Alert archive / Illinois / Flash Flood Warnings in 2022

Flash Flood Warning 5, NWS Chicago, IL

July 5, 20226 counties in Illinois

NWS Chicago, IL issued this flash flood warning at Jul 5, 2022, 12:15 AM CDT for 6 counties in 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 5, 2022, 12:15 AM CDT (05:15 UTC)
Expired: Jul 5, 2022, 5:15 AM CDT
In force: 5 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

Counties Boone County, IL, Cook County, IL, DeKalb County, IL, Kane County, IL, Lake County, IL, McHenry County, IL

The radar

The Chicago radar (KLOT), 61 km from the middle of the area, began a volume at 05:16 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

Davenport, (KDVN), launched 00:00Z, 5.3 hours before the alert went out and 188 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: 3635 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 1008 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 306 m²/s²
0-3 km storm-relative helicity: 538 m²/s²
Significant tornado parameter: 6.2
Supercell composite: 38.0

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 4, 7:43 PM CDT, 4 hours 32 minutes earlier.

Area forecast discussion, Jul 4, 7:43 PM CDT, 4 hours 32 minutes before

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Hazardous weather outlook, Jul 4, 4:22 PM CDT, 7 hours 53 minutes before

Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
422 PM CDT Mon Jul 4 2022

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-052130-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
422 PM CDT Mon Jul 4 2022 /522 PM EDT Mon Jul 4 2022/

This Hazardous Weather Outlook is for portions of North Central
Illinois...Northeast Illinois and Northwest Indiana.

.DAY ONE...Tonight.

Weather hazards expected...

  Elevated Thunderstorm Risk...with an associated:
     Limited Tornado risk.
     Limited hail risk...up to 1 inch diameter.
     Limited damaging wind risk...up to 70 mph.
  Elevated Flooding Risk.
  Limited Excessive Heat Risk.

DISCUSSION...

Scattered thunderstorms will continue late this afternoon into
early this evening. These storms will be capable of producing
damaging winds, large hail and heavy rain that may result in
localized flooding.

Additional scattered thunderstorms are possible later this
evening into the early morning hours. These storms may also be
severe and produce heavy rain with localized flooding.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday...
  Limited Severe Thunderstorm Risk.
  Limited Flooding Risk.
  Elevated Excessive Heat Risk.
Wednesday...
  Limited Severe Thunderstorm Risk.
  Elevated Flooding Risk.
  Limited Excessive Heat Risk.
Thursday...
  Elevated Thunderstorm Risk.
  Limited Excessive Heat Risk.
Friday...
  Limited Thunderstorm Risk.

DISCUSSION:

Dangerous heat indices of 105 to 110 degrees are likely Tuesday
afternoon.

Multiple rounds of showers and thunderstorms are possible Tuesday
through Friday. Any one of these bouts of thunderstorms could
result in a risk of severe thunderstorms and the potential for
localized flash flooding.

.SPOTTER INFORMATION STATEMENT...

Spotters will be needed through tonight.

GENERAL STORM MOTION OF THE DAY:

Moving toward the east southeast at 20 to 30 mph.

LMZ740>745-052130-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
422 PM CDT Mon Jul 4 2022

This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.

.DAY ONE...Tonight.

Weather hazards expected...

  Elevated Thunderstorm Risk...with an associated:
     Limited Waterspout Risk.
     Limited hail risk...up to 1 inch diameter.
     Limited thunderstorm wind gust risk...up to 60 knots.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Tuesday and Wednesday...
  Limited Severe Thunderstorm Risk.
Thursday and Friday...
  Limited Thunderstorm Risk.

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In the hours before

Special weather statement, Jul 4, 9:28 PM CDT, 2 hours 47 minutes before

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Special weather statement, Jul 4, 9:57 PM CDT, 2 hours 18 minutes before

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Local storm report, Jul 4, 11:17 PM CDT, 58 minutes before

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Local storm report, Jul 4, 11:46 PM CDT, 29 minutes before

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Local storm report, Jul 4, 11:51 PM CDT, 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
1151 PM CDT MON JUL 4 2022

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

1144 PM     HEAVY RAIN       2 SW ROSCOE             42.39N 89.04W
07/04/2022  M3.01 INCH       WINNEBAGO          IL   PUBLIC

            PRIVATE WEATHER STATION RECORDED NEARLY
            ABOUT 3 INCHES OF RAINFALL IN JUST OVER 1.5
            HOURS.

