756  
FXUS63 KLMK 051044  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
644 AM EDT FRI SEP 5 2025  
   
..UPDATED AVIATION DISCUSSION
 
 
   
KEY MESSAGES
 
 
* COLD FRONT TO PUSH THROUGH THE REGION LATER TONIGHT AND SATURDAY  
BRINGING ANOTHER ROUND OF BENEFICIAL RAINFALL TO THE REGION.  
STRONG TO SEVERE STORMS WILL BE POSSIBLE OUT AHEAD OF THIS FRONT  
THIS EVENING AND INTO THE OVERNIGHT HOURS.  
 
* COOLER AND DRIER AIR WILL RETURN TO THE REGION LATE SATURDAY AND  
INTO SUNDAY. OVERNIGHT LOWS SUNDAY AND MONDAY MORNING MAY BREAK  
RECORD LOW TEMPS. PLEASANT WEATHER IS EXPECTED FOR NEXT WEEK.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 339 AM EDT FRI SEP 5 2025  
 
EARLY MORNING SATELLITE IMAGERY SHOWS PARTLY CLOUDY SKIES ACROSS THE  
REGION. GOES NIGHT-TIME FOG PRODUCT REVEALS A DECENT AMOUNT OF FOG  
IN THE RIVER VALLEYS. A STALLED OUT FRONTAL BOUNDARY HAS BECOME A  
WARM FRONT AND IS LIFTING NORTHWARD ACROSS THE REGION THIS MORNING.  
THE FRONTAL BOUNDARY IS ROUGHLY ALONG THE I-64 CORRIDOR. NORTH OF  
THE FRONT, TEMPERATURES WERE IN THE LOWER 50S ACROSS SOUTHERN  
INDIANA AND FAR NORTHERN KENTUCKY. SOUTH OF THE FRONT, TEMPERATURES  
WERE MAINLY IN THE UPPER 50S TO THE LOWER 60S. A FEW MID 60S WERE  
NOTED DOWN ALONG THE KY/TN BORDER.  
 
FOR THE REMAINDER OF THE OVERNIGHT PERIOD, NO SIGNIFICANT WEATHER IS  
EXPECTED. TEMPS TOWARD SUNRISE WILL BE IN THE MID-UPPER 50S ACROSS  
THE NORTH WITH UPPER 50S/LOWER 60S DOWN ACROSS THE SOUTH.  
 
FOR TODAY, AFOREMENTIONED SURFACE WARM FRONT WILL CONTINUE TO LIFT  
NORTHWARD THIS MORNING. IN ITS WAKE, A BROAD SOUTHWEST FLOW REGIME  
WILL SET UP ACROSS THE REGION. WE EXPECT PARTLY SUNNY SKIES WITH  
BREEZY SOUTHWEST WINDS DEVELOPING BY MID-LATE MORNING AND CONTINUING  
THROUGH THE AFTERNOON HOURS. STRONG DIURNAL HEATING IS EXPECTED AND  
A GRADIENT OF TEMPERATURE WILL BE NOTED ACROSS THE REGION. AFTERNOON  
HIGHS WILL TOP OUT IN THE LOW-MID 80S ACROSS SOUTHERN INDIANA AND  
FAR NORTHERN KENTUCKY. ACROSS CENTRAL KENTUCKY, HIGHS SHOULD TOP  
OUT IN THE MID-UPPER 80S WITH LOWER 90S POSSIBLE, MAINLY SOUTH OF  
THE CUMBERLAND PARKWAY.  
 
AS WE HEAD INTO THE LATE AFTERNOON HOURS, A COLD FRONT AND AN UPPER  
LEVEL SHORTWAVE TROUGH AXIS WILL DROP INTO THE REGION FROM THE  
NORTHWEST. LATEST MODEL RUNS SHOW THAT THE UPPER LEVEL HEIGHT FALLS  
ARE NOT AS STRONG AS THEY HAVE BEEN IN THE PAST FEW DAYS.  
ADDITIONALLY, CONVERGENCE ALONG THE FRONT WILL BE INITIALLY WEAK.  
THEREFORE, MUCH OF THE DAY TODAY WILL FEATURE DRY CONDITIONS, BUT  
SCATTERED CONVECTION WILL LIKELY DEVELOP TOWARD THE EVENING HOURS AS  
CONVERGENCE ALONG THE FRONT STRENGTHENS.  
 
