144
FXUS63 KLMK 040720
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
320 AM EDT THU SEP 4 2025
KEY MESSAGES
* COLD FRONT WILL SLOWLY WORK THROUGH THE REGION TODAY BRINGING
ROUNDS OF SHOWERS AND THUNDERSTORMS. A FEW STORMS COULD BE RATHER
STRONG ACROSS SOUTHERN AND SOUTHEASTERN KENTUCKY.
* A SECOND COLD FRONT WILL PUSH THROUGH THE REGION LATE FRIDAY AND
SATURDAY. STRONG TO SEVERE STORMS WILL BE POSSIBLE ACROSS THE
REGION AS THIS FEATURE PUSHES THROUGH.
* COOLER AND DRIER AIR WILL RETURN TO THE REGION LATE SATURDAY AND
INTO SUNDAY. WITH PLEASANT WEATHER EXPECTED NEXT WEEK.
SHORT TERM /THROUGH TONIGHT/
ISSUED AT 319 AM EDT THU SEP 4 2025
SURFACE COLD FRONT REMAINS JUST NORTHWEST OF THE AREA THIS MORNING.
AHEAD OF THIS BOUNDARY, A LINE OF THUNDERSTORMS CONTINUES TO PUSH
EASTWARD ACROSS THE FORECAST AREA. THE ATMOSPHERE ACROSS THE REGION
IS MARGINALLY UNSTABLE WITH ABOUT 500-750 J/KG OF MLCAPE AND 20-25
KTS OF SHEAR. MOST MODEL SOUNDINGS SHOW AN INVERSION NEAR THE
SURFACE AND MESOANALYSIS SHOWS RATHER POOR LOW-MID LEVEL LAPSE
RATES. NONETHELESS, SLAB FORCING ALONG THE FRONT WILL COMPENSATE
FOR THE RATHER MARGINAL CONDITIONS TO KEEP SHOWERS AND STORMS GOING
THROUGH THE OVERNIGHT HOURS. WELCOME RAINFALL IS EXPECTED WITH THIS
ACTIVITY ALONG WITH WIND GUSTS OF 35-40 MPH AND FREQUENT LIGHTNING.
RAINFALL AMOUNTS OF 0.25-0.75 ARE EXPECTED, THOUGH WITH SOME
TRAINING OF CELLS ALONG/JUST SOUTH OF THE OHIO RIVER, LOCALIZED 1-2
INCH AMOUNTS COULD OCCUR THROUGH SUNRISE. SOUTHERN KY MAY NOT SEE
MUCH RAINFALL THROUGH SUNRISE, OTHER THAN SOME SCATTERED SHOWERS
DOWN IN THE LAKE CUMBERLAND REGION.
FOR THE DAYTIME HOURS, SURFACE COLD FRONT IS EXPECTED TO SLOWLY PUSH
SOUTHWARD ACROSS THE REGION. ONGOING CONVECTION IS EXPECTED AFTER
SUNRISE ACROSS MUCH OF NORTH-CENTRAL AND EAST-CENTRAL KENTUCKY.
ADDITIONAL CONVECTIVE DEVELOPMENT IS EXPECTED LATER IN THE MORNING
AND INTO THE AFTERNOON HOURS AS DAYTIME HEATING OCCURS RESULTING IN
SUBSEQUENT DESTABILIZATION. STRONGEST DESTABILIZATION LOOKS TO BE
ACROSS OUR SOUTHEASTERN SECTIONS AND OUR FAR EAST AREAS. GIVEN
MODEL PROFILES, CAN SEE A RISK OF A FEW STRONG/SEVERE STORMS ACROSS
OUR SOUTHEAST SECTIONS. THE MAIN SEVERE WEATHER HAZARD LOOKS TO BE
ISOLATED DAMAGING WIND GUSTS. LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE ALONG WITH SOME FREQUENT/INTENSE LIGHTNING WITH THE
STRONGEST STORMS. CURRENT DAY ONE MARGINAL RISK FROM SPC LOOKS WELL
PLACED AT THIS TIME.
THROUGHOUT THE DAY, DRIER AIR WILL WORK INTO THE REGION BEHIND THE
COLD FRONT. THIS WILL HELP SCOUR OUT LOW CLOUDS ACROSS SOUTHERN IN
AND FAR NORTHERN KY DURING THE AFTERNOON. THE COLD ADVECTION AND
LINGERING CLOUD COVER WILL LIKELY KEEP TEMPERATURES DOWN IN THE
UPPER 60S TO THE LOWER 70S ACROSS SOUTHERN IN AND ACROSS NORTH-
CENTRAL AND EAST-CENTRAL KY. FARTHER SOUTH, ACROSS SOUTHERN KY, MORE
SUNSHINE AND HEATING SHOULD LEAD TO AFTERNOON TEMPERATURES WARMING
INTO THE UPPER 70S AND LOWER 80S.
