054  
FXUS63 KLMK 201644  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
1144 AM EST SAT DEC 20 2025  
   
..FORECAST UPDATE  
 
   
KEY MESSAGES  
 
* UP AND DOWN TEMPERATURES EXPECTED THIS WEEKEND AS A DRY COLD FRONT  
MOVES THROUGH THE REGION TONIGHT.  
 
* OFF AND ON CHANCES FOR LIGHT RAIN SHOWERS ARE EXPECTED MONDAY  
AFTERNOON THROUGH WEDNESDAY, THOUGH A WASHOUT IS UNLIKELY.  
 
* UNSEASONABLY WARM TEMPERATURES ARE LIKELY AROUND CHRISTMAS, WITH  
HIGHS IN THE 60S TO AROUND 70 LIKELY FROM CHRISTMAS EVE THROUGH  
FRIDAY.  
 
 
   
UPDATE  
 
ISSUED AT 1144 AM EST SAT DEC 20 2025  
 
THE FORECAST IS ON TRACK TODAY FOR A MOSTLY SUNNY, OCCASIONALLY  
GUSTY, AND MILD OVERALL DAY. DID LOWER DEW POINTS DOWN TO NBM 10TH  
PERCENTILE FOR THIS AFTERNOON AND EVENING TO ACCOUNT FOR GOOD BL  
MIXING AND EXPECTED DRY AIR MIX DOWN. OVERALL, LITTLE CONSEQUENCE ON  
THE OVERALL FORECAST AS SENSIBLE WEATHER ISN'T REALLY AFFECTED AND  
THE FIRE WEATHER SEASON HAS ENDED.  
 
 
   
SHORT TERM /THROUGH SUNDAY/  
 
ISSUED AT 306 AM EST SAT DEC 20 2025  
 
THIS MORNING, MOSTLY ZONAL UPPER LEVEL FLOW IS PRESENT ACROSS THE  
CONUS AS THE TROUGH WHICH BROUGHT A COLD FRONT THROUGH THE REGION  
FRIDAY MORNING HAS QUICKLY EXITED TOWARD THE CANADIAN MARITIMES. A  
BROAD AREA OF SFC HIGH PRESSURE IS ANALYZED FROM THE CENTRAL  
APPALACHIANS DOWN INTO THE SOUTHEAST US, WHILE SFC LOW PRESSURE  
EXTENDS FROM THE MB/ON BORDER SOUTHWARD INTO THE CENTRAL PLAINS.  
WHILE MOST AREAS HAVE FALLEN INTO THE 20S ACROSS SOUTHERN IN AND  
CENTRAL KY, MILDER TEMPERATURES ARE LOCATED IMMEDIATELY TO OUR WEST,  
AS SOUTHERLY FLOW IS BRINGING WAA INTO THE OZARKS AND MID-MS VALLEY.  
 
AS WE HEAD THROUGH THE DAY TODAY, AN UPPER SHORTWAVE OVER THE  
CANADIAN PRAIRIES IS EXPECTED TO PIVOT TO THE E/SE ACROSS THE UPPER  
GREAT LAKES. AS IT DOES SO, THE ASSOCIATED SFC COLD FRONT ACROSS THE  
PLAINS WILL MOVE EASTWARD ACROSS THE MISSISSIPPI VALLEY, PASSING  
THROUGH THE AREA THIS EVENING INTO TONIGHT. WINDS WILL INCREASE OUT  
OF THE S/SW LATER THIS MORNING, WITH WIND GUSTS OF 20-30 MPH LIKELY  
AS MOMENTUM FROM A LLJ MOVING OVER THE REGION MIX DOWN BY AROUND  
MIDDAY. STRONG WARM ADVECTION SHOULD HELP TEMPERATURES RECOVER INTO  
THE 50S THIS AFTERNOON, WITH A MIX OF SUN AND MAINLY HIGH CLOUDS  
EXPECTED THROUGH THE DAY.  
 
LATER THIS AFTERNOON INTO THIS EVENING, A NARROW TONGUE OF GREATER  
850-925 MB MOISTURE WILL ATTEMPT TO NOSE INTO THE REGION FROM THE SW  
AHEAD OF THE COLD FRONT. WHILE THIS MOISTURE SURGE SHOULD BE  
SUFFICIENT TO INCREASE LOW-TO-MID LEVEL CLOUD COVER THIS EVENING,  
THE OVERALL LACK OF DEEP MOISTURE SHOULD CURTAIL PRECIPITATION  
CHANCES, EVEN WITH FROPA. WITH THAT BEING SAID, A SPOTTY SPRINKLE OR  
LIGHT RAIN SHOWER CAN'T BE RULED OUT SOUTH OF THE KY PARKWAYS THIS  
EVENING, THOUGH IMPACTS SHOULD BE MINIMAL. WINDS ARE EXPECTED TO  
SWING AROUND TO THE NW WITH FROPA, BRING CAA BACK INTO THE REGION BY  
SUNDAY MORNING. TEMPERATURES SUNDAY MORNING ARE EXPECTED TO RANGE  
FROM THE UPPER 20S ACROSS SOUTHERN IN TO THE MID 30S ALONG THE KY/TN  
BORDER.  
 
