409  
FXUS63 KILX 051606  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
1106 AM CDT TUE MAY 5 2026  
   
KEY MESSAGES
 
 
- WAVES OF SHOWERS WILL CONTINUE TODAY, WITH A FEW  
THUNDERSTORMS ALONG AND SOUTH OF ROUGHLY I-70 WHERE THERE IS A  
LOW (5-14%) RISK FOR FLOODING.  
 
- SHOWERY AND COOL WEATHER WILL CONTINUE THROUGH THE END OF THE  
WORK WEEK, WITH THE NEXT CHANCE (40-50%) FOR STORMS ARRIVING  
SATURDAY NIGHT INTO SUNDAY. THE SEVERE WEATHER RISK APPEARS  
LOW AT THIS TIME.  
 

 
   
UPDATE
 
 
ISSUED AT 1055 AM CDT TUE MAY 5 2026  
 
UPDATED THE FORECAST TODAY AND EVENING TO ADJUST CHANCES OF  
SHOWERS, WITH ONE BATCH OF SHOWERS EXITING EAST OF I-57 LATE  
THIS MORNING AND ANOTHER BATCH OF SHOWERS SPREADING INTO WEST  
CENTRAL IL FROM CENTRAL/NORTHERN MO. THE 2ND BATCH OF SHOWERS TO  
SPREAD ENE ACROSS CENTRAL AND SOUTHEAST PARTS OF CWA (MAINLY SE  
OF THE IL RIVER) NEXT FEW HOURS AND HRRR AND OTHER CAM MEMBERS  
FAIRLY CONSISTENT IN SHOWING THIS. HAVE ISOLATED THUNDERSTORMS  
IN SOUTHEAST IL WITH ADDITIONAL HALF TO 1 INCH OF RAIN EXPECTED.  
SPC DAY1 OUTLOOK HAS MARGINAL RISK SOUTH OF CWA INTO SOUTHERN  
REACHES OF WABASH AND EDWARDS COUNTIES FOR 5% RISK OF DAMAGING  
WINDS. SHOWERS TO DIMINISH DURING MID/LATE EVENING. COLD FRONT  
WAS IN FAR SOUTHEAST LAWRENCE COUNTY, JUST PASSING THROUGH  
LAWRENCEVILLE AND WILL PUSH SOUTHEAST TOWARD THE OHIO RIVER  
EARLY THIS EVENING. ALSO LOWERED HIGH TEMPERATURES A FEW  
DEGREES OVER CENTRAL PORTIONS OF CWA WITH A FAIR AMOUNT OF LOW  
CLOUDS AND NORTH TO NE WINDS. HIGHS MOSTLY IN THE MID TO UPPER  
50S WITH LOWER 60S IN FAR SOUTHEAST IL, A MUCH COOLER DAY THAN  
YESTERDAYS HIGHS IN MID 70S TO LOWER 80S.  
 

 
   
DISCUSSION
 
 
ISSUED AT 1241 AM CDT TUE MAY 5 2026  
 
***** STORMS EARLY THIS MORNING, RAIN TODAY *****  
 
AT 1230AM, SCATTERED THUNDERSTORMS, SOME APPROACHING SEVERE LIMITS,  
WERE ONGOING ACROSS PORTIONS OF CENTRAL ILLINOIS. GIVEN MUCH OF THIS  
ACTIVITY IS BEHIND AN OUTFLOW BOUNDARY SENT OUT OF EVENING STORMS,  
THE WIND RISK SHOULD BE LOW, THOUGH WITH SOME OF THE TALLER CORES  
CAN'T FULLY RULE OUT A MICROBURST OR TWO VIA PRECIPITATION LOADING.  
WE HAVE RECEIVED SEVERAL REPORTS OF HAIL UP TO 1 INCH IN DIAMETER  
RECENTLY, WHICH IS NOT SURPRISING GIVEN 500-1500 J/KG MLCAPE AND 30-  
35 KT EFFECTIVE BULK WIND SHEAR APPARENT IN THE RAP'S MESOANALYSIS.  
DUE TO A 40-50 KT LLJ, STRONGLY VEERING LOW LEVEL WINDS SHOULD  
SUSTAIN STORMS FOR AT LEAST A FEW MORE HOURS, WITH NEARLY 600  
M^2/S^2 0-1KM SRH EVIDENT ON BOTH VWX AND IND'S VAD PROFILERS. MOST  
CONVECTIVE ALLOWING MODELS (CAMS) AND WARN ON FORECAST SYSTEM (WOFS)  
MEMBERS SUGGEST ACTIVITY WILL ABATE WITH WANING INSTABILITY AFTER 2-  
3AM OR SO, BUT A WEAK DISTURBANCE RIDING ALONG THE FRONT WILL SPARK  
ADDITIONAL RAIN AREA-WIDE AND PERHAPS A FEW THUNDERSTORMS IN  
SOUTHEAST ILLINOIS NEAR DAYBREAK. SHOWERS ARE FORECAST TO CONTINUE  
FOR MOST OF THE AREA (THOUGH MAINLY NEAR/SOUTH OF I-72) MUCH OF THE  
DAY, WITH THE MOST PERSISTENT ACTIVITY NEAR AND SOUTH OF ROUGHLY I-  
72/DANVILLE. GIVEN HEAVY RAINFALL (1.25"+ IN AN HOUR) WITH THE  
STORMS EARLY THIS MORNING, AND THE HEAVY RAIN PORTIONS OF CENTRAL  
AND SOUTHEAST ILLINOIS RECEIVED LAST WEEK, THE THRESHOLD FOR  
FLOODING WILL BE LOWER THAN NORMAL. WITH HREF/NBM SHOWING A 10-30%  
CHANCE FOR MORE THAN 2 INCHES OF RAINFALL IN SOUTHEAST ILLINOIS,  
WE'LL NEED TO KEEP ONE EYE ON THIS AREA FOR FLOODING, THOUGH WE  
SUSPECT THE CHANCE IS LOW GIVEN AT LEAST HALF OF THAT 2 INCHES  
SHOULD BE SPREAD OUT OVER 12+ HOURS MID MORNING THROUGH LATE  
EVENING. WITH CLOUD COVER, SHOWERS, AND LOW LEVEL NORTHERLY FLOW  
BEHIND THE COLD FRONT, IT'LL BE A COOL AND GLOOMY DAY WITH HIGHS IN  
THE MID TO UPPER 50S SOUTH OF ROUGHLY I-72/DANVILLE WHERE THE RAIN  
WILL BE MOST PERSISTENT. FURTHER NORTH, TEMPERATURES MAY TOP OUT IN  
THE LOW-MID 60S WITH ANY BREAKS OF SUNSHINE, ESPECIALLY NORTH OF A  
MACOMB TO BLOOMINGTON LINE.  
 
