690  
FXUS63 KLSX 280356  
AFDLSX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE SAINT LOUIS MO  
1056 PM CDT THU MAR 27 2025  
   
KEY MESSAGES
 
 
- SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DECREASE IN COVERAGE THROUGH  
THIS EVENING. THERE IS STILL SOME POTENTIAL FOR AN ISOLATED  
SEVERE THUNDERSTORM THIS EVENING THAT COULD PRODUCE UP TO  
QUARTER SIZED HAIL NORTH OF I-70.  
 
- THERE WILL BE SEVERAL CHANCES FOR SHOWERS AND THUNDERSTORMS  
FRIDAY NIGHT INTO SUNDAY. A FEW STRONG TO SEVERE THUNDERSTORMS  
ARE POSSIBLE ON SUNDAY.  
 

 
   
SHORT TERM
 
(THROUGH LATE FRIDAY NIGHT)  
ISSUED AT 255 PM CDT THU MAR 27 2025  
 
SHOWERS AND THUNDERSTORMS CONTINUED ALONG AND NORTH OF I-70 IN A  
BAND OF STRONG MOISTURE CONVERGENCE ON THE NOSE OF A LOW LEVEL JET.  
THE RAP IS SHOWING THIS CONVERGENCE GRADUALLY DECREASING AND MOVING  
OFF TO THE NORTHEAST OVER THE NEXT FEW HOURS WHICH SHOULD CAUSE THE  
SHOWERS AND THUNDERSTORMS TO BECOME LESS CONCENTRATED. THERE IS A  
WARM FRONT WHICH HAS NOW MOVED TO JUST SOUTH OF THE AREA OF THE  
AREA OF CONVECTION, ROUGHLY OVER CENTRAL AND SOUTHEAST MISSOURI.  
THERE WILL STILL BE A CHANCE (20-40%) FOR ADDITIONAL SHOWERS AND  
THUNDERSTORMS) OUTSIDE OF THIS BAND OF SHOWERS AND THUNDERSTORMS  
ALONG AND NORTH OF THE WARM FRONT. AS THE WARM FRONT LIFTS  
NORTHWARD THIS EVENING, AND THE LLJ INCREASES IN STRENGTH ONCE  
AGAIN, WE SHOULD SEE ADDITIONAL THUNDERSTORMS DEVELOP LATE THIS  
EVENING AND OVERNIGHT ACROSS NORTHEAST MISSOURI INTO WEST CENTRAL  
AND SOUTH CENTRAL ILLINOIS. THERE STILL REMAINS SOME POTENTIAL FOR  
AN ISOLATED STRONG TO SEVERE THUNDERSTORM WITH THIS ACTIVITY,  
WITH THE MAIN THREAT BEING LARGE HAIL UP TO SIZE OF QUARTERS.  
 
THERE IS A CURRENTLY MARKED DIFFERENCE IN TEMPERATURES ACROSS THE  
WARM FRONT WITH UPPER 40S AND LOWER 50S WHERE IT IS RAINING TO THE  
MIDDLE 70S JUST SOUTHWEST OF THE CWA. I STILL BELIEVE THESE WARMER  
TEMPERATURES WILL MAKE IT INTO CENTRAL AND SOUTHEAST MISSOURI THIS  
AFTERNOON. HIGHS ON FRIDAY STILL LOOK TO BE AROUND 80 DEGREES  
BEHIND THE WARM FRONT.  
 
STILL EXPECT FRIDAY TO BE A DRY DAY AS SHORTWAVE RIDGING MOVES  
ACROSS THE AREA. WE WILL BEGIN TO SEE A CHANCE (20-30%) OF SHOWERS  
MOVE INTO THE SOUTHEAST HALF OF THE CWA BY LATE FRIDAY NIGHT AHEAD  
OF A SOUTHERN STREAM SYSTEM.  
 
