295  
FXUS63 KILX 250115  
AFDILX  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE LINCOLN IL  
815 PM CDT THU JUL 24 2025  
   
KEY MESSAGES
 
 
- HEAT INDICES WILL LIKELY REACH 105 TO 110 DEGREES THIS AFTERNOON  
AND SOME CITIES RISING ABOVE 110 DEGREES. HEAT INDICES WILL  
REACH AROUND 105 DEGREES OR HIGHER SOUTH OF I-72 FRIDAY  
AFTERNOON.  
 
- ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED LATE THIS  
AFTERNOON AND TONIGHT, THAT MAY PRODUCE HEAVY RAIN LEADING TO  
LOCALIZED FLOODING. THERE IS A MARGINAL TO SLIGHT RISK OF SEVERE  
STORMS FROM I-72 NORTH FOR DAMAGING WIND GUSTS.  
 
- STORM CHANCES (40-60%) WILL LINGER INTO SATURDAY, WITH THE  
STRONGEST STORMS CAPABLE OF HEAVY RAIN AND GUSTY WINDS.  
 
- HOT AND HUMID WEATHER WILL STICK AROUND THROUGH TUESDAY, PEAKING  
SUNDAY INTO MONDAY WITH A 60-80% CHANCE FOR HEAT INDICES OVER  
105 BOTH DAYS.  
 

 
   
UPDATE
 
 
ISSUED AT 814 PM CDT THU JUL 24 2025  
 
INITIAL WAVE OF THUNDERSTORMS AND CORRESPONDING SEVERE WEATHER  
WATCH HAS ENDED ACROSS CENTRAL ILLINOIS, BUT ATTENTION TURNS BACK  
WEST LATE THIS EVENING AS THE NEXT ROUND OF STORMS IS CURRENTLY  
APPROACHING THE MISSISSIPPI RIVER IN NORTHEAST MISSOURI. THIS  
CLUSTER OF STORMS IS CURRENTLY SUB-SEVERE WITH SOME REPORTS OF  
30-40 KT GUSTS. DESPITE THE LATE TIMING AND INCREASING MLCIN LATE  
THIS EVENING, LATEST SPC MESOANALYSIS SUGGESTS THAT STRONG  
INSTABILITY TO AROUND 3000 J/KG MLCAPE REMAINS IN PLACE AHEAD OF  
THE APPROACHING STORMS WHILE EFFECTIVE SHEAR HAS INCREASED FROM  
EARLIER, NOW AROUND 25-30KT. GIVEN THE PARAMETER SPACE, WILL HAVE  
TO CONTINUE TO MONITOR FOR A COUPLE STRONG OR SEVERE STORMS OVER  
THE NEXT COUPLE OF HOURS, THOUGH DO ANTICIPATE STORMS TO  
EVENTUALLY WEAKEN WITH TIME DUE TO THE UNFAVORABLE DIURNAL TIMING.  
 
DEUBELBEISS  
 

 
   
DISCUSSION
 
 
ISSUED AT 230 PM CDT THU JUL 24 2025  
 
CONTINUED THE HEAT ADVISORY THROUGH 7 PM ACROSS CENTRAL IL FOR  
HEAT INDICES OF 105-110 AND LOCALLY HIGHER ABOVE 110F. EXTENDED  
HEAT ADVISORY FOR AREAS SOUTH OF I-72 FROM CHRISTIAN COUNTY  
EASTWARD TO EDGAR COUNTIES AND SOUTHWARD THROUGH 7 PM FRIDAY FOR  
HEAT INDICES AROUND 105F OR HIGHER FRIDAY AFTERNOON.  
 
