112  
FXUS63 KILX 081941  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
241 PM CDT MON JUN 8 2026  
   
KEY MESSAGES
 
 
- A HEAVY RAIN THREAT WILL PERSIST THROUGH THIS EVENING,  
CONTINUING INTO THE OVERNIGHT HOURS SOUTH OF I-72/DANVILLE.  
RATES OF TWO INCHES PER HOUR OR GREATER MAY LEAD TO LOCALIZED  
FLASH FLOODING.  
 
- THE COMBINATION OF HEAT AND HUMIDITY WILL LEAD TO HEAT INDEX  
VALUES PEAKING BETWEEN 95 AND 105 DEGREES ON TUESDAY AND  
WEDNESDAY. THOSE SENSITIVE TO HEAT SHOULD TAKE EXTRA  
PRECAUTIONS.  
 
- THE THREAT FOR SEVERE WEATHER WILL INCREASE THROUGH THIS  
WEEK, PEAKING IN THE LATE WEDNESDAY NIGHT-THURSDAY TIME FRAME.  
 
 

 
   
DISCUSSION
 
 
ISSUED AT 241 PM CDT MON JUN 8 2026  
 
NEAR RECORD PRECIPITABLE WATER VALUES OF JUST OVER 2" ALONG WITH  
AN APPROACHING UPPER LOW ARE DRIVING A HEAVY RAIN THREAT TODAY,  
WITH MULTIPLE REPORTS OF 2"/HOUR RAIN RATES. EAST CENTRAL IL  
WILL SEE THE GREATEST THREAT FOR HEAVY RAIN OVER THE NEXT FEW  
HOURS. AN MCV MOVING OUT OF SOUTHEAST MO MAY LEAD TO  
THUNDERSTORM DEVELOPMENT IN PORTIONS OF SOUTHEASTERN IL THAT  
HAVE YET TO SEE MUCH ACTIVITY. SOME WILL SEE A BRIEF BREAK THIS  
AFTERNOON, BUT WITH MORE SHOWERS/STORMS CAPABLE OF HEAVY  
RAINFALL MOVING IN FROM THE WEST WE ANTICIPATE THE FLOOD THREAT  
TO PERSIST THROUGH AT LEAST THIS EVENING. A FEW CAMS DEPICT A  
CONVECTIVE COMPLEX WITH AN ASSOCIATED MCV MOVING ACROSS MO AND  
WEAKENING DURING THE OVERNIGHT HOURS. THE SOUTHERN PORTION OF  
THE FLOOD WATCH HAS BEEN EXTENDED TO 7 AM TO ACCOUNT FOR THIS  
POSSIBILITY, AS WELL AS TO ACCOUNT FOR THE PERSISTENT NEAR  
RECORD PW VALUES.  
 
THE COMBINATION OF HEAT AND HUMIDITY THEN BECOME A CONCERN FOR  
TUESDAY AND WEDNESDAY. HEAT INDEX VALUES IN THE MID 90S UP TO  
A FEW DEGREES OVER 100 ARE ANTICIPATED. PARTICULARLY FOLLOWING  
THE EXTENDED PERIOD OF DRY AND COOL CONDITIONS EXPERIENCED  
TOWARD THE END OF MAY/IN THE FIRST WEEK OF JUNE, THIS PERIOD OF  
HEAT AND HUMIDITY COULD HAVE MORE IMPACT THAN USUAL. ON TUESDAY,  
A WEAK MOISTURE BOUNDARY MAY TRIGGER ISOLATED THUNDERSTORMS BUT  
LITTLE RELIEF FROM THE HEAT WILL PROBABLY RESULT. INSTABILITY IS  
QUITE STRONG, BUT WITH SHEAR LIMITED THE SEVERE THREAT SHOULD BE  
LIMITED AS WELL. THE MAIN CONCERN WOULD BE ISOLATED STRONG TO  
SEVERE WIND GUSTS.  
 
THE SEVERE WEATHER THREAT IS FORECAST TO INCREASE LATER IN THE  
WEEK FOR CENTRAL AND SOUTHEAST ILLINOIS. LATE WEDNESDAY NIGHT  
INTO THURSDAY MORNING, SEVERE STORMS COMING OUT OF THE UPPER  
MISSISSIPPI VALLEY ARE FORECAST TO WEAKEN AS THEY MOVE TOWARD  
CENTRAL ILLINOIS. THE GREATER THREAT IS ANTICIPATED ON THURSDAY  
AFTERNOON/EVENING, WITH SPC DELINEATING A 30% CONTOUR  
APPROXIMATELY NEAR AND WEST OF I-55.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
 
 
ISSUED AT 1246 PM CDT MON JUN 8 2026  
 
PRIMARY BAND OF HEAVY RAIN AND THUNDERSTORMS IS NOW WORKING ITS  
WAY THROUGH KBMI-KMTO, AND SHOULD REACH KCMI WITHIN THE HOUR.  
THREATS ARE LIGHTNING, RAIN RATES IN EXCESS OF 1" PER HOUR WITH  
IFR OR LOWER VISIBILITIES, AND SOME GUSTY SOUTH WINDS. ANOTHER  
ROUND OF SCATTERED THUNDERSTORMS NOW IN WESTERN ILLINOIS IS  
ANTICIPATED TO AFFECT THE TAF SITES DURING THE MID TO LATE  
AFTERNOON HOURS. MVFR TO PERHAPS IFR CEILINGS ARE FORECAST TO  
DEVELOP OVERNIGHT, PRIMARILY EAST OF A LINE FROM KPIA-KSPI.  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH UNTIL 1 AM CDT TUESDAY FOR ILZ027>031-036>038-  
041>046-053-055-057.  
FLOOD WATCH UNTIL 1 AM CDT TUESDAY FOR ILZ040-047>052-054-056-  
061>063-066>068-071>073.  
 

 
 

 
 
KEY MESSAGES...AAT  
DISCUSSION...AAT  
AVIATION...AAT  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab IL Page Main Text Page