FOR THE DAY ON SUNDAY, COOL AND DRY WEATHER IS EXPECTED AS HIGH  
PRESSURE SETTLES INTO THE OHIO VALLEY. LINGERING CLOUDS ACROSS KY IN  
THE MORNING SHOULD GRADUALLY DISSIPATE AS BROAD SUBSIDENCE DRIES OUT  
THE COLUMN. LIGHT NORTHERLY FLOW WILL KEEP WEAK COLD ADVECTION GOING  
THROUGH THE DAY, WITH HIGH TEMPERATURES EXPECTED TO RANGE FROM NEAR  
40 ACROSS SOUTHERN IN TO THE MID-TO-UPPER 40S ACROSS SOUTHERN KY.  
 
 
   
LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/  
 
ISSUED AT 306 AM EST SAT DEC 20 2025  
 
SUNDAY NIGHT INTO MONDAY MORNING, SEASONABLY COOL AND DRY CONDITIONS  
ARE EXPECTED TO CONTINUE AS SFC HIGH PRESSURE STARTS TO PUSH EAST  
TOWARD THE CENTRAL APPALACHIANS. LOW TEMPERATURES MONDAY MORNING  
SHOULD SINK INTO THE 20S IN MOST AREAS.  
 
MONDAY WILL BEGIN A TRANSITION TO A MILDER PATTERN, WITH FAIRLY GOOD  
CONFIDENCE IN THIS PATTERN REMAINING IN PLACE THROUGH CHRISTMAS AND  
INTO NEXT WEEKEND. AN UPPER TROUGH WILL PROGRESSIVELY DIG OFF THE  
WEST COAST OF THE US OVER THE FIRST HALF OF THE UPCOMING WEEK, WITH  
DOWNSTREAM RIDGING OVER THE SOUTH CENTRAL US BUILDING NORTHWARD AT  
THE SAME TIME. THIS WILL PLACE THE OHIO VALLEY INTO A NW FLOW  
PATTERN FOR MUCH OF THE FIRST HALF OF NEXT WEEK, THOUGH THE COUPLED  
SUBTROPICAL/POLAR JET IS EXPECTED TO LIFT WELL TO THE NORTH INTO  
SOUTHERN CANADA. WHILE SEVERAL SHORTWAVES ARE EXPECTED TO SLIDE FROM  
NW TO SE WITHIN THE MAIN BAROCLINIC ZONE, OUR REGION SHOULD BE ON  
THE SOUTHWESTERN EDGE OF THE BEST FORCING, RESULTING IN FAIRLY  
LIMITED IMPACTS.  
 
THE FIRST OF THE ABOVE-MENTIONED SHORTWAVES IS EXPECTED TO SLIDE  
ACROSS THE CANADIAN PRAIRIES AND INTO THE UPPER GREAT LAKES MONDAY  
NIGHT INTO TUESDAY. WHILE THE MAIN PORTION OF THE DISTURBANCE WILL  
REMAIN WELL NORTH OF THE AREA, S/SW LOW-LEVEL FLOW IS EXPECTED TO  
PICK UP ENOUGH MOISTURE LINGERING OVER THE GULF STATES TO SUPPORT  
SOME WARM ADVECTION/ISENTROPIC LIFT RAIN SHOWERS MONDAY AFTERNOON  
INTO MONDAY NIGHT. THESE SHOWERS ARE EXPECTED TO BE LIGHT, WITH  
PRECIPITATION AMOUNTS OF A TENTH OF AN INCH OR LESS EXPECTED IN MOST  
AREAS.  
 
A COLD FRONT IS EXPECTED TO APPROACH FROM THE NW ON TUESDAY MORNING;  
HOWEVER, GIVEN THE PERSISTENT BUILDING RIDGE TO OUR SW, THIS FRONT  
IS UNLIKELY TO MAKE IT COMPLETELY THROUGH THE REGION, WITH MOST  
PROGS SHOWING IT STALLING OUT SOMEWHERE OVER KY/TN TUESDAY NIGHT.  
WITH AMPLE MOISTURE REMAINING ALONG THE FRONT, SCATTERED SHOWERS,  
AMPLE CLOUD COVER, AND POSSIBLY SOME DRIZZLE WILL CONTINUE INTO  
TUESDAY AND TUESDAY NIGHT. WHILE NBM POPS MAY BE A TOUCH OVERDONE  
GIVEN LIMITED QPF, THINK THE GENERAL MESSAGE THAT ANYONE COULD SEE A  
LIGHT RAIN SHOWER ON TUESDAY IS APPROPRIATE.  
 
