577  
FXUS63 KLMK 211823  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
123 PM EST FRI FEB 21 2025  
   
..UPDATED AVIATION DISCUSSION
 
 
   
KEY MESSAGES
 
 
* MOSTLY DRY WEATHER THROUGH THE WEEKEND INTO EARLY NEXT WEEK.  
TEMPERATURES WILL RISE ABOVE FREEZING TODAY OR SATURDAY, WITH  
ABOVE NORMAL TEMPS NEXT WEEK.  
 
* NEXT CHANCE OF RAIN ARRIVES BY THE MIDDLE OF NEXT WEEK.  
 

 
   
UPDATE
 
 
ISSUED AT 1147 AM EST FRI FEB 21 2025  
 
AS HIGH PRESSURE CONTINUES TO EASE INTO THE REGION, WINDS REMAIN  
LIGHT UNDER MOSTLY SUNNY SKIES FOR MOST IN SOUTHERN INDIANA AND  
CENTRAL KENTUCKY. HOWEVER, A LAYER OF STATUS CURRENTLY SITS OVER  
SOUTHEAST INDIANA AND EAST OF LOUISVILLE THROUGH THE BLUEGRASS.  
THROUGHOUT THE DAY, THIS LAYER IS EXPECTED TO SLOWLY MOVE OFF TO THE  
EAST. THE FORECAST REMAINS ON TRACK NEEDING ONLY SLIGHT ADJUSTMENTS.  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 315 AM EST FRI FEB 21 2025  
 
A LARGE SHIELD OF CLOUDS COMING OFF THE GREAT LAKES DROPPED SOUTH  
ACROSS INDIANA AND OHIO OVERNIGHT, SLIPPING INTO NORTHEASTERN  
SECTIONS OF KENTUCKY EARLY THIS MORNING. THESE CLOUDS SHOULD  
GENERALLY PERSIST OVER THE BLUE GRASS THROUGH THE MORNING, THOUGH  
WITH SOME BREAKS. IN TEMPERATURES THIS COLD IT'S NOT DIFFICULT TO  
SQUEEZE A FEW FLURRIES OUT OF EVEN A RELATIVELY THIN STRATUS DECK,  
AND INDEED FLURRIES HAVE BEEN REPORTED AND DETECTED ON RADAR  
UPSTREAM, SO HAVE INCLUDED A SLIGHT CHANCE OF FLURRIES UNDER THE  
CLOUDS. ELSEWHERE SCATTERED DIURNAL CU ARE EXPECTED TO DEVELOP, BUT  
STILL ALLOW A DECENT AMOUNT OF SUNSHINE. THE THICKER CLOUDS OVER THE  
BLUE GRASS THIS MORNING SHOULD BECOME LESS PERVASIVE THIS AFTERNOON  
AS 925-850MB FLOW BACKS FROM NORTHWEST TO WESTERLY, CUTTING OFF THE  
MOISTURE FEED FROM THE LAKES.  
 
THE CENTER OF A STRONG DOME OF HIGH PRESSURE WILL ADVANCE FROM  
KANSAS CITY TO LOUISVILLE TODAY, KEEPING WINDS LIGHT AND  
TEMPERATURES CHILLY. AFTERNOON READINGS SHOULD PEAK NEAR THE  
FREEZING MARK, THOUGH CONFIDENCE IN TEMPERATURES IS SLIGHTLY LESS  
THAN NORMAL DUE TO QUESTIONS OF JUST HOW MUCH CLOUD COVER THERE WILL  
BE, ESPECIALLY IN THE BLUEGRASS.  
 
TONIGHT THE HIGH WILL CONTINUE TO PUSH TO THE EAST INTO THE  
APPALACHIANS. THIS WILL ALLOW TONIGHT TO BE A FEW DEGREES WARMER,  
WITH LOWS IN THE TEENS. A PATCH OF MID-LEVEL CLOUDS OVER COLORADO  
AND KANSAS THIS MORNING IS EXPECTED TO CROSS SOUTHERN INDIANA AND  
NORTH CENTRAL KENTUCKY LATE TONIGHT, FURTHER PREVENTING TEMPERATURES  
FROM GETTING AS COLD AS THEY DID THIS MORNING.  
 

 
   
LONG TERM /SATURDAY THROUGH THURSDAY/
 
 
ISSUED AT 315 AM EST FRI FEB 21 2025  
 
SYNOPSIS...AN ARCTIC SURFACE HIGH PRESSURE ALONG WITH RISING MID-  
LEVEL HEIGHTS MOVING FROM THE CENTRAL US WILL DOMINATE THROUGH THE  
WEEKEND RESULTING IN DRY WEATHER AND RISING TEMPERATURES. AMPLIFYING  
MID-LEVEL RIDGE OVER THE WEST CONUS WILL CONTINUE BUILDING EASTWARD  
WITH AN OVERALL SPLIT FLOW DOWNSTREAM AS THE POLAR JET FLOWS ACROSS  
THE NORTHERN PLAINS/GREAT LAKES AND THE SUBTROPICAL JET REMAINS OVER  
THE GULF. THEN, DOWNSTREAM PATTERN AMPLIFICATION IS EXPECTED TO TAKE  
PLACE BY THE SECOND HALF OF NEXT WEEK AS PERSISTENT ACTION OF  
NORTHERN-STREAM SHORTWAVE ENERGY CARVES A TROUGH OVER THE EAST  
CONUS. ALTHOUGH CONFIDENCE REMAINS LOW FOR THE LATTER PORTION OF THE  
FORECAST, THE FORECAST STILL REFLECTS INCREASING RAIN CHANCES AND A  
SLIGHT TEMPERATURE COOL DOWN.  
 
