1 lightning, as filed by the National Weather Service.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Chicago, IL wrote its last area forecast discussion before the first event at May 10, 2:25 AM CST, 20 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO IL 325 AM CDT THU MAY 10 2001 FIRST ROUND OF THUNDERSTORMS MOVING INTO THE NORTHWEST PORTIONS OF THE FORECAST AREA THIS MORNING. THIS ACTIVITY EXPECTED TO WEAKEN THIS MORNING...AS IT MOVES AWAY FROM THE MOISTURE AND INSTABILITY AXIS WHICH STRETCHES FROM KANSAS INTO WESTERN WISCONSIN. CURRENT IR SATELLITE DOES INDEED SHOW SIGNIFICANT WARMING IN CLOUD TOPS OVER NORTHWEST IL. WILL USE MORNING WORDING IN FORECAST FOR THIS PRECIP...USING RADAR TRENDS UP TO ISSUANCE TIME FOR EXTENT OF COVERAGE. ETA/AVN CONTINUE TO SHOW SOME DIFFERENCES WITH HANDLING OF INDIVIDUAL WAVES RIPPLING THROUGH THE WESTERLIES OVER THE NORTHERN TIER OF THE COUNTRY. ETA/MESO-ETA ALSO SEEM TO CATCH ON TO THE OUTFLOW ASSOCIATED WITH CURRENT CONVECTION OVER WISCONSIN AND NORTHERN ILLINOIS...WITH OUTFLOW BOUNDARY MOVING JUST SOUTH OF THE FORECAST AREA LATER TODAY. ETA/MESO-ETA DEVELOP CONVECTION ALONG THIS FEATURE LATE THIS AFTERNOON...WHILE AVN PRECIP REMAINS NORTHWEST OF THE FORECAST AREA...ALONG ACTUAL COLD FRONT. BEST MOISTURE POOLING AND INSTABILITY FORECAST TO REMAIN OVER SOUTHERN IOWA THROUGH 00Z FRI. ETA FORECAST SOUNDINGS OVER THE FORECAST AREA SHOW IMPRESSIVE INSTABILITY HERE TOO...WITH CAPES IN THE 1500-3000 J/KG RANGE AND LITTLE CAPPING...BUT IT AGAIN APPEARS TO BE OVER FORECASTING SURFACE DEWPOINTS. ACTUAL AVAILABLE ENERGY LIKELY TO BE LESS. STILL...WITH BOUNDARY SOMEWHERE IN THE VICINITY AND WEAK WAVES RIPPLING THROUGH UPPER FLOW WILL CONTINUE CHANCE POPS FOR LATER TODAY. OUTFLOW BOUNDARY LIKELY TO BE SOMEWHERE ALONG SOUTHERN EDGE OF THE FORECAST AREA...SO WILL RAISE POPS A BIT IN SOUTHERN COUNTIES...WHERE CURRENT FORECAST HAS THEM LOWER THAN IN THE NORTH. NEXT SHORT WAVE APPROACHES TONIGHT PUSHING FRONT INTO ILLINOIS AND NORTHWEST INDIANA BY MORNING...AND RIGHT REAR QUADRANT OF 90 KNOT UPPER JET POTENTIALLY PROVIDING SOME ADDITIONAL UPWARD MOTION. THUS LIKELY POPS STILL LOOK GOOD TONIGHT INTO FRIDAY. POTENTIAL FOR LOCALLY HEAVY RAIN OVERNIGHT ESPECIALLY WESTERN COUNTIES...CLOSER TO BETTER MOISTURE FEED. NORTHERN SECTIONS DRY OUT LATE FRIDAY...BUT WILL KEEP CHANCE POP FRIDAY EVENING IN SOUTHEASTERN COUNTIES CLOSER TO DEPARTING FRONT. TEMPS COULD BE TRICKY TODAY...WITH PRECIP AND RESIDUAL CLOUDINESS FROM OVERNIGHT CONVECTION. 06Z ACARS SOUNDING OUT OF RFD SHOWS 850 MB TEMP OF +14 WHICH WOULD SUGGEST LOW TO MID 80S. WILL BLEND FWC/MAV GUIDANCE FOR TODAY...AND CONTINUE TO GO WITH THE WARMER NUMBERS FOR MINS TONIGHT. FWC/MAV CLOSE FRIDAY WITH COOLER AIR COMING IN FROM THE NORTH BEHIND THE FRONT. .CHI...NONE. RATZER
The national radar mosaic for the moment the first event began.
1 lightning. Local standard time, as filed.
Lightning ignited the wooden roof of an historic old home causing one thousand dollars damge. The house was built in 1852.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2001Every state in 2001This day in weather historyWarnings in Illinois, May 2001
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5241266.