497  
FXUS63 KLOT 151836 CCA  
AFDLOT  
 
AREA FORECAST DISCUSSION...CORRECTED  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
136 PM CDT MON SEP 15 2025  
   
KEY MESSAGES
 
 
- WARM AND DRY CONDITIONS PERSIST THROUGH THE WORK WEEK.  
 
- PERIODIC SHOWER AND THUNDERSTORM CHANCES RETURN FOR THE WEEKEND  
(20-40%).  
 

 
   
DISCUSSION
 
 
ISSUED AT 136 PM CDT MON SEP 15 2025  
 
A BLOCKY UPPER-LEVEL FLOW PATTERN, CENTERED ACROSS THE GREAT  
LAKES, WILL CONTINUE TO SUPPORT QUIESCENT WEATHER CONDITIONS  
ACROSS OUR AREA THROUGH THE WEEK. ACCORDINGLY, DRY WEATHER WITH  
MOSTLY CLEAR SKIES EACH DAY WILL FOSTER UNSEASONABLY WARM  
TEMPERATURES, WITH INLAND HIGHS IN THE 80S TO NEAR 90 (WARMEST  
TOWARD WESTERN AND CENTRAL ILLINOIS) THROUGH THE REMAINDER OF THE  
WORK WEEK. CLOSER TO THE LAKE, RELATIVELY WEAK SURFACE FLOW AMIDST  
EXPANSIVE SURFACE HIGH PRESSURE WILL FAVOR DAILY INLAND DRIFTING  
LAKE BREEZES. THIS WILL THUS RESULT IN COOLER TEMPERATURES (MAINLY  
IN THE 70S) NEAR THE LAKE MICHIGAN LAKESHORE.  
 
WHILE QUIET AND DRY WEATHER WILL PERSIST IN THIS BLOCKED PATTERN  
THROUGH THE REST OF THE WORK WEEK, THIS PATTERN WILL BEGIN TO  
BREAK LATE IN THE WEEK AS A WESTERN TROUGH (AND/OR POTENTIAL CUT-  
OFF LOW) BEGINS TO SLIDE EASTWARD TOWARDS THE GREAT LAKES. THE NET  
RESULT OF THIS WILL BE INCREASING CHANCES FOR PERIODIC SHOWERS  
AND THUNDERSTORMS FOR THIS WEEKEND INTO EARLY NEXT WEEK. THIS  
WILL ALSO BE PAIRED WITH COOLER MORE SEASONABLE TEMPERATURES IN  
THE 70S.  
 
KJB  
 

 
   
AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/
 
 
ISSUED AT 1221 PM CDT MON SEP 15 2025  
 
NO SIGNIFICANT WEATHER CONCERNS THROUGH THE PERIOD AS HIGH  
PRESSURE REMAINS IN CONTROL. EAST TO NORTHEAST WINDS OF LESS  
THAN 10 KT WILL CONTINUE THROUGH THE AFTERNOON THEN DIMINISH TO  
A FEW KTS THIS EVENING. EXPECT THAT THE WIND DIRECTION WILL  
BECOME SOMEWHAT VARIABLE FROM NORTH TO EAST OR EAST-SOUTHEAST  
TONIGHT. STEADIER EAST TO EAST-SOUTHEAST WINDS WILL RETURN  
TOWARD MIDDAY TUESDAY.  
 
MDB  
 

 
   
LOT WATCHES/WARNINGS/ADVISORIES
 
 
IL...NONE.  
IN...NONE.  
LM...NONE.  
 

 
 

 
 
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