486  
FXUS63 KLMK 201032  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
632 AM EDT WED MAY 20 2026  
   
..UPDATED AVIATION DISCUSSION
 
 
   
KEY MESSAGES
 
 
* PERIODS OF SHOWERS AND STORMS WILL MOVE ACROSS SOUTHERN INDIANA  
AND PORTIONS OF NORTH-CENTRAL KENTUCKY THIS MORNING. HEAVY  
RAINFALL WILL BE POSSIBLE WITH LOCALIZED FLOODING ACROSS SOUTHERN  
INDIANA.  
 
* ANOTHER ROUND OF SHOWERS AND STORMS IS EXPECTED THIS AFTERNOON. A  
MARGINAL RISK OF STRONG/SEVERE STORMS EXISTS ACROSS THE EAST-  
CENTRAL AND EASTERN KENTUCKY WITH DAMAGING WINDS BEING THE MAIN  
THREAT.  
 
* BUSY WEATHER PATTERN WILL RAMP BACK UP LATE THURSDAY AND THROUGH  
THE HOLIDAY WEEKEND WITH EPISODIC BOUTS OF SHOWERS/STORMS WITH  
HEAVY, BUT WELCOME RAINFALL.  
 

 
   
SHORT TERM /THROUGH THURSDAY NIGHT/
 
 
ISSUED AT 316 AM EDT WED MAY 20 2026  
 
BROAD SOUTHWEST FLOW CONTINUES ALOFT ACROSS THE REGION THIS MORNING.  
A SMALL PERTURBATION MOVING NORTHEAST WITHIN THIS FLOW HAS HELPED  
KICK OFF A PERSISTENT BAND OF SHOWERS/STORMS FROM WESTERN KENTUCKY  
INTO SOUTHWESTERN INDIANA. THIS CORRIDOR OF CONVECTION IS ROOTED  
WITHIN THE LOW-LEVEL JET AXIS AND ALSO RESIDES IN A PWAT PLUME  
EXTENDING FROM WEST TN NORTHEASTWARD INTO SOUTHERN INDIANA. WITHIN  
THIS CORRIDOR PWAT VALUES ARE RUNNING IN THE 1.5-1.9 INCH RANGE.  
 
THIS CONVECTION WILL MOVE OFF TO THE NORTHEAST THROUGH THE REMAINDER  
OF THE OVERNIGHT HOURS AND MOVE ACROSS SOUTHERN INDIANA WHERE RECENT  
RAINFALL HAS FALLEN IN THE LAST 24-36 HOURS. THE CONVECTION HAS  
GENERATED SOME COOL OUTFLOW WHICH IS SURGING EASTWARD TOWARD THE I-  
65 CORRIDOR. PWAT VALUES DO DECREASE MARKEDLY EAST OF THE I-65  
CORRIDOR. GIVEN THAT WE HAVE SOME ELEVATED INSTABILITY IN THE I-65  
CORRIDOR AND POINTS WEST, EXPECT THIS OUTFLOW TO GENERATE SOME  
ADDITIONAL SHOWER/STORMS FROM HARTFORD NORTHEAST THROUGH THE  
LOUISVILLE METRO OVER THE NEXT FEW HOURS. SHEAR REMAINS VERY  
MARGINAL HERE, SO SEVERE WEATHER IS NOT ANTICIPATED. HOWEVER, A  
SWATH OF MODERATE TO OCCASIONALLY HEAVY RAINFALL WILL MOVE ACROSS  
SATURATED SOILS OVER SOUTHERN INDIANA AND MAY PRODUCE SOME LOCAL  
HYDRO ISSUES THIS MORNING. CURRENT FLOOD WATCH OVER SOUTHERN  
INDIANA CONTINUES TO LOOK GOOD AND NO HEADLINE CHANGES WILL BE MADE  
WITH THIS FORECAST.  
 