MULTI-MODEL CONSENSUS SOUNDINGS CONTINUE TO SHOW A PLUME OF MODERATE  
INSTABILITY DEVELOPING ACROSS THE REGION. MLCAPE VALUES WILL LIKELY  
INCREASE INTO THE 1500-2500 J/KG RANGE. SHEAR PROFILES REMAIN  
SUPPORTIVE OF ORGANIZED CONVECTION WITH 30-35KTS OF BULK SHEAR  
AVAILABLE, ALTHOUGH THE PROFILE IS GENERALLY UNIDIRECTIONAL HERE.  
WITHIN THIS ENVIRONMENT, SCATTERED DISCRETE CONVECTION WILL LIKELY  
DEVELOP ACROSS PORTIONS OF WESTERN KY/TN. GIVEN THE INITIAL SHEAR  
PROFILES, SOME SUPERCELLULAR STRUCTURES MAY BE SEEN WITH THE INITIAL  
CONVECTION, ALONG WITH A FEW SPLITS. HOWEVER, GIVEN THAT MODEL  
SOUNDINGS SHOW A RATHER LARGE T/TD SPREAD IN THE LOW-LEVELS  
RESULTING IN INVERTED-V SOUNDINGS, UPSCALE GROWTH INTO SEVERAL MULTI-  
CELLULAR CLUSTERS IS THE LIKELY CONVECTIVE EVOLUTION WITH THIS  
SYSTEM.  
 
AS WE MOVE INTO THE MID-LATE EVENING HOURS, FASTER MID-LEVEL FLOW  
LAGGING BEHIND THE FRONTAL BOUNDARY WILL PUSH EASTWARD INTO THE  
REGION. THE RIGHT ENTRANCE REGION OF THE UPPER LEVEL JET SHOULD  
ARRIVE BY MID-LATE EVENING. GOOD SYNOPTIC SCALE LIFT WITH THIS  
REGION AIDED BY AN INCREASE IN THE NOCTURNAL LOW-LEVEL JET SHOULD  
SET THE STAGE FOR CONVECTION TO TRANSITION FROM SURFACE BASED TO  
MORE OF AN ELEVATED NATURE. INDEED, MODEL SOUNDINGS SHOW A FAIR  
AMOUNT OF ELEVATED INSTABILITY INTO THE OVERNIGHT HOURS WHICH SHOULD  
RESULT IN WIDESPREAD CONVECTION FOR MUCH OF THE OVERNIGHT HOURS. AS  
THE SURFACE FRONT PUSHES SOUTHWARD, THE FLOW ALONG THE FRONT WILL  
BECOME MORE PARALLEL TO THE FLOW ALOFT, RESULTING IN SOME  
BACKBUILDING OF CONVECTION. TRAINING OF CONVECTION MAY BECOME AN  
ISSUE ACROSS SOUTHERN KY RESULTING IN SOME LOCALIZED HEAVY RAINFALL  
SWATHS THAT MAY LEAD TO ISOLATED INSTANCES OF FLASH FLOODING.  
 
IN TERMS OF CONVECTIVE HAZARDS, THERE APPEARS TO BE A SHORT WINDOW  
OF OPPORTUNITY FOR SEVERE WEATHER TONIGHT. THE INITIAL CONVECTIVE  
DEVELOPMENT OF DISCRETE CELLS MAY POSE A LOW RISK OF TORNADOES AND  
LARGE HAIL WITH ANY SUSTAINED STRONG CORES. HOWEVER, THE MAIN  
CONVECTIVE HAZARD WILL LIKELY BE DAMAGING WIND GUSTS, ESPECIALLY  
WHERE CELLS TEND TO BOW OUT.  
 
LOWS TONIGHT WILL DROP INTO THE LOW-MID 50S ACROSS SOUTHERN IN AND  
FAR NORTHERN KY, WITH MID-UPPER 50S EXPECTED ACROSS MUCH OF  
CENTRAL/SOUTHERN KY.  
 

 
   
LONG TERM /SATURDAY THROUGH THURSDAY/
 
 
ISSUED AT 339 AM EDT FRI SEP 5 2025  
 
SATURDAY THROUGH MONDAY NIGHT...  
 
