543  
FXUS63 KILX 080857  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
357 AM CDT TUE JUL 8 2025  
   
KEY MESSAGES
 
 
- THERE WILL BE DAILY CHANCES (20-50% COVERAGE) FOR ISOLATED TO  
SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE  
WEEK, MAINLY DURING THE AFTERNOON AND EVENING HOURS. THERE IS A  
MARGINAL RISK (LEVEL 1 OF 5) FOR SEVERE STORMS THIS AFTERNOON  
INTO MID EVENING ACROSS MUCH OF CENTRAL ILLINOIS, SOUTH OF  
HIGHWAY 24.  
 
- SEASONABLE JULY HEAT AND HUMIDITY WILL PREVAIL THROUGH THIS  
WEEKEND, WITH AFTERNOON HIGHS GENERALLY IN THE MID 80S TO NEAR  
90, AND AFTERNOON HEAT INDICES PEAKING IN THE LOWER 90S THIS  
WEEK, EXCEPT 95 TO 100 ON FRIDAY AFTERNOON.  
 

 
   
DISCUSSION
 
 
ISSUED AT 350 AM CDT TUE JUL 8 2025  
 
PREDAWN SURFACE MAP SHOWS WEAK 1018-1019 MB HIGH PRESSURE OVER  
LAKE MI AND EASTERN IL AND WESTERN INDIANA. A WARM FRONT WAS NEAR  
THE IL/MO BORDER AND MO/IA BORDER EXTENDING WESTWARD TO 1012 MB  
LOW ALONG THE WESTERN NE/KS BORDER. AN MCS WAS OVER NW MO, SOUTH  
CENTRAL AND SW IOWA AND INTO SOUTHEAST NEBRASKA AND NORTHEAST KS  
AND TRACKING SOUTHEAST AND KC METRO AND TOWARD KIRKSVILLE MO. A  
FEW ISOLATED SHOWERS WERE OVER NORTHERN IL NORTH OF I-80 PAST FEW  
HOURS, WHILE QUIET WX PREVAILED OVER CENTRAL/SE IL WITH CLEAR TO  
MOSTLY CLEAR SKIES. PATCHY FOG HAD DEVELOPED OVER THE WABASH RIVER  
VALLEY WITH TERRE HAUTE IN VSBY AT 1.5 MILES.  
 
MCS TO WEAK NEXT FEW HOURS AS IT TRACKS SE OVER CENTRAL MO BUT IT  
WILL LAY OUT OUTFLOW BOUNDARIES THAT WILL PUSH EASTWARD INTO WEST  
CENTRAL IL LATER THIS MORNING AND INTO CENTRAL IL DURING THIS  
AFTERNOON. ALSO HAVE A WEAK UPPER LEVEL TROF SHIFTING EASTWARD  
INTO IL BY LATE TODAY AND EVENING. LIKELY WILL SEE REDEVELOPMENT  
OF SCATTERED THUNDERSTORMS NEAR THIS EASTWARD MOVING BOUNDARY WITH  
DAYTIME HEATING AND INSTABILITY INCREASING. THOUGH CONVECTION WILL  
BE MORE ISOLATED IN SOUTHEAST IL THIS AFTERNOON/EVENING. HREF  
MLCAPES ELEVATE TO 1500-2000 J/KG THIS AFTERNOON SW OF I-74 WITH  
WEAK BULK SHEAR VALUES OF 15-20 KTS. SPC DAY1 OUTLOOK HAS EXPANDED  
MARGINAL RISK OF SEVERE STORMS FOR DAMAGING WINDS FURTHER NE INTO  
CENTRAL IL AND NOW COVERS AREAS SOUTH OF HIGHWAY 24 (SOUTH OF  
PEORIA) THIS AFTERNOON INTO MID EVENING. PW VALUES INCREASING TO  
1.75-2.2 INCHES NORTH OF I-70 DURING THIS AFTERNOON AND WILL  
CONTRIBUTE TO LOCALIZED HEAVY RAIN THREAT. THE HREF LPMM STILL  
SHOWS POCKETS OF 1.5-3 INCHES OF RAIN NORTH OF I-70, WITH A FEW  
ISOLATED SPOTS OF 3-5 INCHES SIMILAR TO WHAT WE SAW ON SUNDAY  
AFTERNOON/EARLY EVENING. HIGHS IN THE MID TO UPPER 80S TODAY WITH  
DEWPOINTS RISING INTO THE UPPER 60S/LOWER 70S THIS AFTERNOON WITH  
SSW FLOW. HEAT INDICES TO PEAK FROM 90-95F THIS AFTERNOON (COOLEST  
BY GALESBURG).  
 
