494  
FXUS63 KILX 120452  
AFDILX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE LINCOLN IL  
1152 PM CDT THU SEP 11 2025  
   
KEY MESSAGES
 
 
- AN EXTENDED PERIOD OF WELL ABOVE NORMAL TEMPERATURES CONTINUES  
ACROSS CENTRAL AND SOUTHEAST IL THROUGH AT LEAST NEXT THURSDAY.  
 
- LITTLE TO NO PRECIPITATION IS EXPECTED DURING THE NEXT 7 DAYS,  
INTRODUCING THE RISK FOR FLASH DROUGHT CONDITIONS THROUGH MID  
SEPTEMBER FOR CENTRAL AND SOUTHERN IL.  
 

 
   
DISCUSSION
 
 
ISSUED AT 230 PM CDT THU SEP 11 2025  
 
MID AFTERNOON SURFACE MAP SHOWS 1027-1029 MB HIGH PRESSURE OVER  
JAMES BAY CANADA AND RIDGING SOUTHWARD INTO THE GREAT LAKES  
REGION, AND INFLUENCING CENTRAL/NE IL WITH WEAK EAST TO NE FLOW.  
SCATTERED CUMULUS CLOUDS WERE OVER CENTRAL AND EASTERN PARTS OF  
CWA WITH FEW CUMULUS CLOUDS FROM PEORIA AND SPRINGFIELD WEST. WARM  
TEMPS WERE IN THE LOW TO MID 80S OVER CENTRAL/SE IL WITH OLNEY AT  
88F AND MT CARMEL AIRPORT IN SOUTHERN LAWRENCE COUNTY AT 89F.  
DEWPOINTS WERE IN THE 50S OVER CENTRAL IL 60-65F IN SOUTHEAST IL.  
ALOFT AN OMEGA BLOCK PATTERN WAS OCCURRING OVER US, WITH A STRONG  
MID/UPPER LEVEL RIDGE WAS OVER THE CENTRAL PLAINS WITH UPPER  
LEVEL TROF OVER THE ATLANTIC STATES AND A STRONGER UPPER LEVEL  
TROF/LOW OVER THE PACIFIC STATES (A 572 DECAMETER 500 MB LOW WAS  
NEAR THE OR/CA/NV BORDER).  
 
BROAD SURFACE HIGH PRESSURE RIDGE TO SLOWLY SHIFT EASTWARD INTO  
QUEBEC, NEW ENGLAND AND INTO THE CENTRAL APPALACHIANS ON FRIDAY  
WITH SOUTH TO SSE FLOW DEVELOPING OVER CENTRAL IL. STRONG UPPER  
LEVEL RIDGE TO ALSO BUILD MORE OVER IL AS 500 MB HEIGHTS RISE  
ABOVE 588 DECAMETERS. DIURNALLY DRIVEN CU FIELD TO DISSIPATE  
AFTER DUSK WITH FAIR WX EXPECTED AGAIN TONIGHT. LATEST CAMS HINT  
AT SOME FOG DEVELOP OVER NORTHEAST IL, MAINLY NE OF CWA AND FOG  
MORE PREVALENT CLOSER TO LAKE MI AND MARINE LAYER. FAR SOUTHERN  
IL ALSO COULD SEE PATCHY FOG DEVELOP OVERNIGHT WHILE MOST OF OUR  
CWA SHOULD NOT SEE TOO MUCH FOG. LACON AND ROBINSON HAD PATCHY FOG  
EARLY THIS MORNING WITH VSBYS 1-2 MILES AND MAY SEE A FEW SPOTS  
WITH SIMILAR CONDITIONS IN EASTERN IL. LOWS OVERNIGHT IN THE UPPER  
50S TO AROUND 60F. HOT ON FRIDAY WITH HIGHS AROUND 90F TO LOWER  
90S FROM PEORIA TO EFFINGHAM WEST. FEW TO SCATTERED CUMULUS CLOUDS  
TO DEVELOP BY MIDDAY FRI INTO FRI AFTERNOON WITH MORE CUMULUS  
CLOUDS EXPECTED OVER THE IL RIVER VALLEY/WESTERN CWA BY FRI  
AFTERNOON.  
 
THE STRONGER UPPER LEVEL RIDGE NEAR IL THIS WEEKEND INTO MIDDLE OF  
NEXT WEEK TO CONTINUE THE HEAT WAVE WITH HIGHS IN THE LOW TO MID  
90S SATURDAY THROUGH WEDNESDAY, AND LIKELY LOWER 90S YET NEXT  
THURSDAY. CONTINUED TO BLEND THE RAW NBM HIGH TEMPERATURES FROM  
FRIDAY THROUGH WED WITH THE 50TH PERCENTILE NBM TO BRING SOME OF  
THE ERRONEOUSLY HIGH VALUES DOWN. TEMPERATURES REMAIN ELEVATED  
THROUGH MUCH OF NEXT WORK WEEK, THOUGH SHOULD COME DOWN SLIGHTLY  
LATE NEXT WEEK.  
 
MODELS BEGIN TO DIVERGE WITH CONVECTION CHANCES STARTING THIS  
WEEKEND AS SHORT WAVES START RIDGING OVER TOP OF THE SUBTROPICAL  
RIDGE AND QUESTION IS HOW FAR SOUTH CONVECTION CHANCES CAN GET AND  
COVERAGE. OVERNIGHT FRIDAY NIGHT COULD SEE ISOLATED CONVECTION  
MOVE OVER NORTHERN IL THOUGH MOST OF THIS CONVECTION APPEARS TO  
MISS CENTRAL IL. BUT MORE MODEL SOLUTIONS SHOW SOME CONVECTION  
CHANCES OVER PARTS OF CWA ESPECIALLY NE CWA ON SATURDAY AND SAT  
NIGHT. GFS STILL APPEARS TOO WET OVER AREA THIS WEEKEND AND NBM  
KEEPS POPS CLOSER TO 10% OVER MUCH OF AREA. CUTOFF LOWS MOVING  
OVER THE MID AND SOUTHERN ATLANTIC STATES BY MID WEEK WITH ANOTHER  
CUTOFF LOW MOVING INTO THE CENTRAL AND NORTHERN HIGH PLAINS TO  
KEEP BETTER CONVECTION CHANCES SE OF IL AND TO OUR NW. MAYBE A  
BETTER CHANCE OF NEEDED CONVECTION LATER NEXT WEEK AROUND NEXT  
FRIDAY.  
 
THE CLIMATE PREDICTION CENTER (CPC) 6-10 DAY OUTLOOK FOR SEP 17-21  
HAS 70-80% CHANCE OF ABOVE NORMAL TEMPERATURE OVER IL. CPC 8-14  
DAY OUTLOOK FOR SEP 19-25 HAS 50-60% CHANCE OF ABOVE NORMAL  
TEMPERATURES OVER IL. SO WE MAY NEED TO KEEP OUR AIR CONDITIONING  
UNITS GOING THIS MONTH.  
 
07  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)  
ISSUED AT 1152 PM CDT THU SEP 11 2025  
 
ANOTHER SET OF VFR TAFS WITH MOSTLY CLEAR SKIES AND EAST TO  
SOUTHEAST WINDS UNDER 10 KT.  
 
25  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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