Alert archive / Illinois / Flash Flood Warnings in 2024

Flash Flood Warning 9, NWS Chicago, IL

July 13, 2024Winnebago County, Illinois

NWS Chicago, IL issued this flash flood warning at Jul 13, 2024, 10:59 PM CDT for Winnebago County, Illinois. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 13, 2024, 10:59 PM CDT (03:59 UTC)
Expired: Jul 14, 2024, 3:44 AM CDT
In force: 5 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

County Winnebago County, IL

The radar

The Milwaukee radar (KMKX), 86 km from the middle of the area, began a volume at 04:01 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

Davenport, (KDVN), launched 00:00Z, 4.0 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: 2405 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 1190 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 47 m²/s²
0-3 km storm-relative helicity: 129 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 6.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jul 13, 6:54 PM CDT, 4 hours 5 minutes earlier.

Area forecast discussion, Jul 13, 6:54 PM CDT, 4 hours 5 minutes before

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Hazardous weather outlook, Jul 13, 3:48 PM CDT, 7 hours 11 minutes before

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In the hours before

Local storm report, Jul 13, 7:43 PM CDT, 3 hours 16 minutes before

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Local storm report, Jul 13, 8:01 PM CDT, 2 hours 58 minutes before

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Special weather statement, Jul 13, 9:35 PM CDT, 1 hour 24 minutes before

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Special weather statement, Jul 13, 10:00 PM CDT, 59 minutes before

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Special weather statement, Jul 13, 10:13 PM CDT, 46 minutes before

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Local storm report, Jul 13, 10:29 PM CDT, 30 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
Jul 13, 9:19 PM CDT	Special Marine Warning	LOT		116 min
Jul 13, 9:35 PM CDT	Special Weather Statement	LOT	McHenry	25 min
Jul 13, 10:00 PM CDT	Special Weather Statement	LOT	Lake	30 min
Jul 13, 10:03 PM CDT	Special Marine Warning	LOT		117 min
Jul 13, 10:13 PM CDT	Special Weather Statement	LOT	Boone, McHenry, Winnebago	47 min
Jul 13, 10:23 PM CDT	Severe Thunderstorm Warning	LOT	Winnebago	37 min
Jul 13, 10:49 PM CDT	Areal Flood Advisory	LOT	Boone, DeKalb, Kane, McHenry, Ogle, Winnebago	3 hr
Jul 13, 11:16 PM CDT	Flash Flood Warning	LOT	Boone, DeKalb, McHenry	5 hr
Jul 13, 11:31 PM CDT	Special Marine Warning	LOT		89 min
Jul 13, 11:41 PM CDT	Areal Flood Advisory	LOT	Cook, DeKalb, DuPage, Kane, Lake, McHenry	3 hr
Jul 14, 12:01 AM CDT	Flash Flood Warning	LOT	Ogle, Winnebago	4 hr
Jul 14, 12:31 AM CDT	Areal Flood Advisory	LOT	Cook	3 hr
Jul 14, 12:40 AM CDT	Special Weather Statement	LOT	DeKalb, Ogle	50 min
Jul 14, 1:02 AM CDT	Special Weather Statement	LOT	DeKalb, Kane	58 min
Jul 14, 2:19 AM CDT	Flood Watch	LOT	Boone, Cook, DeKalb, DuPage, Kane, Lake and 4 more	9 hr
Jul 14, 2:45 AM CDT	Areal Flood Advisory	LOT	Cook, DuPage	75 min
Jul 14, 3:44 AM CDT	Areal Flood Warning	LOT	Winnebago	6 hr
Jul 14, 3:46 AM CDT	Areal Flood Warning	LOT	Boone, DeKalb, McHenry	6 hr
Jul 14, 6:12 AM CDT	Special Weather Statement	LOT	Boone, Ogle, Winnebago	48 min
Jul 14, 7:21 AM CDT	Special Weather Statement	LOT	DeKalb	24 min
Jul 14, 7:36 AM CDT	Special Weather Statement	LOT	LaSalle	24 min
Jul 14, 7:55 AM CDT	Special Weather Statement	LOT	Grundy, Kendall	50 min
Jul 14, 8:42 AM CDT	Severe Thunderstorm Warning	LOT	Will	37 min
Jul 14, 8:49 AM CDT	Special Weather Statement	LOT	Kankakee	41 min
Jul 14, 10:46 AM CDT	Areal Flood Advisory	LOT	Boone, McHenry, Winnebago	6 hr
Jul 14, 3:03 PM CDT	Flood Watch	LOT	Boone, Cook, DeKalb, DuPage, Grundy, Kane and 9 more	11 hr
Jul 14, 9:21 AM CDT	Special Weather Statement	LOT	Newton	24 min
Jul 14, 9:37 AM CDT	Severe Thunderstorm Warning	LOT	Jasper, Lake, Newton, Porter	27 min
Jul 14, 9:43 AM CDT	Special Weather Statement	LOT	Jasper	47 min
Jul 14, 12:30 PM CDT	River Flood Watch	LOT	Lake, Newton	18 hr
Jul 14, 12:30 PM CDT	River Flood Watch	LOT	Jasper, Porter	18 hr

Nearby

Flash Flood Warnings in Illinois, 2024 Every flash flood warning 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.