CONVECTION DEVELOPING ALONG AN OUTFLOW BOUNDARY AT MID AFTERNOON  
FROM CHICAGO SW TO NEAR MACOMB IN VERY UNSTABLE AIR MASS WITH  
MLCAPES AROUND 3000 J/KG. THIS BOUNDARY MOVING SLOWLY SE INTO THE  
IL RIVER VALLEY AND TO SPAWN ADDITIONAL STRONG TO POTENTIALLY  
SEVERE STORMS LATE THIS AFTERNOON INTO AT LEAST MID EVENING.  
SLIGHT RISK OF SEVERE STORMS OVER NORTHERN/NE CWA LATE THIS  
AFTERNOON AND EVENING WITH DAMAGING WINDS THE MAIN HAZARD. LOCALLY  
HEAVY RAINS ALSO AS RISK AS WPC ERO HAS SLIGHT RISK OVER AREAS  
FROM I-72 TONIGHT. SEVERE THUNDERSTORM WATCH UNTIL 9 PM FOR STARK,  
PEORIA, TAZEWELL AND MCLEAN COUNTIES NORTHEAST.  
 
AN MCV OVER NW MO TO TRACK EASTWARD AND DEVELOP MORE CONVECTION  
INTO CENTRAL IL OVERNIGHT INTO FRIDAY ESPECIALLY NORTHERN/NW CWA.  
WPC HAS SLIGHT RISK OF EXCESSIVE RAINFALL AGAIN OVER MUCH OF  
CENTRAL IL FRI AND FRI NIGHT WHILE A FEW STRONG STORMS WITH GUSTY  
WINDS POSSIBLE TOO. HIGH HEAT AND HUMID TO CONTINUE FRIDAY  
ESPECIALLY SOUTH OF I-72 WHERE HEAT ADVISORY HAS BEEN EXTENDED.  
HIGHS FRIDAY 85-90F OVER CENTRAL IL AND LOWER 90S SOUTH OF I-72.  
DEWPOINTS STILL 75-80F ON FRIDAY TO GIVE THE HIGHER HEAT INDICES  
AGAIN.  
 
MORE CONVECTION IS POSSIBLE SATURDAY ESPECIALLY NORTHERN CWA AND  
LOCALLY HEAVY RAIN REMAINS A RISK. SPC DAY3 OUTLOOK HAS MARGINAL  
RISK OF SEVERE STORMS NORTH OF I-72 ON SATURDAY FOR DAMAGING WINDS  
A RISK. HIGH HEAT AND HUMIDITY TO BUILD BACK INTO CENTRAL IL  
DURING THIS WEEKEND AND CONTINUE THROUGH AT LEAST TUESDAY  
AFTERNOON WITH HEAT HEADLINES LIKELY NEEDED DURING THIS TIME  
PERIOD. HEAT INDICES SAT AFTERNOON 100-105 AND 105-110 SUNDAY  
AFTERNOON. HEAT INDICES 105-115 MONDAY AFTERNOON AND 105-110 TUE  
AFTERNOON LIKELY. COLD FRONT MOVING SOUTHWARD OVER CENTRAL IL TUE  
NIGHT AND INTO SOUTHEAST IL WED TO BRING A CHANCE OF CONVECTION  
AND STARTING COOLING US OFF WITH HIGHS IN LOWER 80S THU WITH SOME  
UPPER 70S POSSIBLE NORTH OF PEORIA.  
 
07  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)  
ISSUED AT 604 PM CDT THU JUL 24 2025  
 
A FRONTAL BOUNDARY HAS STALLED ACROSS CENTRAL ILLINOIS AND WILL  
SERVE AS THE FOCUS FOR MULTIPLE POTENTIAL ROUNDS OF SHOWERS AND  
STORMS THROUGH THE PERIOD. IT'S VERY DIFFICULT AT THIS POINT TO  
PIN DOWN SPECIFIC TIMING AND HAVE TRENDED THE TIMING OF THE PROB30  
GROUPS TOWARDS THE LATEST HRRR...BUT CONFIDENCE IS LOW AND  
ADJUSTMENTS WILL LIKELY BE NEEDED AS THE PICTURE BECOMES MORE  
CLEAR. OUTSIDE OF THE INFLUENCE OF STORMS, ANTICIPATE VFR  
CONDITIONS TO PREVAIL.  
 
DEUBELBEISS  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
HEAT ADVISORY UNTIL 7 PM CDT FRIDAY FOR ILZ052-054>057-061>063-  
066>068-071>073.  
 

 
 

 
 
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