105  
FXUS63 KLMK 190513  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
113 AM EDT TUE MAY 19 2026  
   
..UPDATED MESOSCALE AND AVIATION DISCUSSIONS  
 
   
KEY MESSAGES  
 
* TODAY THROUGH TUESDAY, TEMPERATURES ARE EXPECTED TO WARM INTO THE  
MID 80S TO LOW 90S. SOME DAILY MAX TEMPERATURE RECORDS COULD BE  
CHALLENGED.  
 
* THIS AFTERNOON/EVENING, SHOWERS AND/OR THUNDERSTORMS ARRIVE,  
ESPECIALLY FOR OUR NORTHWESTERN COUNTIES. THIS IS MAINLY A WIND  
AND HAIL THREAT.  
 
* A LINE OF STRONG TO SEVERE STORMS IS EXPECTED TO MOVE THROUGH  
AHEAD OF A COLD FRONT ON TUESDAY, POSSIBLY BRINGING STRONG WINDS  
AND HAIL. THE LINE WILL WEAKEN AS IT MOVES EAST OVER THE REGION.  
 
* MORE ACTIVE WEATHER ARRIVE LATER THIS WEEK AS MULTIPLE ROUNDS OF  
SHOWERS AND SCATTERED THUNDERSTORMS ARE POSSIBLE GOING  
INTO MEMORIAL DAY WEEKEND.  
 
 
   
MESOSCALE  
 
ISSUED AT 112 AM EDT TUE MAY 19 2026  
 
CONVECTION ACROSS SOUTHERN INDIANA CONTINUES TO WIND DOWN QUICKLY.  
WILL STILL SEE SOME LIGHT TO MODERATE RAIN MOVE ACROSS PORTIONS OF  
CRAWFORD/HARRISON/WASHINGTON/FLOYD AND CLARK COUNTIES OVER THE NEXT  
HOUR TO 90 MIN. ONGOING FLOODING WILL LIKELY BE FOCUSED IN EASTERN  
WASHINGTON AND WESTERN CLARK COUNTIES. CONDITIONS ARE LIKELY TO  
IMPROVE OVERNIGHT AS RAINFALL ENDS AND WATER RECEDES.  
 
ISSUED AT 1011 PM EDT MON MAY 18 2026  
 
CONVECTION CONTINUES TO SLOWLY MOVE EASTWARD ACROSS SOUTHERN INDIANA  
THIS EVENING. WE'RE WATCHING A SW-NE ORIENTED BAND OF VERY HEAVY  
RAINFALL WITH SOME EMBEDDED THUNDERSTORMS THAT WILL TRAIN ACROSS  
PORTIONS OF MEADE, HARRISON, CLARK, AND FLOYD COUNTIES IN SOUTHERN  
INDIANA OVER THE NEXT FEW HOURS.  
 
OVERALL, ATMOSPHERE IS MARGINALLY UNSTABLE WITH ABOUT 500-700 J/KG  
OF MLCAPE AND ABOUT 30-35KT OF BULK SHEAR. THE ONGOING CONVECTION  
RESIDES WITHIN AN ENHANCED PWAT PLUME WITH VALUES 1.6-1.9 INCHES.  
WITH DEEP LAYER SHEAR LARGELY PARALLEL TO THE SYNOPTIC SCALE ASCENT  
PATTERN, EXPECT THIS CONVECTION TO SLOWLY MOVE EASTWARD WITH TIME  
WHILE WEAKENING. LATEST CAM GUIDANCE SUGGESTS THAT THIS ACTIVITY  
WILL DIMINISH WITH TIME, LIKELY IN THE 12-2 AM EDT TIME FRAME.  
WITHIN THIS BAND, A SOLID 1.5-2.5 INCHES OF RAINFALL IS EXPECTED.  
AREAS EAST OF THE BAND ACROSS FAR NORTH-CENTRAL KY HAVE REMAINED  
RAIN-FREE TODAY, SO THIS RAINFALL WILL BE WELCOMED AND WITH RATES  
DIMINISHING WITH TIME, GOOD GROUND ABSORPTION WILL BE POSSIBLE,  
EXCEPT IN THE URBAN AREAS.  
 
COLD OUTFLOW FROM THIS CONVECTION HAS PUSHED SOUTHWARD AND DOWN  
TOWARD THE WK/BG PARKWAY CORRIDOR. CURRENT EXPECTATIONS ARE FORE  
THIS CONVECTION TO MAINLY STAY ON THE INDIANA SIDE OF THE OHIO  
RIVER, THOUGH THE SOUTHWEST EDGE OF THE RAINFALL MAY MAKE IT INTO  
THE LOUISVILLE METRO REGION OVER THE NEXT 1-3 HOURS.  
 
