Alert archive / Illinois / Tornado Warnings in 2024

Tornado Warning 34, NWS Chicago, IL

August 5, 2024Winnebago County, Illinois

NWS Chicago, IL issued this tornado warning at Aug 5, 2024, 7:44 PM CDT for Winnebago County, Illinois. It was in force for 31 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 5, 2024, 7:44 PM CDT (00:44 UTC)
Expired: Aug 5, 2024, 8:15 PM CDT
In force: 31 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

County Winnebago County, IL

The radar

The Milwaukee radar (KMKX), 86 km from the middle of the area, began a volume at 00:47 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 5, 5:52 PM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.7 hours before the alert went out and 136 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: 449 J/kg
Mixed-layer CIN: -170 J/kg
Mixed-layer LCL: 1780 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 153 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.0

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 Aug 5, 7:04 PM CDT, 40 minutes earlier.

Area forecast discussion, Aug 5, 7:04 PM CDT, 40 minutes before

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Hazardous weather outlook, Aug 5, 4:13 PM CDT, 3 hours 31 minutes before

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In the hours before

Special weather statement, Aug 5, 4:59 PM CDT, 2 hours 45 minutes before

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Local storm report, Aug 5, 5:33 PM CDT, 2 hours 11 minutes before

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Special weather statement, Aug 5, 5:39 PM CDT, 2 hours 5 minutes before

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Local storm report, Aug 5, 5:55 PM CDT, 1 hour 49 minutes before

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Special weather statement, Aug 5, 6:28 PM CDT, 1 hour 16 minutes before

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Special weather statement, Aug 5, 7:12 PM CDT, 32 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 5, 7:12 PM CDT	Special Weather Statement	LOT	Kendall, Will	48 min
Aug 6, 2:35 AM CDT	Special Marine Warning	LOT		3 hr
Aug 6, 2:53 AM CDT	Special Weather Statement	LOT	Boone, McHenry	52 min
Aug 6, 3:20 AM CDT	Severe Thunderstorm Warning	LOT	Kane, McHenry	40 min
Aug 6, 3:36 AM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Lake	39 min
Aug 6, 3:40 AM CDT	Special Marine Warning	LOT		107 min
Aug 6, 4:02 AM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Lake	43 min

Nearby

Tornado Warnings in Illinois, 2024 Every tornado warning in 2024 Tornadoes in 2024

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.