED
GFS RAW TEMPS WITH LOWS IN THE LOW-MID TEENS NORTH AND UPPER TEENS
TO AROUND 20 IN THE SOUTH.
FOR TUE-WED...WILL LIKELY SEE SOME LIGHT SNOW FLURRY ACTIVITY IN THE
WAKE OF DEPARTING CLIPPER SYSTEM TUESDAY MORNING. UPPER LEVEL
TROUGH AXIS THEN LOOKS TO SHIFT A BIT FURTHER EAST AS RISING H5
HEIGHTS ENCROACH FROM THE WEST. DRIER AIR WILL ALSO BE WORKING INTO
THE REGION LEADING TO A DRY...BUT COLD PERIOD OF WEATHER.
TEMPERATURES ARE GOING TO BE TOUGH TO NAIL DOWN SINCE THEY WILL
DEPEND ON IF WE GET SOME SNOW COVER. AT THIS TIME...HAVE LOWERED
TEMPS SLIGHTLY FOR TUE WITH HIGHS IN THE UPPER 20S WITH SOME HIGHS
AROUND 30 ACROSS THE FAR SOUTH. AGAIN...IF WE GET SNOW...THESE MAY
HAVE TO BE ADJUSTED DOWN. LOWS TUESDAY NIGHT WILL BE IN THE MID TO
UPPER TEENS IN THE EAST TO AROUND 20 IN THE SOUTHWEST. A VERY
SLIGHT MODERATION IN TEMPS IS EXPECTED FOR WEDNESDAY WITH HIGHS IN
THE UPPER 20S TO THE LOWER 30S IN THE NORTHERN HALF WITH LOWER TO
MID 30S IN THE SOUTHERN SECTIONS OF KY.
THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (00Z TAFS)...
SEVERAL CHALLENGES THIS TAF PERIOD...WITH MVFR CIGS...VFR
VSBYS...LIGHTER WINDS...AND A FEW SNOWFLAKES.
MVFR CEILING HAS BEEN DEVELOPING RAPIDLY LATE THIS AFTERNOON OVER
THE TENNESSEE AND OHIO VALLEYS. THIS IS IN ACCORDANCE WITH MODEL
PREDICTIONS...AND HAS ALREADY BROUGHT AN MVFR CEILING TO BWG. THAT
MVFR CEILING WILL PERSIST THROUGH THE TAF PERIOD AND WILL AFFECT THE
OTHER TWO SITES AS WELL.
WINDS HAVE JUST BEGUN TO SLACK OFF A BIT AND GUSTS HAVE STARTED TO
LOWER...AND THIS TREND WILL CONTINUE THROUGH THE REST OF THE
FORECAST.
LOW PRESSURE MEANDERING SLOWLY ACROSS MICHIGAN WILL DRAG A WEAK COLD
FRONT ACROSS THE TAF SITES BETWEEN 06Z AND 10Z EARLY SUNDAY MORNING.
THIS WILL BRING A WIND SHIFT TO THE WEST AND WILL LOWER CEILINGS
BELOW 2000 FEET. LIGHT SNOW WILL HAVE A TOUGH TIME GETTING GOING
THIS EVENING THANKS TO VERY DRY AIR AT THE SURFACE BUT SOME
SCATTERED LIGHT SNOWFALL CAN BE EXPECTED LATE TONIGHT INTO EARLY
SUNDAY AFTERNOON. NO PREVAILING RESTRICTIONS TO VISIBILITY ARE
EXPECTED AT THIS TIME. THE MOISTURE WITH THIS SYSTEM IS DENSE BUT
QUITE SHALLOW. THE POOL OF MOISTURE THAT WILL BRING US OUR BEST
CHANCE OF SNOW EARLY SUNDAY IS CURRENTLY OVER THE EASTERN DAKOTAS
AND WESTERN MINNESOTA AND IS ONLY ABLE TO SUPPORT FLURRIES AND A FEW
POCKETS OF LIGHT SNOW.
WILL LET -SN DROP FROM THE TAFS AROUND 15Z THOUGH STRAY FLURRIES OR
SPRINKLES WILL BE POSSIBLE THROUGH THE DAY. WILL HOLD ONTO MVFR
CEILINGS IN CAA BEHIND THE DEPARTING FRONTAL SYSTEM.
