532  
FXUS63 KLMK 201057  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
657 AM EDT MON OCT 20 2025  
   
..UPDATED AVIATION DISCUSSION  
 
   
KEY MESSAGES  
 
* DRIER AND COOLER WEATHER IS EXPECTED FOR MUCH OF THE UPCOMING  
WEEK.  
 
* ANOTHER COLD FRONT WILL BRING A SMALL CHANCE FOR A SHOWER LATE  
TONIGHT INTO TUESDAY MORNING. BREEZY WEST WINDS ARE EXPECTED  
TUESDAY AND WEDNESDAY.  
 
* WIDESPREAD FROST LOOKS INCREASINGLY LIKELY THURSDAY MORNING AND  
FRIDAY MORNING.  
 
* UNSETTLED WEATHER IS LIKELY TO RETURN BY THE WEEKEND.  
 
 
   
SHORT TERM /THROUGH TONIGHT/  
 
ISSUED AT 350 AM EDT MON OCT 20 2025  
 
EARLY THIS MORNING, SATELLITE IMAGERY REVEALS CLEAR SKIES ACROSS THE  
LOWER AND MIDDLE OHIO VALLEY. RIVER VALLEY FOG IS NOTED OVER MUCH OF  
EASTERN KY, INCLUDING IN THE CUMBERLAND AND PORTIONS OF THE KENTUCKY  
RIVER VALLEY. LATEST RAP SFC ANALYSIS SHOWS HIGH PRESSURE CENTERED  
OVER THE TENNESSEE VALLEY AS THE PRESSURE GRADIENT HAS WEAKENED  
CONSIDERABLY SINCE YESTERDAY AFTERNOON. LIGHT WEST-SOUTHWEST WINDS  
HAVE BEEN OBSERVED, ALLOWING TEMPERATURES TO COOL INTO THE UPPER 30S  
AND LOW-TO-MID 40S. THROUGH SUNRISE, NO SIGNIFICANT WEATHER IS  
EXPECTED ASIDE FROM ONGOING RIVER VALLEY FOG. TEMPERATURES SHOULD  
SETTLE INTO THE UPPER 30S AND LOW 40S AROUND SUNRISE.  
 
TODAY, FAIRLY FLAT UPPER RIDGING WILL QUICKLY SLIDE ACROSS THE  
REGION AS ANOTHER TROUGH DESCENDS ACROSS THE CENTRAL CONUS. SUNNY  
SKIES ARE EXPECTED, WHICH WILL HELP TEMPERATURES WARM AFTER A CHILLY  
START THIS MORNING. ALSO ASSISTING TEMPERATURES WILL BE WARM  
ADVECTION AS SFC WINDS SHOULD BECOME SOUTH-SOUTHWESTERLY AND  
INCREASE IN STRENGTH LATER TODAY AS HIGH PRESSURE SLIDES OFF THE  
SOUTHEAST US COAST. HIGH TEMPERATURES SHOULD RANGE FROM THE MID 60S  
ACROSS THE BLUEGRASS REGION TO THE LOW 70S ALONG AND SW OF I-165.  
 
TONIGHT, A SFC COLD FRONT ASSOCIATED WITH A LEADING UPPER SHORTWAVE  
AMIDST BROADER UPPER TROUGHING WILL MOVE ACROSS THE MISSISSIPPI  
VALLEY AND INTO THE OHIO VALLEY. A STRENGTHENING HEIGHT GRADIENT  
ALOFT SHOULD SUPPORT THE DEVELOPMENT OF A 50 KT LLJ OVERNIGHT;  
HOWEVER, THE MOISTURE ADVECTION WITH THIS JET WILL BE MUCH LESS THAN  
THE PREVIOUS SYSTEM, WITH PW VALUES ONLY RISING TO AROUND 0.8-1"  
IMMEDIATELY AHEAD OF THE FRONT. AS A RESULT, HI-RES GUIDANCE SHOWS  
MOST AREAS REMAINING DRY EVEN WITH FROPA EARLY TUESDAY MORNING.  
HOWEVER, WE'LL ADVERTISE A SLIGHT CHANCE POP FOR AN ISOLATED  
SHOWERS, MAINLY ACROSS SOUTHERN IN AND THE BLUEGRASS REGION. WITH  
SOUTHERLY WINDS STAYING UP OVERNIGHT AHEAD OF THE FRONT,  
TEMPERATURES WILL BE MILDER TONIGHT, WITH LOWS ONLY FALLING INTO THE  
MID-TO-UPPER 40S AND LOW 50S.  
 
