028  
FXUS63 KLMK 250806  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
306 AM EST SUN FEB 25 2024  
   
KEY MESSAGES
 
 
* BREEZY, MILD, AND DRY SUNDAY EXPECTED  
 
* TURNING VERY MILD AND BREEZY EARLY NEXT WEEK, WITH HIGHS IN THE  
LOW 70S ON MONDAY AND TUESDAY  
 
* SCATTERED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TUESDAY  
MORNING AHEAD OF AN APPROACHING STORM SYSTEM  
 
* A COLD FRONT WILL BRING A CHANCE OF THUNDERSTORMS AND GUSTY WINDS  
TUESDAY NIGHT INTO WEDNESDAY MORNING. ALTHOUGH CONFIDENCE REMAINS  
LOW, STRONG TO POTENTIALLY SEVERE STORMS CANNOT BE RULED OUT  
 

 
   
SHORT TERM /THROUGH TONIGHT/
 
 
ISSUED AT 300 AM EST SUN FEB 25 2024  
 
SYNOPSIS...POSITIVE UPPER-LEVEL HEIGHT ANOMALIES WILL BUILD OVER THE  
AREA DURING THE NEXT 24 HOURS AS A RIDGE EXTENDS FROM THE SOUTHWEST  
US TO THE GREAT LAKES BEHIND A DEPARTING CANADIAN SHORTWAVE TROUGH.  
AT LOWER LEVELS, A SURFACE HIGH PRESSURE WILL CONTINUE TRACKING TO  
THE SOUTHEAST ATLANTIC COAST WHILE WEAK AREA OF LOW PRESSURE STALLS  
ACROSS THE MIDWEST. THE AFOREMENTIONED LARGE-SCALE SETUP WILL  
PROMOTE DECENT THETA-E ADVECTION AS A RIBBON OF ENHANCED LOW-LEVEL  
FLOW STRETCHES FROM THE WESTERN GULF OF MEXICO TO THE OHIO VALLEY  
THIS AFTERNOON AND EVENING.  
 
TODAY...LATEST SURFACE OBSERVATIONS REPORT LIGHT AND/OR VARIABLE  
WINDS THROUGHOUT THE FORECAST AREA UNDER MOSTLY CLEAR SKIES AND  
FALLING TEMPERATURES THANKS TO SURFACE HIGH PRESSURE CURRENTLY  
LOCATED OVER EASTERN TENNESSEE. EXPECT TEMPERATURES TO GRADUALLY  
LEVEL BEFORE SUNRISE IN RESPONSE TO WINDS PICKING UP FROM THE SOUTH  
GIVEN THE EASTWARD DISPLACEMENT OF THE HIGH. TEMPERATURES WILL  
QUICKLY RISE DURING THE MORNING HOURS DUE TO THE COMBINATION OF  
UNOBSTRUCTED SOLAR RADIATION AND WARM AIR ADVECTION. A LOW- TO MID-  
LEVEL CLOUD DECK IS FORECAST TO TRANSITION THROUGH THE TN/OH VALLEY  
DURING THE AFTERNOON, BUT NO PRECIPITATION IS ANTICIPATED BASED ON  
CLOUD LAYER DEPTH AND PLENTY OF DRY AIR BELOW 700 MB. OTHERWISE,  
TIGHTENING PRESSURE GRADIENT WILL ALLOW GUSTY WINDS BETWEEN 20 TO 30  
MPH FROM NOON TO AROUND SUNSET.  
 
TONIGHT...ALTHOUGH WINDS WILL RELAX OVERNIGHT, THE SLIGHT  
ENHANCEMENT OF THE 850-MB FLOW MOVING ACROSS THE TN/OH VALLEYS WILL  
PROVIDE ENOUGH MOMENTUM AT THE SURFACE TO MAINTAIN THE SOUTHERLY  
COMPONENT AND KEEP TEMPERATURES WELL ABOVE THE FREEZING MARK. AT THE  
SAME TIME, MODELS ARE SHOWING AN UPTICK IN PW VALUES ASSOCIATED WITH  
THE JET CORE (40-45 KNOTS) WHICH COULD TRANSLATE INTO A THICKER AND  
LOWER CLOUD LAYER POTENTIALLY LEADING TO SPOTTY LIGHT RAIN/SPRINKLE  
CHANCES OVER SOUTH CENTRAL KENTUCKY. HOWEVER, CONFIDENCE IN  
ACCUMULATING RAINFALL IS LOW BASED ON THE DEWPOINT DEPRESSION VALUES  
IN THE LOWEST KILOMETER.  
 

 
   
LONG TERM /MONDAY THROUGH SATURDAY/
 
 
ISSUED AT 300 AM EST SUN FEB 25 2024  
 
MONDAY...  
 