AT SDF VERY LIGHT SNOW MAY RETURN SUNDAY EVENING AS A WEAKENING
SECONDARY LOW SLIDES SOUTHEAST OUT OF THE MID MISSISSIPPI VALLEY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...AL
LONG TERM....MJ
AVIATION.....13
000
FXUS63 KLMK 172324
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
623 PM EST SAT JAN 17 2009
.SHORT TERM (TONIGHT AND SUNDAY)...
A RELIEF TO THE FRIGID TEMPERATURES CAME TODAY AS CURRENT AFTERNOON
HIGH TEMPS ARE RANGING IN THE MID 30S GENERALLY. FOR THE REST OF
THIS AFTERNOON AND TONIGHT...SOUTHWEST WINDS WILL CONTINUE TO BE
GUSTY UP TO AROUND 30 MPH AHEAD OF AN APPROACHING CLIPPER SYSTEM.
CLOUDS WILL BE ON THE INCREASE TONIGHT...AND LIGHT SNOW SHOWERS
SHOULD BEGIN OVER THE NRN CWA ROUGHLY AROUND 10PM-MIDNIGHT...
SPREADING ESE WITH TIME. MOST OF THE ACTIVITY FROM THE CLIPPER WILL
AFFECT THE NERN HALF OF THE CWA...MAINLY NE OF A LINE FROM PAOLI IN
TO LIBERTY KY. AREAS ACROSS THE NRN BLUEGRASS REGION COULD SEE UP TO
A HALF INCH OF SNOW ACCUMULATION BY SUNDAY DAWN...ALTHOUGH OVERALL
MOST LOCATIONS WILL HAVE A DUSTING IF THAT. LOOKS LIKE A GOOD SHOT
AT SNOW...BUT SINCE MOISTURE IS LIMITED DO NOT WANT TO GET CARRIED
AWAY WITH POPS. SO WITH THE HIGH CHC/LITTLE ACCUMULATION SITUATION
OVERNIGHT...WILL GO WITH LOW CHC POPS OVER THE SW AND HIGH CHC OVER
THE NE. THE AMPLE CLOUD COVERAGE OVERNIGHT WILL HELP KEEP LOWS FROM
PLUMMETING TOO MUCH. LOWS SHOULD BE IN THE MID 20S TO AROUND 30. A
FEW READINGS IN THE LOW 20S WILL BE POSSIBLE AS WELL.
FOR SUNDAY...THE SFC TROUGH ASSOCIATED WITH THE CLIPPER WILL BE EAST
OF THE AREA BY SUNDAY MORNING SO MOST OF THE SNOW SHOWERS WILL HAVE
TAPERED OFF OR WILL BE VERY LIGHT FOR THE REST OF THE DAY. THE
BLUEGRASS REGION WILL HAVE THE BEST CHANCE AT SNOW ON SUNDAY...BUT
WILL KEEP CHANCES OF SNOW LESS THAN 40 POPS. LITTLE TO NO ACCUMS ARE
EXPECTED ON SUNDAY...EXCEPT FOR MAYBE AN ADDITIONAL TENTH OR TWO
OVER THE BLUEGRASS.
WENT BELOW MOS GUIDANCE FOR HIGHS ON SUNDAY. NGM MOS GUIDANCE NAILED
THE FRIGID TEMPS YESTERDAY...SO WILL TREND TOWARDS THAT FOR HIGHS
TOMORROW...WHICH MEANS UPPER 20S OVER THE NRN BLUEGRASS TO THE MID
TO MAYBE THE UPPER 30S OVER THE SOUTH.
.LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...
SUNDAY NIGHT THROUGH WEDNESDAY NIGHT...
ANOTHER ACTIVE WEATHER PERIOD HERE AS UPPER LEVEL TROF OVER THE EAST
BEGINS TO RE-DEVELOP...DEEPEN AND THEN DRIFT EASTWARD AS UPPER LEVEL
RIDGE TO THE WEST PUSHES FURTHER EAST. AS THE UPPER LEVEL TROUGH
DEEPENS...A QUICK MOVING DISTURBANCE WITHIN THE FLOW WILL CRUISE
THROUGH THE REGION BRINGING A QUICK SHOT OF SNOW TO THE REGION.
