364  
FXUS63 KLMK 071729  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
129 PM EDT MON SEP 7 2026  
   
..UPDATED AVIATION DISCUSSION  
 
   
KEY MESSAGES  
 
* DRY AND SEASONABLE LABOR DAY EXPECTED WITH ONLY A SMALL CHANCE OF  
A SHOWER OR STORM AROUND THE LAKE CUMBERLAND REGION BY EARLY  
EVENING.  
 
* THE HOTTEST DAY OF THE WEEK WILL BE WEDNESDAY WITH HIGHS IN THE  
LOW TO MID 90S AND PEAK HEAT INDICES IN THE LOW 100S WEST OF I-65.  
 
* A COLD FRONT ARRIVES THURSDAY MORNING WITH 70-80% CHANCE OF  
SHOWERS AND A FEW STORMS POSSIBLE. FAIRLY WIDESPREAD RAINFALL  
AMOUNTS BETWEEN .25" AND .5" ARE CURRENTLY EXPECTED.  
 
 
   
SHORT TERM /THROUGH TUESDAY NIGHT/  
 
ISSUED AT 241 AM EDT MON SEP 7 2026  
 
THINGS ARE QUIET ACROSS THE REGION AT THIS HOUR WITH HIGH PRESSURE  
CENTERED OVER THE EASTERN GREAT LAKES, EXTENDING INFLUENCE INTO OUR  
AREA. LIGHT NE SURFACE WINDS AND A FEW UPPER CLOUDS WILL CONTINUE  
THIS MORNING. THIS WILL ALLOW FOR LOWS MOSTLY IN THE LOW AND MID 60S  
TOWARD SUNRISE, ALTHOUGH CAN'T RULE OUT A FEW UPPER 50S ACROSS OUR  
FAR NE. LIGHT TO STEADY NE/ENE WINDS CONTINUE TODAY WITH PLENTY OF  
SUNSHINE TO GO ALONG WITH A FEW MID AND UPPER CLOUDS AT TIMES. TEMPS  
SHOULD BE A TICK OR TWO WARMER THAN YESTERDAY WITH MAX VALUES MOSTLY  
IN THE 85 TO 90 DEGREE RANGE.  
 
ALMOST ALL OF THE AREA STAYS DRY TODAY, ALTHOUGH WILL HAVE TO  
CONTINUE MENTION OF SOME ISOLATED TO WIDELY SCATTERED SHOWER OR  
STORM CHANCES DOWN NEAR THE LAKE CUMBERLAND REGION THIS EVENING.  
INVERTED SURFACE TROUGH LOOKS TO SET UP WITH DEW POINTS IN THE UPPER  
60S TO NEAR 70 POOLING IN OUR FAR SE. THIS ADDED LOW LEVEL MOISTURE  
WILL AID THE DEVELOPMENT OF A MODEST INSTABILITY AXIS ON THE ORDER  
OF 500-750 J/KG OF ML CAPE, AND COULD PROVIDE ENOUGH FUEL FOR A FEW  
SHOWERS AND STORMS ASSUMING THE WEAK SURFACE CONVERGENCE IS ENOUGH  
OF A TRIGGER. HI-RES CAMS AND OTHER DETERMINISTIC DATA SUGGESTS THAT  
AT LEAST A FEW SHOWERS OR STORMS WILL DEVELOP BY EARLY EVENING.  
OVERALL, DEEP LAYER SHEAR IS WEAK SO ANY STORMS WOULD BE PULSE IN  
NATURE.  
 
OTHER THAN THAT, DRY CONDITIONS CONTINUE THROUGH EARLY WEEK WITH  
UPPER RIDGING STRENGTHENING OVER THE SOUTHERN CONUS. THIS WILL ALLOW  
TEMPERATURES TO CONTINUE TRENDING UPWARD AS WE MOVE THROUGH TUESDAY.  
ANOTHER COUPLE DEGREE RISE BY THEN WILL ALLOW FOR HIGHS IN THE UPPER  
80S TO LOW 90S ACROSS THE AREA.  
 
 
   
LONG TERM /WEDNESDAY THROUGH SUNDAY/  
 
ISSUED AT 241 AM EDT MON SEP 7 2026  
 
WEDNESDAY - THURSDAY NIGHT...  
 
