260  
FXUS63 KLMK 171112  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
712 AM EDT THU JUL 17 2025  
   
KEY MESSAGES
 
 
* AN ACTIVE WEATHER DAY IS EXPECTED ACROSS THE REGION WITH SCATTERED  
TO NUMEROUS SHOWERS AND THUNDERSTORMS EXPECTED THIS AFTERNOON AND  
EVENING. STORMS COULD HAVE STRONG DOWNBURST/MICROBURSTS RESULTING  
IN LOCALIZED DAMAGING WINDS.  
 
* TORRENTIAL RAINFALL IS EXPECTED WITH THE STORMS THIS AFTERNOON AND  
FLASH FLOODING MAY OCCUR. THE HIGHEST RISK OF FLASH FLOODING WILL  
BE ACROSS SE INDIANA AND INTO THE BLUEGRASS REGION.  
 
* OUTSIDE OF STORMS, NEAR ADVISORY LEVELS OF HEAT/HUMIDITY ARE  
EXPECTED WITH AFTERNOON HEAT INDEX READINGS REACHING THE UPPER 90S  
TO THE LOWER 100S.  
 
* A CONTINUED ACTIVE PATTERN CONTINUES INTO THE WEEKEND AND EARLY  
NEXT WEEK, WITH DAILY CHANCES FOR SHOWERS AND STORMS. HOT AND  
HUMID WEATHER IS ALSO EXPECTED TO CONTINUE.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 711 AM EDT THU JUL 17 2025  
 
EARLIER CONVECTION HAS DIMINISHED ACROSS THE REGION. IN THE WAKE OF  
THE EVENING CONVECTION, SKIES WERE CLEAR TO PARTLY CLOUDY ACROSS THE  
REGION WITH TEMPERATURES IN THE LOW-MID 70S. WINDS REMAIN LIGHT  
ACROSS THE REGION WHICH WILL LIKELY LIMIT OVERALL FOG FORMATION WITH  
THE EXCEPTION OF THE PROTECTED VALLEYS. THROUGH SUNRISE, NO  
SIGNIFICANT WEATHER IS EXPECTED WITH TEMPERATURES REMAINING IN THE  
LOW-MID 70S.  
 
FOR TODAY, A RATHER ACTIVE DAY OF WEATHER IS EXPECTED. A WEAK  
SURFACE COLD FRONT WILL DROP INTO THE I-70 CORRIDOR THIS MORNING AND  
IT PROBABLY WILL NOT MAKE IT MUCH FURTHER SOUTH DURING THE DAY. TO  
THE SOUTH OF THIS BOUNDARY, A RATHER CONVERGENT LOW-LEVEL FLOW WILL  
DRAW AMPLE MOISTURE INTO THE REGION WITH SURFACE DEWPOINTS REMAINING  
IN THE LOW-MID 70S. WITH INSOLATION DURING THE MORNING, WE'LL SEE  
AMPLE INSTABILITY DEVELOP WITH SCATTERED SHOWERS AND STORMS EXPECTED  
TO FIRE BY LATE MORNING. A GRADUAL UPSCALE GROWTH INTO MULTIPLE  
CLUSTERS IS EXPECTED. WHILE INSTABILITY WILL BE FAIRLY HIGH ACROSS  
THE REGION (3500-4500 J/KG), DEEP LAYER SHEAR CONTINUES TO LOOK LESS  
THAN 20KTS. VERY WARM CLOUD DEPTHS ARE EXPECTED ONCE AGAIN, SO  
WATER LOADED DOWNDRAFTS PRODUCING STRONG GUSTY WINDS AND INTENSE CG  
LIGHTNING WILL BE THE MAIN SEVERE THREATS. WITH PWATS REMAINING IN  
THE 2.1-2.2 INCH RAIN, TORRENTIAL RAINFALL IS EXPECTED WITH THESE  
STORMS. THE GOOD NEWS IS THAT THE ENVIRONMENTAL FLOW WILL KEEP  
STORMS MOVING, HOWEVER, STORMS MAY HAVE A TENDENCY TO TRAIN ACROSS  
PORTIONS OF THE REGION AND THAT COULD PRODUCE SOME FLOODING ISSUES.  
 