FOR TONIGHT, LOOK FOR SHOWERS AND STORMS TO DIMINISH AS THE FRONT
PUSHES FURTHER SOUTHEAST AND DRIER AIR AND CONTINUED COLD ADVECTION
WORK INTO THE REGION. OVERNIGHT LOWS WILL DROP INTO THE LOW-MID 50S
ACROSS SOUTHERN INDIANA AND PORTIONS OF NORTH-CENTRAL AND EAST-
CENTRAL KENTUCKY. SOME WARMER READINGS WILL BE FOUND ACROSS
SOUTHERN KY WHERE LOWS WILL RANGE FROM THE UPPER 50S TO THE LOWER
60S WITH SOME PATCHY VALLEY FOG DEVELOPING LATE.
LONG TERM /FRIDAY THROUGH WEDNESDAY/
ISSUED AT 319 AM EDT THU SEP 4 2025
FRIDAY THROUGH SUNDAY...
LARGE SCALE UPPER LEVEL LOW WILL REMAIN IN PLACE ACROSS ONTARIO
THROUGH THE PERIOD WITH A STRONG SHORTWAVE TROUGH AXIS ROTATING
AROUND IT ON FRIDAY. THIS FEATURE WILL PUSH INTO THE REGION LATE
FRIDAY DRIVING ANOTHER COLD FRONT INTO THE REGION BRINGING ANOTHER
ROUND OF SHOWERS AND THUNDERSTORMS TO THE REGION.
A ROBUST RETURN FLOW EVENT IS EXPECTED ON FRIDAY AS A BROAD
SOUTHWEST FLOW KICKS IN ACROSS THE REGION. STRONG DIURNAL HEATING
SHOULD ALLOW TEMPERATURES TO WARM INTO THE MID 80S ACROSS SOUTHERN
INDIANA AND FAR NORTHERN KENTUCKY. ACROSS CENTRAL AND SOUTHERN
KENTUCKY, AFTERNOON TEMPERATURES LOOK TO SPIKE INTO THE UPPER 80S TO
THE LOWER 90S. WITH THE BROAD SOUTHWEST FLOW, WE EXPECT AMPLE
MOISTURE TO RETURN TO THE REGION WITH DEWPOINTS IN THE MID 60S TO
REACH AS FAR NORTH AS SOUTHERN IN AND OH. GIVEN THE AFOREMENTIONED
TEMPS IN THE UPPER 80S/LOWER 90S, THAT WOULD YIELD ABOUT 2000-2500
J/KG OF MLCAPE IN THE AFTERNOON. MODEL SOUNDINGS SHOW INCREASING
SHEAR VALUES RETURNING TO THE REGION WITH 35-40KTS EXPECTED. THIS
SHOULD RESULT IN A FAVORABLE ENVIRONMENT FOR ORGANIZED CONVECTION.
CONVECTION IS EXPECTED TO DEVELOP DURING THE AFTERNOON AS LARGE
SCALE ASCENT SPREADS ACROSS THE REGION. THE COMBINATION OF HEIGHT
FALLS AND STRONGER DIFFERENTIAL VORTICITY ADVECTION WILL BE THE MAIN
FORCING REGIME HERE. GIVEN THE DEGREE OF INSTABILITY AND SHEAR
PRESENT, ORGANIZED SEVERE WEATHER APPEARS LIKELY IN THE AFTERNOON
AND EVENING. AFTER A QUICK ANALYSIS OF MODEL HODOGRAPH PROFILES, A
RISK OF DAMAGING WINDS, LARGE HAIL, AND ISOLATED TORNADOES WILL BE
POSSIBLE ACROSS THE REGION. THE INITIAL CONVECTION MAYBE
SUPERCELLULAR GIVEN THE LOW-LEVEL CURVATURE ON THE HODOGRAPHS.
HOWEVER, UPSCALE GROWTH INTO MORE LINEAR CONVECTION SEEMS LIKELY
WITH WIND DAMAGE BECOMING THE MAIN THREAT IN THE EVENING AND INTO
THE OVERNIGHT HOURS. A MARGINAL RISK OF SEVERE HAS BEEN POSTED BY
SPC. HOWEVER, I SUSPECT THAT IF CURRENT TRENDS IN THE CAMS CONTINUE
THAT A SLIGHT RISK MAY BE JUSTIFIED IN SUBSEQUENT OUTLOOKS.
