111  
FXUS63 KLMK 161750  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
150 PM EDT WED SEP 16 2026  
   
KEY MESSAGES
 
 
* HEAT ADVISORY REMAINS IN EFFECT UNTIL THURSDAY EVENING.  
 
* UNSEASONABLY HOT TEMPERATURES CONTINUES WITH HIGHS IN THE MID TO  
UPPER 90S AND HEAT INDEX VALUES BETWEEN 100-105.  
 
* WEAK SFC BOUNDARY BRINGS LOW END (20-30%) RAIN CHANCES FOR FRIDAY  
 
* WHILE NOT AS HOT, TEMPERATURES IN THE LOW TO MID 90S EXPECTED FOR  
THE WEEKEND.  
 

 
   
SHORT TERM /THROUGH THURSDAY/
 
 
ISSUED AT 150 PM EDT WED SEP 16 2026  
 
HEAT ADVISORY REMAINS IN EFFECT UNTIL THURSDAY EVENING THANKS TO THE  
STRONG ANOMALOUS 600DM UPPER-LEVEL RIDGE. AS OF EARLY AFTERNOON  
TEMPERATURES WERE ALREADY IN OR JUST AROUND 90 WITH HEAT INDEX  
VALUES NEAR 100 DEGREES. THE ONLY POTENTIAL IMPACT IN THE WEATHER  
OUTSIDE OF THE HEAT IS A STALLED SFC BOUNDARY ACROSS NORTHERN IN,  
NORTH IF THE I-70 CORRIDOR. RADAR WAS SHOWING A FEW ISOLATED CELLS  
FORMING ACROSS CENTRAL IN THIS AFTERNOON, WHILE THE CHANCE OF AN  
ISOLATED SHOWER CAN'T BE RULED OUT, GIVEN HOW FAR NORTH THE MAIN  
BOUNDARY IS TO THE CWA, OVERALL CONFIDENCE IN PRECIPITATION IS  
RATHER LOW.  
 
IT WILL REMAIN MOSTLY CLEAR OVERNIGHT WITH TEMPERATURES STAYING WARM  
AND BOTTOMING OUT IN LOW 70S WITH URBAN LOCATIONS SEEING LOWS IN THE  
MID 70S WITH LIGHT WINDS PROVIDING VERY LITTLE RELIEF FROM THE  
OVERALL HEAT. BY TOMMOROW, THE UPPER RIDGE CONTINUES ITS INFLUENCE  
OVER THE REGION AS IT SHIFTS SLIGHTLY WESTWARD. THE STALLED BOUNDARY  
ACROSS NORTHERN IN LIFTS NORTHWARD ALLOWING FOR TEMPERATURES TO ONCE  
AGAIN HEAT BACK INTO THE MID TO UPPER 90S WITH HEAT INDEX VALUES  
BETWEEN 100-105.  
 

 
   
LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/
 
 
ISSUED AT 150 PM EDT WED SEP 16 2026  
 
STALLED SFC BOUNDARY WILL DRIFT SOUTHWARD TOWARDS THE OHIO VALLEY  
AND THE COMMONWEALTH THURSDAY NIGHT INTO FRIDAY MORNING. THIS WILL  
INCREASE SHOWER/STORM CHANCES ACROSS THE CWA ESPECIALLY OVER  
SOUTHERN IN, NORTH CENTRAL KY AND OVER THE BLUEGRASS REGION. CURRENT  
FORECASTS CONTINUES TO SHOW A 20-30 PERCENT CHANCE OF POPS. THERE  
REMAINS SOME UNCERTAINTY ON HOW FAR SOUTH THIS BOUNDARY WILL GO  
ACROSS THE STATE OF KY. THE PLACEMENT OF THIS BOUNDARY WILL HAVE A  
LARGE INFLUENCE ON NOT JUST POTENTIAL SHOWER AND STORM POTENTIAL BUT  
ALSO ON OUR TEMPERATURES. THE IS SOME GUIDANCE THAT IS STARTING TO  
SUGGEST THE BOUNDARY COULD GO AS FAR SOUTH AS THE KY/TN BORDER. IF  
THIS SCENARIO PLAYS OUT WE WOULD NOT NEED TO CONTINUE THE HEAT  
ADVISORY INTO FRIDAY. IF IT STOPS SHORT AND MAKES IT TO ONLY CENTRAL  
KY THEN SOME OF OUR COUNTIES TO THE SOUTH AND WEST MAY NEED TO  
CONTINUE THE HEAT ADVISORY FOR ANOTHER DAY. GIVEN THE LACK OF  
CONFIDENCE, IT WAS DECIDED TO WAIT ON MORE DATA AND CONFIDENCE  
BEFORE EXTENDING THE CURRENT HEAT ADVISORY FOR FRIDAY.  
 
FRONT WILL LIFT NORTH AGAIN TO START THE WEEKEND BUT THE CENTER OF  
THE UPPER RIDGE WILL BE FURTHER WEST. WHILE WE WILL SEE TEMPERATURES  
BOTH SATURDAY AND SUNDAY RETURN TO THE LOW-MID 90S, HEAT INDEX  
VALUES WILL NOT BE AS HOT. THE FORECAST CONTINUES TO LOOK MAINLY DRY  
FOR THE WEEKEND.  
 
PATTERN FLATTENS OUT AND BECOMES MORE ZONAL FOR EARLY NEXT WEEK WITH  
A SERIES OF SYSTEMS WORKING THROUGH THE REGION WITH A COLD FRONT  
PUSHING THROUGH DURING THE FIRST HALF OF THE WEEK. THIS SHOULD BRING  
COOLER TEMPERATURES IN THE 80S BY THE MIDDLE OF NEXT WEEK WITH SOME  
SHOWERS AND POSSIBLE STORMS.  
 

 
   
AVIATION /12Z TAFS THROUGH 18Z THURSDAY/
 
 
ISSUED AT 1146 AM EDT WED SEP 16 2026  
 
VFR FLIGHT CATEGORIES REMAIN THROUGH THE FORECAST PERIOD THANKS TO  
STRONG ANOMALOUS 600CM UPPER RIDGE AND SFC HIGH PRESSURE. SFC  
BOUNDARY IS TO THE NORTH OVER INDIANA. SOME MID-LEVEL CU LIKELY WILL  
DEVELOP IN THE AFTERNOON AND WHILE THERE IS A VERY SMALL CHANCE OF  
AN ISOLATED SHOWER/STORM (LESS THAN 10%) MOST TERMINALS SHOULD  
REMAIN DRY. THIS WILL CONTINUE GOING INTO THE OVERNIGHT.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...HEAT ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THURSDAY FOR  
KYZ023>034-038-045-046-053-054-061>065-070>077-081.  
IN...HEAT ADVISORY UNTIL 8 PM EDT /7 PM CDT/ THURSDAY FOR  
INZ076>079-083-084-089>092.  
 

 
 

 
 
SHORT TERM...BTN  
LONG TERM...BTN  
AVIATION...BTN  
 
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