996  
FXUS63 KILX 222342  
AFDILX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE LINCOLN IL  
642 PM CDT MON SEP 22 2025  
   
KEY MESSAGES
 
 
- THE UNSETTLED PATTERN WILL CONTINUE WITH DAILY RAIN CHANCES  
THROUGH AT LEAST THURSDAY. THE BEST CHANCE OF RAIN IS TUESDAY  
NIGHT AND WEDNESDAY (60-80% SOUTHEAST OF THE IL RIVER). NEW  
RAINFALL AMOUNTS OF OVER 2" ARE POSSIBLE, WITH THE BEST CHANCE  
BEING SOUTHEAST OF I-70 (30-45%).  
 
- FOG DEVELOPMENT, SOME OF WHICH COULD BE DENSE, IS LIKELY  
OVERNIGHT INTO THE TUESDAY MORNING COMMUTE. THE BEST CHANCE FOR  
VISIBILITY BELOW A HALF MILE IS FROM I-55 SOUTHEAST (50-70%).  
 

 
   
DISCUSSION
 
 
ISSUED AT 245 PM CDT MON SEP 22 2025  
 
RADAR MOSAIC SHOWS THE MAIN AREA OF SHOWERS AND ISOLATED  
THUNDERSTORMS HAD PASSED EAST AND SOUTH OF IL WITH SCATTERED  
CONVECTION IN FAR SOUTHEAST/SOUTHERN IL, SE OF A BLOOMINGTON IN  
TO MARION IL LINE. A FEW ISOLATED LIGHT SHOWERS WERE EAST OF I-55,  
OTHERWISE MUCH OF CWA IS NOW DRY. SOME SUNSHINE WAS APPEARING  
THROUGH THE LOW/MID CLOUDS NW OF A TAYLORVILLE TO DECATUR TO  
CHAMPAIGN WHILE NEARLY OVERCAST MVFR CLOUDS 1-2K FT LINGERED IN  
SOUTHEAST IL.  
 
ISOLATED SHOWERS POSSIBLE INTO EARLY EVENING IN EASTERN IL AND  
LATE TONIGHT NORTH OF A GALESBURG TO LACON LINE AS CONVECTION  
CHANCES INCREASE OVER NORTHERN IL DURING TONIGHT. LATEST CAMS SHOW  
FOG DEVELOPING IN SOUTHEAST IL EARLY OVERNIGHT AND SPREADING  
NORTHWARD INTO CENTRAL IL DURING THE OVERNIGHT AND LINGERING INTO  
MID TUE MORNING. RAP AND HRRR SHOW MORE WIDESPREAD FOG BY LATE  
TONIGHT FROM I-72 SOUTH AND HREF HAS 50-70% CHANCE OF VSBYS BELOW  
1/2 MILE IN THIS AREA, SO DENSE FOG IS LOOKING MORE LIKELY OVER  
SOUTHERN HALF OF CWA. MAY EVENTUALLY NEED A DENSE FOG ADVISORY  
FROM I-72 SOUTH. ALSO SEEING PATCHY FOG DEVELOPING UP THE IL  
RIVER VALLEY LATE TONIGHT/EARLY TUE MORNING, THOUGH MID AND HIGH  
CLOUDS INCREASING OVER NORTHERN/NW CWA TOWARD DAWN MAY LIMIT  
EXTENT OF FOG. LOWS OVERNIGHT IN THE LOWER 60S, WITH MID 60S SE OF  
I-70.  
 
A DEVELOPING UPPER LEVEL LOW NEAR THE CO/KS BORDER LATE TUE TO  
HAVE SOME SHORT WAVES EJECTING EASTWARD INTO CENTRAL IL LATE TUE  
AFTERNOON AND TUE NIGHT AND WILL SEE INCREASING CHANCES OF  
CONVECTION OVER AREA LATER TUE INTO TUE NIGHT. ALSO AN OUTFLOW  
BOUNDARY FROM CONVECTION IN SOUTHERN WI TO MOVE INTO NORTHERN CWA  
AND COULD DEVELOP ITS OWN CONVECTION DURING TUE AFTERNOON AND A  
FEW CELLS COULD BECOME STRONG. SPC DAY2 OUTLOOK DOES NOT HAVE A  
MARGINAL RISK OF SEVERE STORMS OVER CENTRAL/SE IL THOUGH WILL NEED  
TO MONITOR NORTHERN CWA FOR TUE AFTERNOON INTO EARLY TUE EVENING.  
WARMER HIGHS TUE IN THE LOWER 80S AND STILL MUGGY WITH DEWPOINTS  
IN THE UPPER 60S.  
 