THE HOTTEST DAY OF THE WEEK LOOKS TO BE WEDNESDAY AS UPPER RIDGING  
CONTINUES TO DOMINATE THE SOUTHERN HALF OF THE CONUS. MEANWHILE, A  
STEADY SW SURFACE FLOW WILL SET UP OVER OUR REGION BETWEEN HIGH  
PRESSURE CENTERED OFF THE MID ATLANTIC COAST, AND A STRONG SURFACE  
LOW OVER EASTERN CANADA. IN FACT, THE PRESSURE GRADIENT WILL BE  
QUITE IMPRESSIVE FOR THIS TIME OF YEAR, AND LOOKS LIKE WE COULD SEE  
SOME 20-25 MPH GUSTS FROM A VERY WELL MIXED BOUNDARY LAYER. THIS  
LOOKS LIKE A PATTERN WHERE TEMPS COULD OVERACHIEVE, SO LIKE WHERE  
THE NBM IS TOWARD THE HIGHER SIDE OF THE GUIDANCE ENVELOPE, AND  
SIMILAR TO THE 90TH PERCENTILE ECM TEMP GUIDANCE. PEAK HEAT INDICES  
COULD BE A BIT OF A CONCERN FOR WEDNESDAY AS THEY WILL LIKELY REACH  
INTO THE LOW 100S FOR A TIME. EXPECT AFTERNOON MIXING MAY LOWER DEW  
POINTS ENOUGH THROUGH THE AFTERNOON TO KEEP ANY HEAT ADVISORY  
HEADLINES FROM BEING NEEDED, BUT IT WILL BE CLOSE. OVERALL, LOW TO  
MID 90S EXPECTED FOR HIGHS, WITH SHOWER AND STORM CHANCES HOLDING  
OFF UNTIL LATER WEDNESDAY NIGHT INTO THURSDAY.  
 
A COLD FRONT TRAILING FROM THE AFOREMENTIONED STRONG EASTERN CANADA  
SURFACE LOW WILL APPROACH FOR THURSDAY. AHEAD OF THIS FEATURE,  
FAIRLY WIDESPREAD COVERAGE OF SHOWERS AND STORMS IS ANTICIPATED TO  
DROP INTO AND THROUGH OUR REGION. LOOKS TO BE A FAIRLY STRONG AMOUNT  
OF DEEP LAYER SHEAR ACROSS THE NORTHERN HALF OF OUR CWA WHERE 35-45  
KNOTS MAY BE REALIZED. ACROSS SOUTHERN KY, VALUES WOULD BE WEAKER  
AND MORE IN THE 25-35 KNOT RANGE. WEAK TO MODEST INSTABILITY AND  
PARTICULARLY WEAK MID LEVEL LAPSE RATES COULD BE THE LIMITING FACTOR  
FOR WHETHER ANY STRONG TO SEVERE STORMS WILL BE POSSIBLE, AND TIMING  
OF THE FRONTAL PASSAGE ON THURSDAY WILL HAVE A LOT TO DO WITH THAT.  
SHOULD FAIRLY STRONG STORMS DEVELOP, THEN WE MAY HAVE TO WATCH FOR A  
BIT OF TRAINING AS THE DEEP LAYER FLOW WILL BE NEARLY PARALLEL TO  
THE SURFACE BOUNDARY. A FEW LOCALIZED AREAS COULD SEE SOME HIGHER  
RAIN TOTALS IN THIS SETUP, BUT OVERALL THE EXPECTED WIDESPREAD  
RAINFALL BETWEEN .25" AND .5" FOR MOST WILL BE WELCOME. RIGHT NOW,  
LREF PROBABILITIES OF 1" OR MORE DROP OFF TO 10-15% OR LESS.  
 
FRIDAY - SUNDAY...  
 
THINGS ARE EXPECTED TO BE A BIT COOLER AND OVERALL DRIER BY FRIDAY  
AS HIGH PRESSURE BUILDS IN BEHIND THE COLD FRONT. PERHAPS A FEW  
SHOWERS LINGER ACROSS OUR SOUTHERN CWA, BUT WILL ONLY KEEP LOW  
CHANCES IN HERE. TEMPS SETTLE BACK INTO THE MID AND UPPER 80S TO END  
THE WEEK, AT LEAST BRIEFLY. THE OVERALL DRY PATTERN SHOULD CONTINUE  
INTO THE WEEKEND ALTHOUGH SOME WEAK TROUGHING MAY ALLOW FOR A FEW  
NON-ZERO SHOWER OR STORM CHANCES. BETTER CHANCES FOR THE UPPER RIDGE  
TO BUILD BACK IN BY LATE WEEKEND, AND THIS WILL ALLOW TEMPS TO RISE  
BACK INTO THE UPPER 80S AND LOW 90S IF IT OCCURS. ONLY LOW TO MEDIUM  
CONFIDENCE IN THE WEEKEND FOR NOW GIVEN SOME UNCERTAINTY IN HOW THE  
UPPER PATTERN WILL EVOLVE BY THIS TIME.  
 
 
   
AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/  
 
ISSUED AT 129 PM EDT MON SEP 7 2026  
 
VFR CONDITIONS ARE EXPECTED THROUGH THIS FORECAST PERIOD. HIGH  
PRESSURE WILL HELP TO KEEP WINDS LIGHT AND SKIES WITH A LIGHT CU  
FIELD. WINDS THIS AFTERNOON WILL VARY FROM THE NORTH-NORTHEAST TO  
THE EAST AROUND 4-9KTS. IN THE EVENING, WINDS WILL RELAX TO MOSTLY  
VARIABLE AROUND 3-4KTS. AROUND SUNRISE, WINDS WILL VEER TO THE SOUTH  
AROUND 7-10KTS.  
 
 
   
LMK WATCHES/WARNINGS/ADVISORIES  
 
KY...NONE.  
IN...NONE.  
 
 
 
 
 
SHORT TERM...BJS  
LONG TERM...BJS  
AVIATION...SRW  
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