Alert archive / Illinois / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 8, NWS Chicago, IL

April 9, 2015Boone County, Winnebago County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Apr 9, 2015, 5:27 PM CDT for Boone County, Winnebago County, Illinois. It was in force for 18 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: Apr 9, 2015, 5:27 PM CDT (22:27 UTC)
Expired: Apr 9, 2015, 5:45 PM CDT
In force: 18 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Boone County, IL, Winnebago County, IL

The radar

The Milwaukee radar (KMKX), 80 km from the middle of the area, began a volume at 22:30 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
Apr 9, 1:48 PM CDT	Tornado Watch	SPC	9 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 Apr 8, 5:53 PM CDT, 23 hours 34 minutes earlier.

Area forecast discussion, Apr 8, 5:53 PM CDT, 23 hours 34 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
Apr 8, 10:11 PM CDT	Marine Dense Fog Advisory	LOT		17 hr
Apr 8, 11:13 PM CDT	Severe Thunderstorm Warning	LOT	Grundy, Will	47 min
Apr 8, 11:13 PM CDT	Severe Thunderstorm Warning	LOT	DeKalb	47 min
Apr 8, 11:35 PM CDT	Severe Thunderstorm Warning	LOT	Boone, DeKalb, Kane, McHenry	40 min
Apr 9, 12:05 AM CDT	Special Weather Statement	LOT	Will	25 min
Apr 9, 12:17 AM CDT	Severe Thunderstorm Warning	LOT	Cook, Will	43 min
Apr 9, 12:27 AM CDT	Severe Thunderstorm Warning	LOT	Kane, McHenry	23 min
Apr 9, 12:40 AM CDT	Severe Thunderstorm Warning	LOT	Cook	24 min
Apr 9, 3:36 AM CDT	Gale Watch	LOT		6 hr
Apr 9, 9:22 AM CDT	Gale Warning	LOT		34 hr
Apr 9, 10:22 AM CDT	Areal Flood Advisory	LOT	Cook, DuPage, Kane, Lake	3 hr
Apr 9, 3:11 PM CDT	Special Marine Warning	LOT		49 min
Apr 9, 3:15 PM CDT	River Flood Warning	LOT	Cook	42 hr
Apr 9, 3:15 PM CDT	River Flood Warning	LOT	Cook	52 hr
Apr 9, 3:23 PM CDT	River Flood Advisory	LOT	Lake	4 days
Apr 9, 3:23 PM CDT	River Flood Advisory	LOT	Will	70 hr
Apr 9, 3:31 PM CDT	River Flood Advisory	LOT	Cook	36 hr
Apr 9, 6:09 PM CDT	Tornado Warning	LOT	Boone, DeKalb, Ogle, Winnebago	36 min
Apr 9, 6:11 PM CDT	Severe Thunderstorm Warning	LOT	Lee, Ogle	34 min
Apr 9, 6:27 PM CDT	Severe Thunderstorm Warning	LOT	Ogle	33 min
Apr 9, 6:35 PM CDT	Tornado Warning	LOT	Lee, Ogle	25 min
Apr 9, 6:37 PM CDT	Tornado Warning	LOT	Boone, Winnebago	23 min
Apr 9, 6:49 PM CDT	Severe Thunderstorm Warning	LOT	Ogle, Winnebago	26 min
Apr 9, 6:56 PM CDT	Tornado Warning	LOT	Boone, McHenry	34 min
Apr 9, 6:58 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	LOT	Boone, DeKalb, Ogle, Winnebago	47 min
Apr 9, 12:12 AM CDT	Special Weather Statement	LOT	Porter	33 min
Apr 9, 5:27 AM CDT	Special Weather Statement	LOT	Benton	48 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2015 Every severe thunderstorm warning in 2015

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.