Alert archive / Illinois / Tornado Warnings in 2010

Tornado Warning 34, NWS Chicago, IL

November 22, 2010McHenry County, Illinois

NWS Chicago, IL issued this tornado warning at Nov 22, 2010, 3:30 PM CST for McHenry County, Illinois. It was in force for 15 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: Nov 22, 2010, 3:30 PM CST (21:30 UTC)
Expired: Nov 22, 2010, 3:45 PM CST
In force: 15 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon

County McHenry County, IL

The radar

The Milwaukee radar (KMKX), 72 km from the middle of the area, began a volume at 21:33 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
Nov 22, 11:23 AM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 9.5 hours before the alert went out and 187 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 31 J/kg
Mixed-layer CIN: -191 J/kg
Mixed-layer LCL: 422 m above ground
0-6 km bulk shear: 73 kt
0-1 km storm-relative helicity: 345 m²/s²
0-3 km storm-relative helicity: 366 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this tornado 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 tornado warning went out at Nov 22, 2:46 PM CST, 44 minutes earlier.

Area forecast discussion, Nov 22, 2:46 PM CST, 44 minutes before

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Hazardous weather outlook, Nov 22, 2:59 PM CST, 31 minutes before

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In the hours before

Local storm report, Nov 22, 2:47 PM CST, 43 minutes before

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Local storm report, Nov 22, 3:19 PM CST, 11 minutes before

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Local storm report, Nov 22, 3:22 PM CST, 8 minutes before

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Local storm report, Nov 22, 3:24 PM CST, 6 minutes before

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Local storm report, Nov 22, 3:28 PM CST, 2 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
Nov 21, 6:19 PM CST	Small Craft Advisory	LOT		9 hr
Nov 22, 3:37 AM CST	Gale Watch	LOT		11 hr
Nov 22, 3:37 AM CST	Small Craft Advisory	LOT		36 hr
Nov 22, 6:57 AM CST	Special Weather Statement	LOT	LaSalle	48 min
Nov 22, 7:44 AM CST	Special Weather Statement	LOT	Cook, Grundy, Kankakee, Kendall, Will	61 min
Nov 22, 8:40 AM CST	Special Weather Statement	LOT	Cook, Kankakee, Will	35 min
Nov 22, 2:06 PM CST	Severe Thunderstorm Warning	LOT	LaSalle, Lee	24 min
Nov 22, 2:16 PM CST	Severe Thunderstorm Warning	LOT	Boone, Ogle, Winnebago	44 min
Nov 22, 2:30 PM CST	Severe Thunderstorm Warning	LOT	DeKalb, LaSalle, Lee	30 min
Nov 22, 2:44 PM CST	Gale Warning	LOT		24 hr
Nov 22, 3:01 PM CST	Severe Thunderstorm Warning	LOT	DeKalb, Kane, LaSalle, Lee	29 min
Nov 22, 3:03 PM CST	Tornado Warning	LOT	Boone, McHenry, Winnebago	27 min
Nov 22, 3:15 PM CST	Severe Thunderstorm Warning	LOT	LaSalle	30 min
Nov 22, 3:23 PM CST	Tornado Warning	LOT	DeKalb, Kane	22 min
Nov 22, 3:37 PM CST	Severe Thunderstorm Warning	LOT	DeKalb, DuPage, Grundy, Kane, Kendall, LaSalle and 2 more	38 min
Nov 22, 3:49 PM CST	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kane	26 min
Nov 22, 4:12 PM CST	Severe Thunderstorm Warning	LOT	Cook, DuPage, Grundy, Kane, Kendall, Lake and 2 more	48 min
Nov 22, 4:18 PM CST	Flash Flood Warning	LOT	Cook	6 hr
Nov 22, 4:42 PM CST	Areal Flood Advisory	LOT	DuPage, Kane, Kendall	2 hr
Nov 22, 4:53 PM CST	Special Marine Warning	LOT		37 min
Nov 22, 4:55 PM CST	Special Weather Statement	LOT	Grundy, Livingston	35 min
Nov 22, 5:59 PM CST	Special Weather Statement	LOT	Cook	31 min

Nearby

Tornado Warnings in Illinois, 2010 Every tornado warning in 2010 Tornadoes in 2010

Sources

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