252  
FXUS63 KLMK 131318  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
918 AM EDT TUE MAY 13 2025  
   
KEY MESSAGES
 
 
* SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED THIS  
AFTERNOON AND EVENING, LINGERING INTO WEDNESDAY. HEAVY RAINFALL,  
LIGHTNING, AND GUSTY WINDS ARE THE MAIN THREATS.  
 
* A WARMING TREND IS EXPECTED LATER IN THE WEEK, WITH HIGHS WELL  
INTO THE 80S THURSDAY AND FRIDAY. THE POTENTIAL FOR WAVES OF  
STRONG, POSSIBLY SEVERE STORMS LATE THURSDAY THROUGH FRIDAY NIGHT  
IS INCREASING.  
 

 
   
UPDATE
 
 
ISSUED AT 918 AM EDT TUE MAY 13 2025  
 
THE PATCHY FOG WHICH WAS LOCATED ACROSS PORTIONS OF SOUTH CENTRAL  
AND WEST CENTRAL KENTUCKY IS MIXING OUT AT THIS TIME, WITH  
VISIBILITIES IMPROVING IN LATEST SURFACE OBS AND MESONET IMAGERY.  
THIS LOW-LEVEL MOISTURE IS MIXING UP INTO A STRATOCU LAYER ACROSS  
MOST OF THE AREA, ALTHOUGH MID-LEVEL CLOUDS AND SHOWERS ACROSS  
PORTIONS OF THE BLUEGRASS HAS SLOWED THE DIURNAL WARMING/MIXING  
PROCESS IN THOSE AREAS.  
 
WHILE WE'VE ALREADY SEEN SOME SCATTERED SHOWERS ALONG THE I-75  
CORRIDOR AS WELL AS AROUND THE LOUISVILLE METRO, COVERAGE OF SHOWERS  
IS STILL EXPECTED TO INCREASE AROUND MIDDAY AS WE HIT AND EXCEED  
CONVECTIVE TEMPERATURES. WHILE CONVECTIVE INITIATION SHOULD BE  
FAIRLY RANDOM, WOULD EXPECT ENHANCED COVERAGE NEAR A SUBTLE SFC  
PRESSURE TROUGH ALONG AND EAST OF THE I-65 CORRIDOR.  
 
THE FORECAST IS ON TRACK AT THIS TIME, WITH ONLY MINOR UPDATES TO  
NEAR TERM TEMPERATURES AND POPS.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 308 AM EDT TUE MAY 13 2025  
 
A COUPLE OF VORTMAXES WRAPPING AROUND EACH OTHER ARE MAKING UP THE  
BROAD UPPER LOW DOMINATING OUR WEATHER EARLY THIS MORNING. THE  
NORTHWEST IS NOTED BOTH IN WATER VAPOR IMAGERY AS WELL AS WITH THE  
BROAD CLUSTER OF SHOWERS/OCCASIONAL STORMS OVER FAR SOUTHWEST IN AND  
SOUTHERN IL. THE TROUGH BETWEEN THE TWO IS ALLOWING SOME SHOWERS  
OVER OUR WESTERN COUNTIES THIS HOUR.  
 
AS THE DAY WARES ON, THE SOUTHERN VORTMAX WILL MEANDER INTO OUR  
AREA. AS WE GET EVEN A LITTLE BIT OF HEATING, WE SHOULD SEE NUMEROUS  
SHOWERS AND SOME STORMS POP UP QUICKLY AROUND LUNCHTIME AND  
CONTINUING THROUGH THE AFTERNOON. ANY LOCATION WILL HAVE A FAIRLY  
HIGH RAIN CHANCE FOR THE DAY, BUT OVERALL AMOUNTS ARE NOT TOO  
IMPRESSIVE. THAT SAID THOUGH, WILL HAVE TO WATCH FOR INDIVIDUAL  
STRONGER CELLS...AS STORM MOTIONS WON'T BE TOO FAST. OTHERWISE, NOT  
CONCERNED ABOUT SEVERE POTENTIAL, GIVEN WIDESPREAD CLOUD COVER  
HELPING LIMIT INSTABILITY.  
 
CONVECTIVE COVERAGE WILL WEAKEN QUICKLY WITH SUNSET, THOUGH AN  
ISOLATED SHOWER/STORM CAN'T BE RULED OUT THROUGH THE EVENING. AFTER  
HIGHS IN THE MID TO UPPER 70S TODAY, LOOK FOR LOWS TO FALL OFF INTO  
THE LOWER 60S FOR MOST TONIGHT...EVEN A FEW UPPER 50S.  
 

 
   
LONG TERM /WEDNESDAY THROUGH MONDAY/
 
 
ISSUED AT 308 AM EDT TUE MAY 13 2025  
 
WEDNESDAY WE START TO GET OUT OF THE INFLUENCE OF THE UPPER LOW AS  
IT BOTH FILLS IN SOME AND GETS REPLACED LOCALLY BY SHORTWAVE RIDGING  
MOVING INTO THE MS VALLEY. THE BETTER MOISTURE AND RESIDUE OF THAT  
LOW LIKELY WILL SPARK MORE COVERAGE OF SHOWERS/STORMS IN THE  
AFTERNOON ACROSS THE EASTERN HALF OF THE STATE, INCLUDING OUR  
BLUEGRASS COUNTIES. ACTIVITY SHOULD QUICKLY DIE DOWN BY EVENING.  
 