 
   
LONG TERM /TUESDAY THROUGH SUNDAY/  
 
ISSUED AT 350 AM EDT MON OCT 20 2025  
 
TUESDAY THROUGH THURSDAY NIGHT...  
 
DURING THE DAY ON TUESDAY, AN ANOMALOUS UPPER LOW WILL BE SETTLING  
ACROSS THE GREAT LAKES. THE INITIAL SFC COLD FRONT ASSOCIATED WITH  
THE UPPER LOW WILL BE MOVING ACROSS THE AREA AT THE BEGINNING OF THE  
PERIOD. BEHIND THE FRONT, A SETUP TYPICAL OF OCCLUDING SYSTEMS WILL  
BE PRESENT OVER THE OHIO VALLEY, WITH SEVERAL SMALLER PRESSURE  
TROUGHS SLIDING ACROSS THE REGION TUESDAY INTO TUESDAY NIGHT. A  
STRONG PRESSURE GRADIENT WILL SUPPORT BREEZY CONDITIONS THROUGH THE  
DAY ON TUESDAY, AND STEEP LOW-LEVEL LAPSE RATES IN THE POST-FRONTAL  
AIR MASS SHOULD HELP STRONGER WINDS ALOFT GET DOWN TO THE SFC.  
SUSTAINED WEST WINDS OF 10-20 MPH WITH GUSTS OF 20-30 MPH ARE  
EXPECTED ON TUESDAY. WHILE THE BEST CHANCE FOR A SHOWER WILL BE WITH  
THE INITIAL COLD FRONT EARLY TUESDAY MORNING, A STRAY SHOWER WILL BE  
POSSIBLE ALONG ACROSS THE NORTHERN HALF OF THE FORECAST AREA THROUGH  
THE DAY ON TUESDAY, THOUGH MOST WILL REMAIN DRY. HIGHS SHOULD RANGE  
FROM THE MID-TO-UPPER 60S ACROSS NORTHERN KY AND SOUTHERN IN TO  
AROUND 70 IN SOUTHERN KY.  
 
TUESDAY NIGHT INTO WEDNESDAY, THE UPPER LOW WILL PIVOT OVER THE  
GREAT LAKES, WITH CYCLONIC FLOW ALOFT GRADUALLY TRANSITIONING TO NW  
FLOW. COLD ADVECTION WILL CONTINUE DURING THIS PERIOD, THOUGH  
PERSISTENT WINDS TUESDAY NIGHT WILL LIKELY LIMIT RADIATIONAL  
COOLING. LOWS SHOULD FALL INTO THE UPPER 30S AND LOW-TO-MID 40S  
WEDNESDAY MORNING. BREEZY CONDITIONS WILL CONTINUE INTO THE DAY ON  
WEDNESDAY, AND THE PROXIMITY OF THE H85 THERMAL TROUGH SHOULD RESULT  
IN THE COOLEST HIGH TEMPERATURES OF THE WEEK. HIGHS SHOULD RANGE  
FROM THE UPPER 50S ACROSS SOUTHERN IN AND NORTHERN KY TO THE MID 60S  
ACROSS SOUTHERN KY.  
 
THE UPPER TROUGH WILL VERY GRADUALLY LIFT TO THE NE WEDNESDAY NIGHT  
INTO THURSDAY, WITH HIGH PRESSURE MOVING INTO THE TN VALLEY BY  
THURSDAY MORNING. THIS WILL ALLOW WINDS TO RELAX AND TEMPERATURES TO  
TUMBLE, WITH LOWS THURSDAY MORNING FALLING INTO THE MID-TO-UPPER 30S  
IN MOST LOCATIONS, THOUGH THE TYPICAL WARM SPOTS MAY STAY IN THE LOW  
40S. AFTER ANOTHER COOL AND DRY DAY ON THURSDAY WITH TEMPERATURES  
ONLY A FEW DEGREES WARMER THAN WEDNESDAY, THURSDAY NIGHT MAY FEATURE  
SOME OF THE COLDEST TEMPERATURES IN THE NEXT 7 DAYS, PARTICULARLY  
ACROSS THE NORTHEASTERN HALF OF THE FORECAST AREA. WIDESPREAD MID-TO-  
UPPER 30S ARE EXPECTED FRIDAY MORNING, WITH A FEW OF THE COOLER  
SPOTS ACROSS THE BLUEGRASS AND SOUTHERN IN LIKELY MAKING A RUN AT  
FREEZING. THIS WOULD SUPPORT ANOTHER CHANCE FOR WIDESPREAD FROST.  
 