BRITT  
 

 
   
LONG TERM
 
(SATURDAY THROUGH NEXT THURSDAY)  
ISSUED AT 255 PM CDT THU MAR 27 2025  
 
WE ARE STILL ON TRACK TO HAVE AN ACTIVE PATTERN OVER THE WEEKEND  
WITH TWO SYSTEMS OF NOTE. THE FIRST WILL BE THE AFOREMENTIONED  
SOUTHERN WAVE WHICH WILL BRING LIKELY POPS (50-70%) OVER SOUTHEAST  
MISSOURI AND SOUTHWEST ILLINOIS ON SATURDAY. THE SECOND WILL BE A  
MORE PRONOUNCED TROUGH THAT WILL MOVE INTO FROM THE WEST. WE WILL  
BE MAINTAINING HIGH POPS ON SUNDAY WITH THE PASSAGE OF THIS TROUGH  
AND THE ATTENDANT COLD FRONT (70-90%). IT STILL APPEARS THAT THE  
BEST CHANCE FOR STRONG TO SEVERE THUNDERSTORMS WILL BE ON SUNDAY  
WHEN THE LREF IS SHOWING JOINT PROBABILITIES OF MUCAPE>500 AND 0-  
500MB SHEAR >30 KNOTS REACHING 70-90%. IT SHOULD STILL BE STATED  
THAT THIS SYSTEM IS NOT EXPECTED TO BE AS SEVERE AS WHAT WE SAW  
TWO WEEKS AGO AS THE OPERATIONAL ECMWF/GFS MASS FIELDS ARE NOT  
NEARLY AS STRONG.  
 
THERE WILL BE ANOTHER TROUGH THE MIDDLE OF NEXT WEEK WHICH WILL  
BRING A CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS TO THE AREA BY  
THE MIDDLE OF NEXT WEEK. THE CLUSTER ANALYSIS ARE ALL SHOWING THIS  
TROUGH, BUT THERE IS A SPREAD IN HOW QUICKLY IT WILL MOVE THROUGH  
THE AREA.  
 
TEMPERATURES WILL FALL BEHIND THE FRONT OVER THE WEEKEND WITH  
NBM/LREF BOTH SHOWING HIGHS ONLY IN THE 50S AND 60S BUT REBOUNDING  
INTO THE 70S BY THE MIDDLE OF NEXT WEEK. THE IQR SPREAD IS FAIRLY  
SMALL WITH THE COOL DOWN, BUT INCREASES AS WE GO THROUGH NEXT WEEK  
GIVEN UNCERTAINTY WITH HOW QUICKLY THE NEXT TROUGH MOVES THROUGH.  
 
BRITT  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)  
ISSUED AT 1048 PM CDT THU MAR 27 2025  
 
A BAND OF SCATTERED SHOWERS AND THUNDERSTORMS IS ORIENTED ROUGHLY  
NORTH TO SOUTH ALONG THE MISSISSIPPI RIVER SLOWLY MOVING EASTWARD,  
IMPACTING KUIN, KSUS, KSTL, AND KCPS CURRENTLY. HOWEVER, THIS  
CONVECTION IS EXPECTED TO BE DEPARTING KSUS, KSTL, AND KCPS BY THE  
BEGINNING OF THE PERIOD, WITH IMPACTS ONLY EXPECTED AT KUIN  
THROUGH THE FIRST FEW HOURS OF THE PERIOD. SHOWERS AND  
THUNDERSTORMS WILL BE CAPABLE OF BRIEF HEAVY RAINFALL THAT WILL  
REDUCE VISIBILITIES. ONCE CONVECTION CLEARS THE LOCAL TERMINALS,  
DRY AND VFR FLIGHT CONDITIONS ARE EXPECTED THROUGH THE REMAINDER  
OF THE PERIOD.  
 
ELMORE  
 

 
   
LSX WATCHES/WARNINGS/ADVISORIES
 
 
MO...NONE.  
IL...NONE.  

 
 

 
 
WFO LSX  
 
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