1 thunderstorm wind, as filed by the National Weather Service.
Every event with a place to put it. 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 St. Louis, MO wrote its last area forecast discussion before the first event at May 5, 2:10 PM CST, 1 hour 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 310 PM CDT SAT MAY 5 2001 MDLS IN RSNBLY GOOD AGREEMENT WITH THE OVERALL EVOLUTION OF UA REGIME DURING THE FCST PD. UPR LOW CURRENTLY OVR ERN CO FCST TO WKN AS IT LIFTS ENE INTO THE CNTRL PLAINS AND THEN PHASE WITH THE NRN STREAM UPR TROF SHARPENING THRU THE NRN PLAINS...WITH FAIRLY HI AMPLITUDE LNG WV TROF RESULTING OVER THE NATIONS MIDSECTION BY LATE MON. SENSIBLE WX AND PCPN THREAT FOR THE CWFA DURING THE SHRT RNG PD APPEARS TO BE STGLY MODULATED BY A NUMBER OF SHRTWV TROFS FCST TO ROT ACRS THE RGN. THE INITIAL SHRTWV TROF AND ASSOCD UVV IS RESULTING IN CURRENT SWATH OF SHRA OVR THE ERN 2/3RDS OF MO. HTG TDA IN ADVANCE OF THE MAIN CLD SHIELD HAS ALLOW THE ATMOS TO BCM WKLY UNSTBL FM ERN MO INTO WRN IL AND THIS HAS ALLOWED FOR A FEW TSRA IN ADVANCE OF THE MAIN PCPN SWATH. PRIND ARE THAT THIS AREA OF PCPN WL CONT TO SHIFT ACRS ERN MO/WRN IL THIS EVNG AS THE SHRTWV TROF ROTS ENE. AFT THIS BATCH THE ONLY OTR PCPN THREAT TNGT APPEARS TO BE ANY REMNANTS OF A PLAINS MCS/SQLN PUSHING INTO MID MO LATE. PCPN EVOLUTION NOT TOTALLY CLEAR CUT ON SUN BUT PRESENT BELIEF IS THAT A SWATH OF SHRA AND FEW EMBDD TSRA ORIGINATING TNGT OVR PLAINS WL AGAIN SHIFT EWD ACRS THE CWFA IN ASSOCN WITH THE NEXT SHRTWV TROF ROTG ACRS THE RGN. THE ETA/NGM ARE ESPCLY ROBUST WITH QPF AS COMPARED TO THE AVN. WHILE INDCTNS ARE THIS SWATH OF PCPN WL BE OVER WRN IL BY MID AFT...THE THIRD ROUND OF PCPN WL BE IN THE OFFING OVR WRN MO. THE APCH OF THE NEXT SHRTWV TROF AND ASSOCD CDFNT SHUD LEAD TO CNVCTV DVLPMNT OVR WRN MO DURING THE AFT WHERE AMS FCST TO RCVR IN THE WAKE OF ERLYR PCPN. THIS PCPN SHUD THEN SPREAD EWD ACRS THE CWFA SUNDAY NIGHT IN ADVANCE OF THE CDFNT. ANY MDL DIFS THAT ARE REALLY APPARENT ARE ASSOCD WITH TMG OF THE CDFNT SUN NGT WITH THE AVN A BIT FASTER. ATTM WL LEAN TWDS THE SLOER ETA/NGM AND KP PCPN THREAT ON MON MRNG OVR ERN MO/WRN IL. HV KEPT MON NGT INTO TUE DRY FOR NOW BUT WL HV TO BE WATCHED. LOW LVLS DRY CNSDRBLY BHD THE CDFNT BUT SHRTWV WV ROTG SE THRU ERN MO/IL RGN LATE MON NGT INTO TUE MAY BE ENUF TO GENERATE SOME MID LVL BASED -SHRA/-TSRA. THREAT ATTM HOWEVER LOOKS MAINLY OVR IA AND CNTRL/NRN IL. IN THE EXTDD...AFT INITIAL COOL DOWN BHD THE CDFNT...TMPS WL SLOWLY MODERATE THRU THE WK. TMPS IN THE EXTDD AE A BLEND OF THE OPERATIONAL MRF MOS AND WARMER ENSEMBLE MEMBERS. WITH PATTERN TRANSITIONING DURING THE LATER PART OF THE WK...CONFIDENCE IN THE DETAILS BCMG LOW. .STL...NONE GLASS
ILZ058>060-064-065-069-070-074-079-095-097>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-060100- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 1125 AM CDT SAT MAY 5 2001 THREAT: SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE REGION. WHEN: THIS AFTERNOON AND TONIGHT. SITUATION: DUE TO MARGINAL INSTABILITY AND WIND FIELDS IN THE ATMOSPHERE...SEVERE WEATHER IS NOT EXPECTED THROUGH TONIGHT. GLASS
The St Louis radar (KLSX), 50 km away, was scanning. The volume nearest the first event began at 21:44 UTC.
1 thunderstorm wind. Local standard time, as filed.
A fast moving line of thunderstorms caused some wind damage in the Alton area. Some trees were down blocking a few roads. There was minor damage to a few decks and backyard pools caused by falling tree limbs.
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: 5244773.