178  
FXUS63 KLMK 160807  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
407 AM EDT FRI MAY 16 2025  
   
KEY MESSAGES  
 
* SIGNIFICANT SEVERE WEATHER OUTBREAK POSSIBLE LATE THIS AFTERNOON  
INTO THIS EVENING.  
 
* ALL SEVERE WEATHER HAZARDS ARE ON THE TABLE, INCLUDING DAMAGING  
WINDS, LARGE HAIL, TORNADOES, AND TORRENTIAL RAINFALL. A FEW  
STRONG TORNADOES AND INSTANCES OF VERY LARGE HAIL ARE POSSIBLE.  
 
* STRONG TO SEVERE THUNDERSTORMS ARE ALSO POSSIBLE THIS MORNING  
WEST OF INTERSTATE 65, WITH LARGE HAIL AS THE MAIN HAZARD.  
 
 
   
MESOSCALE  
 
ISSUED AT 336 AM EDT FRI MAY 16 2025  
 
BOUNDARY HAS LIT UP FROM THE SHAWNEE NATIONAL FOREST IN SOUTHERN  
ILLINOIS ENE TO NEAR HENDERSON, AND STORMS TAPPED INTO STRONG  
ELEVATED INSTABILITY TO PRODUCE VIGOROUS CORES ALOFT. GIVEN THE VERY  
UNSTABLE AND STRONGLY SHEARED ENVIRONMENT, AS STORMS CONTINUE TO  
DEVELOP THROUGH EARLY MORNING THEY WILL CARRY MAINLY A SVR HAIL  
THREAT FROM THE PENNYRILE INTO THE HOOSIER NATIONAL FOREST AND  
SECTIONS OF KENTUCKY WEST OF INTERSTATE 65. DAMAGING WINDS AND EVEN  
A TORNADO OR TWO CAN'T BE RULED OUT COMPLETELY, BUT STORMS WILL HAVE  
A REALLY DIFFICULT TIME BECOMING SFC BASED. CONFIDENCE IS ALSO  
SLIGHTLY DIMINISHED SOUTH OF THE WK PARKWAY BUT WE COULD SEE  
CONVECTION DOWN TOWARD BWG LATER IN THE MORNING.  
 
 
   
SHORT TERM /THROUGH TONIGHT/  
 
ISSUED AT 407 AM EDT FRI MAY 16 2025  
 
A SIGNIFICANT SEVERE WEATHER OUTBREAK IS POSSIBLE LATER THIS  
AFTERNOON AND THIS EVENING ACROSS THE OHIO VALLEY. STORMS DEVELOPING  
AHEAD OF AN INCOMING COLD FRONT WILL QUICKLY BECOME SEVERE IN A VERY  
UNSTABLE AND STRONGLY SHEARED ENVIRONMENT. ALL SEVERE WEATHER  
HAZARDS, INCLUDING WIDESPREAD DAMAGING WINDS, VERY LARGE HAIL, AND  
STRONG TORNADOES ARE POSSIBLE, AS WELL AS LOCALIZED FLASH FLOODING.  
 
MAIN BUST POTENTIAL HINGES ON THE EVOLUTION OF STORMS THIS MORNING,  
WHICH HAVE DEVELOPED OVER WESTERN KENTUCKY. THESE STORMS WILL HAVE A  
LARGE HAIL THREAT OF THEIR OWN, ESPECIALLY WEST OF INTERSTATE 65.  
WHILE THEY WILL AT LEAST TEMPORARILY STABILIZE THE ATMOSPHERE,  
STRONG WARM ADVECTION IS LIKELY TO WIN OUT, ALLOWING A FAIRLY QUICK  
RECOVERY THIS AFTERNOON.  
 
WITH AROUND 3000 J/KG OF MIXED-LAYER CAPE, 1000 J/KG OF DOWNDRAFT  
CAPE, AND 60 KT OF EFFECTIVE SHEAR, INITIALLY DISCRETE STORMS WILL  
ORGANIZE INTO AT LEAST BOWING SEGMENTS. A FEW OF THE DISCRETE CELLS  
COULD PRODUCE VERY LARGE HAIL AND/OR STRONG TORNADOES, AND LINE  
SEGMENTS COULD PRODUCE HURRICANE-FORCE WIND GUSTS. SPIN-UP TORNADOES  
WILL ALSO BE IN PLAY WITH ANY OF THE BOWING STRUCTURES AS WELL.  
 
THE PEAK SEVERE THREAT COULD BE SLIGHTLY DELAYED DEPENDING ON HOW  
QUICKLY THE ATMOSPHERE CAN RELOAD AFTER MORNING CONVECTION, BUT THE  
THREAT WILL MAINLY BE FOCUSED ON THE EVENING HOURS. INITIAL DISCRETE  
CELLS COULD DEVELOP IN THE LATE AFTERNOON.  
 
IT'S ALSO WORTH NOTING THAT IN THE LATE EVENING, THE LINE WILL  
BECOME MORE EAST-WEST ORIENTED, OPENING THE DOOR FOR EXCESSIVE  
RAINFALL ESPECIALLY OVER SOUTH-CENTRAL KENTUCKY. CONFIDENCE IN THE  
EXACT PLACEMENT IS LOW AT THIS TIME, BUT IT BEARS WATCHING AS THE  
EVENT UNFOLDS.  
 