SFC COLD FRONT IS FCST TO BE WELL EAST OF KY BY SUNDAY NIGHT. BY
THEN WE`LL BE IN NORTHWEST FLOW ALOFT AND AT THE SURFACE. COLD AIR
WILL CONTINUE TO FILTER IN WHICH WILL KEEP LAPSE RATES RATHER
STEEP. IN THIS KIND OF SETUP...EXPECT SCATTERED SNOW SHOWERS ACROSS
THE REGION. WEAK VORT LOBE LOOKS TO DROP JUST WEST OF THE REGION
WHICH COULD ENHANCE THE SNOW SHOWER ACTIVITY ACROSS THE EAST AND
SOUTH. RECENT TRENDS IN THE MODELS SUGGEST A LITTLE LESS MOISTURE
TO WORK WITH. BUT...WITH COLD TEMPS...ONLY A LITTLE BIT OF QPF
COULD PRODUCE A FLUFFY SNOW. AS IT STANDS RIGHT NOW...IT APPEARS
THAT ACCUMULATIONS OF LESS THAN AN INCH LOOK LIKELY. SOME AREAS MAY
SEE MORE DEPENDING ON TOPOGRAPHICAL EFFECTS. LOWS SUNDAY NIGHT WILL
BE IN THE MID TEENS ACROSS THE NORTH AND IN THE 18-22 DEG RANGE
ACROSS THE FAR SOUTH.
FOR MONDAY...VORT LOBE LOOKS TO CONTINUE TO PASS THROUGH THE BASE OF
THE TROUGH. SOME SCATTERED LIGHT SNOWS MAY CONTINUE ACROSS THE FAR
EASTERN SECTIONS WHERE SOME TOPOGRAPHIC UPSLOPE SNOWS MAY OCCUR.
TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS TOPPING OUT IN THE MID TO
UPPER 20S. SHOULD WE GET SOME ACCUMULATING SNOWS SUNDAY
NIGHT...THESE TEMPS WILL LIKELY BE TOO WARM AND WILL NEED TO BE
ADJUSTED DOWNWARD SOME.
AS WE MOVE INTO MONDAY NIGHT...WILL BE WATCHING THE LAST IN A SERIES
OF CLIPPER SYSTEMS MOVE TOWARD THE REGION. THIS CLIPPER...UNLIKE
ALL OF THE OTHERS SINCE THE BEGINNING OF THE YEAR ACTUALLY HAS A
MORE FAVORABLE TRACK FOR SNOWS ACROSS THE REGION. VORT LOBE ALOFT
AND ASSOCIATED SFC LOW LOOK TO DROP SOUTH ALONG AND JUST EAST OF THE
MS RIVER AND DOWN INTO WESTERN KY. WITH THIS TRACK...BEST SNOWS
WILL OCCUR JUST EAST OF THE SFC LOW TRACK...MAINLY ACROSS CENTRAL
AND EASTERN KY. QPF TRENDS HAVE COME DOWN FROM THE PREVIOUS RUNS A
LITTLE BIT. STILL THINK A DECENT SHOT OF ACCUMULATION LOOKS
LIKELY. FOR NOW...PLAN ON GOING WITH AROUND 1 INCH OF
ACCUMULATION...BUT WILL NEED TO MONITOR FUTURE RUNS TO SEE IF MORE
OR LESS WILL BE POSSIBLE. HAVE STUCK CLOSE TO THE BIAS-CORRECTED
GFS RAW TEMPS WITH LOWS IN THE LOW-MID TEENS NORTH AND UPPER TEENS
TO AROUND 20 IN THE SOUTH.
FOR TUE-WED...WILL LIKELY SEE SOME LIGHT SNOW FLURRY ACTIVITY IN THE
WAKE OF DEPARTING CLIPPER SYSTEM TUESDAY MORNING. UPPER LEVEL
TROUGH AXIS THEN LOOKS TO SHIFT A BIT FURTHER EAST AS RISING H5
HEIGHTS ENCROACH FROM THE WEST. DRIER AIR WILL ALSO BE WORKING INTO
THE REGION LEADING TO A DRY...BUT COLD PERIOD OF WEATHER.