MOVING INTO THE DAYTIME HOURS, SURFACE COLD FRONT OFF TO OUR WEST  
THIS MORNING WILL MOVE INTO THE REGION THIS MORNING AND INTO THE  
AFTERNOON HOURS. AS THIS OCCURS, ANOTHER SMALL PERTURBATION ALOFT  
WILL MOVE NORTHEAST ACROSS THE REGION AND PRODUCE ANOTHER ROUND OF  
CONVECTION ACROSS THE REGION. AS THE COLD FRONT HEADS EASTWARD  
THROUGH KENTUCKY, SOME DIURNAL HEATING WILL BE NOTED ACROSS THE  
CENTRAL AND EASTERN PORTIONS OF THE FORECAST AREA. MLCAPE IS  
FORECAST TO RISE INTO THE 800-1300 J/KG RANGE THIS AFTERNOON. MODEL  
SOUNDINGS SHOW RATHER POOR MID-LEVEL LAPSE RATES, BUT THE LOW-LEVEL  
LAPSE RATES ARE PRETTY STEEP. THAT, ALONG WITH CONVERGENCE ALONG  
THE FRONT SHOULD ALLOW WIDESPREAD SHOWERS WITH SOME EMBEDDED  
THUNDERSTORMS TO TRACK ACROSS THE REGION. SOME OF THE STORMS COULD  
BE STRONG THIS AFTERNOON, MAINLY EAST OF THE I-65 CORRIDOR. MAIN  
THREATS WILL BE HEAVY RAINFALL AND GUSTY THUNDERSTORM WINDS. HIGHS  
TODAY WILL FEATURE A GRADIENT WITH READINGS ONLY REACHING THE LOW-  
MID 70S ACROSS THE WEST, WITH UPPER 70S TO LOWER 80S OUT IN THE I-75  
CORRIDOR.  
 
SURFACE COLD FRONT IS EXPECTED TO CONTINUE EASTWARD THIS EVENING  
WITH SHOWERS ENDING FROM NORTHWEST TO THE SOUTHEAST INTO THE LATE  
OVERNIGHT PERIOD. COOL NORTHERLY FLOW WILL USHER IN SOME COOLER AIR  
INTO THE REGION. LOWS TONIGHT WILL DROP INTO THE MID-UPPER 50S  
ACROSS SOUTHERN INDIANA WITH LOWER 60S ACROSS SOUTHERN KENTUCKY.  
 
FOR THURSDAY, WE'LL SEE A BRIEF PAUSE IN THE WET WEATHER AS THE  
FRONT STALLS OUT TO OUR SOUTH. BLENDED POPS KEEP SOME CHANCES OF  
SHOWERS DOWN ACROSS SOUTHERN KY, BUT THIS LOOKS A BIT TOO AGGRESSIVE  
AND I EXPECT THOSE POPS TO DECREASE OVER THE NEXT FEW RUNS. HIGHS  
ON THURSDAY WILL BE A LITTLE COOLER THAN NORMAL WITH READINGS ONLY  
REACHING THE LOWER 70S OVER SOUTHERN INDIANA AND THE NORTHERN HALF  
OF KENTUCKY. MID-UPPER 70S WILL BE FOUND OVER THE SOUTHERN PART OF  
KENTUCKY. THE STALLED OUT FRONT WILL START TO RETURN NORTHWARD LATE  
THURSDAY NIGHT AS A WARM FRONT. AHEAD OF THAT WARM FRONT, ANOTHER  
ROUND OF SHOWERS IS LIKELY TO DEVELOP IN ADVANCE OF THAT FEATURE.  
LOWS WILL RANGE FROM THE UPPER 50S OVER SOUTHERN INDIANA AND NORTHERN  
KENTUCKY TO THE LOWER 60S OVER SOUTHERN KENTUCKY.  
 

 
   
LONG TERM /FRIDAY THROUGH TUESDAY/
 
 
ISSUED AT 316 AM EDT WED MAY 20 2026  
 
FOR THE EXTENDED PORTION OF THE FORECAST PERIOD, UNSETTLED WEATHER  
LOOKS LIKELY FOR FRIDAY AND THROUGH THE MEMORIAL DAY WEEKEND AS  
BROAD SOUTHWEST FLOW WILL REMAIN IN PLACE ACROSS THE REGION. SEVERAL  
WEAK PERTURBATIONS ALOFT WILL MOVE THROUGH THE REGION BRINGING  
EPISODIC BOUTS/ROUNDS OF SHOWERS AND STORMS TO THE REGION. NOW,  
THIS DOESN'T APPEAR TO BE A TOTAL WASHOUT IN ALL PLACES. HOWEVER,  
SEVERAL ROUNDS OF SHOWERS/STORMS WILL BE MOVING ACROSS THE REGION  
AND WILL BRING HEAVY RAINFALL, LIGHTNING, AND GUSTY WINDS AT TIMES.  
 
