864
FXUS63 KLMK 010845
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
345 AM EST SAT FEB 1 2025
KEY MESSAGES
* DRY AND UNSEASONABLY MILD CONDITIONS FOR THIS WEEKEND INTO EARLY
NEXT WEEK.
* POTENTIAL FOR STRONG TO SEVERE STORMS WEDNESDAY INTO THURSDAY.
ALL SEVERE HAZARDS ARE POSSIBLE; FORECAST CONFIDENCE IS STILL LOW
AT THIS TIME.
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 345 AM EST SAT FEB 1 2025
EARLY MORNING SURFACE ANALYSIS AND RADAR IMAGERY SHOW THE COLD FRONT
PUSHING SOUTHWARD ALONG THE WK/BG PARKWAYS. SOME PATCHY DRIZZLE IS
OCCURRING ALONG THE FRONTAL BOUNDARY AND SHOULD CONTINUE FOR THE
NEXT FEW HOURS. THE FRONT WILL CONTINUE TO WORK SOUTHWARD AND
EVENTUALLY CLEAR THE CWA LATER THIS MORNING. ACCOMPANYING THE FRONT
IS A BAND OF LOW STRATUS THAT COVERS MUCH OF THE REGION.
TEMPERATURES ACROSS THE REGION WERE IN THE LOW-MID 40S, BUT COLDER
AIR WILL WORK INTO THE REGION FROM THE NORTH AS COLD ADVECTION
SPILLS INTO THE AREA BEHIND THE FRONT. FOR THE REMAINDER OF THE
OVERNIGHT PERIOD, MOSTLY CLOUDY SKIES ARE EXPECTED WITH TEMPERATURES
EXPECTED TO DROP INTO THE MID-UPPER 30S ACROSS THE NORTH WITH LOWER
40S IN THE SOUTH.
FOR TODAY, THE AFOREMENTIONED FRONTAL BOUNDARY WILL CONTINUE TO PUSH
SOUTHWARD AND MID-LEVEL SUBSIDENCE WILL OVERSPREAD THE REGION. THIS
SHOULD ALLOW SKIES TO CLEAR OUT BY MID-LATE MORNING ACROSS THE
NORTH. SKIES ACROSS THE SOUTH WILL REMAIN MOSTLY CLOUDY FOR MUCH OF
THE DAY, BUT SOME PARTIAL CLEARING IS EXPECTED BY LATE AFTERNOON.
WINDS WILL BE OUT OF THE NORTH THIS MORNING BUT WILL SHIFT TO THE
NORTHEAST THROUGHOUT THE DAY. AS FOR TEMPERATURES, HIGHS WILL BE IN
THE LOW-MID 40S ACROSS SOUTHERN IN AND MUCH OF THE BLUEGRASS REGION.
ELSEWHERE, TEMPS WILL WILL GENERALLY WARM INTO THE UPPER 40S TO NEAR
50 ALONG THE KY/TN BORDER. PARTLY CLOUDY SKIES ARE EXPECTED FOR
TONIGHT WITH DRY CONDITIONS. LOWS WILL RANGE FROM THE MID 30S OVER
THE BLUEGRASS TO THE UPPER 30S/NEAR 40 ACROSS SOUTHERN KY.
LONG TERM /SUNDAY THROUGH FRIDAY/
ISSUED AT 345 AM EST SAT FEB 1 2025
SUNDAY THROUGH TUESDAY NIGHT...
AS WE HEAD FROM THE SECOND HALF OF THE WEEKEND INTO THE BEGINNING OF
NEXT WEEK, A ZONAL UPPER FLOW PATTERN WILL BE PRESENT ACROSS NORTH
AMERICA, AS A BLOCKING HIGH/REX BLOCK SETS UP OVER THE GULF OF
ALASKA AND THE PACIFIC NW. AS A RESULT, STRONG N-S BAROCLINITY IS
EXPECTED ACROSS THE OHIO VALLEY AND INTO THE MIDWEST THROUGH MUCH OF
THE PERIOD, WITH CONSIDERABLE SWINGS IN TEMPERATURES FROM DAY TO DAY
AND ELEVATED UNCERTAINTY IN THE TEMPERATURE FORECAST AS A SFC
FRONTAL BOUNDARY MEANDERS ACROSS THE REGION. WHILE THE EXACT
TEMPERATURE FORECAST REMAINS ONLY LOW-MEDIUM CONFIDENCE, THERE IS
HIGH CONFIDENCE IN ABOVE NORMAL TEMPERATURES. IF TEMPERATURES TREND
A FEW DEGREES MILDER, PARTICULARLY ON MONDAY AND WEDNESDAY, HIGHS
MAY APPROACH DAILY RECORD VALUES, WHICH ARE IN THE UPPER 60S AND
LOWER 70S.