TEMPERATURES ARE GOING TO BE TOUGH TO NAIL DOWN SINCE THEY WILL
DEPEND ON IF WE GET SOME SNOW COVER. AT THIS TIME...HAVE LOWERED
TEMPS SLIGHTLY FOR TUE WITH HIGHS IN THE UPPER 20S WITH SOME HIGHS
AROUND 30 ACROSS THE FAR SOUTH. AGAIN...IF WE GET SNOW...THESE MAY
HAVE TO BE ADJUSTED DOWN. LOWS TUESDAY NIGHT WILL BE IN THE MID TO
UPPER TEENS IN THE EAST TO AROUND 20 IN THE SOUTHWEST. A VERY
SLIGHT MODERATION IN TEMPS IS EXPECTED FOR WEDNESDAY WITH HIGHS IN
THE UPPER 20S TO THE LOWER 30S IN THE NORTHERN HALF WITH LOWER TO
MID 30S IN THE SOUTHERN SECTIONS OF KY.
THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (00Z TAFS)...
SEVERAL CHALLENGES THIS TAF PERIOD...WITH MVFR CIGS...VFR
VSBYS...LIGHTER WINDS...AND A FEW SNOWFLAKES.
MVFR CEILING HAS BEEN DEVELOPING RAPIDLY LATE THIS AFTERNOON OVER
THE TENNESSEE AND OHIO VALLEYS. THIS IS IN ACCORDANCE WITH MODEL
PREDICTIONS...AND HAS ALREADY BROUGHT AN MVFR CEILING TO BWG. THAT
MVFR CEILING WILL PERSIST THROUGH THE TAF PERIOD AND WILL AFFECT THE
OTHER TWO SITES AS WELL.
WINDS HAVE JUST BEGUN TO SLACK OFF A BIT AND GUSTS HAVE STARTED TO
LOWER...AND THIS TREND WILL CONTINUE THROUGH THE REST OF THE
FORECAST.
LOW PRESSURE MEANDERING SLOWLY ACROSS MICHIGAN WILL DRAG A WEAK COLD
FRONT ACROSS THE TAF SITES BETWEEN 06Z AND 10Z EARLY SUNDAY MORNING.
THIS WILL BRING A WIND SHIFT TO THE WEST AND WILL LOWER CEILINGS
BELOW 2000 FEET. LIGHT SNOW WILL HAVE A TOUGH TIME GETTING GOING
THIS EVENING THANKS TO VERY DRY AIR AT THE SURFACE BUT SOME
SCATTERED LIGHT SNOWFALL CAN BE EXPECTED LATE TONIGHT INTO EARLY
SUNDAY AFTERNOON. NO PREVAILING RESTRICTIONS TO VISIBILITY ARE
EXPECTED AT THIS TIME. THE MOISTURE WITH THIS SYSTEM IS DENSE BUT
QUITE SHALLOW. THE POOL OF MOISTURE THAT WILL BRING US OUR BEST
CHANCE OF SNOW EARLY SUNDAY IS CURRENTLY OVER THE EASTERN DAKOTAS
AND WESTERN MINNESOTA AND IS ONLY ABLE TO SUPPORT FLURRIES AND A FEW
POCKETS OF LIGHT SNOW.
WILL LET -SN DROP FROM THE TAFS AROUND 15Z THOUGH STRAY FLURRIES OR
SPRINKLES WILL BE POSSIBLE THROUGH THE DAY. WILL HOLD ONTO MVFR
CEILINGS IN CAA BEHIND THE DEPARTING FRONTAL SYSTEM.
AT SDF VERY LIGHT SNOW MAY RETURN SUNDAY EVENING AS A WEAKENING
SECONDARY LOW SLIDES SOUTHEAST OUT OF THE MID MISSISSIPPI VALLEY.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...AL
LONG TERM....MJ
AVIATION.....13
000
FXUS63 KLMK 171946
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
246 PM EST SAT JAN 17 2009
.SHORT TERM (TONIGHT AND SUNDAY)...
A RELIEF TO THE FRIGID TEMPERATURES CAME TODAY AS CURRENT AFTERNOON
HIGH TEMPS ARE RANGING IN THE MID 30S GENERALLY. FOR THE REST OF
THIS AFTERNOON AND TONIGHT...SOUTHWEST WINDS WILL CONTINUE TO BE
GUSTY UP TO AROUND 30 MPH AHEAD OF AN APPROACHING CLIPPER SYSTEM.
