Alert archive / Illinois / Flash Flood Warnings in 2013

Flash Flood Warning 7, NWS Chicago, IL

April 18, 20138 counties in Illinois; Lake County, Porter County, Indiana

NWS Chicago, IL issued this flash flood warning at Apr 18, 2013, 5:58 AM CDT for 8 counties in Illinois; Lake County, Porter County, Indiana. It was in force for 8 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: Apr 18, 2013, 5:58 AM CDT (10:58 UTC)
Expired: Apr 18, 2013, 2:00 PM CDT
In force: 8 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

Counties Cook County, IL, Ford County, IL, Grundy County, IL, Iroquois County, IL, Kankakee County, IL, LaSalle County, IL, Livingston County, IL, Will County, IL, Lake County, IN, Porter County, IN

The radar

The Chicago radar (KLOT), 42 km from the middle of the area, began a volume at 10:58 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 00:00Z, 11.0 hours before the alert went out and 131 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 412 m above ground
0-6 km bulk shear: 68 kt
0-1 km storm-relative helicity: 356 m²/s²
0-3 km storm-relative helicity: 444 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 11.4

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 Apr 18, 4:20 AM CDT, 1 hour 38 minutes earlier.

Area forecast discussion, Apr 18, 4:20 AM CDT, 1 hour 38 minutes before

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Hazardous weather outlook, Apr 18, 5:03 AM CDT, 55 minutes before

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In the hours before

Local storm report, Apr 18, 2:04 AM CDT, 3 hours 54 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
204 AM CDT THU APR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0202 AM     FLOOD            CHICAGO                 41.88N 87.63W
04/18/2013                   COOK               IL   LAW ENFORCEMENT

            FLOODING REPORTED ON THE DAN RYAN EXPRESSWAY INCLUDING
            NEAR 87TH STREET AND FROM 159TH STREET TO INTERSTATE 57.

&&

MDB

Local storm report, Apr 18, 2:48 AM CDT, 3 hours 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
248 AM CDT THU APR 18 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0246 AM     FLOOD            NILES                   42.03N 87.81W
04/18/2013                   COOK               IL   TRAINED SPOTTER

            SPOTTER ESTIMATED 3-5 INCHES OF WATER ACROSS LEHIGH ROAD
            BETWEEN TOUHY AVE. AND HOWARD ST.

&&

MDB

Local storm report, Apr 18, 4:54 AM CDT, 1 hour 4 minutes before

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Local storm report, Apr 18, 5:02 AM CDT, 56 minutes before

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Local storm report, Apr 18, 5:28 AM CDT, 30 minutes before

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Local storm report, Apr 18, 5:29 AM CDT, 29 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
Apr 17, 7:31 PM CDT	Special Weather Statement	LOT	Iroquois	29 min
Apr 17, 7:44 PM CDT	Flash Flood Warning	LOT	Grundy, LaSalle, Livingston	8 hr
Apr 17, 8:29 PM CDT	River Flood Warning	LOT	Boone	3 days
Apr 17, 8:31 PM CDT	River Flood Watch	LOT	DeKalb	8 hr
Apr 17, 9:03 PM CDT	River Flood Warning	LOT	Kankakee	62 hr
Apr 17, 9:03 PM CDT	River Flood Warning	LOT	Grundy, Will	56 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Iroquois	23 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Iroquois, Kankakee	33 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Iroquois	23 hr
Apr 17, 9:15 PM CDT	Small Craft Advisory	LOT		10 hr
Apr 17, 9:20 PM CDT	River Flood Warning	LOT	Will	4 days
Apr 17, 9:20 PM CDT	River Flood Warning	LOT	DuPage	3 days
Apr 17, 9:23 PM CDT	River Flood Warning	LOT	LaSalle	3 days
Apr 17, 9:27 PM CDT	River Flood Watch	LOT	Livingston	23 hr
Apr 17, 10:31 PM CDT	River Flood Warning	LOT	Grundy	7 days
Apr 17, 10:31 PM CDT	River Flood Warning	LOT	Grundy	53 hr
Apr 17, 10:31 PM CDT	River Flood Warning	LOT	Cook	39 hr
Apr 18, 2:15 AM CDT	Areal Flood Warning	LOT	Grundy, Kankakee, LaSalle, Livingston, Will	10 hr
Apr 18, 3:19 AM CDT	Gale Watch	LOT		12 hr
Apr 18, 3:19 AM CDT	Gale Warning	LOT		48 hr
Apr 18, 4:01 AM CDT	Wind Advisory	LOT	Ford, Iroquois, Kankakee, Livingston	5 hr
Apr 18, 4:05 AM CDT	Flash Flood Warning Emergency	LOT	Cook, DeKalb, DuPage, Grundy, Kane, Kendall and 3 more	8 hr
Apr 18, 4:34 AM CDT	Special Marine Warning	LOT		116 min
Apr 18, 4:52 AM CDT	River Flood Warning	LOT	DeKalb	33 hr
Apr 18, 5:45 AM CDT	River Flood Warning	LOT	Cook	46 hr
Apr 18, 6:14 AM CDT	Special Weather Statement	LOT	Cook, DuPage, Grundy, Kankakee, Kendall, LaSalle and 2 more	61 min
Apr 18, 6:45 AM CDT	Special Marine Warning	LOT		2 hr
Apr 18, 7:06 AM CDT	Special Weather Statement	LOT	Cook, DuPage, Kankakee, Will	39 min
Apr 18, 7:09 AM CDT	Special Weather Statement	LOT	Cook, DuPage, Kankakee, Will	36 min
Apr 18, 7:18 AM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kankakee, Will	57 min
Apr 18, 7:24 AM CDT	Special Marine Warning	LOT		2 hr
Apr 18, 8:09 AM CDT	Severe Thunderstorm Warning	LOT	Iroquois, Kankakee	96 min
Apr 18, 12:00 PM CDT	Flash Flood Warning	LOT	Cook, DeKalb, DuPage, Grundy, Kane, Kankakee and 5 more	8 hr
Apr 18, 1:28 PM CDT	Areal Flood Warning	LOT	Boone, DeKalb, Kane, Lake, Lee, McHenry and 2 more	6 hr
Apr 18, 4:52 PM CDT	Small Craft Advisory	LOT		5 hr
Apr 17, 8:05 PM CDT	River Flood Warning	LOT	Lake	65 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Porter	28 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Jasper, Porter	28 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Jasper	27 hr
Apr 17, 9:14 PM CDT	River Flood Watch	LOT	Newton	24 hr

Nearby

Flash Flood Warnings in Illinois, 2013 Flash Flood Warnings in Indiana, 2013 Every flash flood warning in 2013

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.