PROGRESSIVE, ZONAL FLOW ALOFT WILL BE IN PLACE ACROSS MUCH OF THE  
CONUS ON MONDAY. LOW-AMPLITUDE RIDGING IS CENTERED OVER THE CENTRAL  
AND SOUTHERN CONUS AS A DIGGING UPPER LEVEL TROUGH MOVES SOUTHEAST  
OVER THE PACIFIC NORTHWEST. DOWNSTREAM, SFC LOW PRESSURE IS FORECAST  
TO DEVELOP ACROSS PORTIONS OF THE NORTHERN PLAINS. LOCALLY,  
SOUTHWESTERLY LOW-LEVEL FLOW IS FORECAST TO INCREASE LATER IN THE  
DAY. STEADY WARM AIR ADVECTION IS EXPECTED, AND FORECAST SOUNDINGS  
SHOW A FAIRLY DRY COLUMN. EXPECT MOSTLY SUNNY SKIES AND VERY MILD  
CONDITIONS WITH THE POTENTIAL FOR OVERACHIEVING TEMPERATURES. MUCH  
LIKE PREVIOUS FORECASTS, HAVE GONE A BIT WARMER THAN THE OPERATIONAL  
NBM GIVEN THE SYNOPTIC PATTERN. MOST AREAS SHOULD SEE HIGHS IN THE  
UPPER 60S TO LOWER 70S, BUT WOULD NOT BE SURPRISED TO SEE A COUPLE  
URBAN AREAS TOP OUT IN THE MID 70S.  
 
MONDAY NIGHT - WEDNESDAY NIGHT...  
 
THE AFOREMENTIONED UPPER LEVEL TROUGH OVER THE PACIFIC NORTHWEST IS  
FORECAST TO DEVELOP ESE ACROSS THE ROCKIES AND CENTRAL/NORTHERN  
PLAINS BEFORE REACHING THE UPPER/MID-MISSISSIPPI VALLEY BY  
WEDNESDAY. THIS INTENSIFIES AN UPPER LEVEL JET STREAK TO ~180 KTS  
FROM THE SOUTHWEST US TO KANSAS, PROMOTING DEEP VERTICAL ASCENT AND  
SFC CYCLOGENESIS BENEATH THE LEFT EXIT REGION. THIS WILL ONLY  
ENHANCE AN ALREADY STRONG BAROCLINIC ZONE. SFC WAVES DEVELOP,  
DEEPEN, AND MOVE NORTHEAST ALONG THE EVOLVING BAROCLINIC ZONE FROM  
THE PLAINS NORTHEAST THROUGH THE GREAT LAKES.  
 
THIS STRONG LOW PRESSURE SYSTEM WILL PROMOTE AN EXTENDED PERIOD OF  
STRONG SW LOW-LEVEL FLOW AND POTENT WAA/MOISTURE TRANSPORT INTO THE  
OHIO VALLEY MONDAY NIGHT INTO WEDNESDAY. TEMPERATURES MAY FLIRT WITH  
RECORD HIGHS OR, MORE LIKELY, RECORD WARM LOWS MONDAY THROUGH  
TUESDAY NIGHT.  
 
A SUBTLE MID-LEVEL SHORTWAVE TROUGH ZIPS OVER THE OHIO VALLEY MONDAY  
NIGHT WITHIN THE PROGRESSIVE FLOW ALOFT, AND THE SOUTHWESTERLY LOW-  
LEVEL JET STRENGTHENS TO 45+ KTS. THIS MAY BE SUFFICIENT FORCING TO  
OVERCOME A WARM CAPPING LAYER ALOFT AND SPARK ISOLATED TO WIDELY  
SCATTERED SHOWERS AND STORMS. LREF CAPE ACTUALLY PEAKS IN THE LOWER  
OHIO VALLEY EARLY TUESDAY, AND JOINT PROBABILITIES OF > 250/500 J/KG  
CAPE AND > 30 KTS DEEP-LAYER SHEAR ARE MAXIMIZED AROUND 12Z TUE.  
ABOVE THE WARM INHIBITING LAYER, FORECAST SOUNDINGS SHOW RATHER  
STEEP MID-LEVEL LAPSE RATES WITH MORE THAN SUFFICIENT DEEP-LAYER  
SHEAR. FORECAST CONFIDENCE IS ONLY LOW-MEDIUM AT THIS TIME, BUT IF  
WE CAN GET A COUPLE TALLER UPDRAFTS TO DEVELOP, THEN THESE ELEVATED  
STORMS COULD BECOME STRONG WITH LOCALLY HEAVY RAINFALL AND AT LEAST  
SMALL HAIL.  
 
