788  
FXUS63 KILX 262333  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
633 PM CDT THU MAR 26 2026  
   
KEY MESSAGES
 
 
- AN ENHANCED RISK FOR SEVERE WEATHER EXISTS ALONG AND NORTHEAST  
OF A CANTON TO SHELBYVILLE LINE THROUGH THIS EVENING. THE  
PRIMARY RISKS WILL BE DAMAGING WIND GUSTS IN EXCESS OF 70MPH,  
HAIL LARGER THAN 2 INCHES IN DIAMETER, AND A FEW TORNADOES  
 
- AFTER RECORD-BREAKING WARMTH TODAY, TEMPERATURES WILL PLUNGE  
INTO THE MIDDLE TO UPPER 20S BY FRIDAY NIGHT.  
 

 
   
DISCUSSION
 
 
ISSUED AT 250 PM CDT THU MAR 26 2026  
 
SEVERE WEATHER THIS EVENING...  
 
19Z/2PM SURFACE ANALYSIS SHOWS A COLD FRONT EXTENDING FROM  
SOUTHERN LAKE MICHIGAN SOUTHWESTWARD TO THE IOWA/MISSOURI STATE  
LINE. RECORD-BREAKING WARMTH PREVAILS WITHIN THE WARM SECTOR  
WITH CURRENT READINGS IN THE MIDDLE TO UPPER 80S ACROSS CENTRAL  
ILLINOIS. MEANWHILE NORTH OF THE FRONT, TEMPERATURES HAVE  
DROPPED INTO THE 50S IN NORTHERN ILLINOIS.  
 
19Z MESOANALYSIS INDICATES MLCAPES OF 1000-1500J/KG POOLING  
SOUTH OF THE FRONT: HOWEVER, 150-200J/KG OF MLCIN HAS THUS FAR  
CAPPED ANY CONVECTIVE DEVELOPMENT. VISIBLE SATELLITE IMAGERY IS  
SHOWING A CU FIELD FORMING ALONG/NORTH OF A MACOMB TO PONTIAC  
LINE...AND THIS WILL BE THE AREA TO WATCH FOR THUNDERSTORM  
INITIATION OVER THE NEXT 1-3 HOURS. WHILE CAM TIMING STILL  
VARIES SLIGHTLY, A CONSISTENT SIGNAL FROM THE HRRR AND RRFS  
SUGGESTS THE FIRST CLUSTER OF STORMS FORMING NORTHEAST OF PEORIA  
BETWEEN 21Z/4PM AND 22Z/5PM...THEN TRACKING E/SE JUST NORTH OF  
THE I-74 CORRIDOR THROUGH 00Z/7PM. GIVEN THE POOL OF HIGH CAPES,  
STEEP MID-LEVEL LAPSE RATES, AND 0-6KM BULK SHEAR OF 50-60KT,  
THE STAGE WILL BE SET FOR RAPID DEVELOPMENT ONCE THE CAP IS  
BROKEN IMMEDIATELY ALONG THE APPROACHING BOUNDARY. THE INITIAL  
STORM CLUSTER WILL THEREFORE POSE A VERY LARGE HAIL RISK  
(POTENTIALLY GREATER THAN 2 INCHES IN DIAMETER), AS WELL AS A  
TORNADO RISK IF IT REMAINS CLOSE TO THE BOUNDARY AS ADVERTISED.  
 
ONCE THE LATE AFTERNOON STORM CLUSTER PUSHES INTO INDIANA,  
ADDITIONAL CONVECTION WILL FIRE FURTHER WEST ALONG THE TRAILING  
COLD FRONT THIS EVENING. THERE WILL BE A NARROW WINDOW BETWEEN  
ABOUT 6PM AND 10PM WHEN FAVORABLE INSTABILITY/SHEAR PROFILES  
WILL CONTINUE TO SUPPORT ALL STORM HAZARDS BEFORE DAYTIME  
INSTABILITY WANES AND THE SEVERE THREAT DIMINISHES. IT APPEARS  
THE MOST FAVORED LOCATION FOR SEVERE THIS EVENING WILL BE ALONG  
AND NEAR THE I-72 CORRIDOR...BEFORE THE STORMS BEGIN TO LOSE  
THEIR VIGOR AS THEY SINK SOUTHWARD TO THE I-70 BY MIDNIGHT OR  
SHORTLY AFTERWARDS.  
 
SHARPLY FALLING TEMPERATURES...  
 
ONCE THE COLD FRONT PASSES, STRONG N/NE WINDS GUSTING 30-35MPH  
WILL BRING A MUCH COOLER AIRMASS SOUTHWARD INTO CENTRAL ILLINOIS  
TONIGHT. LOW TEMPERATURES WILL BOTTOM OUT IN THE LOWER TO MIDDLE  
30S ACROSS MUCH OF THE KILX CWA, WITH LOWER 40S SOUTH OF I-70.  
FRIDAY WILL START OUT AS A CLOUDY, BREEZY, AND VERY CHILLY  
DAY...BEFORE AT LEAST PARTIAL SUNSHINE RETURNS BY AFTERNOON.  
HIGHS WILL ONLY REACH THE UPPER 40S TO AROUND 50 DEGREES. AS HIGH  
PRESSURE BUILDS INTO THE REGION, SKIES WILL CLEAR AND WINDS WILL  
BECOME LIGHT/VARIABLE FRIDAY NIGHT. EXCELLENT RADIATIONAL  
COOLING OF THE DRY AIRMASS WILL ALLOW OVERNIGHT LOWS TO PLUNGE  
INTO THE MIDDLE TO UPPER 20S...WHICH COULD POSE A RISK TO TENDER  
SPRING VEGETATION THAT HAS EMERGED 2-3 WEEKS EARLY.  
 
