953  
FXUS63 KLMK 121947  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
347 PM EDT WED AUG 12 2026  
   
KEY MESSAGES
 
 
* WAVES OF THUNDERSTORMS INTO TONIGHT COULD GENERATE SEVERE WEATHER,  
WITH DAMAGING WINDS THE PRIMARY HAZARD AND A LOWER RISK FOR LARGE  
HAIL.  
 
* REPEATED ROUNDS OF HEAVY RAINFALL IN THUNDERSTORMS THROUGH THIS  
EVENING COULD RESULT IN FLASH FLOODING. THERE IS A LEVEL 2 OF 4  
(SLIGHT) RISK FOR EXCESSIVE RAINFALL AREA-WIDE, AND A LEVEL 3  
(MODERATE) RISK FOR EXCESSIVE RAINFALL ACROSS SE INDIANA AND NORTH  
CENTRAL KY.  
 
* ADDITIONAL ROUNDS OF STORMS ARE POSSIBLE (20-40% CHANCE) BOTH  
TOMORROW AND FRIDAY, BUT CONFIDENCE IS LOW ON SEVERE WEATHER AND  
FLOODING POTENTIAL EACH DAY.  
 
* OUTSIDE OF STORMS, HEAT INDICES ARE LIKELY (50-80% CHANCE) TO  
SURPASS 100 DEGREES WEST OF I-65 EACH AFTERNOON THROUGH THURSDAY,  
AND AREA-WIDE OVER THE WEEKEND.  
 

 
   
UPDATE
 
 
ISSUED AT 345 PM EDT WED AUG 12 2026  
 
SEVERE THUNDERSTORM WATCH 577 HAS BEEN ISSUED FOR ALL SOUTHERN IN  
COUNTIES AND CENTRAL KY COUNTIES UNTIL 9PM EDT/ 8PM CDT. WE WILL  
CONTINUE TO MONITOR THE DESTABILIZATION WITHIN THE AREA AHEAD OF THE  
BROKEN LINE OF STORMS. MAIN HAZARD FOR STORMS WILL BE DAMAGING  
WINDS, HOWEVER A BRIEF SPIN UP TORNADO CANNOT BE RULED OUT. FLASH  
FLOODING WILL ALSO BE A THREAT THIS EVENING AND INTO THE EARLY  
MORNING HOURS.  
 

 
   
SHORT TERM /THROUGH THURSDAY NIGHT/
 
 
ISSUED AT 228 PM EDT WED AUG 12 2026  
 
THINGS HAVE QUIETED DOWN ACROSS THE CWA AT THIS HOUR, HOWEVER ANY  
LULLS IN ACTIVITY WILL BE PRETTY SHORT-LIVED AS WE GEAR UP FOR THE  
NEXT ROUND OF CONVECTION LATER THIS AFTERNOON THROUGH EVENING. THE  
OUTFLOW BOUNDARY FROM THIS MORNING'S STORMS WAS ABLE TO PUSH  
WESTWARD TO AN OWENSBORO, KY TO SCOTTSVILLE, KY LINE. AREAS TO THE  
EAST OF THIS BOUNDARY HAVE REMAINED IN THE 70S THROUGH THE MORNING  
AND EARLY AFTERNOON, AND HAVE ONLY RECENTLY BEGUN TO RISE INTO THE  
LOW 80S, SIGNALING SOME RECOVERY (BUILDING INSTABILITY) OF THE  
AIRMASS. TO BACK THAT UP, A RECENT ACARS SOUNDING OUT OF SDF SHOWS A  
NOTABLE LOW LEVEL INVERSION IS PRESENT. TO THE WEST OF THE BOUNDARY,  
TEMPERATURES ARE IN THE LOW 90S WITH DEW POINTS RANGING IN THE MID  
TO UPPER 70S. COULD STILL SEE SOME HEAT INDICES IN THE 100 TO 105  
DEGREE RANGE THIS AFTERNOON WEST OF THE BOUNDARY.  
 