 
   
SHORT TERM /THROUGH WEDNESDAY/  
 
ISSUED AT 241 PM EDT MON MAY 18 2026  
 
CURRENT MESOANALYSIS SHOWS 2000-2500 J/KG OF UNINHIBITED SBCAPE,  
ABOUT 20KTS OF DEEP LAYER SHEAR, AND STEEP LAPSE RATES. NOT SEEING  
MUCH AGITATED CU OVER OUR CWA JUST YET, BUT JUST TO THE WEST, WE  
HAVE SEEN SOME INITIATION. SHEAR WILL SLIGHTLY INCREASE AS THE MCS  
APPROACHES THE CWA, WHICH WILL HELP STORMS TO BECOME SLIGHTLY MORE  
ORGANIZED. OVER THE NEXT FEW HOURS DO EXPECT SOME SCATTERED STRONG  
TO SEVERE STORMS, WITH A WIND AND HAIL THREAT. THE THREAT AREA WILL  
BE SMALL, OVER SOUTHERN INDIANA AND JUST ALONG THE OHIO RIVER. MOST  
OF THE REGION WILL BE SPARED OF ANY STORMS. ADDITIONALLY, PWATS NEAR  
1.8-2.0 INCHES AND A SLOWLY MOVING LINE OF STORMS WILL ALLOW FOR  
HEAVY RAINFALL. THIS LINE IS ALSO MOVING APRALLEL TO THE LLJ, WHICH  
WILL ALLOW FOR TRAINING. DUE TO THIS, THERE IS ALSO A RISK FOR HEAVY  
RAINFALL TO LEAD TO SOME MINOR FLOODING ISSUES OVER OUR FAR  
NORTHWESTERN AREAS IN SOUTHERN INDIANA.  
 
AS THE SUN SETS, WE WILL QUICKLY LOSE INSTABILITY. SHOWERS AND  
STORMS ARE EXPECTED TO QUICKLY DISSIPATE. WITH BROKEN SKY COVER AND  
LIGHT SOUTHERLY WINDS, NOT EXPECTING A GREAT RADIATIONAL COOLING  
NIGHT. LOW TEMPERATURES WILL LIKELY REMAIN WARM IN THE UPPER 60S AND  
LOW 70S. THIS WILL BE CLOSE TO WARM MINIMUM RECORDS FOR MAY 18.  
 
AHEAD OF AN APPROACHING COLD FRONT, WAA WILL CONTINUE TO KEEP  
TEMPERATURES IN THE UPPER 80S AND BRUSHING 90. THIS WILL HELP SBCAPE  
TO INCREASE NEAR 3000J/KG. DEW POINTS WILL ALSO CREEP INTO THE UPPER  
60S AND LOW 70S. THOUGH SHEAR WILL REMAIN LOW AROUND 20KTS. PULSE  
SUMMERTIME THUNDERSTORMS WILL BE POSSIBLE IN THE AFTERNOON PRIOR TO  
THE COLD FRONT AND ASSOCIATION LINE OF STORMS. WHEN THE COLD FRONT  
APPROACHES, WE ARE EXPECTING A DECAYING LINE OF STORMS TO OUTRUN THE  
BEST FORCING ALONG THE COLD FRONT. WIND AND HAIL WILL BE THE MAIN  
THREAT ON TUESDAY OVER THE NORTHWESTERN 2/3RD OF THE CWA. THE COLD  
FRONT WILL BEGIN TO SLOW ITS PROGRESSION SOUTHWARD TUESDAY NIGHT,  
MAKING IT THROUGH MOST OF THE CWA BY WEDNESDAY MORNING.  
 
 
   
LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/  
 
ISSUED AT 241 PM EDT MON MAY 18 2026  
 
AS THE COLD FRONT SLOWLY SAGS THE THE SOUTH ON WEDNESDAY, WIDESPREAD  
SHOWERS AND SCATTERED THUNDERSTORMS ARE EXPECTED, ESPECIALLY FOR THE  
SOUTHERN HALF OF OUR AREA. RICH MOISTURE ALONG THE FRONT WILL HELP  
FUEL THESE SHOWERS AND STORMS, WITH LREF PW VALUES RANGING FROM 1.4-  
1.7" (>95TH PERCENTILE CLIMATOLOGICALLY). INSTABILITY TO THE SOUTH  
OF THE FRONT WILL ALSO HELP FUEL THESE SHOWERS, WITH LREF MEAN  
SBCAPE AROUND 750-1000 J/KG. THE WIND SHEAR PROFILE IS VERY MEAGER,  
SO WE DON'T CURRENTLY EXPECT SEVERE WEATHER AT THIS STAGE. WITH THE  
FRONT MOVING THROUGH, TEMPERATURES WILL MUCH CLOSER TO NORMAL FOR  
THIS TIME OF YEAR, WITH HIGHS IN THE MID-TO-UPPER 70S NORTH OF THE  
FRONT IN SOUTHERN INDIANA AND NORTHERN KENTUCKY, AND HIGHS IN THE  
LOW 80S SOUTH OF THE FRONT IN SOUTH CENTRAL KENTUCKY.  
 