&&

WSL

Local storm report, Jul 5, 12:08 AM CDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO IL
1208 AM CDT TUE JUL 5 2022

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

1159 PM     HEAVY RAIN       2 SSE UNION             42.20N 88.53W
07/04/2022  M2.50 INCH       MCHENRY            IL   PUBLIC

            PRIVATE WEATHER STATION RECORDED 2.5 INCHES
            OF RAINFALL IN JUST UNDER 30 MINUTES.

&&

WSL

The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 4, 8:32 PM CDT	Severe Thunderstorm Warning	LOT	Boone, McHenry, Winnebago	58 min
Jul 4, 9:28 PM CDT	Special Weather Statement	LOT	Boone, McHenry	92 min
Jul 4, 9:30 PM CDT	Severe Thunderstorm Warning	LOT	Boone, Winnebago	45 min
Jul 4, 9:57 PM CDT	Special Weather Statement	LOT	Winnebago	93 min
Jul 4, 10:05 PM CDT	Severe Thunderstorm Warning	LOT	Boone, McHenry	35 min
Jul 4, 10:15 PM CDT	Special Marine Warning	LOT		75 min
Jul 4, 10:55 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Kane, Lake, McHenry	50 min
Jul 4, 11:04 PM CDT	Severe Thunderstorm Warning	LOT	Boone, Winnebago	56 min
Jul 4, 11:16 PM CDT	Severe Thunderstorm Warning	LOT	Cook, Lake	59 min
Jul 4, 11:21 PM CDT	Special Marine Warning	LOT		3 hr
Jul 4, 11:22 PM CDT	Severe Thunderstorm Warning	LOT	Kane, McHenry	68 min
Jul 4, 11:31 PM CDT	Areal Flood Advisory	LOT	Boone, Cook, DeKalb, Kane, Lake, McHenry and 1 more	6 hr
Jul 4, 11:51 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage	69 min
Jul 4, 11:56 PM CDT	Flash Flood Warning	LOT	Boone, Winnebago	5 hr
Jul 4, 11:58 PM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Kane, Lake	62 min
Jul 5, 12:14 AM CDT	Severe Thunderstorm Warning	LOT	Cook	38 min
Jul 5, 12:21 AM CDT	Flash Flood Warning	LOT	Cook, DuPage	5 hr
Jul 5, 12:36 AM CDT	Severe Thunderstorm Warning	LOT	Cook, DuPage, Will	69 min
Jul 5, 12:51 AM CDT	Special Marine Warning	LOT		84 min
Jul 5, 3:54 AM CDT	Flood Watch	LOT	Boone, Cook, DuPage, Kane, Lake, McHenry and 2 more	23 hr
Jul 5, 11:25 AM CDT	Marine Dense Fog Advisory	LOT		5 hr
Jul 5, 3:51 PM CDT	Special Weather Statement	LOT	McHenry	24 min
Jul 5, 5:29 PM CDT	Special Weather Statement	LOT	McHenry	46 min
Jul 5, 5:37 PM CDT	Severe Thunderstorm Warning	LOT	Winnebago	68 min
Jul 5, 5:53 PM CDT	Severe Thunderstorm Warning	LOT	McHenry	67 min
Jul 5, 5:56 PM CDT	Tornado Warning	LOT	McHenry	16 min
Jul 5, 6:34 PM CDT	Areal Flood Advisory	LOT	McHenry	36 min
Jul 5, 6:43 PM CDT	Severe Thunderstorm Warning	LOT	Boone, McHenry	77 min
Jul 5, 1:12 AM CDT	Special Weather Statement	LOT	Lake	63 min

Nearby

Flash Flood Warnings in Illinois, 2022 Every flash flood warning in 2022

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.