THE BIG QUESTION FOR THIS AFTERNOON AND EVENING WILL BE HOW MUCH WE  
ARE ABLE TO DESTABILIZE/RECOVER THE AIRMASS AHEAD OF DEVELOPING  
STORMS UPSTREAM? THE RAP DEPICTION OF SB CAPE RECOVERY ON THE SPC  
MESOANALYSIS PAGE IS QUITE DRAMATIC WITH A QUICK RECOVERY, AND STILL  
HAS OUR AREA DE-STABILIZING TO 4000-5000 J/KG BY LATE AFTERNOON.  
THINKING THIS IS A LITTLE OVERDONE GIVEN WHERE WE ARE CURRENTLY, AND  
LIKE THE 12/12Z HREF DEPICTION OF MORE AROUND 2000-2500 J/KG OF ML  
CAPE BY LATE AFTERNOON. WE ARE CURRENTLY SEEING QUITE A BIT OF  
HEATING WHERE THE CLOUDS HAVE CLEARED, HOWEVER THIS WINDOW MAY ALSO  
BE PRETTY SHORTLIVED AS CONVECTIVE DEBRIS FROM THE UPSTREAM SYSTEM  
WILL SOON BE OVERSPREADING THE AREA.  
 
SOME OF THE LATEST RUNS OF THE HI-RES DATA DO SUGGEST THAT A  
DEVELOPING CONVECTIVE COMPLEX WILL MAKE IT INTO OUR AREA, HOWEVER  
THEY MAY BE A LITTLE OVERDONE ON INTENSITY IF WE AREN'T ABLE TO  
FULLY RECOVER. IN CONTRAST, IF WE DO QUICKLY DESTABILIZE THEN WE  
WILL BE IN PLAY FOR ANOTHER EVENING OF DAMAGING WIND THREATS,  
ESPECIALLY IF A GOOD COLD POOL IS ABLE TO GET ESTABLISHED UPSTREAM  
AHEAD OF TIME. SPC DID EXPAND THE SLIGHT RISK OVER OUR ENTIRE AREA,  
WHICH SUGGESTS THE MORE UNSTABLE SOLUTION, AND RECENT COLLABORATION  
WITH THEM HAS SUGGESTED THAT A SEVERE THUNDERSTORM WATCH IS  
POSSIBLE, BUT WE ARE GOING TO WAIT AND SEE HOW WE DESTABILIZE.  
TIMING STILL LOOKS PRETTY GOOD FOR STORM ARRIVAL AROUND 4 OR 5 PM  
EDT ACROSS OUR NORTHERN CWA, PUSHING SOUTH THROUGH THE CWA INTO THE  
EVENING, AND EXITING OUR SE AROUND 10 PM EDT OR SO. WE'LL ALSO HAVE  
TO WATCH FOR ANY HEAVY RAINFALL TO DEVELOP INTO A FLASH FLOODING  
CONCERN, PARTICULARLY ACROSS AREAS THAT SAW A LOT OF RAIN LAST NIGHT  
AND THIS MORNING. ESSENTIALLY WHERE WPC HAS DRAWN THE MODERATE RISK.  
 
AFTER THE EVENING WAVE PUSHES THROUGH WE DO EXPECT A BRIEF LULL IN  
ACTIVITY. HOWEVER WE MAY SEE A SIMILAR SCENARIO SET UP THROUGH THE  
OVERNIGHT TO WHAT OCCURRED LAST NIGHT. THE REMNANT CONVECTIVELY  
REINFORCED OUTFLOW IS EXPECTED TO SET UP IN A MORE W-E FASHION  
SOMEWHERE AROUND THE I-64 CORRIDOR. HERE, WE COULD GET REDEVELOPMENT  
OF SHOWERS AND STORMS OVERNIGHT AS THE BOUNDARY STALLS ROUGHLY  
PARALLEL TO THE UPPER FLOW AND THERE IS AT LEAST SOME MODEST LOW  
LEVEL JET CONTRIBUTION TO MOISTURE TRANSPORT. MUCH LIKE LAST NIGHT,  
THE 12/12Z HREF SUGGESTS SOME VERY IMPRESSIVE RAINFALL TOTALS FROM  
THE MAX ENSEMBLE MEMBER, AND HAS SOME SUPPORT FROM THE PMM DATA AS  
WELL. IN ADDITION, THE 12/12Z HRRR ALSO PEGGED A BULLSEYE OF 5+"  
ACROSS SOUTHWEST IN IN A LOCALIZED AREA. FORECAST MODELS THIS  
AFTERNOON CONTINUE TO SUGGEST SOME TRAINING OF STORMS IN THAT AREA  
THROUGH THE OVERNIGHT, SO FELT IT PRUDENT TO EXTEND THE FLOOD WATCH  
ACROSS SOUTHERN INDIANA THROUGH 12Z THURSDAY MORNING TO ACCOUNT FOR  
THIS THREAT. NOT A SLAM DUNK, BUT ALSO COULD HAVE SOME LOCALIZED  
HIGH END FLOODING IMPACTS LIKE WE SAW LAST NIGHT ACROSS EAST CENTRAL  
IN. SAME SETUP, JUST A DIFFERENT ORIENTATION.  
 