ON SUNDAY, THE MAIN UNCERTAINTY IN THE FORECAST IS HOW QUICKLY LOW-
LEVEL CLOUDS AND MOISTURE CLEARS. AS THE ABOVE-MENTIONED FRONT
STARTS TO SINK INTO THE REGION, INCREASING SW FLOW SHOULD HELP TO
BRING ENOUGH LOW-LEVEL WARM ADVECTION TO SCOUR OUT THE MOISTURE,
THOUGH IT CAN BE QUITE STUBBORN THIS TIME OF YEAR. HAVE TRENDED THIS
FORECAST IS A LITTLE COOLER TO APPROACH THE CLOUDIER HRRR/NAM
SOLUTIONS, ESPECIALLY ALONG AND NORTH OF I-64. MODEL SOUNDINGS ALSO
SUGGEST THE POTENTIAL FOR PATCHY DRIZZLE AROUND SUNRISE SUNDAY
MORNING, ESPECIALLY ACROSS SOUTHERN IN.
ON MONDAY, UPPER HEIGHTS SHOULD INCREASE OVER THE REGION, WITH
SUBTLE RIDGING EXPECTED TO DEVELOP OVER THE OHIO VALLEY. THIS SHOULD
HELP TO KEEP MOST OF THE AREA ENTRENCHED WITHIN THE WARM AIR MASS.
MONDAY LOOKS LIKE THE PICK OF THE WEEK IN TERMS OF COMBINED WARM
TEMPERATURES AND MOSTLY SUNNY SKIES. MONDAY NIGHT INTO TUESDAY, THE
WEAK RIDGING SHOULD FLATTEN A BIT, ALLOWING THE SFC FRONT TO SINK
INTO THE REGION FROM THE NORTH. THIS WOULD BRING INCREASED CLOUD
COVER AND COOLER NORTH WINDS INTO PORTIONS THE AREA FOR TUESDAY,
WITH THE GREATEST REDUCTIONS IN TEMPERATURES CURRENTLY EXPECTED
ALONG AND NORTH OF I-64. A STRAY SHOWER IS ALSO POSSIBLE AS THE
FRONT SETTLES INTO THE REGION; HOWEVER, COVERAGE IS CURRENTLY
EXPECTED TO BE LOW ENOUGH TO KEEP A DRY FORECAST GOING.
WEDNESDAY AND THURSDAY...
A TRANSITION TO A MORE ACTIVE PERIOD OF WEATHER IS EXPECTED DURING
THE MIDDLE OF NEXT WEEK. AS THE BLOCKING PATTERN OVER THE GULF OF
ALASKA BEGINS TO BREAK DOWN, UPPER ENERGY SHOULD EJECT FROM THE
PACIFIC NW ALONG THE US/CANADA BORDER TOWARD THE GREAT LAKES
WEDNESDAY INTO WEDNESDAY NIGHT. THERE IS STILL CONSIDERABLE SPREAD
IN ENSEMBLE GUIDANCE WITH THE POSITIONING, SPEED, AND AMPLITUDE OF
THIS DISTURBANCE WHICH WILL IMPACT SENSIBLE WEATHER ACROSS KENTUCKY
AND INDIANA WEDNESDAY INTO THURSDAY.