***** STAYING COOL WITH LOW PRECIP CHANCES LATE WEEK *****  
 
ANOTHER SHORTWAVE WILL BRING A 20-30% CHANCE FOR LIGHT RAIN TOMORROW  
MORNING INTO EARLY AFTERNOON, THOUGH RAIN AMOUNTS WILL BE MUCH  
LIGHTER WITH NBM GIVING ONLY A 10-25% CHANCE FOR A WETTING RAIN  
(0.10" OR MORE). WITH A COOL AIRMASS ALOFT (850MB TEMPERATURES  
NEAR/BELOW 0 DEGC), HIGH TEMPERATURES WILL LIKELY (50-70% CHANCE)  
FALL SHY OF 60 DEGF AREA-WIDE TOMORROW AFTERNOON. THIS TREND FOR  
COOL AND SHOWERY WEATHER WILL CONTINUE INTO THE FIRST PART OF THE  
WEEKEND AS THE PARENT UPPER LEVEL TROUGH LINGERS OVER ONTARIO/QUEBEC  
TO FOSTER CONTINUED NORTHWEST FLOW ACROSS THE MIDWEST. THE  
DETERMINISTIC GFS AND ECMWF SUGGEST WE MAY GET A WEAK PUSH OF WARM  
ADVECTION AHEAD OF A SHORTWAVE TROUGH TO WARM THE AREA INTO THE 70S  
SATURDAY AND PROVIDE SOME INSTABILITY FOR SHOWERS/STORMS SATURDAY  
NIGHT INTO EARLY SUNDAY (40-60% CHANCE). OTHERWISE, CONDITIONS  
LOOK MOSTLY DRY NEXT WEEK, WITH A WARMING TREND APPARENT IN  
GLOBAL AND ENSEMBLE DATA; BY WEDNESDAY, THERE IS A 40-60% CHANCE  
FOR HIGH TEMPERATURES WARMER THAN 80 DEGREES FROM NBM.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/
 
 
ISSUED AT 635 AM CDT TUE MAY 5 2026  
 
ALL SITES WILL START AS VFR WITH MID CLOUDS AND LIGHT SHOWERS.  
BMI, SPI, DEC, AND CMI WILL SEE CONTINUOUS SHOWERS THROUGH THE  
DAY AND INTO TONIGHT, BUT CIGS WILL DECREASE LATER THIS  
AFTERNOON AND AGAIN TONIGHT. DEC AND CMI WILL SEE MVFR CIGS  
AFTERNOON AND EVENING SINCE THE FRONT WILL BE CLOSER TO THEM.  
SPI MIGHT, BUT ONLY DROPPING THEM TO 3.5KFT. BMI WILL REMAIN VFR  
AND PIA SHOULD SEE AN END TO THE PRECIP IN THE AFTERNOON. WINDS  
WILL BE NORTH TO NORTHWESTERLY BUT THEN BECOME MORE NORTH-  
NORTHEASTERLY DURING THE DAY AND THEN NORTHEAST FOR THE EVENING.  
SPEEDS WILL BE AROUND 10KTS THROUGH THE PERIOD AS THE FRONT WILL  
BE SLOW TO SINK SOUTH.  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
KEY MESSAGES...BUMGARDNER  
UPDATE...07  
DISCUSSION...BUMGARDNER  
AVIATION...AUTEN  
 
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