AFTER THE MORNING WAVE OF SHOWERS AND ISOLATED STORMS TUE MORNING,  
WE WILL SEE AT LEAST A BRIEF LULL IN THE ACTION TUE  
AFTERNOON/EVENING. IT IS WORTH NOTING THAT THE MESOSCALE DETAILS ARE  
VERY MURKY AT THIS TIME RANGE, HOWEVER. ADDITIONAL CONVECTION,  
POSSIBLY SUPERCELLULAR AT TIMES, DOES LOOK LIKELY OFF TO OUR NORTH  
AND WEST IN PORTIONS OF MO/IL TUE AFTERNOON AND EVENING AS A STRONG  
COLD FRONT BARRELS IN. EVEN OUTSIDE OF SHOWER/STORM ACTIVITY, EXPECT  
A WINDY AND WARM TUESDAY WITH GUSTS OVER 30 MPH. HIGHS WILL AGAIN  
REACH THE 70S.  
 
UPSCALE GROWTH INTO A QLCS IS POSSIBLE BY TUESDAY NIGHT AS SHOWERS  
AND STORMS MOVE INTO THE LOWER OHIO VALLEY. DEEP-LAYER FORCING FOR  
ASCENT AND SHEAR ARE MAXIMIZED TUESDAY NIGHT INTO WEDNESDAY MORNING  
GIVEN THE VERY STRONG FRONTAL CIRCULATION AND APPROACHING  
TROUGH/IMPRESSIVE WIND FIELDS ALOFT. INSTABILITY WILL LIKELY BE AT A  
MINIMUM, AND THIS MAY VERY WELL LIMIT THE OVERALL SEVERE WEATHER  
THREAT. HOWEVER, GIVEN THE MAGNITUDE OF THE FORCING AND THE LOW TO  
MID-LEVEL WIND FIELDS, THERE IS CONCERN FOR AT LEAST ISOLATED  
DAMAGING WINDS AND PERHAPS BRIEF TORNADOES WITH MESOVORTICES  
DEVELOPING ALONG A QLCS. AT THE VERY LEAST, EXPECT STRONG GRADIENT  
WINDS WITH GUSTS IN EXCESS OF 40 MPH. TUE NIGHT WILL BE VERY MILD  
WITH TEMPS HOVERING NEAR 60 F.  
 
MODELS HAVE CONVERGED SLIGHTLY ON TIMING, AND FROPA IS POSSIBLE  
AROUND 12-18Z WEDNESDAY THOUGH EXPECT THAT TO STILL SHIFT SLIGHTLY  
OVER THE NEXT DAY OR TWO. SHOWERS, POSSIBLE ISOLATED STORMS, AND  
GUSTY WINDS WILL LINGER INTO THE AFTERNOON HOURS. PRECIPITATION MAY  
TRY TO END AS A VERY BRIEF WINTRY MIX, BUT PRECIP WILL SHUT OFF  
ABRUPTLY IN THE WAKE OF THE FRONT AS COLD, DRY AIR PLUNGES INTO THE  
REGION. TEMPERATURES ARE FORECAST TO FALL INTO THE 20S BY DAYBREAK  
THURSDAY.  
 
THURSDAY - SATURDAY...  
 
THURSDAY LOOKS COOL AND SUNNY AS STRONG HIGH PRESSURE MOVES INTO THE  
REGION. HIGHS SHOULD BE IN THE 40S. CONDITIONS WARM BACK UP RATHER  
QUICKLY INTO THE 50S AND 60S FRIDAY INTO NEXT WEEKEND. THERE IS ONLY  
A SMALL CHANCE (20-30%) FOR RAIN AT THIS TIME.  
 

 
   
AVIATION /06Z TAFS THROUGH 12Z MONDAY/
 
 
ISSUED AT 1225 AM EST SUN FEB 25 2024  
 
IMPACTS/CONFIDENCE:  
- HIGH CONFIDENCE IN GUSTY SOUTHERLY WINDS THIS AFTERNOON  
- MEDIUM CONFIDENCE IN LLWS AT BWG TONIGHT  
 
DISCUSSION...VFR CONDITIONS WILL PREVAIL DURING THIS TAF PERIOD.  
SURFACE HIGH PRESSURE MOVING TO THE EAST IS SUPPORTING LIGHT AND  
VARIABLE WINDS TONIGHT ALTHOUGH A SHIFT TO THE SOUTH IS EXPECTED  
CLOSE TO SUNRISE. THEN, PRESSURE GRADIENT BETWEEN THE DEPARTING HIGH  
AND LOWER PRESSURES IN THE UPPER MIDWEST WILL SLOWLY BUILD UP TO  
ACCOUNT FOR OCCASIONAL SOUTHERLY WIND GUSTS OF 20-25 KNOTS. FOR  
TONIGHT, WINDS WILL RELAX ONCE AGAIN BUT THE PRESENCE OF A DECENT  
850-MB IMPULSE ACROSS SOUTH CENTRAL KY WILL PROBABLY JUSTIFY  
MENTIONING LLWS AT BWG WITH LESS CONFIDENCE FOR LEX AND SDF.  
 

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

 
 

 
 
SHORT TERM...ALL  
LONG TERM...EBW  
AVIATION...ALL  
 
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