LOOKING AT THE LAST FEW DAYS OF RAINFALL ACROSS THE STATE, MOST  
AREAS HAVE SEEN RAINFALL, BUT THERE HAVE BEEN A FEW CORRIDORS WHERE  
LOCALLY HEAVIER RAINFALL HAS BEEN OBSERVED. TONIGHT'S DATASETS  
CONTINUE TO SUGGEST HEAVIER RAINFALL ACROSS SE INDIANA AND DOWN INTO  
THE BLUEGRASS REGION. THIS AREA HAS SEEN SOME GOOD RAINFALL IN THE  
LAST 24-36 HOURS. AFTER COORDINATING WITH SURROUNDING OFFICES,  
WE'RE GOING TO HOIST A FLOOD WATCH ACROSS OUR NE SECTIONS WITH  
ILN/JKL FOR THIS AFTERNOON/EVE ACTIVITY. THIS AREA IS WHERE WE  
CURRENTLY THING THAT FLASH FLOODING MAY BE MOST CONCENTRATED.  
 
OUTSIDE OF THE RAINFALL/STORM THREAT, IT WILL BE A RATHER HOT/HUMID  
DATA ACROSS THE AREA WITH HIGHS IN THE UPPER 80S/LOWER 90S. THOSE  
TEMPS COMBINED WITH DEWPOINTS IN THE LOW-MID 70S WILL LIKELY PRODUCE  
HEAT INDICES IN THE UPPER 90S TO THE LOWER 100S. CONFIDENCE HERE  
FOR MEETING CRITERIA IS LOW BECAUSE IT IS POSSIBLE THAT CONVECTIVE  
COVERAGE MAY FOIL OUR AFTERNOON HEATING AND POTENTIALLY LIMIT  
HEATING IN SOME AREAS.  
 
FOR TONIGHT, ONGOING CONVECTION SHOULD BE IN PROGRESS THIS EVENING  
ACROSS THE AREA. CONVECTION SHOULD DIMINISH AFTER SUNSET WITH THE  
LOSS OF HEATING. WITH THE FRONT REMAINING NORTH OF THE REGION,  
OVERNIGHT LOWS WILL ONLY DROP INTO THE LOWER-MIDDLE 70S. WITH THE  
EXPECTATION OF CONVECTION DIMINISHING AROUND MIDNIGHT, WE'LL LET THE  
FLOOD WATCH GO UNTIL THEN. HOWEVER, THERE IS SOME SIGNALING IN THE  
GUIDANCE THAT ADDITIONAL SHOWER/STORMS MAY DEVELOP LATER IN THE  
NIGHT. SHOULD THAT OCCUR, AN EXTENSION OF THE FLOOD WATCH MAY BE  
REQUIRED IN SUBSEQUENT FORECASTS.  
 

 
   
LONG TERM /FRIDAY THROUGH WEDNESDAY/
 
 
ISSUED AT 711 AM EDT THU JUL 17 2025  
 
REMNANT FRONTAL BOUNDARY WILL REMAIN JUST NORTH OF THE REGION ON  
FRIDAY AND A TROPICAL AIRMASS WILL REMAIN IN PLACE ACROSS THE  
REGION. GIVEN ANTICIPATED CONVECTIVE COVERAGE THU/THU NIGHT,  
LINGERING CONVECTIVE CLOUD DEBRIS WILL LIKELY BE NOTED ACROSS THE  
REGION ON FRIDAY KEEPING HIGH TEMPERATURES IN THE UPPER 80S TO NEAR  
90. SHEAR ACROSS THE REGION WILL REMAIN RATHER WEAK, BUT WE'LL SEE  
THE TYPICAL DIURNAL INCREASE IN INSTABILITY ACROSS THE REGION WHICH  
SHOULD SUPPORT AT LEAST SCATTERED CONVECTION ONCE AGAIN. MAINLY  
PULSE-TYPE STORMS ARE EXPECTED WITH WATERLOADED DOWNDRAFTS, THOUGH  
OVERALL COVERAGE MAY BE A BIT MORE LIMITED ON FRIDAY WITH LESS  
INSTABILITY AND LACK OF FOCUSED FORCING. HEAVY RAINFALL WITH STORMS  
WILL BE POSSIBLE AS PWATS REMAIN AT/ABOVE 2 INCHES. LOWS FRIDAY  
NIGHT WILL DROP BACK INTO THE LOW-MID 70S.  
 