FRIDAY THROUGH NEXT WEEKEND...  
 
FOR FRIDAY INTO NEXT WEEKEND, THE MAIN FOCUS WILL BE ON A CUTOFF LOW  
WHICH IS EXPECTED TO EJECT FROM THE FOUR CORNERS REGION ACROSS THE  
SOUTHERN PLAINS AND INTO THE OHIO VALLEY. AHEAD OF THIS SYSTEM,  
SOUTHERLY FLOW WILL TAP INTO GULF MOISTURE, WITH AN AXIS OF WATER  
VAPOR TRANSPORT EXTENDING INTO THE OHIO VALLEY. OVER THE PAST FEW  
MODEL RUNS, THIS SYSTEM HAS TRENDED SLOWER IN ITS EASTWARD  
PROGRESSION, MAKING IT MORE LIKELY THAT FRIDAY REMAINS DRY OVER OUR  
AREA, WITH HIGH CLOUDS INCREASING DURING THE PERIOD.  
 
PRECIPITATION CHANCES WILL INCREASE FRIDAY NIGHT INTO THE DAY ON  
SATURDAY, WITH CONFIDENCE INCREASING IN OFF AND ON PERIODS OF RAIN  
NEXT WEEKEND. AT THIS TIME, MODEST FORCING AND MOISTURE WILL SUPPORT  
MODEST PRECIPITATION AMOUNTS, WITH MOST LIKELY QPF RANGING FROM 0.25-  
1". HOWEVER, HIGH-END ENSEMBLE AMOUNTS OF 2-3" ARE NOTED, SO THERE  
IS AN OUTSIDE CHANCE FOR MORE SIGNIFICANT RAINFALL. WITH CLOUDS AND  
RAIN LINGERING OVER THE REGION THROUGH THE WEEKEND, DIURNAL  
TEMPERATURE RANGES WILL BE SUPPRESSED, WITH HIGHS GENERALLY IN THE  
60S AND LOWS IN THE UPPER 40S AND 50S.  
 
 
   
AVIATION /12Z TAFS THROUGH 18Z TUESDAY/  
 
ISSUED AT 656 AM EDT MON OCT 20 2025  
 
VFR CONDITIONS AND SOUTH-SOUTHWEST WINDS ARE EXPECTED THROUGH THE  
DAYTIME HOURS TODAY, WITH WIND SPEEDS INCREASING LATER THIS MORNING  
TO AROUND 10 KT FOR THE LATE MORNING AND EARLY-TO-MID MORNING HOURS.  
A FEW 15-20 KT GUSTS WILL BE POSSIBLE THIS AFTERNOON, ESPECIALLY AT  
HNB. TONIGHT, A COLD FRONT WILL APPROACH THE REGION, MOVING THROUGH  
BETWEEN 08-13Z TUESDAY. A 50 KT SOUTHWESTERLY LLJ WILL INTRODUCE  
LLWS POTENTIAL AFTER 03Z TONIGHT, CONTINUING UNTIL THE COLD FRONT  
PASSES LATER TUESDAY MORNING. WINDS WILL GRADUALLY INCREASE  
OVERNIGHT, VEERING FROM SOUTHERLY TO WEST-SOUTHWESTERLY AS THE FRONT  
PASSES. A BAND OF MID-LEVEL CLOUDS WILL PASS ALONG WITH THE FRONT,  
BUT VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE CURRENT  
FORECAST PERIOD.  
 
 
   
LMK WATCHES/WARNINGS/ADVISORIES  
 
KY...NONE.  
IN...NONE.  
 
 
 
 
 
SHORT TERM...CSG  
LONG TERM...CSG  
AVIATION...CSG  
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