THURSDAY, THAT RIDGING WILL HAVE ITS AXIS RIGHT OVER US. SOUNDINGS  
SHOW THE STRONG CAP ALOFT. STRONG SOUTHERLY SURFACE FLOW THROUGH THE  
DAY LIKELY WILL BRING US OUR WARMEST DAY OF THE YEAR SO FAR.  
QUESTION MARK IS, ARE WE TOO GREEN TO GET THAT FIRST 90? RAW NBM #'S  
LOOK GOOD WITH 88 FOR SDF. REGARDLESS, WITH DEWPOINTS LIKELY AT  
LEAST IN THE MID TO UPPER 60S THURSDAY AFTERNOON, THAT DAY WILL BE  
MUGGY.  
 
SPEAKING OF THAT CAP, CONVECTIVE TEMPERATURES ARE IN THE MID 90S,  
PER GFS FORECAST SOUNDING AT SDF THURSDAY AFTERNOON. THERE'S QUITE A  
BIT OF ELEVATED ABOVE THAT CAP AS WELL AS NICE SHEAR. AS MENTIONED  
IN THE PREVIOUS DISCUSSION, THE MAIN CONCERN WILL BE, CAN SOMETHING  
DEVELOPING UPSTREAM THAT ORGANIZES AND PUSHES EASTWARD WITHIN THE  
ZONAL FLOW ALOFT...OR EVEN SOUTHEASTWARD ALONG ANY GRADIENTS. IF IT  
CAN, THEN IT WILL HAVE PLENTY OF ENERGY TO GOBBLE UP AS IT  
APPROACHES...POTENTIALLY THURSDAY EVENING. 00Z EURO HINTS AT THE  
LATTER POTENTIAL, WITH A NORTHERN IL/IN BORDER LINE AT 00Z LAYING  
OUT EAST/WEST INTO SE IN BY 06Z. EARLY NSSL ML SEVERE GUIDANCE IS  
FOCUSED ON INDIANA WITH HIGHEST PROBS, THOUGH IT DOES SEEM TO HAVE  
AN OVERLY LARGE AREA OF RELATIVELY HIGH RISK THROUGH ALL OF KY FOR  
THE LATE THU PERIOD.  
 
FRIDAY'S ACTIVITY WILL DEPEND GREATLY ON WHAT DOES BECOME OF  
ACTIVITY THURSDAY EVENING. THE MORE LIKELY SOLUTION ALLOWS FOR NEW  
DEVELOPMENT DURING THE DAY...AS THE CAP IS NOT QUITE AS STRONG AS  
THURSDAY'S. SHORTWAVE ENERGY RIDING IN AHEAD OF AN UPPER TROUGH BY  
LATER FRIDAY AFTERNOON SHOULD ALLOW A COMPLEX OF STORMS TO DEVELOP.  
ONCE AGAIN THE QUESTION OF SEVERITY COMES IN. IF WE GO WITH A  
CLEANER SOLUTION TO START WITH, THEN WITH ANOTHER RELATIVELY HOT AND  
MUGGY DAY, WE'LL HAVE PLENTY OF INSTABILITY TO WORK WITH. THAT  
ENERGY ALOFT WILL PROMOTE THE SEVERE POTENTIAL...WITH ALL HAZARDS ON  
THE TABLE.  
 
SATURDAY WE SHOULD GET A BRIEF PAUSE IN THE RAIN CHANCES AS THE  
FRIDAY SYSTEM STABILIZES US A BIT. SUNDAY COULD SEE ANOTHER IMPULSE  
MOVE THROUGH OUR BRIEFLY ZONAL FLOW ALOFT BEFORE RIDGING TRIES TO  
BUILD IN. NBM IS NOT OVERLY CONVINCED IN THE STRENGTH OF THIS  
RIDGE...GIVEN SOME TIMING DIFFERENCE IN THE VARIOUS MODEL CAMPS.  
THUS A SOLUTION LEANING CLOSER TO CLIMO IS FAVORED.  
 

 
   
AVIATION /12Z TAFS THROUGH 18Z WEDNESDAY/
 
 
ISSUED AT 740 AM EDT TUE MAY 13 2025  
 
UPPER LOW PRESSURE SYSTEM AND ASSOCIATED SFC LOW CONTINUES TO  
APPROACH THE AREA FROM THE SOUTH THIS MORNING, AND SHOULD BE  
OVERHEAD THIS AFTERNOON AND EVENING. LOW-LEVEL MOISTURE HAS PRODUCED  
A MIX OF FOG AND STRATUS WHICH SHOULD MIX INTO A STRATOCU LAYER  
LATER THIS MORNING. THIS AFTERNOON, SCATTERED TO NUMEROUS SHOWERS,  
WITH SOME EMBEDDED THUNDERSTORMS, ARE EXPECTED TO DEVELOP ACROSS THE  
AREA. THE EARLY-TO-MID AFTERNOON TIME FRAME LOOKS TO BE THE MOST  
LIKELY TIMEFRAME FOR TSRA, SO HAVE GONE WITH PROB30 MENTION GIVEN  
THE OVERALL LACK OF ORGANIZATION AND RANDOM DEVELOPMENT OF STORMS.  
OUTSIDE OF STORMS, PREVAILING VFR CONDITIONS ARE LIKELY FOR THIS  
AFTERNOON AND EVENING. TOWARD THE END OF THE CURRENT TAF PERIOD  
WEDNESDAY MORNING, CEILINGS AND VISIBILITY MAY TRY TO DROP AGAIN TO  
MVFR/IFR LEVELS; HOWEVER, FORECAST CONFIDENCE IS LOW.  
 

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

 
 

 
 
UPDATE...CSG  
SHORT TERM...RJS  
LONG TERM...RJS  
AVIATION...CSG  
 
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