393  
FXUS63 KILX 130456  
AFDILX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE LINCOLN IL  
1156 PM CDT FRI SEP 12 2025  
   
KEY MESSAGES
 
 
- AN EXTENDED PERIOD OF WELL ABOVE NORMAL TEMPERATURES CONTINUES  
ACROSS CENTRAL AND SOUTHEAST IL THROUGH NEXT FRIDAY WITH HIGHS  
IN THE UPPER 80S TO MID 90S EXPECTED THROUGH AT LEAST THURSDAY.  
 
- ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE NORTH OF I-74  
OVERNIGHT. THERE IS A 20-40% CHANCE OF SHOWERS AND THUNDERSTORMS  
THUNDERSTORMS NORTHEAST OF A PEORIA TO TERRE HAUTE LINE ON  
SATURDAY AND ALONG AND EAST OF HIGHWAY 51 DURING SATURDAY  
NIGHT. OTHERWISE MUCH OF AREA WILL SEE DRY CONDITIONS INTO THE  
MIDDLE OF NEXT WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 245 PM CDT FRI SEP 12 2025  
 
A WARM FRONT WAS OVER CENTRAL IOWA AND NORTHEAST MO, JUST SW OF  
IL AT MID AFTERNOON. PARTLY TO MOSTLY SUNNY SKIES PREVAILED OVER  
CENTRAL AND SOUTHEAST IL WITH MORE SCATTERED CUMULUS CLOUDS IN  
EASTERN IL EAST OF HIGHWAY 51, ALONG WITH SOME PASSING CIRRUS  
CLOUDS. WARM TEMPS WERE IN THE MID TO UPPER 80S WITH PITTSFIELD  
91F AND QUINCY 90F. DEWPOINTS WERE MOSTLY IN THE 50S WITH  
DEWPOINTS AROUND 60F IN WEST CENTRAL IL AND AT OLNEY. PW VALUES  
HAD RISEN TO 1.2-1.4 INCHES IN WEST CENTRAL IL CLOSER TO  
APPROACHING WARM FRONT. NEAREST CONVECTION WAS OVER CENTRAL IA  
AND FEW ISOLATED CELLS IN NORTH CENTRAL MO.  
 
LATEST CAMS SHOW MOST OF CONVECTION TONIGHT TO BE FOCUSED OVER  
THE UPPER MS RIVER VALLEY ON NOSE OF LOW LEVEL JET AS WARM FRONT  
LIFTS NE ACROSS CENTRAL IL DURING LATE EVENING AND OVERNIGHT. BUT  
SOME CAM MEMBERS LIKE HRRR AND FV3 SHOW ISOLATED CONVECTION  
DROPPING SE TOWARD I-74 LATE TONIGHT. SO ADDED SLIGHT POPS MAINLY  
AFTER 2 AM TONIGHT NORTH OF I-74. CAMS HAVE TRENDED FURTHER SOUTH  
WITH A CLUSTER OF CONVECTION DROPPING SSE INTO NORTHEAST AND EAST  
CENTRAL IL ON SAT MORNING AS IT WEAKENS. COULD SEE ISOLATED  
CONVECTION DEVELOP ALONG LINGERING OUTFLOW BOUNDARIES DURING SAT  
AFTERNOON FURTHER SOUTH INTO CENTRAL IL AS MUCAPES RISE TO  
1500-3000 J/KG AND 0-6 KM BULK SHEAR VALUES ARE 25-30 KTS IN  
NE/EASTERN CWA. MORE CLUSTERS OF CONVECTION PROJECTED TO DROP  
SOUTHWARD OVER IN AND POSSIBLY INTO EASTERN IL, ESPECIALLY EAST OF  
I-57 DURING SAT NIGHT ESPECIALLY OVERNIGHT HOURS. SPC ADDED  
MARGINAL RISK OF SEVERE STORMS FOR WIND AND HAIL NE OF A HENRY TO  
BLOOMINGTON TO CHARLESTON LINE ON SATURDAY AND SAT NIGHT.  
 
LOWS OVERNIGHT IN THE LOW TO MID 60S WITH AREAS NEAR THE INDIANA  
BORDER AROUND 60F. HIGHS SAT IN THE UPPER 80S AND LOWER 90S,  
COOLEST NE CWA AND WARMEST FROM SPRINGFIELD SW WHERE HIGHS  
APPROACHING 95F. HIGHS IN THE LOW TO MID 90S ON SUNDAY WITH MID  
90S MORE COMMON ESPECIALLY FROM I-57 WEST WHERE MORE SUNSHINE  
EXPECTED. HEAT INDICES TO PEAK AROUND 100F SUNDAY AFTERNOON OVER  
THE IL RIVER VALLEY WHERE DEWPOINTS REACH UPPER 60S TO NEAR 70F.  
 
A STRONG SUBTROPICAL UPPER LEVEL RIDGE EXTENDING FROM TEXAS INTO  
THE CENTRAL/EASTERN PLAINS WILL BE OVER IL FROM THIS WEEKEND INTO  
MIDDLE OF NEXT WEEK, KEEPING IT HOT WITH HIGHS IN THE LOW TO MID  
90S MON THROUGH WED AND UPPER 80S/LOWER 90S THU. CONVECTION  
CHANCES WILL BE LOW SUNDAY THROUGH WED NIGHT, WITH SOME UPTICK IN  
CONVECTION CHANCES THU/FRI AS UPPER LEVEL TROF APPROACHES FROM THE  
WEST.  
 
THE CLIMATE PREDICTION CENTER (CPC) 6-10 DAY OUTLOOK FOR SEP 18-22  
HAS 60-70% CHANCE OF ABOVE NORMAL TEMPERATURES OVER CENTRAL/SE IL.  
CPC 8-14 DAY OUTLOOK FOR SEP 20-26 HAS 55-60% CHANCE OF ABOVE  
NORMAL TEMPS OVER CENTRAL/SOUTHEAST IL. SO THE LATE SUMMER HEAT  
LOOKS TO CONTINUE FOR AWHILE.  
 
07  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)  
ISSUED AT 1156 PM CDT FRI SEP 12 2025  
 
VFR FOR MOST CENTRAL IL TERMINALS THROUGH THE PERIOD WITH  
SOUTHEAST TO SOUTH WINDS NEAR/UNDER 10 KT. HIGH RESOLUTION MODELS  
SHOW AN AREA OF THUNDERSTORMS DEVELOPING OVER NORTHERN IL THIS  
MORNING, DROPPING SOUTHEAST INTO EAST CENTRAL IL THIS AFTERNOON.  
CONFIDENCE ON TIMING/PLACEMENT OF STORMS IS LOW AT THIS RANGE, SO  
WENT WITH PROB30 GROUP FOR TSRA AT KBMI-KCMI AND WILL WATCH TRENDS  
FOR REFINEMENT ON LATER FORECASTS.  
 
25  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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