MODEL EVALUATION/CONFIDENCE...
AS ALLUDED TO ABOVE, FORECAST  
CONFIDENCE CONSIDERABLY DECREASES TOWARDS THE MIDDLE OF NEXT WEEK  
GIVEN HIGH MODEL VARIABILITY HANDLING THE DOWNSTREAM PATTERN  
AMPLIFICATION AND SHORTWAVE ENERGY PHASING. THE LATEST GFS AND CMC  
MODEL RUNS HAVE DELAYED THE TIMING FOR THE AMPLIFICATION AND, AS A  
RESULT, THE ATTENDANT SURFACE LOW IS FARTHER NORTH AND MUCH WEAKER  
WHICH YIELDS A MUCH DRIER QPF SIGNAL WEDNESDAY INTO THURSDAY. THIS  
DRIER TREND IS ALSO NOTED IN THE 20/0Z RUN OF THE ECMWF; HOWEVER,  
THE UKMET AND ICON DETERMINISTIC GUIDANCE ARE ON THE WETTER SIDE OF  
THE SPECTRUM RESEMBLING PREVIOUS RUNS OF THE GFS/CMC/ECMWF. OVERALL,  
THERE IS MEDIUM CONFIDENCE (AT BEST) IN RAIN CHANCES WITH LOW  
CONFIDENCE IN AMOUNTS AND LOCATION.  
 
SATURDAY - MONDAY...MOST NOTABLE CHANGE DURING THIS PERIOD WILL BE  
THE HIGHLY ANTICIPATED TEMPERATURE WARM UP WITH BOTH LOWS AND HIGHS  
GOING FROM DOUBLE-DIGIT BELOW-NORMAL VALUES ON SATURDAY TO SINGLE  
DIGIT ABOVE-AVERAGE VALUES ON MONDAY. ARCTIC SURFACE HIGH PRESSURE  
AND BUILDING MID-LEVEL HEIGHTS WILL FOMENT DRY AND MOSTLY SUNNY  
WEATHER EVEN THOUGH SATURDAY WILL START OFF CLOUDY AS A SMALL  
AMPLITUDE VORT MAX CROSSES THE OHIO VALLEY.  
 
TUESDAY - FRIDAY...SURFACE HIGH PRESSURE WILL EVENTUALLY MOVE DEEPER  
INTO THE SOUTHEAST US WHILE THE OHIO VALLEY BECOMES MORE INFLUENCED  
BY THE INCREASINGLY ACTIVE NORTHERN-STREAM SHORTWAVES AND  
ACCOMPANYING LOW PRESSURE SYSTEMS. ALTHOUGH THE RICHER MOISTURE FEED  
FROM THE GULF WILL BE BLOCKED BY THE HIGH PRESSURE CIRCULATION,  
MODIFIED PACIFIC AIRMASS ACCOMPANYING THE WESTERLIES WILL SUPPORT  
THE INTRODUCTION OF LIGHT RAIN CHANCES/SPRINKLES ACROSS THE NORTHERN  
EXTENT OF THE FORECAST AREA ON TUESDAY. THE WEDNESDAY/THURSDAY  
PERIOD STILL HOLDS THE BEST CHANCE OF MEASURABLE RAINFALL FOR THE  
REGION, BUT LOW CONFIDENCE PREVENTS DELVING INTO ADDITIONAL DETAILS  
SUCH AS TOTAL QPF, TIMING OF HEAVIEST RAINFALL, OR HYDROLOGICAL  
IMPACTS. FINALLY, A BRIEF PERIOD OF BELOW-NORMAL TEMPERATURES AND  
LIGHT FROZEN PRECIPITATION MIGHT FOLLOW THE PASSAGE OF THE COLD  
FRONT ON FRIDAY.  
 

 
   
AVIATION /18Z TAFS THROUGH 00Z SUNDAY/
 
 
ISSUED AT 123 PM EST FRI FEB 21 2025  
 
OVERALL THE PERIOD WILL REMAIN QUIET, BUT THE AREA OF STRATUS OVER  
LEX AND RGA IS EXPECTED TO LAST THOUGH THE AFTERNOON AND EVENING  
HOURS. THE TAFS COULD BE A LITTLE PESSIMISTIC IN REGARD TO THE  
CEILING AT THOSE TWO SITES, BUT THESE LAYERS TEND TO LAST LONGER  
THAN EXPECTED. WINDS AT ALL THE SITES WILL REMAIN LIGHT AS HIGH  
PRESSURE CONTINUES TO MOVE EAST TOWARDS THE REGION. A PASSING WAVE  
TOMORROW WILL PUSH SOME MID LEVEL CLOUDS THROUGH THE AREA.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
KY...NONE.  
IN...NONE.  
 

 
 

 
 
UPDATE...KDW  
SHORT TERM...13  
LONG TERM...ALL  
AVIATION...KDW  
 
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