FOR THE WEEKEND AND INTO NEXT WEEK, THE UPPER LEVEL PATTERN IS NOT  
EXPECTED TO CHANGE MUCH. THE SE RIDGE LOOKS TO REMAIN ENTRENCHED  
ACROSS THE AREA WITH PERHAPS A SLIGHT RETROGRESSION TO THE WEST.  
SLIGHT RIDGING MAY TAKE PLACE ACROSS THE PLAINS WHICH WILL RESULT IN  
A MORE NORTHWEST FLOW REGIME ACROSS THE OHIO VALLEY. MULTIPLE  
PERTURBATIONS MOVING THROUGH WITHIN THE FLOW PATTERN WILL LIKELY  
PRODUCE EPISODIC BOUTS OF CONVECTION. MODEL SOUNDINGS THROUGH THE  
PERIOD CONTINUE TO SHOW RATHER WEAK SHEAR, BUT AMPLE DIURNAL  
INSTABILITY DEVELOPING. WITH A TROPICAL AIRMASS REMAINING IN PLACE,  
HEAVY RAINFALL WITH STORMS WILL REMAIN A THREAT. THE NORTHWEST FLOW  
PATTERN COULD RESULT IN MULTIPLE MCSS THAT COULD DROP DOWN INTO THE  
REGION. CURRENT THINKING IS THAT NORTHERN IL/CENTRAL IN AND DOWN  
INTO NORTHEAST/EASTERN KY COULD SEE THE MOST CONVECTIVE ACTION HERE  
ALONG WITH A THREAT OF FLASH FLOODING.  
 
OUTSIDE OF STORMS, IT WILL REMAIN HOT AND MUGGY WITH DAYTIME HIGHS  
IN THE UPPER 80S TO AROUND 90 AND OVERNIGHT LOWS IN THE LOW-MID 70S.  
 

 
   
AVIATION /12Z TAFS THROUGH 18Z FRIDAY/
 
 
ISSUED AT 711 AM EDT THU JUL 17 2025  
 
GENERALLY VFR CONDITIONS ARE EXPECTED THIS MORNING AND INTO THE  
AFTERNOON HOURS WITH A LIGHT SOUTHWEST WIND EXPECTED. AS WE MOVE  
INTO THE AFTERNOON, EXPECT SCATTERED SHOWERS AND STORMS TO BECOME  
MORE NUMEROUS ACROSS SOUTHERN INDIANA AND NORTH-CENTRAL KENTUCKY.  
HAVE TRIED TO ADD SOME TIGHTER TIMINGS IN HERE FOR STORMS THIS  
AFTERNOON WITH THIS FORECAST PACKAGE. CURRENT THINKING IS THAT BEST  
TIMES FOR STORMS AT HNB/SDF/LEX/RGA WILL BE IN THE 17/20-24Z TIME  
FRAME. LOOK FOR TEMPO DROPS TO IFR IN STORMS WITH WIND GUSTS OF 30-  
35KTS IF A STORM WAS TO IMPACT THE TERMINAL. COVERAGE DOWN IN THE  
BWG AREA IS A LITTLE MORE UNCERTAIN SO HAVE CONTINUED PROB30S DOWN  
THERE FOR THE 17/20Z-18/01Z TIME FRAME.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH THIS EVENING  
FOR KYZ031>043-047>049-055>057-067.  
IN...FLOOD WATCH FROM 2 PM EDT THIS AFTERNOON THROUGH THIS EVENING  
FOR INZ079.  
 

 
 

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