SHOWERS AND THUNDERSTORMS WILL LIKELY CONTINUE INTO FRIDAY EVENING
AND EARLY SATURDAY MORNING UNTIL WE LOSE DAYTIME HEATING. LOWS
FRIDAY NIGHT WILL DIP BACK INTO THE LOW-MID 50S OVER SOUTHERN IN AND
NORTHERN KY, WITH UPPER 50S MAINLY OVER SOUTHERN KY.
SATURDAY LOOKS TO FEATURE A BIT OF CLOUD COVER AND LINGERING SHOWERS
IN THE MORNING. THE SLOW DEPARTURE OF THE FRONT CONTINUES IN THE
LATEST GUIDANCE. IF CLOUDS AND SHOWERS HANG ACROSS THE REGION,
HIGHS ON SATURDAY MAY STAY IN THE 60S. HOWEVER, IF WE DO BREAK OUT
INTO SOME SUN, LATE DAY RECOVERY OF TEMPS INTO THE LOWER 70S WILL BE
POSSIBLE.
CLEARING SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO FALL INTO THE LOW-
MID 40S FOR SATURDAY NIGHT. WE COULD BREAK A LOW TEMPERATURE RECORD
OVER AT LEXINGTON SUNDAY MORNING. DRY CONDITIONS ARE EXPECTED ON
SUNDAY WITH HIGHS IN THE MIDDLE 70S.
MONDAY THROUGH WEDNESDAY...
IN THE EXTENDED, UPPER LEVEL TROUGHING WILL BE SEEN ACROSS THE
EASTERN CONUS AT THE BEGINNING OF THE PERIOD. HOWEVER, THIS TROUGH
AXIS WILL LIFT OUT FAIRLY QUICKLY WITH A RATHER ZONAL FLOW ALOFT
DEVELOPING BY TUESDAY AND SOME RIDGING BUILDING INTO THE REGION FROM
THE WEST BY WEDNESDAY. OVERALL WEATHER PATTERN LOOKS TO BE TRANQUIL
HERE WITH DRY WEATHER EXPECTED.
LOWS MONDAY MORNING WILL START OFF IN THE LOWER-MID 40S, THOUGH A
FEW OF THE VALLEY LOCATIONS COULD SEE SOME UPPER 30S IN SPOTS. HIGHS
MONDAY LOOK TO WARM INTO THE MIDDLE 70S. LOWS MONDAY NIGHT SHOULD
BE A LITTLE MILDER WITH READINGS IN THE MID-UPPER 40S. TUESDAY
SHOULD FEATURE HIGHS IN THE UPPER 70S TO NEAR 80 WITH OVERNIGHT LOWS
IN THE LOW-MID 50S. HIGHS BY WEDNESDAY LOOK TO WARM INTO THE LOWER
80S IN MOST LOCATIONS.
AVIATION /00Z TAFS THROUGH 06Z FRIDAY/
ISSUED AT 1254 AM EDT THU SEP 4 2025
SURFACE COLD FRONT TO THE NORTHWEST WILL MOVE SOUTHEAST THIS
MORNING. BAND OF SHOWERS AND STORMS OUT FROM NEAR KHNB TO KEVV WILL
MOVE EASTWARD ACROSS SOUTHERN IN AND NORTH-CENTRAL KY THIS MORNING.
CURRENT TRACKING HAS THIS COMPLEX COMING INTO THE KSDF TERMINAL
AROUND 04/07Z. EXPECT SOUTHWEST WINDS AHEAD OF THE FRONT OF 8-10KTS
AND THEN WE'LL SEE SOME GUSTS OF 20-25KT...MAYBE 30KTS AS THE LINE
GOES THROUGH. ELSEWHERE, WILL BE CARRYING SOME VCTS OVER AT KLEX
FOR SOME SCATTERED CELLS THAT MAY POP UP AHEAD THE MAIN LINE. EXPECT
THIS TO ENTER THE KLEX TERMINAL LATER THIS MORNING, AFTER 04/09-10Z.
FOR KBWG, MOSTLY A QUIET NIGHT THOUGH SOME STORMS MAY APPROACH THE
TERMINAL IN THE 04/09-11Z TIME FRAME.
NO REAL CHANGES TO THE PREVIOUS FORECAST AFTER SUNRISE. CLUSTER OF
CONVECTION WILL LIKELY BE MOVING THROUGH NORTH-CENTRAL AND EAST-
CENTRAL KY DURING THE MORNING HOURS. LOOK FOR CIGS TO DROP INTO THE
MVFR RANGE FOR A TIME BEFORE LIFTING TO VFR AFTER 04/18-20Z. WINDS
DURING THE DAY WILL BE WESTERLY AT 8-10KTS.
LMK WATCHES/WARNINGS/ADVISORIES
KY...NONE.
IN...NONE.
SHORT TERM...MJ
LONG TERM....MJ
AVIATION.....MJ
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