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 Sep 7, 1:50 AM CST, 6 hours 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO IL 250 AM CDT FRI SEP 7 2001 SHOWERS AND TSTORMS ABOUT GONE EASTERN AND SOUTHERN CWFA AND EXPECT A DOWNHILL TREND SOON NORTHWEST AS SHORT WAVE NORTHEAST MISSOURI LIFTS ON BY BEFORE DAYBREAK. AT THE SURFACE, A FRONT DRAPED FROM NORTHWEST MINNESOTA TO SOUTHWESTERN KANSAS WITH LOTS OF PRECIP FROM WINDING DOWN TSTORMS. IN THE LARGER PICTURE DEVELOPING TROUGH OVER THE ROCKIES NEXT DAY OR SO TO SEE A SERIES OF STRONGER AND WEAKER SHORT WAVES MOVING THROUGH, MAKING TIMING OF PRECIPITATION THREAT DIFFICULT. AIRMASS OVER AREA TO PERHAPS DRY A LITTLE TODAY AND TONIGHT IN TERMS OF PRECIPITABLE WATER. MODELS DIFFER ON DETAILS WITH NO MAJOR SHORT WAVES CLEARLY AFFECTING AREA TODAY AND TONIGHT BUT SMALL AREAS OF UPLIFT/SUBSIDENCE SEEMINGLY APPEARING AT RANDOM, DRIVEN BY LOWER LEVELS PERHAPS. MINIMAL ACTIVITY EXPECTED AFTER DAYBREAK BUT COULD RESUME FROM COMBINATION OF DIURNAL HEATING AND A WIGGLE IN THE FLOW DURING THE AFTERNOON AND EARLY EVENING. THEN AGAIN A LULL UNTIL SOMETIME SATURDAY MIDDAY OR LATER WHEN STRONG SHORT WAVE APPROACHES FROM THE WEST. HERE MODELS DIFFER AGAIN ON THINGS LIKE FRONTAL TIMING AND AT THIS POINT A BLEND STILL SEEMS BEST, LEADING TO A CONTINUED LIKELIHOOD OF PRECIPITATION. THROUGHOUT NEXT COUPLE DAYS, POPS AND EXPECTED PRECIP AMOUNTS GENERALLY HIGHER WEST. MODELS REALLY DIVERGE BEYOND SATURDAY AS AVN FIRST PUSHES FRONT THROUGH QUICKER THAN ETA, THE BRINGS A WAVE UP TO AFFECT US AS THE MAIN WESTERN TROUGH COMES OUT SUNDAY. ETA SLOWER WITH FRONT AND DRAGS PRECIP THREAT INTO SATURDAY NIGHT WITH FRONT. GOING FORECAST REFLECTS BOTH POSSIBILITIES AND WONT BE CHANGED MUCH AT THIS TIME AS WINNER IS UNCLEAR. AVN/NGM MOS TEMPS NEARLY IDENTICAL NEXT 48 HOURS. THEY COULD BE JUST A BIT LOW TODAY GIVEN LITTLE CHANGE IN FORECAST 850 TEMPS FROM THURSDAY EVENING TO FRIDAY EVENING. .CHI...NONE KAPLAN
The Milwaukee radar (KMKX), 72 km away, was scanning. The volume nearest the first event began at 13:52 UTC.
1 lightning. Local standard time, as filed.
Lightning struck a radio tower knocking out a transmitter which had to be replaced.
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, September 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: 5267520.