Alert archive / Illinois / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 90, NWS Chicago, IL

August 19, 2009Grundy County, LaSalle County, Livingston County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Aug 19, 2009, 4:01 PM CDT for Grundy County, LaSalle County, Livingston County, Illinois. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 19, 2009, 4:01 PM CDT (21:01 UTC)
Expired: Aug 19, 2009, 4:56 PM CDT
In force: 55 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon

Counties Grundy County, IL, LaSalle County, IL, Livingston County, IL

The radar

The Chicago radar (KLOT), 66 km from the middle of the area, began a volume at 21:03 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 19, 12:49 PM CDT	Tornado Watch	SPC	6 hr

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 19, 3:16 PM CDT, 45 minutes earlier.

Area forecast discussion, Aug 19, 3:16 PM CDT, 45 minutes before

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Hazardous weather outlook, Aug 19, 11:08 AM CDT, 4 hours 53 minutes before

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The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 19, 3:31 PM CDT	Severe Thunderstorm Warning	LOT	Ford, Livingston	74 min
Aug 19, 4:24 PM CDT	Small Craft Advisory	LOT		29 hr
Aug 19, 4:35 PM CDT	Tornado Warning	LOT	Grundy	25 min
Aug 19, 4:37 PM CDT	Severe Thunderstorm Warning	LOT	Ford, Grundy, Iroquois, Kankakee, Kendall, LaSalle and 2 more	53 min
Aug 19, 4:49 PM CDT	Special Marine Warning	LOT		116 min
Aug 19, 5:08 PM CDT	Severe Thunderstorm Warning	LOT	Ford, Iroquois, Livingston	57 min
Aug 19, 5:14 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Kankakee, Will	61 min
Aug 19, 5:19 PM CDT	Tornado Warning	LOT	Ford, Iroquois, Livingston	29 min
Aug 19, 5:40 PM CDT	Areal Flood Advisory	LOT	Cook, DeKalb, DuPage, Grundy, Kane, Kendall and 4 more	5 hr
Aug 19, 5:57 PM CDT	Tornado Warning	LOT	DeKalb, Kane	33 min
Aug 19, 6:11 PM CDT	Tornado Warning	LOT	Iroquois	32 min
Aug 19, 6:25 PM CDT	Special Marine Warning	LOT		65 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2009 Every severe thunderstorm warning in 2009

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.