CLOUDS WILL BE ON THE INCREASE TONIGHT...AND LIGHT SNOW SHOWERS
SHOULD BEGIN OVER THE NRN CWA ROUGHLY AROUND 10PM-MIDNIGHT...
SPREADING ESE WITH TIME. MOST OF THE ACTIVITY FROM THE CLIPPER WILL
AFFECT THE NERN HALF OF THE CWA...MAINLY NE OF A LINE FROM PAOLI IN
TO LIBERTY KY. AREAS ACROSS THE NRN BLUEGRASS REGION COULD SEE UP TO
A HALF INCH OF SNOW ACCUMULATION BY SUNDAY DAWN...ALTHOUGH OVERALL
MOST LOCATIONS WILL HAVE A DUSTING IF THAT. LOOKS LIKE A GOOD SHOT
AT SNOW...BUT SINCE MOISTURE IS LIMITED DO NOT WANT TO GET CARRIED
AWAY WITH POPS. SO WITH THE HIGH CHC/LITTLE ACCUMULATION SITUATION
OVERNIGHT...WILL GO WITH LOW CHC POPS OVER THE SW AND HIGH CHC OVER
THE NE. THE AMPLE CLOUD COVERAGE OVERNIGHT WILL HELP KEEP LOWS FROM
PLUMMETING TOO MUCH. LOWS SHOULD BE IN THE MID 20S TO AROUND 30. A
FEW READINGS IN THE LOW 20S WILL BE POSSIBLE AS WELL.
FOR SUNDAY...THE SFC TROUGH ASSOCIATED WITH THE CLIPPER WILL BE EAST
OF THE AREA BY SUNDAY MORNING SO MOST OF THE SNOW SHOWERS WILL HAVE
TAPERED OFF OR WILL BE VERY LIGHT FOR THE REST OF THE DAY. THE
BLUEGRASS REGION WILL HAVE THE BEST CHANCE AT SNOW ON SUNDAY...BUT
WILL KEEP CHANCES OF SNOW LESS THAN 40 POPS. LITTLE TO NO ACCUMS ARE
EXPECTED ON SUNDAY...EXCEPT FOR MAYBE AN ADDITIONAL TENTH OR TWO
OVER THE BLUEGRASS.
WENT BELOW MOS GUIDANCE FOR HIGHS ON SUNDAY. NGM MOS GUIDANCE NAILED
THE FRIGID TEMPS YESTERDAY...SO WILL TREND TOWARDS THAT FOR HIGHS
TOMORROW...WHICH MEANS UPPER 20S OVER THE NRN BLUEGRASS TO THE MID
TO MAYBE THE UPPER 30S OVER THE SOUTH.
.LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...
SUNDAY NIGHT THROUGH WEDNESDAY NIGHT...
ANOTHER ACTIVE WEATHER PERIOD HERE AS UPPER LEVEL TROF OVER THE EAST
BEGINS TO RE-DEVELOP...DEEPEN AND THEN DRIFT EASTWARD AS UPPER LEVEL
RIDGE TO THE WEST PUSHES FURTHER EAST. AS THE UPPER LEVEL TROUGH
DEEPENS...A QUICK MOVING DISTURBANCE WITHIN THE FLOW WILL CRUISE
THROUGH THE REGION BRINGING A QUICK SHOT OF SNOW TO THE REGION.
SFC COLD FRONT IS FCST TO BE WELL EAST OF KY BY SUNDAY NIGHT. BY
THEN WE`LL BE IN NORTHWEST FLOW ALOFT AND AT THE SURFACE. COLD AIR
WILL CONTINUE TO FILTER IN WHICH WILL KEEP LAPSE RATES RATHER
STEEP. IN THIS KIND OF SETUP...EXPECT SCATTERED SNOW SHOWERS ACROSS
THE REGION. WEAK VORT LOBE LOOKS TO DROP JUST WEST OF THE REGION
WHICH COULD ENHANCE THE SNOW SHOWER ACTIVITY ACROSS THE EAST AND
SOUTH. RECENT TRENDS IN THE MODELS SUGGEST A LITTLE LESS MOISTURE
TO WORK WITH. BUT...WITH COLD TEMPS...ONLY A LITTLE BIT OF QPF
COULD PRODUCE A FLUFFY SNOW. AS IT STANDS RIGHT NOW...IT APPEARS
THAT ACCUMULATIONS OF LESS THAN AN INCH LOOK LIKELY. SOME AREAS MAY
SEE MORE DEPENDING ON TOPOGRAPHICAL EFFECTS. LOWS SUNDAY NIGHT WILL
BE IN THE MID TEENS ACROSS THE NORTH AND IN THE 18-22 DEG RANGE
ACROSS THE FAR SOUTH.