THE UPPER RIDGE IS EXPECTED TO SPREAD EASTWARD TUESDAY NIGHT INTO  
CHRISTMAS EVE, CAUSING THE DECAYING COLD FRONT NEAR THE AREA TO LIFT  
BACK TO THE NORTH AS A WARM FRONT, INCREASING WARM RETURN FLOW INTO  
THE AREA. WHILE MONDAY AND TUESDAY SHOULD SEE A GRADUAL WARMING  
TREND, WITH HIGHS MOSTLY IN THE 50S AND LOWS IN THE 40S, THE PEAK OF  
THE WARM TEMPERATURES ARE EXPECTED FROM CHRISTMAS EVE THROUGH  
FRIDAY. HIGH TEMPERATURES ARE EXPECTED TO SURGE INTO THE 60S ACROSS  
THE AREA, PARTICULARLY ON CHRISTMAS DAY, WHEN PROBABILITIES OF  
EXCEEDING 70 ARE AROUND 50% ACROSS MUCH OF SOUTH CENTRAL KY. WHILE  
LOW CHANCES FOR RAIN SHOWERS CURRENTLY LINGER INTO CHRISTMAS EVE AND  
CHRISTMAS MORNING, MOST AREAS SHOULD REMAIN DRY, ESPECIALLY BY THE  
SECOND HALF OF CHRISTMAS DAY ONCE THE UPPER RIDGE AXIS BUILDS  
OVERHEAD.  
 
BY THE END OF THE WEEK INTO EARLY NEXT WEEKEND, THE MEDIUM RANGE  
ENSEMBLE CONSENSUS SUGGESTS THAT THE UPPER RIDGE WILL BEGIN TO BREAK  
DOWN, OR AT LEAST FLATTEN OUT A BIT AS SOME OF THE ENERGY FROM  
TROUGHING ALONG THE WEST COAST EJECTS OUT ACROSS THE CENTRAL CONUS.  
THIS SHOULD BRING RETURNING CHANCES FOR PRECIPITATION AND A DOWNWARD  
TREND IN TEMPERATURES; HOWEVER, DETAILS ON THE MAGNITUDE OF THE COOL-  
DOWN AND PRECIPITATION CHANCES ARE STILL MODEST AT THIS TIME. WITH  
THAT BEING SAID, THERE DOESN'T APPEAR TO BE ANY PATTERN REVERSAL IN  
STORE THROUGH NEW YEAR'S, WITH ELEVATED CHANCES OF ABOVE NORMAL  
TEMPERATURES PERSISTING IN THE CURRENT CPC 8-14 DAY OUTLOOK.  
 
 
   
AVIATION /12Z TAFS THROUGH 18Z SUNDAY/  
 
ISSUED AT 635 AM EST SAT DEC 20 2025  
 
VFR CONDITIONS ARE EXPECTED THROUGH THE CURRENT FORECAST PERIOD,  
WITH LLWS AND GUSTY WINDS BEING THE PRIMARY DRIVERS FOR FORECAST  
CHANGES LATER TODAY AND INTO TONIGHT. VAD WIND PROFILES ARE  
BEGINNING TO SHOW 30 KT S/SW WINDS AT ABOUT 1500 FT AGL; THIS SHOULD  
CONTINUE TO INCREASE OVER THE NEXT SEVERAL HOURS AS THE CORE OF THE  
LLJ APPROACHES THE REGION. BY LATE MORNING, IT IS EXPECTED THAT  
THERE WILL BE ENOUGH MIXING FOR SOME OF THE STRONGER WINDS ALOFT TO  
MAKE IT TO THE SURFACE. WHILE MOST OF THE WIND GUSTS SHOULD BE  
AROUND 20 KT, THERE MAY BE OCCASIONAL 25-30 KT GUSTS DURING PEAK  
MIXING. TONIGHT, A COLD FRONT WILL MOVE THROUGH THE AREA, BRINGING A  
~5K FT DECK AND A WIND SHIFT FROM S/SW TO NW AS IT PASSES BY. LIGHT  
NORTHERLY WINDS WILL CONTINUE THROUGH THE END OF THE CURRENT  
FORECAST PERIOD.  
 
 
   
LMK WATCHES/WARNINGS/ADVISORIES  
 
KY...NONE.  
IN...NONE.  
 
 
 
 
 
UPDATE...BJS  
SHORT TERM...CSG  
LONG TERM...CSG  
AVIATION...CSG  
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