CURRENT DATA SUGGESTS THAT THE UPPER LEVEL TROUGH AXIS WILL SWING  
THROUGH THE REGION SATURDAY MORNING. WIDESPREAD SHOWER AND EMBEDDED  
THUNDERSTORMS ARE LIKELY TO BE ONGOING SATURDAY MORNING. HOWEVER,  
THIS ACTIVITY SHOULD PUSH OFF TO THE SOUTH AND EAST DURING THE DAY  
WITH IMPROVING CONDITIONS THROUGH THE AFTERNOON HOURS. DEPENDING ON  
CLOUD COVER, TEMPERATURES WILL BE TRICKY TO FORECAST HERE. WITHIN  
THE CLOUDS AND SHOWERS, TEMPERATURES WILL LIKELY HOLD IN THE UPPER  
50S, BUT THEN RECOVER A BIT IN THE AFTERNOON. FOR NOW, PLAN ON  
GOING WITH MID-UPPER 60S OVER THE EASTERN SECTIONS FOR HIGHS WITH  
LOW-MID 70S OUT ACROSS THE WEST. COLD ADVECTION AND CLEARING SKIES  
WILL ALLOW TEMPS TO DROP INTO THE MID-UPPER 40S SATURDAY NIGHT WHICH  
MAY BREAK SOME RECORD LOWS TEMPS SUNDAY MORNING (MAINLY AT  
LEXINGTON).  
 
DRY AND COOLER CONDITIONS ARE EXPECTED FOR SUNDAY WITH DAYTIME HIGHS  
IN THE LOW-MID 70S ACROSS SOUTHERN IN AND THE NORTHERN HALF OF KY,  
MID-UPPER 70S WILL BE SEEN ACROSS SOUTHERN KY. SUNDAY NIGHT WILL  
LIKELY FEATURE A GOOD RADIATIONAL COOLING NIGHT ACROSS THE REGION.  
LOWS WILL LIKELY DIP INTO THE UPPER 30S/LOWER 40S IN OUR RADIATIONAL  
COOLING SPOTS AND VALLEY LOCATIONS, WITH MID 40S ELSEWHERE. IF THIS  
SCENARIO WORKS OUT, LOW TEMPERATURE RECORDS MAY BE SET ONCE AGAIN.  
 
DRY AND PLEASANT WEATHER IS EXPECTED FOR MONDAY WITH HIGHS THE MID-  
UPPER 70S AND OVERNIGHT LOWS IN THE UPPER 40S TO NEAR 50.  
 
TUESDAY THROUGH THURSDAY...  
 
BROAD TROUGHING IS LIKELY TO HOLD ACROSS THE EASTERN US THROUGH MUCH  
OF NEXT WEEK WITH SOME RIDGING BUILDING INTO THE PLAINS AS A TROUGH  
DEVELOPS ACROSS THE WESTERN CONUS. DRY CONDITIONS ARE EXPECTED  
THROUGH THE PERIOD WITH MODERATING TEMPERATURES. HIGHS ON TUESDAY  
WILL WARM INTO THE LOWER 80S WITH LOW-MID 80S EXPECTED FOR WEDNESDAY  
AND THURSDAY.  
 

 
   
AVIATION /12Z TAFS THROUGH 18Z SATURDAY/
 
 
ISSUED AT 643 AM EDT FRI SEP 5 2025  
 
WILL SEE SOME PATCHY FOG OVER IN THE BLUEGRASS REGION EARLY IN THE  
PERIOD, BUT THIS SHOULD MIX OUT BY 05/13Z. LOOK FOR SOUTHWEST WINDS  
TO PICK UP LATER THIS MORNING AND CONTINUE THROUGH THE AFTERNOON  
HOURS. SUSTAINED WINDS OF 8-10KTS WITH GUSTS TO 20-25KTS WILL BE  
POSSIBLE. SURFACE COLD FRONT WILL PUSH INTO THE REGION THIS EVENING  
WITH SCATTERED SHOWERS/STORMS FIRING OUT AHEAD OF IT. TIMING OF THE  
STORMS HAS BEEN DELAYED BY A FEW HOURS AS NEW GUIDANCE SUGGESTS IT  
MAY BE 05/23Z OR LATER BEFORE CONVECTION DEVELOPS ACROSS THE REGION.  
CLUSTERS OF SHOWERS/STORMS WILL MOVE ACROSS THE REGION OVERNIGHT AND  
INTO SATURDAY MORNING. CIGS LOOK TO REMAIN GENERALLY VFR THOUGH  
SOME MVFR CIGS MAY DEVELOP BY SUNRISE SATURDAY.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...NONE.  
IN...NONE.  
 

 
 

 
 
SHORT TERM...MJ  
LONG TERM....MJ  
AVIATION.....MJ  
 
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