FOR MONDAY...VORT LOBE LOOKS TO CONTINUE TO PASS THROUGH THE BASE OF
THE TROUGH. SOME SCATTERED LIGHT SNOWS MAY CONTINUE ACROSS THE FAR
EASTERN SECTIONS WHERE SOME TOPOGRAPHIC UPSLOPE SNOWS MAY OCCUR.
TEMPS WILL REMAIN BELOW NORMAL WITH HIGHS TOPPING OUT IN THE MID TO
UPPER 20S. SHOULD WE GET SOME ACCUMULATING SNOWS SUNDAY
NIGHT...THESE TEMPS WILL LIKELY BE TOO WARM AND WILL NEED TO BE
ADJUSTED DOWNWARD SOME.
AS WE MOVE INTO MONDAY NIGHT...WILL BE WATCHING THE LAST IN A SERIES
OF CLIPPER SYSTEMS MOVE TOWARD THE REGION. THIS CLIPPER...UNLIKE
ALL OF THE OTHERS SINCE THE BEGINNING OF THE YEAR ACTUALLY HAS A
MORE FAVORABLE TRACK FOR SNOWS ACROSS THE REGION. VORT LOBE ALOFT
AND ASSOCIATED SFC LOW LOOK TO DROP SOUTH ALONG AND JUST EAST OF THE
MS RIVER AND DOWN INTO WESTERN KY. WITH THIS TRACK...BEST SNOWS
WILL OCCUR JUST EAST OF THE SFC LOW TRACK...MAINLY ACROSS CENTRAL
AND EASTERN KY. QPF TRENDS HAVE COME DOWN FROM THE PREVIOUS RUNS A
LITTLE BIT. STILL THINK A DECENT SHOT OF ACCUMULATION LOOKS
LIKELY. FOR NOW...PLAN ON GOING WITH AROUND 1 INCH OF
ACCUMULATION...BUT WILL NEED TO MONITOR FUTURE RUNS TO SEE IF MORE
OR LESS WILL BE POSSIBLE. HAVE STUCK CLOSE TO THE BIAS-CORRECTED
GFS RAW TEMPS WITH LOWS IN THE LOW-MID TEENS NORTH AND UPPER TEENS
TO AROUND 20 IN THE SOUTH.
FOR TUE-WED...WILL LIKELY SEE SOME LIGHT SNOW FLURRY ACTIVITY IN THE
WAKE OF DEPARTING CLIPPER SYSTEM TUESDAY MORNING. UPPER LEVEL
TROUGH AXIS THEN LOOKS TO SHIFT A BIT FURTHER EAST AS RISING H5
HEIGHTS ENCROACH FROM THE WEST. DRIER AIR WILL ALSO BE WORKING INTO
THE REGION LEADING TO A DRY...BUT COLD PERIOD OF WEATHER.
TEMPERATURES ARE GOING TO BE TOUGH TO NAIL DOWN SINCE THEY WILL
DEPEND ON IF WE GET SOME SNOW COVER. AT THIS TIME...HAVE LOWERED
TEMPS SLIGHTLY FOR TUE WITH HIGHS IN THE UPPER 20S WITH SOME HIGHS
AROUND 30 ACROSS THE FAR SOUTH. AGAIN...IF WE GET SNOW...THESE MAY
HAVE TO BE ADJUSTED DOWN. LOWS TUESDAY NIGHT WILL BE IN THE MID TO
UPPER TEENS IN THE EAST TO AROUND 20 IN THE SOUTHWEST. A VERY
SLIGHT MODERATION IN TEMPS IS EXPECTED FOR WEDNESDAY WITH HIGHS IN
THE UPPER 20S TO THE LOWER 30S IN THE NORTHERN HALF WITH LOWER TO
MID 30S IN THE SOUTHERN SECTIONS OF KY.
