Alert archive / Illinois / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 64, NWS Chicago, IL

June 21, 20144 counties in Illinois; Lake County, Indiana

NWS Chicago, IL issued this severe thunderstorm warning at Jun 21, 2014, 1:16 PM CDT for 4 counties in Illinois; Lake County, Indiana. It was in force for 44 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: Jun 21, 2014, 1:16 PM CDT (18:16 UTC)
Expired: Jun 21, 2014, 2:00 PM CDT
In force: 44 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Cook County, IL, Grundy County, IL, Kankakee County, IL, Will County, IL, Lake County, IN

The radar

The Chicago radar (KLOT), 26 km from the middle of the area, began a volume at 18:16 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 nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 6.3 hours before the alert went out and 157 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: 47 J/kg
Mixed-layer CIN: -222 J/kg
Mixed-layer LCL: 1469 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 44 m²/s²
0-3 km storm-relative helicity: 34 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

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 Jun 21, 1:00 PM CDT, 16 minutes earlier.

Area forecast discussion, Jun 21, 1:00 PM CDT, 16 minutes before

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Hazardous weather outlook, Jun 21, 11:00 AM CDT, 2 hours 16 minutes before

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In the hours before

Special weather statement, Jun 21, 8:08 AM CDT, 5 hours 8 minutes before

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Special weather statement, Jun 21, 12:39 PM CDT, 37 minutes before

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Local storm report, Jun 21, 1:08 PM CDT, 8 minutes before

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Special weather statement, Jun 21, 1:11 PM CDT, 5 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
Jun 20, 7:22 PM CDT	Dense Fog Advisory	LOT	Lake	14 hr
Jun 20, 9:01 PM CDT	River Flood Advisory	LOT	LaSalle	48 hr
Jun 20, 9:01 PM CDT	River Flood Advisory	LOT	Bureau, LaSalle	58 hr
Jun 21, 12:39 PM CDT	Special Weather Statement	LOT	Kendall	36 min
Jun 21, 1:11 PM CDT	Special Weather Statement	LOT	Will	34 min
Jun 21, 2:42 PM CDT	Severe Thunderstorm Warning	LOT	Grundy, Iroquois, Kankakee, Livingston, Will	48 min
Jun 21, 3:28 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois, Kankakee, Livingston	62 min
Jun 21, 3:35 PM CDT	Special Weather Statement	LOT	Winnebago	40 min
Jun 21, 3:41 PM CDT	Areal Flood Advisory	LOT	Grundy, Iroquois, Kankakee, LaSalle, Livingston	6 hr
Jun 21, 4:01 PM CDT	Special Weather Statement	LOT	Lee	44 min
Jun 21, 4:09 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois	49 min
Jun 21, 4:17 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Lake, McHenry	58 min
Jun 21, 4:23 PM CDT	Tornado Warning	LOT	Lake, McHenry	34 min
Jun 21, 4:40 PM CDT	Severe Thunderstorm Warning	LOT	LaSalle, Lee	52 min
Jun 21, 4:41 PM CDT	Special Marine Warning	LOT		2 hr
Jun 21, 4:46 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois	47 min
Jun 21, 4:51 PM CDT	Tornado Warning	LOT	Iroquois	39 min
Jun 21, 5:07 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kane, Lake	53 min
Jun 21, 5:11 PM CDT	Areal Flood Advisory	LOT	Cook, DeKalb, DuPage, Kane, Lake, Lee and 2 more	6 hr
Jun 21, 5:36 PM CDT	Flash Flood Warning	LOT	Cook, DuPage	6 hr
Jun 21, 5:37 PM CDT	Special Marine Warning	LOT		83 min
Jun 21, 5:42 PM CDT	Areal Flood Advisory	LOT	Iroquois	6 hr
Jun 21, 5:44 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Grundy, Kane, Kendall, Will	61 min
Jun 21, 5:56 PM CDT	Areal Flood Advisory	LOT	DeKalb, Grundy, Kane, Kendall, Will	6 hr
Jun 21, 6:32 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Kankakee, Will	58 min
Jun 21, 6:36 PM CDT	Flash Flood Warning	LOT	Lake	6 hr

Nearby

Severe Thunderstorm Warnings in Illinois, 2014 Severe Thunderstorm Warnings in Indiana, 2014 Every severe thunderstorm warning in 2014

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.