THE FRONT STALLS OUT JUST SOUTH OF OUR AREA BY THURSDAY, BUT WITH  
SOME MOISTURE STILL IN PLACE OVER OUR FAR SOUTHERN COUNTIES CHANCES  
FOR SHOWERS WILL BE POSSIBLE (35-50%). WITH NORTHERLY FLOW AT THE  
SURFACE, TEMPERATURES ACROSS THE REGION WILL BE SLIGHTLY COOLER THAN  
WEDNESDAY, WITH HIGHS IN THE LOW-TO-MID 70S.  
 
THOUGH AN AREA OF SURFACE HIGH PRESSURE TRIES TO BUILD IN OVER THE  
GREAT LAKES AND OHIO VALLEY REGIONS THURSDAY, A BROAD UPPER LEVEL  
TROUGH OVER THE WESTERN CONUS PUSHES EASTWARD AND DRIVES THE HIGH  
OUT OF THE AREA. AHEAD OF THE TROUGH AXIS, A SERIES OF SHORTWAVES  
SURGES NORTHEASTWARD, LIFTING THE FRONTAL BOUNDARY NORTHWARD THURSDAY  
NIGHT. CONSIDERABLE SOUTHERLY FLOW AT THE SURFACE AND ALOFT WILL  
ALLOW DEEP MOISTURE TO SURGE BACK NORTHWARD, HELPING SET UP A FEW  
DECENT PERIODS OF SHOWERS AND SOME THUNDERSTORMS INTO MEMORIAL DAY  
WEEKEND. THE SOUTHERLY FLOW WILL ALSO ALLOW TEMPERATURES TO RISE  
BACK UP INTO THE 80S BY THE WEEKEND, BUT WITH DEW POINTS AGAIN IN  
THE MID 60S, IT WILL ALSO FEEL RATHER MUGGY OUTSIDE. THE MORE  
ACTIVE PATTERN FOR ROUNDS OF SHOWERS IS CURRENTLY EXPECTED TO LAST  
THROUGH THE END OF THE FORECAST PERIOD, SO A LITTLE BIT OF DROUGHT  
RELIEF MAY FINALLY BE ON THE WAY.  
 
 
   
AVIATION /06Z TAFS THROUGH 12Z WEDNESDAY/  
 
ISSUED AT 112 AM EDT TUE MAY 19 2026  
 
EARLIER CONVECTION OVER SOUTHERN INDIANA HAS CONTINUED TO WIND DOWN  
EARLY THIS MORNING. FOR THE OVERNIGHT PERIOD, VFR CONDITIONS ARE  
EXPECTED ACROSS THE REGION. WINDS WILL GENERALLY BE OUT OF THE  
NORTHEAST, BUT WILL VEER AROUND TO THE SOUTHEAST AND EVENTUALLY TO  
THE SOUTH TOWARD DAWN. FOR THE DAYTIME HOURS, A COLD FRONT WILL  
APPROACH THE REGION FROM THE WEST. AHEAD OF THIS FEATURE, GUSTY  
SOUTHWEST WINDS WILL BE SEEN ACROSS THE REGION. SOUTHWEST WINDS OF  
10-15KTS WITH GUSTS OF 20-24KTS ARE EXPECTED FROM ROUGHLY 19/14-  
19/23Z. SCATTERED CONVECTION MAY MOVE INTO THE WESTERN PORTIONS OF  
THE AREA AFTER 20/00Z. FOR THIS REASON, WILL KEEP THE PROB30'S  
GOING AT THE END OF THE PERIOD.  
 
 
   
LMK WATCHES/WARNINGS/ADVISORIES  
 
KY...NONE.  
IN...NONE.  
 
 
 
 
 
MESOSCALE....MJ  
SHORT TERM...SRW  
LONG TERM....BEN  
AVIATION.....MJ  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab KY Page
The Nexlab IN Page
Main Text Page