THURSDAY THROUGH SATURDAY...
BY THURSDAY...SFC RIDGING WILL BE JUST TO OUR EAST AND H5 HEIGHTS
WILL BE RISING AS DEPARTING TROUGH HEADS EAST. UPPER LEVEL FLOW
LOOKS TO BECOME MORE WESTERLY WITH TIME THU INTO FRIDAY BEFORE
BECOMING SOUTHWESTERLY ONCE AGAIN. DRY WEATHER IS EXPECTED HERE
WITH TEMPERATURES MODERATING ONCE AGAIN. HAVE STAYED A BIT BELOW
GUIDANCE HERE SINCE I BELIEVE THAT THE WARM AIR ADVECTION IS BEING A
BIT OVERDONE. HIGHS THU SHOULD WARM INTO THE LOWER TO MID 40S IN
THE NORTH AND MID TO UPPER 40S ACROSS THE FAR SOUTH. TEMPS WILL NOT
BE AS COOL THU NIGHT AS READINGS LOOK TO DROP INTO THE UPPER 20S IN
MOST LOCATIONS.
BY LATE THU...NEXT WEATHER SYSTEM LOOKS TO BE COMING IN FROM THE
WEST. BOTH THE 12Z GFS AND EURO SOLUTIONS SHOW SFC LOW GOING
THROUGH THE GREAT LAKES WITH ATTENDANT COLD FRONT SWEEPING THROUGH
THE REGION. THERE ARE DIFFERENCES IN THE WAY THE 12Z GFS AND EURO
HANDLE THE SYSTEM. THE GFS IS QUITE A BIT MORE WET...WHILE THE EURO
SHEARS OFF THE NORTHERN PART OF THE SYSTEM AND THEN LETS SOUTHERN
PART SCRAPE BY AND THEN HEAD SOUTH OF OUR AREA. THE ENSEMBLES ARE
IN GENERAL AGREEMENT AND HAVE VERY LOW CHANCES OF PRECIP. GIVEN THE
RELATIVE UNCERTAINTY WILL BE LEAVING THE FCST DRY ATTM AND LEAN
CLOSER TO THE 12Z EURO. SHOULD FURTHER TRENDS INDICATE PRECIP
CHANCES...MAY HAVE TO BRING THOSE UP IN LATER FORECAST. HIGHS
FRIDAY LOOK TO BE IN THE MID 30S NORTH...UPPER 30S SOUTH WITH
OVERNIGHT LOWS FRIDAY NIGHT DROPPING INTO THE LOWER 20S NORTH AND
MID-UPPER 20S SOUTH. SFC HIGH PRESSURE LOOKS TO SPREAD INTO THE
REGION FOR SATURDAY YIELDING DRY CONDITIONS AND HIGHS IN THE MID TO
UPPER 30S.
&&
.AVIATION (18Z TAFS)...
A SMALL AREA OF MVFR BKN CIGS MAY AFFECT THE BWG/SDF/LEX TERMINALS
OVER THE NEXT COUPLE OF HOURS BEFORE CLEARING OUT. THE SUNNY SKIES
BEHIND THE CLOUDS WILL HELP SOUTHWEST WINDS GUST UP TO 25KTS OR SO.
MOSTLY SUNNY SKIES AND GUSTY SOUTHWEST WINDS WILL CONTINUE AHEAD OF
AN APPROACHING SFC TROUGH. ONCE THIS ARRIVES...SOMETIME AFTER
00Z...THIS SHOULD BRING MVFR CIGS TO ALL THREE TERMINALS (POSSIBLY
HIGH IFR TO SDF/LEX) BY 06Z WITH LIGHT SNOW POSSIBLE AT SDF AND LEX.
THERE MAY BE BRIEF MVFR VSBYS FROM THE SNOW ESPECIALLY AT
LEX...MAYBE AT SDF. THE BEST CHANCE FOR THIS WILL BE BETWEEN
06-12Z...WITH LIGHT SNOW MOVING OFF TO THE EAST AFTER THAT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
WEATHER.GOV/LOUISVILLE
SHORT TERM...AL
LONG TERM....MJ
AVIATION.....AL
| 
