Alert archive / Illinois / Flash Flood Warnings in 2020

Flash Flood Warning 15, NWS Chicago, IL

June 27, 2020Ford County, Iroquois County, Kankakee County, Illinois; Jasper County, Newton County, Indiana

NWS Chicago, IL issued this flash flood warning at Jun 27, 2020, 4:29 PM CDT for Ford County, Iroquois County, Kankakee County, Illinois; Jasper County, Newton County, Indiana. It was in force for 3 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: Jun 27, 2020, 4:29 PM CDT (21:29 UTC)
Expired: Jun 27, 2020, 7:30 PM CDT
In force: 3 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

Counties Ford County, IL, Iroquois County, IL, Kankakee County, IL, Jasper County, IN, Newton County, IN

The radar

The Chicago radar (KLOT), 86 km from the middle of the area, began a volume at 21:30 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 nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.5 hours before the alert went out and 113 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: 1084 J/kg
Mixed-layer CIN: -63 J/kg
Mixed-layer LCL: 1078 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 105 m²/s²
0-3 km storm-relative helicity: 106 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.8

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 Jun 27, 3:43 PM CDT, 46 minutes earlier.

Area forecast discussion, Jun 27, 3:43 PM CDT, 46 minutes before

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Hazardous weather outlook, Jun 27, 4:01 PM CDT, 28 minutes before

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In the hours before

Local storm report, Jun 27, 10:38 AM CDT, 5 hours 51 minutes before

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Special weather statement, Jun 27, 2:22 PM CDT, 2 hours 7 minutes before

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Special weather statement, Jun 27, 3:50 PM CDT, 39 minutes before

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Special weather statement, Jun 27, 4:12 PM CDT, 17 minutes before

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Special weather statement, Jun 27, 4:16 PM CDT, 13 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 26, 7:01 PM CDT	Severe Thunderstorm Warning	LOT	DeKalb, Kane, Kendall	44 min
Jun 26, 7:07 PM CDT	Special Marine Warning	LOT		53 min
Jun 26, 7:12 PM CDT	Flash Flood Warning	LOT	Cook, DuPage, Kane	3 hr
Jun 26, 7:26 PM CDT	Special Weather Statement	LOT	DuPage	19 min
Jun 26, 7:41 PM CDT	Special Weather Statement	LOT	Kendall	34 min
Jun 26, 7:49 PM CDT	Special Weather Statement	LOT	Cook	26 min
Jun 26, 7:51 PM CDT	Special Weather Statement	LOT	Will	24 min
Jun 26, 7:52 PM CDT	Areal Flood Advisory	LOT	Cook, DuPage, Kane, Kendall, Will	3 hr
Jun 26, 7:53 PM CDT	Special Marine Warning	LOT		37 min
Jun 26, 7:53 PM CDT	Special Weather Statement	LOT	LaSalle	22 min
Jun 26, 8:04 PM CDT	Special Weather Statement	LOT	Grundy, Will	56 min
Jun 26, 8:22 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Grundy, Kankakee, LaSalle, Livingston, Will	53 min
Jun 26, 8:53 PM CDT	Severe Thunderstorm Warning	LOT	LaSalle, Livingston	40 min
Jun 26, 10:37 PM CDT	Areal Flood Advisory	LOT	Grundy, Iroquois, Kankakee, LaSalle, Livingston, Will	3 hr
Jun 26, 10:51 PM CDT	Special Weather Statement	LOT	Kankakee	39 min
Jun 27, 12:52 AM CDT	Special Weather Statement	LOT	Iroquois	38 min
Jun 27, 3:02 AM CDT	Special Weather Statement	LOT	Iroquois	28 min
Jun 27, 3:41 AM CDT	Special Weather Statement	LOT	Iroquois	34 min
Jun 27, 3:44 AM CDT	Severe Thunderstorm Warning	LOT	Iroquois	28 min
Jun 27, 4:50 AM CDT	Special Weather Statement	LOT	Ford, Iroquois	55 min
Jun 27, 5:37 AM CDT	Areal Flood Advisory	LOT	Iroquois	3 hr
Jun 27, 5:44 AM CDT	Special Weather Statement	LOT	Ford	46 min
Jun 27, 3:32 PM CDT	Flash Flood Warning	LOT	Iroquois	4 hr
Jun 27, 3:50 PM CDT	Special Weather Statement	LOT	LaSalle	25 min
Jun 27, 4:12 PM CDT	Special Weather Statement	LOT	Iroquois	33 min
Jun 27, 4:16 PM CDT	Special Weather Statement	LOT	LaSalle	29 min
Jun 27, 4:34 PM CDT	Severe Thunderstorm Warning	LOT	Iroquois	41 min
Jun 27, 4:45 PM CDT	Special Weather Statement	LOT	Kankakee	30 min
Jun 27, 5:58 PM CDT	Special Weather Statement	LOT	Kankakee	32 min
Jun 27, 6:10 PM CDT	Areal Flood Advisory	LOT	Iroquois	2 hr
Jun 27, 6:48 PM CDT	Special Weather Statement	LOT	Kankakee	27 min
Jun 26, 8:50 PM CDT	Severe Thunderstorm Warning	LOT	Jasper, Lake, Porter	25 min
Jun 26, 10:14 PM CDT	Special Weather Statement	LOT	Jasper, Newton	31 min
Jun 26, 11:17 PM CDT	Special Weather Statement	LOT	Jasper	43 min
Jun 26, 11:46 PM CDT	Special Weather Statement	LOT	Benton	59 min
Jun 27, 12:04 AM CDT	Severe Thunderstorm Warning	LOT	Benton, Jasper, Newton	41 min
Jun 27, 1:24 AM CDT	Special Weather Statement	LOT	Benton	36 min
Jun 27, 1:40 AM CDT	Special Weather Statement	LOT	Porter	35 min
Jun 27, 1:53 PM CDT	Areal Flood Advisory	LOT	Benton, Jasper, Newton	112 min
Jun 27, 2:22 PM CDT	Special Weather Statement	LOT	Benton	38 min

Nearby

Flash Flood Warnings in Illinois, 2020 Flash Flood Warnings in Indiana, 2020 Every flash flood warning in 2020

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.