CONVECTION CHANCES TO WANE LATER THIS EVENING AND OVERNIGHT WITH  
MUGGY LOWS IN THE UPPER 60S TO AROUND 70F (LOWER 70S BY  
LAWRENCEVILLE). THE WEAK UPPER LEVEL TROF MOVES INTO INDIANA  
DURING WED WHERE BEST CHANCES OF CONVECTION WILL BE. WE HAVE  
CHANCE POPS WED AFTERNOON IN EASTERN/SE IL AND SLIGHT CHANCES AS  
FAR WEST AS THE IL RIVER. SPC DAY2 OUTLOOK DOES NOT HAVE A  
MARGINAL RISK OF SEVERE OVER CWA, BUT MAY BE A FEW STRONGER CELLS  
WED AFTERNOON IN EASTERN IL WITH GUSTY WINDS, AND LOCALLY HEAVY  
RAINS NEAR THE INDIANA BORDER. HIGHS WED BACK IN THE MID TO UPPER  
80S WITH AFTERNOON HEAT INDICES AROUND 90F TO LOWER 90S.  
 
CENTRAL IL WILL BE BETWEEN WX SYSTEM WED NIGHT AND THU WITH WEAK  
UPPER LEVEL TROF PUSHING FURTHER EAST OF IL AND NEXT SHORT WAVE  
TROF TRACKING SE FROM THE NORTHERN PLAINS INTO IOWA ON THU WHERE  
BETTER CHANCES OF CONVECTION WILL BE. WE HAVE MAINLY SLIGHT  
CHANCES OF CONVECTION THU AFTERNOON SOUTH OF I-74. HIGHS THU IN  
THE UPPER 80S AND AFTERNOON HEAT INDICES IN THE LOWER 90S.  
 
A STRONGER NORTHERN STREAM SHORT WAVE TROF TO DROP DOWN FROM THE  
NORTHERN PLAINS AND INTO IL LATE FRIDAY AFTERNOON AND FRI NIGHT  
BRINGING A BETTER CHANCE OF MORE ORGANIZED CONVECTION THAT COULD  
BE STRONG TO SEVERE AS AIRMASS IS QUITE UNSTABLE AND WE WILL SEE  
MORE WIND SHEAR WITH THIS WX SYSTEM. HIGHS AROUND 90F ON FRI WITH  
DEWPOINTS IN THE LOW TO MID 70S AND AFTERNOON HEAT INDICES IN THE  
MID 90S TO NEAR 100F (HIGHEST OVER THE IL RIVER VALLEY). STILL  
PRETTY GOOD CHANCES OF CONVECTION ON SATURDAY ESPECIALLY EASTERN  
IL AS FRONTAL BOUNDARY MOVES THROUGH EASTERN/SE IL. HIGHS SAT IN  
THE MID TO UPPER 80S WITH LAWRENCEVILLE NEAR 90F WHERE HEAT  
INDICES IN THE MID 90S IN SOUTHEAST IL SAT AFTERNOON.  
 
CONVECTION CHANCES TO DIMINISH FROM NW TO SE ON SUNDAY AND  
SEASONABLE TEMPERATURES PREVAILING EARLY NEXT WEEK.  
 
07  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)  
ISSUED AT 1208 AM CDT TUE JUL 8 2025  
 
IN THE SHORT TERM, QUIET CONDITIONS EXPECTED ASIDE FROM SOME  
PATCHY LIGHT FOG IN EAST CENTRAL ILLINOIS TOWARD DAYBREAK. MAIN  
CONCERN WILL BE WITH POTENTIAL FOR THUNDERSTORMS IN THE AFTERNOON  
HOURS. MUCH WILL DEPEND ON RESIDUAL BOUNDARIES FROM CONVECTION  
CURRENTLY WEST OF THE MISSISSIPPI RIVER, BUT WILL MAINTAIN THE  
PROB30 MENTIONS AT ALL SITES WITH SOME TIMING REFINEMENTS BASED ON  
THE 00Z MODEL GUIDANCE. OUTSIDE OF THE STORMS WHICH WILL DROP  
VISIBILITY BRIEFLY, VFR CONDITIONS WILL PREVAIL.  
 
GEELHART  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
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