A LOT OF WHAT HAPPENS THIS EVENING AND TONIGHT COULD HAVE A BEARING  
ON WHAT HAPPENS GOING INTO TUESDAY. WHEREVER THE REMNANT BOUNDARY  
SETS UP WILL BE THE FOCUS FOR ADDITIONAL SHOWER AND STORM ACTIVITY  
THROUGH THE AFTERNOON AND EVENING. THE NW FLOW PATTERN ALOFT WILL  
CONTINUE ON THE NE PERIPHERY OF THE UPPER RIDGE SO THIS SHOULD KEEP  
MOST OF THE CONVECTIVE ACTIVITY ACROSS THE NORTHERN AND EASTERN  
PORTIONS OF THE CWA. ADDITIONAL DAMAGING WIND THREATS MAY DEVELOP  
ALONG WITH A LINGERING FLOOD THREAT, OR ENHANCED FLOOD THREAT IF IT  
IS STILL ONGOING FROM ANY OVERNIGHT ACTIVITY. OUR SW CWA WOULD BE  
MOST LIKELY TO GET IN ON A HEAT ADVISORY TOMORROW, BUT WILL AGAIN  
TAKE A WAIT AND SEE APPROACH GIVE CONVECTIVE ACTIVITY AND THE  
POTENTIAL TO BUST A TEMP FORECAST.  
 

 
   
LONG TERM /FRIDAY THROUGH WEDNESDAY/
 
 
ISSUED AT 228 PM EDT WED AUG 12 2026  
 
*** FRIDAY THROUGH MID NEXT WEEK ***  
 
A WEAK SHORTWAVE TROUGH WILL BRING CHANCES FOR SOME RAIN SHOWERS ON  
FRIDAY, HOWEVER CONFIDENCE IS LOW IN TIMING OR INTENSITY AT THIS  
TIME. AN UPPER LEVEL RIDGE WILL BEGIN TO BUILD OVER THE REGION AT  
THE END OF THE WEEK INTO THE WEEKEND. THIS WILL BRING IN A WARMER  
AND SLIGHTLY DRIER AIR MASS TO THE OHIO VALLEY. MAXIMUM TEMPERATURES  
FOR THE WEEKEND ARE EXPECTED TO BE IN THE MID TO UPPER 90S, WITH  
HEAT INDICES POTENTIALLY REACHING TRIPLE DIGITS.  
 
MOVING INTO EARLY NEXT WEEK, A FRONTAL BOUNDARY IS FORECASTED TO  
MOVE THROUGH THE AREA FROM THE NW. THIS WILL BRING RAIN CHANCES BACK  
INTO THE FORECAST AND POSSIBLY A BRIEF RELIEF IN TEMPERATURES.  
HOWEVER, THIS IS NOT EXPECTED TO LAST LONG AS ANOTHER WARM AIRMASS  
WILL MOVE BACK INTO FOR THE MIDDLE OF THE WEEK.  
 

 
   
AVIATION /18Z TAFS THROUGH 00Z FRIDAY/
 
 
ISSUED AT 123 PM EDT WED AUG 12 2026  
 
ADDITIONAL ROUNDS OF SHOWERS AND STORMS WILL MOVE THROUGH THE AREA  
THIS EVENING/TONIGHT INTO TOMORROW. ALL SITES HAVE PROB30 GROUPS FOR  
A BROKEN LINE OF STORMS THIS EVENING, AND SCATTERED SHOWERS/STORMS  
EARLY TOMORROW. WINDS WILL BE VARIABLE THROUGH THE NIGHT WITH STORMS  
AND DEVELOPING OUTFLOW BOUNDARIES. TOMORROW AFTERNOON WINDS SHOULD  
BE PRIMARILY LIGHT AND FROM THE WSW. CLOUD CEILINGS ARE EXPECTED TO  
STAY VFR, OUTSIDE OF MVFR STORM CLOUD BASES.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...FLOOD WATCH THROUGH THURSDAY MORNING FOR KYZ025-029>043-  
047>049-055>057-066-067.  
IN...FLOOD WATCH THROUGH THURSDAY MORNING FOR INZ076>079-083-084-  
089>092.  
 

 
 

 
 
UPDATE...CAL  
SHORT TERM...BJS  
LONG TERM...CAL  
AVIATION...CAL  
 
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