832  
FXUS63 KLSX 021711  
AFDLSX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE SAINT LOUIS MO  
1211 PM CDT TUE JUN 2 2026  
   
KEY MESSAGES
 
 
- TEMPERATURES WILL BE NEAR NORMAL IN THE UPPER 70S TO LOW 80S  
WITH LOW HUMIDITY TODAY AND WEDNESDAY. DRY WEATHER CONTINUES ON  
THURSDAY BUT TEMPERATURES EDGE UP A FEW DEGREES INTO THE LOW AND  
MID 80S WITH INCREASING HUMIDITY.  
 
- WARM WEATHER CONTINUES FRIDAY THROUGH NEXT MONDAY WITH A CHANCE  
FOR SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD.  
 

 
   
SHORT TERM
 
(THROUGH THURSDAY)  
ISSUED AT 302 AM CDT TUE JUN 2 2026  
 
A SPRAWLING HIGH PRESSURE SYSTEM WILL CONTROL OUR WEATHER THROUGH  
THURSDAY AS IT DRIFTS FROM THE GREAT LAKES TODAY TO THE EAST COAST.  
THE HIGH IS CURRENTLY PUSHING A BACK DOOR COLD FRONT FROM THE  
NORTHEAST TO THE SOUTHWEST THROUGH THE FORECAST AREA, AND MUCH DRIER  
AIR IS FILTERING IN BEHIND IT. STRONG INSOLATION DUE TO HIGH JUNE  
SUN ANGLE AND A MOSTLY CLEAR SKY WILL PRODUCE DAYTIME HIGHS AROUND  
80 TODAY AND WEDNESDAY. HOWEVER LIGHT WINDS AND GOOD RADIATIONAL  
COOLING CONDITIONS TONIGHT AND WEDNESDAY NIGHT COMBINED WITH THE  
MUCH LOWER DEW POINT AIR WILL ALLOW TEMPERATURES TO DROP INTO THE  
50S. THE WIND WILL TURN BACK TO THE SOUTH THURSDAY WHICH WILL HELP  
TEMPERATURES WARM A FEW DEGREES OVER TODAY AND WEDNESDAY INTO THE  
MID 80S. THE SOUTHERLY FLOW WILL ALSO BEGIN TO BRING HIGHER  
HUMIDITY BACK INTO THE MID MISSISSIPPI VALLEY WHICH WILL SET THE  
STAGE FOR MORE UNSETTLED WEATHER FOR THE END OF THE WEEK.  
 
CARNEY  
 

 
   
LONG TERM
 
(FRIDAY THROUGH MONDAY)  
ISSUED AT 302 AM CDT TUE JUN 2 2026  
 
MEDIUM RANGE GUIDANCE SHOWS A MID-UPPER LEVEL SHORT WAVE TROUGH  
MOVING FROM THE PLAINS INTO THE MIDWEST THURSDAY NIGHT INTO FRIDAY.  
THIS TRIGGERS CONVECTION OVER EASTERN KANSAS INTO WESTERN MISSOURI  
ON FRIDAY WITH PRECIP MOVING INTO CENTRAL AND NORTHEAST MISSOURI  
DURING THE AFTERNOON. DETERMINISTIC GUIDANCE SHOWS DECREASING  
INSTABILITY ACROSS EAST CENTRAL AND SOUTHEAST MISSOURI INTO  
SOUTHWEST AND SOUTH CENTRAL ILLINOIS. THIS IS BACKED UP BY THE LREF  
MEAN SURFACE BASED AND MOST UNSTABLE CAPE FORECASTS, SO CONVECTION  
LOOKS LIKELY TO RUN OUT OF STEAM BEFORE REACHING THESE AREAS FRIDAY  
AFTERNOON. HOWEVER, PERSISTENT SOUTHERLY FLOW WILL CONTINUE TO BRING  
RICHER MOISTURE INTO THE MISSISSIPPI VALLEY FRIDAY NIGHT INTO  
SATURDAY MORNING WHICH WILL ALLOW CONVECTION TO SPREAD ACROSS THE  
AREA. MODELS DIVERGE SATURDAY NIGHT INTO MONDAY AS THE GFS WINDS UP  
A CLOSED UPPER LEVEL LOW OVER THE GREAT LAKES WHILE THE ECMWF  
DEVELOPS A STRONG RIDGE IN THE SAME LOCATION. IN TERMS OF SENSIBLE  
WEATHER, THE GFS WOULD PUSH A WEAK SURFACE COLD FRONT THROUGH THE  
MID MISSISSIPPI VALLEY SATURDAY NIGHT WHICH LEADS TO A SLIGHTLY  
COOLER BUT MUCH DRIER SUNDAY AND MONDAY. THE ECMWF KEEPS US IN  
DEEP, WARM AND MOIST SOUTHERLY FLOW. IT ALSO SHOWS A MID-UPPER  
LEVEL SHORT WAVE MOVING SLOWLY NORTHEAST THROUGH THE CENTRAL PLAINS  
WHICH CONTINUES TO PRODUCE PRECIP THROUGH MONDAY. THE MAJORITY OF  
THE LREF MEMBERS KEEP PRECIPITATION CHANCES GOING THROUGH MONDAY,  
WHICH MAKES THE DETERMINISTIC GFS LOOK LIKE THE OUTLIER. THE WETTER  
LREF FORECAST ALSO JIVES WITH THE NBM FORECAST, SO I DON'T SEE ANY  
REASON TO DEVIATE AND LOWER POPS AT THIS TIME. HIGHS THROUGH THE  
PERIOD HOVER IN THE MID TO UPPER 80S WITH LOWS IN THE MID TO UPPER  
60S. WITH THAT IN MIND, MAX TS WILL BE HIGHLY DEPENDENT ON  
CONVECTIVE TRENDS EACH DAY.  
 
CARNEY  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)  
ISSUED AT 1209 PM CDT TUE JUN 2 2026  
 
HIGH PRESSURE OVER THE GREAT LAKES WILL MAINTAIN DRY, EASTERLY  
FLOW THROUGH THE PERIOD. THERE IS HIGH CONFIDENCE IN VFR  
CONDITIONS PERSISTING THROUGH WEDNESDAY AFTERNOON.  
 
MAPLES  
 

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

 
 

 
 
WFO LSX  
 
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