BOTTOM LINE, SIGNIFICANT SEVERE WEATHER IS POSSIBLE LATE THIS  
AFTERNOON AND THIS EVENING. MAKE SURE YOU HAVE MULTIPLE WAYS TO  
RECEIVE WARNINGS AND A PLAN IN PLACE SHOULD A WARNING BE ISSUED!  
 
 
   
LONG TERM /SATURDAY THROUGH THURSDAY/  
 
ISSUED AT 352 PM EDT THU MAY 15 2025  
 
BY SATURDAY MORNING, THE ACTUAL COLD FRONT WILL BE PUSHING THROUGH  
THE AREA WITH MOST OF THE SHOWERS AND STORMS EXITING TO OUR EAST.  
THE ASSOCIATED UPPER LOW WILL BE OVER THE GREAT LAKES WITH THE  
LONGWAVE TROUGH AXIS EXTENDING SOUTH OVER THE OH AND TN VALLEYS  
BEFORE FLATTENING OUT AGAINST THE SUBTROPICAL RIDGE OVER THE GULF.  
WEAK CAA BEHIND THE FRONT WILL RESULT IN CLIMATOLOGICAL NORMAL  
TEMPERATURES FOR THE WEEKEND WITH HIGHS IN THE MID TO UPPER 70S TO  
LOWER 80S ACCOMPANIED BY BREEZY WSW WINDS ON SATURDAY. OVERALL, MOST  
WILL EXPERIENCE A FAIR WEATHER WEEKEND.  
 
SOUTHERN KY WILL SEE A SLIGHT CHANCE OF SHOWERS ON SUNDAY AS THE  
SOUTHERN EDGE OF THE NEW AIRMASS BEGINS TO LIFT NORTHWARD DUE TO THE  
NEXT LOW PRESSURE SYSTEM STRENGTHENING OVER THE CENTRAL PLAINS. THIS  
WILL BEGIN ANOTHER PERIOD OF UNSETTLED WEATHER AS WE ENTER THE  
BEGINNING OF THE NEW WORK WEEK.  
 
BY MONDAY, A WARM FRONT WILL BEGIN LIFTING ACROSS THE REGION  
RESULTING IN WARM AND MOIST AIR ADVECTION, AS PWATS SURGE INTO THE  
UPPER PERCENTILES OF SPC'S SOUNDING CLIMATOLOGY. MODELS TEND TO  
AGREE ON CONVECTION FROM OUR WEST MOVING INTO OUR AREA BY MONDAY  
MORNING WITH ANOTHER ROUND MONDAY EVENING. THE WARM FRONT APPEARS TO  
STALL OVER THE REGION, PROLONGING OUR SHOWER AND STORM CHANCES INTO  
TUESDAY AND WEDNESDAY BEFORE THE OCCLUDED LOW PUSHES THROUGH ON  
WEDNESDAY. WITH MODEL SOUNDINGS ADVERTISING SUFFICIENT INSTABILITY  
AND ML GUIDANCE ALSO SHOWING ENHANCED SEVERE PROBABILITIES, SEVERE  
WEATHER CAN NOT BE RULED OUT. DETAILS REMAIN HAZY THIS FAR OUT, BUT  
WILL CONTINUE TO MONITOR CLOSELY WITH SUBSEQUENT FORECAST PACKAGES.  
STAY TUNED.  
 
 
   
AVIATION /06Z TAFS THROUGH 12Z SATURDAY/  
 
ISSUED AT 137 AM EDT FRI MAY 16 2025  
 
MAIN CHALLENGE IN THIS TAF SET IS TIMING AND IMPACTS OF TWO  
DIFFERENT POTENTIAL WAVES OF CONVECTION. LOW-CONFIDENCE FORECAST  
OVERNIGHT AS HI-RES MODELS SHOW NEW DEVELOPMENT AFTER ~08Z.  
CONSENSUS TIMING ON A MORNING WAVE WOULD BE STARTING 10-12Z FOR THE  
TERMINALS BUT COULD EASILY BE FOCUSED JUST IN THE NORTH ON SDF AND  
LEX OR JUST SOUTH IN BWG. WILL CARRY A PERIOD OF SHRA FOR NOW  
WITHOUT ANY SIGNIFICANT RESTRICTIONS IN CIG/VIS.  
 
GUSTY SSW WINDS THROUGH THE AFTERNOON, AND THEN ANOTHER WAVE OF  
STORMS COMES IN STARTING AROUND 00Z, MAINLY FOR SDF AND LEX. HANDLED  
THOSE WITH TEMPO FOR IFR VIS AND GUSTY WINDS IN THE STRONGER STORMS.  
THE EVENING STORMS COULD PRODUCE SIGNIFICANT SEVERE WIND GUSTS, BUT  
THIS WILL BE MODULATED BY THE BEHAVIOR OF MORNING STORMS, SO WILL  
NOT HIT THAT TOO HARD JUST YET.  
 
 
   
LMK WATCHES/WARNINGS/ADVISORIES  
 
KY...NONE.  
IN...NONE.  
 
 
 
 
 
MESOSCALE...RAS  
SHORT TERM...RAS  
LONG TERM...CG  
AVIATION...RAS  
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