RAIN SHOWERS SHOULD BEGIN TO DEVELOP ACROSS THE AREA EARLY WEDNESDAY
MORNING WITHIN THE WARM RETURN FLOW/ISENTROPIC LIFT REGIME, WITH
SHOWERS CONTINUING OFF AND ON THROUGH THE DAY ON WEDNESDAY. AS THE
UPPER SHORTWAVE MOVES CLOSER TO THE AREA WEDNESDAY EVENING INTO
WEDNESDAY NIGHT, LOW-LEVEL SW FLOW WILL INCREASE, WITH EPS/NAEFS
ENSEMBLE MEAN 850 MB FLOW EXCEEDING THE 90TH PERCENTILE OF MODEL
CLIMATOLOGY. THIS WILL FURTHER MOISTEN AND DESTABILIZE THE
ATMOSPHERE, WITH ENSEMBLE MEAN PWAT VALUES EXCEEDING THE 95TH
PERCENTILE OF CLIMATOLOGY WEDNESDAY NIGHT. ECMWF EXTREME FORECAST
INDEX VALUES FOR CAPE AND CAPE-SHEAR EXCEED 0.8 ACROSS THE OHIO
VALLEY WEDNESDAY NIGHT INTO THURSDAY, INDICATING HIGH CONFIDENCE IN
ANOMALOUSLY HIGH INSTABILITY AND SHEAR. AS WOULD BE EXPECTED, CSU
MACHINE LEARNING GUIDANCE AND CIPS SEVERE ANALOGS BOTH SHOW AN
ENHANCED SIGNAL FOR SEVERE WEATHER OVER THE REGION WEDNESDAY NIGHT
INTO THURSDAY MORNING, WITH MODEL SOUNDINGS SHOWING PROFILES THAT
WOULD BE SUPPORTIVE OF ALL SEVERE HAZARDS, INCLUDING SPIN-UP
TORNADOES. WITH THAT BEING SAID, THERE ARE PLENTY OF FAILURE MODES
STILL OUT THERE IN THE SYNOPTIC-SCALE GUIDANCE, INCLUDING THE 00Z
GFS DETERMINISTIC RUN, WHICH KEEPS MUCH OF THE AREA WITHIN THE COOL
SECTOR FOR MOST OF THE EVENT AND KEEPS INSTABILITY ELEVATED.
HOWEVER, THE POTENTIAL FOR SEVERE WEATHER WILL BE WORTH WATCHING
OVER THE NEXT FEW DAYS. THE FLOODING THREAT WILL ALSO NEED TO BE
MONITORED GIVEN CURRENT SATURATED GROUND AND ELEVATED FLOWS IN AREA
WATERWAYS.
LATE WEEK...
BEHIND THE WEDNESDAY NIGHT/THURSDAY SYSTEM, THE UPPER PATTERN IS
EXPECTED TO RETURN TO A QUASI-ZONAL STATE, WITH THE SURFACE COLD
FRONT PUSHING JUST TO THE SOUTH OF THE AREA. WHILE THIS SHOULD ALLOW
COOLER AIR TO FILTER INTO THE REGION, IT WILL PREVENT SIGNIFICANTLY
DRIER AIR FROM MAKING IT INTO THE OHIO VALLEY, AND UNSETTLED WEATHER
WOULD BE FAVORED TO CONTINUE INTO FRIDAY AND SATURDAY. WHILE THERE
WILL ALMOST CERTAINLY BE BREAKS IN PRECIPITATION, TIMING IN ANY
WAVES OF PRECIPITATION IS CURRENTLY LOW CONFIDENCE, AND BLENDED
GUIDANCE KEEPS AT LEAST A LOW CHANCE OF PRECIPITATION IN THROUGH
MUCH OF THE LATE WEEK PERIOD INTO THE FIRST HALF OF NEXT WEEKEND.
WHILE TEMPERATURES SHOULD BE CLOSER TO SEASONAL NORMS, NO
SIGNIFICANT COOL DOWN IS EXPECTED THROUGH THE FIRST HALF OF NEXT
WEEKEND.
AVIATION /06Z TAFS THROUGH 12Z SUNDAY/
ISSUED AT 1206 AM EST SAT FEB 1 2025
VFR CONDITIONS WILL BE SEEN VERY EARLY IN THIS TAF PERIOD. HOWEVER,
A COLD FRONT DROPPING INTO THE REGION FROM THE NORTH WILL SHIFT
WINDS FROM THE WEST-SOUTHWEST TO THE NORTHWEST AND USHER IN LOWER
CIGS. LOOK FOR CIGS TO DROP FROM VFR INTO THE MVFR AND THEN INTO
IFR OVERNIGHT. SOME PATCHY DRIZZLE WILL BE POSSIBLE HERE AND THERE,
BUT COVERAGE SEEMS LIMITED TO PRECLUDE A MENTION IN THE TAF. LATER
THIS MORNING, WINDS WILL SHIFT TO THE NORTH AND THEN THE NORTHEAST
WITH CLEARING SKIES EXPECTED BY LATE MORNING INTO THE AFTERNOON
HOURS.
LMK WATCHES/WARNINGS/ADVISORIES
KY...NONE.
IN...NONE.
SHORT TERM...MJ
LONG TERM....CSG
AVIATION.....MJ
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