THE UPPER LEVEL PATTERN WILL FLATTEN OUT A BIT BY MONDAY WITH A  
POSSIBLE SPLIT FLOW PATTERN DEVELOPING AS WE MAY GET A CUT OFF LOW  
TO DEVELOP OVER PORTIONS OF TEXAS. CONFLUENT FLOW EAST OF THE  
CUTOFF LOW ACROSS THE OHIO VALLEY WILL ALLOW A FRONTAL BOUNDARY TO  
REMAIN NEARLY STATIONARY ACROSS THE REGION AND THIS FEATURE WILL BE  
A FOCUS OF RENEWED CONVECTIVE DEVELOPMENT THROUGH THE END OF THE  
FORECAST PERIOD. MOISTURE TRANSPORT INTO THE REGION WILL BE HIGH  
AND PWATS WILL BE RUNNING WELL ABOVE CLIMATOLOGY HERE. SO PERIODS  
OF HEAVY RAINFALL ARE EXPECTED. THIS RAINFALL WILL BE WELCOME TO  
MUCH OF KENTUCKY THAT HAS SEEN A RATHER DRY PERIOD OF WEATHER OF  
LATE. QPF AMOUNTS OF 2-4 INCHES WILL BE POSSIBLE ACROSS THE REGION  
WITH LOCALLY HIGHER AMOUNTS IN AREAS THAT SEE TRAINING. WHILE MUCH  
OF THIS RAINFALL COULD SEE GOOD INFILTRATION INTO THE GROUND, WE  
COULD END UP SEEING SOME HYDRO PROBLEMS DEVELOP IN AREAS THAT HAVE  
SEEN RECENT RAINFALL.  
 
HIGHS ON FRIDAY WILL GENERALLY BE IN THE UPPER 70S TO THE LOWER 80S.  
TEMPERATURES FOR SATURDAY THROUGH TUESDAY WILL SEE DAYTIME HIGHS  
MAINLY IN THE LOWER 80S WITH OVERNIGHT LOWS IN THE 60S.  
 
LOOKING PAST THE 7 DAY PERIOD, LONGER RANGE GUIDANCE SUGGESTS THAT  
WE COULD SEE SOME HIGH LATITUDE BLOCKING REDEVELOP OVER CANADA WHICH  
WILL RESULT IN A FAIRLY AMPLIFIED FLOW PATTERN ACROSS THE CONUS.  
THERE IS A PRETTY DECENT SIGNAL IN THE DATA SUGGESTING ABOVE NORMAL  
RAINFALL CLOSING OUT MAY AND HEADING INTO EARLY JUNE, THOUGH  
TEMPERATURES LOOK TO REMAIN SEASONAL THROUGH THIS TIME FRAME.  
 

 
   
AVIATION /12Z TAFS THROUGH 18Z THURSDAY/
 
 
ISSUED AT 632 AM EDT WED MAY 20 2026  
 
INITIAL BATCH OF CONVECTION HAS MOVED NORTHEAST OF THE AREA THIS  
MORNING. A SECOND BATCH OF CONVECTION IS MOVING NORTHEAST OUT OF NW  
TN AND WKY AND WILL PRIMARILY AFFECT BWG/SDF/HNB THIS MORNING WITH  
SHOWERS AND LOW CIGS. SURFACE COLD FRONT IS FORECAST TO MOVE  
THROUGH THE REGION TODAY AND WILL LIKELY KICK OFF ANOTHER ROUND OF  
SHOWERS/STORMS THIS AFTERNOON, MAINLY IN THE LEX/RGA AREA. CIGS  
TODAY LOOK TO BE IN THE HIGH IFR/LOW MVFR RANGE WITH VSBYS  
FLUCTUATING BETWEEN VFR/MVFR DUE TO PASSING SHOWERS/STORMS.  
CONVECTION IS FORECAST TO MOVE OFF TO THE EAST THIS EVENING, BUT LOW  
CIGS WILL LIKELY REMAIN IN PLACE OVERNIGHT AND INTO THURSDAY MORNING.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...FLOOD WATCH UNTIL 2 PM EDT THIS AFTERNOON FOR KYZ032.  
IN...FLOOD WATCH UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR  
INZ076>079-083-084-089>092.  
 

 
 

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