142  
FXUS63 KLSX 071735  
AFDLSX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE SAINT LOUIS MO  
1235 PM CDT TUE OCT 7 2025  
   
KEY MESSAGES
 
 
-A COOL DOWN WILL KICK OFF TODAY, BRINGING TEMPERATURES BACK TO NEAR  
NORMAL THROUGH THE END OF THE WORK WEEK.  
 
-TEMPERATURES WILL WARM BACK ABOVE NORMAL OVER THE WEEKEND AND  
INTO NEXT WEEK WITH DRY CONDITIONS.  
 

 
   
SHORT TERM
 
(THROUGH LATE WEDNESDAY AFTERNOON)  
ISSUED AT 253 AM CDT TUE OCT 7 2025  
 
AS OF 2 AM A SURFACE COLD FRONT IS DRAPED FROM PITTSFIELD, IL TO  
MEXICO, MO AND MAKING ITS WAY SOUTHEAST THROUGH THE FORECAST  
AREA. SCATTERED SHOWERS AND THUNDERSTORMS ARE FIRING OFF THE 850  
MB FRONT THAT IS LAGGING BEHIND THE SURFACE FRONT BY 60-70 MILES.  
THE SURFACE AND ELEVATED FRONTS WILL PROGRESS SOUTHEAST THROUGH  
THE DAY. AS THEY DO THE 850 MB FRONT IS EXPECTED TO WEAKEN AND  
COVERAGE OF SHOWERS AND THUNDERSTORMS WILL DIMINISH, THOUGH A 20%  
CHANCE OF RAIN WILL STAY IN THE FORECAST UNTIL THE FRONT EXITS THE  
AREA. THE SURFACE FRONT WILL EXIT THE REGION DURING THE FORECAST  
AREA THIS MORNING, WHILE THE ELEVATED FRONT AND CHANCE FOR SHOWERS  
AND THUNDERSTORMS WILL EXIT THE CWA THIS AFTERNOON. TEMPERATURES  
AHEAD OF THE 850 MB FRONT WILL WARM INTO THE MID TO UPPER 70S  
WHILE BEHIND THE ELEVATED FRONT TEMPERATURES WILL BE NEAR NORMAL  
IN THE UPPER 60S TO LOW 70S.  
 
A SURFACE HIGH WILL BUILD INTO THE REGION BEHIND THE COLD FRONT,  
BRINGING COOLER, DRIER AIR INTO THE MID-MISSISSIPPI VALLEY. AT THE  
SAME TIME A MID-LEVEL TROUGH WILL EXIT THE MISSISSIPPI VALLEY WHILE  
A RIDGE BUILDS INTO THE CENTRAL PLAINS IN ITS WAKE, LEAVING THE  
REGION WITHIN NORTHWEST FLOW ALOFT FOR WEDNESDAY.  
 
DELIA  
 

 
   
LONG TERM
 
(WEDNESDAY NIGHT THROUGH MONDAY)  
ISSUED AT 253 AM CDT TUE OCT 7 2025  
 
THE SURFACE HIGH AND NORTHWESTERLY FLOW WILL CONTINUE INTO FRIDAY,  
KEEPING THE COOL, DRY CONTINENTAL AIR IN THE REGION. THE DRY AIR AND  
SURFACE HIGH WILL HELP TEMPERATURES COOL EFFECTIVELY. MINIMUM  
TEMPERATURES THURSDAY AND FRIDAY MORNING WILL FALL AS MUCH AS 10  
DEGREES BELOW NORMAL, IN THE 40S. SOME SHELTERED AREAS IN THE  
HOLLOWS AND RIVER VALLEYS WILL BE ABLE TO ACHIEVE LOWS IN THE UPPER  
30S. HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL IN THE  
LOW 70S GIVEN THE COOL STARTS AND COOLER 850 MB TEMPERATURES.  
 
BY SATURDAY THE MID-LEVEL PATTERN BEGINS TO SHIFT WITH THE AXIS OF  
THE RIDGE OVER THE CENTRAL PLAINS SHIFTING EASTWARD AND THROWING THE  
MID-MISSISSIPPI VALLEY INTO SOUTHWESTERLY FLOW. THIS, COMBINED WITH  
THE EASTWARD SHIFT OF THE SURFACE HIGH AND SUBSEQUENT SOUTHERLY  
SURFACE FLOW, RESULTS IN A WARMING TREND THAT WILL CONTINUE INTO  
NEXT WEEK. TEMPERATURES WILL WARM BACK ABOVE NORMAL IN THIS PATTERN,  
THE 25TH PERCENTILE OF THE INTERQUARTILE SPREAD IS ABOVE NORMAL  
SATURDAY THROUGH THE END OF THE PERIOD. CONFIDENCE IS GROWING IN  
THIS PATTERN CHANGE AS ENSEMBLE GUIDANCE CONTINUES TO BE IN GOOD  
AGREEMENT ON THE PLACEMENT OF THE RIDGE. THOUGH IT SHOULD BE NOTED  
THAT SHIFTS IN THE LOCATION OF THE AXIS AND THE TIMING OF THIS WILL  
IMPACT TEMPERATURES. CONFIDENCE IS HIGHER THAT THE REGION WILL BE  
DRY AFTER TODAY'S COLD FRONT UNDER THE INFLUENCE OF THE DRY AIR MASS  
AND THEN BUILDING MID-LEVEL RIDGE. THIS WILL FURTHER EXACERBATE THE  
DRY CONDITIONS ACROSS THE REGION AS MOST WILL NOT SEE ANY RAIN FROM  
TODAY'S COLD FRONT. AS OF TODAY, IT'S BEEN TWO WEEKS SINCE RAIN  
LAST FELL AT OUR CLIMATE SITES (SEPTEMBER 23RD AT KSTL, KCOU,  
KUIN).  
 
DELIA  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)  
ISSUED AT 1232 PM CDT TUE OCT 7 2025  
 
IFR TO MVFR CEILINGS WILL CONTINUE TO LIFT AND PUSH SOUTHEAST THIS  
AFTERNOON THROUGH THIS EVENING. THE ST. LOUIS AND MID-MISSOURI TAF  
SITES SHOULD EXPECT A RETURN TO VFR CONDITIONS EARLY THIS EVENING,  
WITH THE ENTIRE CWA FOLLOWING BY MIDNIGHT. OTHERWISE, WINDS WILL  
TURN TO NORTHEASTERLY TOMORROW MORNING.  
 
JAJA  
 

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

 
 

 
 
WFO LSX  
 
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