Illinois, 2001

Hail and Damaging Winds in Illinois, August 9, 2001

August 9, 2001 · NWS LOT · 13 events in 12 counties and zones

A line of strong thunderstorms moved southeast from Wisconsin into Northern Illinois during the evening hours of Thursday, August 9th. These thunderstorms mainly blew down trees and power lines at the following locations: Across all of Ogle and McHenry counties; Fox Lake and Wauconda in Lake county; two miles east of Sycamore in DeKalb county; Dundee, Carpentersville, and Aurora in Kane county;…

Where it happened

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.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
1
Injuries
0
Property damage
$40,000
Crop damage
None recorded
Events
13

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.

What happened

The episode as NWS LOT wrote it up.

A line of strong thunderstorms moved southeast from Wisconsin into Northern Illinois during the evening hours of Thursday, August 9th. These thunderstorms mainly blew down trees and power lines at the following locations: Across all of Ogle and McHenry counties; Fox Lake and Wauconda in Lake county; two miles east of Sycamore in DeKalb county; Dundee, Carpentersville, and Aurora in Kane county; Barrington in Cook county; Earlville in LaSalle county; Coal City in Grundy county; and Beecher in Will county. In Bourbonnais in Kankakee county, a 20 foot by 120 foot metal framed storage building was picked up and carried 10 feet. It landed on 9 parked vehicles. The storage building was a total loss and all nine vehicles suffered major damage. A 16 year old boy was struck by lightning at golf course in Capron in Boone county, the boy died two days later on August 11th. Over 50,000 customers lost power during the storms.

What forecasters said that day

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 Aug 9, 1:50 PM CST, 4 hours 10 minutes earlier.

Area forecast discussion, Aug 9, 1:50 PM CST, 4 hours 10 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO IL
250 PM CDT THU AUG 9 2001

MODEL COMPARISONS WITH SFC DATA INDICATE AVN HAS BETTER HANDLE ON
COLD FRONT PLACEMENT WHICH STRETCHES AT 18Z FROM JUST W OF GRB TO
JUST E OF ALO. DEVELOPMENT SO FAR IN IA AND SRN WI HAS BEEN SPARTAN
WITH A FEW SHOWERS FROM MLI ON S THRU BRL. THIS MOVING RATHER SLOWLY
EAST AND PROBABLY WONT REACH CWA TIL 5PM. LOWER DBZ ON 88D INDICATE
THE LINE ASSOCIATED WITH THESE NWRN IL SHWRS APPEARS TO CONTINUE
NEWD THRU RFD TO THE MKE AREA. SAME LIGHT DBZ HIGHLITE THE COLD
FRONT ACROSS WI AND IA.

GOES SOUNDER INDICATES THE MKE AREA HAS SOME DECENT INHIBITION BUT
NOT SO MUCH REST OF NRN IL. ON THE OTHER HAND CAPES ARE BLO 1000 IN
NWRN IL. RICK DIMAIO AT FOX NOTED THE WESTERLY 850 WINDS NOT
SUPPORTIVE OF SEVERE WX WHICH SEEMS TO BE THE CASE ON UPPER AIR PLOT
ACROSS NRN IL. THUS MAY NOT BE RISK OF SEVERE TONIGHT AND MAY EVEN
ISSUE FCST WITH CHC POPS RATHER THAN LIKELY OR CATEGORICAL.

POST FRONTAL COOLING IMMINENT THOUGH LOOKING AT TEMPS AND DWPTS WEST
OF COLD FRONT. THUS WILL KEEP HEAT WARNG GOING WITH THE 330PM
PACKAGE AND HAVE EVENING SHIFT CANCEL IT WITH FROPA. THAT SHOULD PUT
THIS EVENT TO REST WITH WELCOMED COOLER AND DRIER AIR FOR FRIDAY AND
THE WEEKEND. GUIDANCE HAS ALREADY BACKED OFF FROM MID 70S FOR HIGHS
FRIDAY AND SATURDAY ON AVN AT LEAST AND WILL LIKELY GO WITH NEAR 80
OR 75 TO 80 RANGE.

.CHI...EXCESSIVE HEAT WARNING THRU THIS EVENING CHI METRO.

BRUMER

The radar

The Chicago radar (KLOT), 111 km away, was scanning. The volume nearest the first event began at 00:01 UTC.

Open the radar archive at this moment

Event by event

11 thunderstorm wind, 1 lightning, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Ogle

When
August 9, 6:00 PM CST to 6:10 PM CST
Where
Ogle County, Countywide
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
42.050, -89.283

Thunderstorm Wind, McHenry

When
August 9, 6:30 PM CST
Where
McHenry County, Countywide
Measured
55 kt (63 mph)
Reported by
LAW ENFORCEMENT
Coordinates
42.317, -88.433

Thunderstorm Wind, Lake

When
August 9, 6:35 PM CST to 6:45 PM CST
Where
Lake County, Fox Lake
Measured
52 kt (60 mph)
Reported by
LAW ENFORCEMENT
Coordinates
42.400, -88.167

Thunderstorm Wind, De Kalb

When
August 9, 6:35 PM CST
Where
De Kalb County, 2 mi E of Sycamore
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
41.983, -88.650

Lightning, Boone

When
August 9, 6:49 PM CST
Where
Boone County, Capron
Deaths
1 direct, 0 indirect
Reported by
NEWSPAPER
Coordinates
42.323, -88.823 (the zone’s center; the record gives no point)

Thunderstorm Wind, Kane

When
August 9, 6:55 PM CST
Where
Kane County, Dundee
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
42.083, -88.300

Thunderstorm Wind, Cook

When
August 9, 7:10 PM CST
Where
Cook County, Barrington
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
42.150, -88.133

Thunderstorm Wind, Kane

When
August 9, 7:20 PM CST
Where
Kane County, Aurora
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
41.767, -88.317

Hail, Du Page

When
August 9, 7:20 PM CST
Where
Du Page County, Villa Park
Measured
1.75 in hail
Reported by
TRAINED SPOTTER
Coordinates
41.883, -87.983

Thunderstorm Wind, La Salle

When
August 9, 7:50 PM CST
Where
La Salle County, Earlville
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
41.583, -88.933

Thunderstorm Wind, Grundy

When
August 9, 8:05 PM CST
Where
Grundy County, Coal City
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
41.283, -88.283

Thunderstorm Wind, Will

When
August 9, 8:40 PM CST
Where
Will County, Beecher
Measured
50 kt (58 mph)
Reported by
LAW ENFORCEMENT
Coordinates
41.350, -87.633

Thunderstorm Wind, Kankakee

When
August 9, 8:40 PM CST
Where
Kankakee County, Bourbonnais
Measured
60 kt (69 mph)
Property damage
$40,000
Reported by
NWS EMPLOYEE(OFF DUTY)
Coordinates
41.150, -87.883

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

EventDateAgeSexWhereKind
Lightning, Boone2001-08-1116MaleGolfingDirect

What these are

Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Lightning
A lightning strike that killed, injured or caused damage.
Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Illinois in 2001Every state in 2001This day in weather historyWarnings in Illinois, August 2001

Sources

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: 5264195, 5264196, 5264197, 5264198, 5264202, 5264199, 5264200, 5264201, 5264203, 5264204, 5264205, 5264206, 5264207.