Alert archive / Illinois / Tornado Warnings in 1997
Tornado Warning 12, NWS Chicago, IL
NWS Chicago, IL issued this tornado warning at May 18, 1997, 8:04 PM CDT for Cook County, Illinois. It was in force for 56 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- May 18, 1997, 8:04 PM CDT (01:04 UTC)
- Expired
- May 18, 1997, 9:00 PM CDT
- In force
- 56 min
- Issued by
- NWS Chicago, IL
- Area
- Whole counties
County Cook County, IL
The radar
The Chicago radar (KLOT), 49 km from the middle of the area, began a volume at 01:08 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 18, 8:05 PM CDT | Thunderstorm Wind 52 | Chicago, IL | On the south side of Chicago, roof and tree damage at 6800 S. California, 8700 Kostner, 7900 South Harlem, 6300 S. Cicero and 5600 Kolmar. A wind gust of 60 mph was reported at Calumet City around 815pm. |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 18, 5:30 PM CDT | Tornado Watch | SPC | 6 hr |
The nearest sounding before it
Lincoln, IL (KILX), launched 00:00Z, 1.1 hours before the alert went out and 210 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1314 J/kg
- Mixed-layer CIN
- -31 J/kg
- Mixed-layer LCL
- 1926 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 104 m²/s²
- 0-3 km storm-relative helicity
- 292 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 8.8
The text
As transmitted, in the capitals the NWS used until 2016.
225 WFUS1 KCHI 190103 RRA TORCHI ILC031-063-091-197-190200- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE CHICAGO IL 804 PM CDT SUN MAY 18 1997 THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A TORNADO WARNING EFFECTIVE UNTIL 900 PM CDT FOR PEOPLE IN THE FOLLOWING LOCATIONS... IN NORTHEAST ILLINOIS ...SOUTHERN COOK COUNTY...GRUNDY COUNTY...KANKAKEE COUNTY ...SOUTHERN WILL COUNTY AND THE ADJACENT WATERS OF SOUTHERN LAKE MICHIGAN AT 800 PM CDT A LINE OF SEVERE THUNDERSTORMS ACCOMPANIED BY EXTREMELY HIGH WINDS...AND SMALL TORNADOES OR GUSTNADOES...WAS MOVING SOUTHEAST AT 50 MPH. THE LINE EXTENDED FROM SOUTH OF OHARE AIRPORT TO JOLIET TO MORRIS IN GRUNDY COUNTY. TAKE COVER IMMEDIATELY. ABANDON MOBILE HOMES GO INSIDE A NEARBY STURDY BUILDING AS A LAST RESORT LIE FLAT IN A DITCH AND COVER YOUR HEAD. &
The office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 18, 7:00 PM CDT | Tornado Warning | LOT | Lake, McHenry | 60 min |
| May 18, 7:09 PM CDT | Severe Thunderstorm Warning | LOT | Kane | 66 min |
| May 18, 7:19 PM CDT | Severe Thunderstorm Warning | LOT | LaSalle, Lee | 56 min |
| May 18, 7:30 PM CDT | Tornado Warning | LOT | Kane | 30 min |
| May 18, 7:42 PM CDT | Severe Thunderstorm Warning | LOT | Kendall, LaSalle | 63 min |
| May 18, 7:47 PM CDT | Tornado Warning | LOT | DuPage, Will | 58 min |
| May 18, 8:04 PM CDT | Tornado Warning | LOT | Grundy, Kankakee, Will | 56 min |
| May 18, 8:52 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois, Kankakee | 2 hr |
| May 18, 8:52 PM CDT | Severe Thunderstorm Warning | LOT | Livingston | 2 hr |
| May 18, 9:18 PM CDT | Tornado Warning | LOT | LaSalle | 57 min |
| May 18, 9:54 PM CDT | Severe Thunderstorm Warning | LOT | Grundy, Livingston | 66 min |
| May 18, 10:50 PM CDT | Severe Thunderstorm Warning | LOT | Iroquois, Kankakee | 55 min |
| May 18, 11:12 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois, Livingston | 63 min |
Nearby
Tornado Warnings in Illinois, 1997Every tornado warning in 1997Tornadoes in 1997
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.