WARMER AND WETTER NEXT WEEK...  
 
AFTER A BRIEF CHILL TO START THE WEEKEND, TEMPERATURES WILL  
QUICKLY REBOUND INTO THE 60S ON SUNDAY...THEN BACK INTO THE 80S  
BY NEXT MONDAY AND TUESDAY. THE PATTERN WILL ALSO BECOME  
DECIDEDLY MORE UNSETTLED AS A FRONTAL BOUNDARY WAVERS IN THE  
REGION FOR SEVERAL DAYS. WHILE IT IS STILL TOO EARLY TO PINPOINT  
ANY SPECIFIC SEVERE WEATHER RISK AT THAT TIME RANGE, THE  
COLORADO STATE MACHINE LEARNING ALGORITHM IS HIGHLIGHTING LOW  
PROBABILITIES (5-15% CHANCE) FOR SEVERE ACROSS PORTIONS OF  
ILLINOIS MONDAY THROUGH THURSDAY. THE CURRENT FORECAST FEATURES  
DAILY RAIN CHANCES, WITH THE GREATEST CHANCE (60%) FOCUSED ON  
THURSDAY. STAY TUNED TO LATER FORECASTS AS DETAILS BECOME  
CLEARER.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z SATURDAY/
 
 
ISSUED AT 632 PM CDT THU MAR 26 2026  
 
THE INITIAL CLUSTERS OF THUNDERSTORMS ASSOCIATED WITH A PASSING  
COLD FRONT ARE CURRENTLY ONGOING FROM NEAR KBMI/KDEC EASTWARD  
TO THE INDIANA BORDER. HAVE THEREFORE GONE WITH THUNDER IN THE  
KCMI TAF IMMEDIATELY. FURTHER WEST, ONLY SHOWERS ARE OCCURRING:  
HOWEVER, ALL CAM GUIDANCE SUGGESTS CONVECTIVE DEVELOPMENT WITHIN  
THE NEXT 1-3 HOURS. AS SUCH, HAVE MAINTAINED PREDOMINANT THUNDER  
AT ALL SITES AFTER 01Z/02Z...WITH A 2-3 HOUR WINDOW OF  
POTENTIALLY SEVERE THUNDER/HAIL. MODELS CONTINUE TO SHOW THE  
WIDESPREAD CONVECTION SINKING SOUTHWARD LATER THIS EVENING, SO  
HAVE ENDED THUNDER AT KPIA BY 06Z...THEN FURTHER SOUTH TO THE  
I-72 TERMINALS BY 08Z. ONCE THE FRONT PASSES, WINDS SWITCH TO NE  
AND GUST 30-35KT. THE GUSTY WINDS WILL CONTINUE THROUGH THE  
NIGHT AND INTO FRIDAY MORNING BEFORE GRADUALLY DECREASING BY  
FRIDAY AFTERNOON. IN ADDITION, LOW CLOUDS CURRENTLY POISED  
UPSTREAM ACROSS WISCONSIN/NORTHERN ILLINOIS WILL SPILL SOUTHWARD  
TONIGHT. HRRR/RAP INDICATE MVFR CEILINGS ARRIVING BY MID-  
EVENING, THEN LINGERING UNTIL ABOUT MIDDAY FRIDAY.  
 

 
   
CLIMATE
 
 
ISSUED AT 125 AM CDT WED MAR 25 2026  
 
FORECAST TEMPERATURES ON THURSDAY MAY EXCEED MARCH RECORDS IN  
SOME AREAS.  
 
MAR 26 RECORD MARCH RECORD  
CHARLESTON.... 84 (1907) 89 (3/24/1929 AND 3/22/2026)  
DECATUR....... 83 (1907) 89 (3/24/1929)  
JACKSONVILLE.. 83 (1950) 91 (3/21/1907)  
LINCOLN....... 83 (1991) 86 (3/29/1985 AND 3/30/1986)  
NORMAL........ 83 (2007) 88 (3/21/1907)  
OLNEY......... 85 (1907) 89 (3/24/1910 AND 3/24/1929)  
PEORIA........ 82 (1907/1991) 87 (3/21/1907)  
SPRINGFIELD... 81 (1991) 91 (3/21/1907)  
URBANA........ 81 (1907) 85 (3/21/1907 AND 3/24/1910)  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
BLOWING DUST ADVISORY UNTIL 9 PM CDT THIS EVENING FOR ILZ036-  
040>057-061>063.  
 

 
 

 
 
KEY MESSAGES...BARNES  
DISCUSSION...BARNES  
AVIATION...BARNES  
CLIMATE...GEELHART  
 
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