THE CUTOFF LOW AND TROF TO MOVE INTO MO BY LATE WED AND BRINGING  
OUR BEST CHANCES OF MORE WIDESPREAD SHOWERS AND A FEW  
THUNDERSTORMS TUE NIGHT AND WED WITH POPS OF 60-80% SE OF THE IL  
RIVER. THE HEAVIEST RAINS APPEARS TO SET UP OVER SOUTHERN CWA WED  
INTO THU EVENING WHEN 1-2 MORE INCHES OF RAIN POSSIBLE. AREAS  
SOUTH OF I-70 HAVE A 30-45% CHANCE OF SEEING OVER 2 INCHES OF  
RAIN. AS BEEN THE CASE THE PAST FEW DAYS, A FEW SPOTS COULD SEE  
LOCALLY 3-5 INCHES OVER SOUTHERN CWA BUT THIS WILL BE MORE  
ISOLATED IF IT OCCURS. WPC HAS MUCH OF CENTRAL AND SE CWA IN  
MARGINAL RISK OF EXCESSIVE RAINFALL WED AND WED NIGHT (AND OVER  
SOUTHERN CWA TUE NIGHT). COOLER HIGHS IN THE MID 70S WED AND MID  
TO UPPER 70S THU. SURFACE LOW APPEARS TO PASS SOUTH OF CWA WED AND  
WED NIGHT NEAR OR JUST NORTH OF THE OHIO RIVER WHILE UPPER LEVEL  
TROF AXIS MOVES EAST OF IL DURING THU AFTERNOON. HAVE CHANCES OF  
SHOWERS THU WITH HIGHEST POPS 30-40% IN EASTERN IL AND QPF  
AMOUNTS TO BE LIGHTER.  
 
MODELS HAVE TRENDED QUICKLY WITH MOVING UPPER LEVEL TROF EAST OF  
IL LATE THIS WORK WEEK AND MUCH OF AREA APPEARS DRIER THU NIGHT  
AND FRI AS UPPER LEVEL RIDGE BUILDING INTO THE CENTRAL ROCKIES AND  
CENTRAL PLAINS. WE KEPT SLIGHT CHANCE OF SHOWERS IN EASTERN IL  
THU EVENING. CUTOFF LOW STILL FORECAST TO BE OVER THE GULF COAST  
AND SOUTHEAST ATLANTIC STATES THIS WEEKEND WITH UPPER LEVEL  
RIDGING INTO IL, KEEPING US DRY AND WARMER. HIGHS IN THE LOW TO  
MID 80S SATURDAY THROUGH MONDAY.  
 
THE CLIMATE PREDICTION CENTER (CPC) 8-14 DAY OUTLOOK FOR SEP 30  
THROUGH OCT 6 HAS 55-60% CHANCE OF ABOVE NORMAL TEMPERATURES OVER  
CENTRAL AND SOUTHEAST IL. PRECIPITATION TRENDING NEAR NORMAL OR  
SLIGHTLY BELOW NORMAL OVER FAR NE AND EAST CENTRAL IL.  
 
07  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)  
ISSUED AT 641 PM CDT MON SEP 22 2025  
 
ALL SITES WILL START AS VFR WITH VERY FEW CLOUDS PRESENT ON  
SATELLITE LOOPS. HOWEVER, WITH MOSTLY CLEAR SKIES AND LIGHT WINDS,  
EXPECTED FOG TO DEVELOP ACROSS THE SOUTHEAST PARTS OF THE CWA AND  
THEN SPREAD NORTH AND NORTHWEST, REACHING SPI, DEC, AND CMI  
OVERNIGHT/TOWARD MORNING. CIGS AND VIS WILL DROP INTO IFR  
CATEGORIES FOR SEVERAL HOURS, BUT LIFR AS WELL FOR A SHORT AMOUNT  
OF TIME AS VIS LOWERS TO BELOW 1SM AND CIGS BELOW 1KFT. CONDITIONS  
IMPROVE LATER IN THE MORNING BU CIGS WILL BE MVFR INTO THE  
AFTERNOON. ALSO EXPECTED MORE STORMS TO DEVELOP TOMORROW AFTERNOON  
ACROSS THE AREA AS ANOTHER WAVE DROPS INTO THE AREA. WILL HAVE  
PROB30, BUT STORMS SHOULD BE POSSIBLE AT PIA AND BMI FIRST, AND  
THEN AT SPI, DEC, CMI FOR LAST PART OF AFTERNOON. WINDS WILL BE  
LIGHT THROUGH THE PERIOD.  
 
AUTEN  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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