116  
FXUS63 KILX 250819  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
319 AM CDT FRI JUL 25 2025  
   
KEY MESSAGES
 
 
- A LOW PROBABILITY (5-15% CHANCE) OF SEVERE WEATHER EXISTS NORTH  
OF THE I-70 CORRIDOR BOTH TODAY AND SATURDAY.  
 
- A HEAT ADVISORY REMAINS IN EFFECT ALONG AND SOUTH OF A  
TAYLORVILLE TO PARIS LINE TODAY. THE OPPRESSIVE HEAT WILL SPREAD  
BACK NORTHWARD ACROSS ALL OF CENTRAL ILLINOIS SUNDAY THROUGH  
TUESDAY AS HEAT INDEX VALUES ONCE AGAIN REACH 105-115.  
 
- MUCH COOLER WEATHER IS ON TAP FOR THE MIDDLE AND END OF NEXT  
WEEK...WITH A HIGH PROBABILITY (50-70% CHANCE) THAT HIGHS DROP  
BELOW 80 DEGREES BY NEXT THURSDAY.  
 

 
   
DISCUSSION
 
 
ISSUED AT 319 AM CDT FRI JUL 25 2025  
   
..SEVERE WEATHER RISK TODAY AND SATURDAY
 
 
A BAND OF SCATTERED SHOWERS/THUNDER WILL BE ONGOING FROM KANSAS  
CITY NORTHEASTWARD TO SOUTHERN LAKE MICHIGAN AFTER DAYBREAK TODAY.  
THE AREAL COVERAGE OF THE EARLY MORNING CONVECTION WILL STEADILY  
DECREASE TOWARD MIDDAY, FOLLOWED BY JUST A 30-40% CHANCE FOR A  
THUNDERSTORM MAINLY NORTH OF THE I-70 CORRIDOR THIS AFTERNOON. THE  
ATMOSPHERE WILL BECOME MODERATELY TO STRONGLY UNSTABLE WITH  
SBCAPES IN EXCESS OF 2500J;KG: HOWEVER, DEEP-LAYER WIND SHEAR WILL  
REMAIN WEAK. THE 00Z HREF SHOWS A NARROW CORRIDOR ALONG/NORTH OF  
I-72 WHERE THE PROBABILITY OF SBCAPES GREATER THAN 1000J/KG AND  
0-6KM SHEAR MORE THAN 25KT INCREASES TO 30-40%. GIVEN THE SLIGHT  
UPTICK IN WIND SHEAR IN THE VICINITY OF A REMNANT OUTFLOW  
BOUNDARY, THINK A FEW PULSE-TYPE CELLS WILL POSE THE RISK OF  
ISOLATED DAMAGING WIND GUSTS DURING PEAK HEATING.  
 
CONVECTIVE COVERAGE WILL INCREASE LATE TONIGHT INTO SATURDAY  
MORNING AS A WEAK 25-30KT 850MB JET ORIENTED FROM TEXAS INTO  
WEST-CENTRAL ILLINOIS INTERACTS WITH THE BOUNDARY. WHILE SEVERE  
WEATHER IS NOT EXPECTED, POCKETS OF LOCALLY HEAVY RAINFALL WILL BE  
LIKELY. AFTER THE EARLY MORNING CONVECTION WANES, SCATTERED STORMS  
WILL ONCE AGAIN FIRE ALONG/NEAR ANY REMNANT OUTFLOW BOUNDARIES  
SATURDAY AFTERNOON. THANKS TO A SHORT-WAVE TROUGH TRACKING  
THROUGH THE REGION, WIND SHEAR MAY BE SLIGHTLY MORE FAVORABLE FOR  
ORGANIZED CONVECTION...WITH THE HREF SHOWING THE PROBABILITY OF  
SBCAPES GREATER THAN 1000J/KG AND 0-6KM SHEAR MORE THAN 25KT  
INCREASING TO 50-70% ALONG/NORTH OF I-74. AS A RESULT, THINK A FEW  
STORMS WILL ONCE AGAIN POSE A LOW RISK FOR DAMAGING WIND GUSTS  
SATURDAY AFTERNOON.  
 
   
..OPPRESSIVE HEAT RETURNS IN EARNEST
 
 
AS UPPER RIDGING BUILDS, A NEARLY STATIONARY FRONTAL BOUNDARY WILL  
GET NUDGED NORTH OF CENTRAL ILLINOIS SUNDAY THROUGH TUESDAY.  
THANKS TO RISING UPPER HEIGHTS, DECREASING RAIN CHANCES, AND A  
RETURN TO S/SW BOUNDARY LAYER FLOW ACROSS THE BOARD...TEMPERATURES  
WILL CLIMB BACK INTO THE LOWER TO MIDDLE 90S AND HEAT INDEX  
READINGS WILL ONCE AGAIN REACH THE 105-115 DEGREE RANGE. A HEAT  
ADVISORY IS CURRENTLY IN EFFECT FOR LOCATIONS ALONG AND SOUTH OF A  
TAYLORVILLE TO PARIS LINE FOR TODAY. THIS WILL MOST CERTAINLY NEED  
TO BE EXPANDED ACROSS THE ENTIRE KILX CWA BY SUNDAY.  
 
   
..MUCH COOLER WEATHER BY THE MIDDLE OF NEXT WEEK
 
 
AS HAS BEEN NOTED BY THE PAST SEVERAL MODEL RUNS, A PATTERN  
CHANGE WILL TAKE PLACE LATER NEXT WEEK AS ENERGY ROTATING AROUND A  
DEEP UPPER LOW OVER HUDSON BAY SUPPRESSES THE PREVAILING RIDGE  
OVER THE MIDWEST/OHIO RIVER VALLEY. THIS WILL SEND A STRONG COLD  
FRONT THROUGH CENTRAL ILLINOIS ON WEDNESDAY...FOLLOWED BY MUCH  
COOLER AND LESS HUMID CONDITIONS BY THE END OF THE WEEK. THE 00Z  
NBM EVEN SUGGESTS A HIGH PROBABILITY (50-70% CHANCE) THAT HIGH  
TEMPERATURES DROP BELOW 80 DEGREES EVERYWHERE NORTH OF THE I-70  
CORRIDOR BY NEXT THURSDAY.  
 
BARNES  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)  
ISSUED AT 1224 AM CDT FRI JUL 25 2025  
 
A STATIONARY FRONT DRAPED ACROSS THE AREA WILL BRING PERIODS OF  
SHOWERS AND STORMS OVERNIGHT WITH THE BEST CHANCES AT KPIA AND  
KBMI. THE FRONT WILL BRING ADDITIONAL CHANCES FOR STORMS FRIDAY  
AFTERNOON INTO EVENING, THOUGH CONFIDENCE IN TIMING AND PLACEMENT  
IS RATHER LOW. ADDED PROB30 GROUPS AFTER 00Z SATURDAY, THOUGH THIS  
WILL LIKELY NEED TO BE MODIFIED IN FUTURE TAF UPDATES. WINDS WILL  
BE LIGHT AND VARIABLE OVER THE NEXT 24 HOURS.  
 
NMA  
 

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

 
 

 
 
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