344  
FXUS63 KILX 111659  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
1159 AM CDT SUN OCT 11 2026  
   
KEY MESSAGES
 
 
- NEAR-RECORD WARMTH CAN BE EXPECTED TODAY AND MONDAY, WITH  
AFTERNOON HIGH TEMPERATURES IN THE 80S TODAY AND UPPER 80S TO  
LOWER 90S MONDAY. TUESDAY LOOKS EQUALLY WARM SOUTH OF I-72.  
 
- AN EXTENDED PERIOD OF RAIN CHANCES IS ON TRACK TUESDAY NIGHT  
THROUGH THURSDAY. THERE IS A MARGINAL RISK FOR SEVERE  
THUNDERSTORMS IN WEST-CENTRAL IL TUESDAY EVENING, OTHERWISE  
SEVERE WEATHER POTENTIAL APPEARS LOW AT THIS POINT.  
 
- COLDER AIR WILL ARRIVE NEXT WEEKEND, ALTHOUGH THE AMOUNT OF  
COOLING REMAINS UNCERTAIN. PATCHY FROST COULD DEVELOP SATURDAY  
NIGHT AND SUNDAY NIGHT. OTHERWISE, TEMPERATURES ARE LIKELY TO  
BE BELOW NORMAL.  
 

 
   
DISCUSSION
 
 
ISSUED AT 240 AM CDT SUN OCT 11 2026  
 
SUNNY SKIES WILL RETURN TODAY AS HIGH PRESSURE BUILDS INTO CENTRAL  
IL. STRONG WARM ADVECTION BUILDING THIS RIDGE WILL RESULT IN  
HIGHS SURGING INTO THE MID 80S TODAY, JUST A FEW DEGREES FROM  
RECORD VALUES, AND INTO THE LOWER 90S MONDAY, EXCEEDING PREVIOUS  
RECORD HIGHS. A WEAK COLD FRONT WILL PUSH INTO THE AREA  
TUESDAY, BRINGING SOME MINOR COOLING TO AREAS NORTH OF I-72 AND  
A SLIGHT CHANCE FOR SHOWERS OR THUNDERSTORMS.  
 
MODELS ARE IN GOOD AGREEMENT THAT PRECIPITATION WILL DEVELOP TUESDAY  
NIGHT AS THE STALLED FRONTAL ZONE STRENGTHENS, A LOW LEVEL JET  
DEVELOPS, AND INCREASED GULF MOISTURE ARRIVES. 60 TO 80 PERCENT POPS  
ARE INCLUDED IN THE CURRENT FORECAST PACKAGE TUESDAY NIGHT INTO  
WEDNESDAY MORNING. PRECIPITATION AMOUNTS REMAIN UNCERTAIN, BUT 00Z  
GFS ADVERTISES AMOUNTS OVER AN INCH IN MUCH OF CENTRAL IL, WHILE 12Z  
ECMWF AND CANADIAN MODELS SHOW GENERALLY UNDER A HALF INCH. SEVERAL  
HUNDRED J/KG MUCAPE AND 30-40 KT BULK SHEAR APPEAR LIKELY TUESDAY  
EVENING IN A CORRIDOR EXTENDING FROM NORTHERN MO INTO WEST-CENTRAL  
IL AS 12Z ENSEMBLE DEPICTS 60+ PERCENT CHANCES FOR JOINT PROBABILITY  
OF SHEAR GREATER THAN 30 KTS AND MUCAPE GREATER THAN 500 J/KG, WHICH  
WOULD SUPPORT POTENTIAL FOR SEVERE STORMS. SPC HAS DESIGNATED A  
MARGINAL RISK FOR SEVERE STORMS IN THIS AREA.  
 
LATER IN THE WEEK, A CENTRAL ROCKIES LOW LOOKS TO EJECT EASTWARD AND  
MERGE WITH A CANADIAN LOW TO BRING ANOTHER 70 PERCENT CHANCE FOR  
SHOWERS AND THUNDERSTORMS THURSDAY.  
 
COLDER AIR FOLLOWING THURSDAY'S SYSTEM WILL ARRIVE FOR THE WEEKEND,  
HOWEVER THE TRAJECTORY OF THE COLDEST AIR REMAINS UNCERTAIN, WITH  
MODELS VARYING CONSIDERABLY. FOR CENTRAL IL, 12Z ENSEMBLES HAVE  
AROUND A 40 DEGREE SPREAD FOR SATURDAY AFTERNOON. CURRENT FORECAST  
REFLECTS ROUGHLY A MEDIAN VALUE, WITH HIGHS IN THE UPPER 50S AND  
LOWS IN THE UPPER 30S SATURDAY/SATURDAY NIGHT, BUT A POTENTIAL FOR  
FREEZING TEMPERATURES OR FROST WILL HAVE TO BE MONITORED FOR THIS  
TIME PERIOD.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z MONDAY/
 
 
ISSUED AT 1158 AM CDT SUN OCT 11 2026  
 
A COL AREA IS PROVIDING LIGHT AND VARIABLE WINDS TO MUCH OF  
CENTRAL ILLINOIS EARLY THIS AFTERNOON, BUT A SOUTHERLY GRADIENT  
WILL BEGIN TO SPREAD IN FROM THE WEST GRADUALLY THROUGH THE  
AFTERNOON AHEAD OF A DEVELOPING LOW OVER THE GREAT PLAINS. WINDS  
WILL BEGIN TO GUST TO AROUND 20KT BY LATE MONDAY MORNING.  
EXPECT VFR CONDITIONS THROUGH THE PERIOD WITH INCREASING MID AND  
HIGH CLOUDS.  
 

 
   
CLIMATE
 
 
ISSUED AT 612 AM CDT SUN OCT 11 2026  
 
RECORD HIGH TEMPERATURES FOR MONDAY AND TUESDAY:  
 
LOCATION MONDAY TUESDAY  
======== ======= =======  
BLOOMINGTON 88/1930 91/1899  
CHAMPAIGN 87/1962 86/1989  
CHARLESTON 89/1962 87/2017  
DECATUR 92/1962 90/1899  
JACKSONVILLE 88/1901 91/1899  
OLNEY 89/1928 93/1928  
PEORIA 87/2024 88/1899  
SPRINGFIELD 89/1962 88/1975  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
KEY MESSAGES...37  
DISCUSSION...37  
AVIATION...DEUBELBEISS  
CLIMATE...GEELHART  
 
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