Alert archive / Illinois / River Flood Warnings in 2026

River Flood Warning 13, NWS Chicago, IL

April 4, 2026Lake County, Illinois

NWS Chicago, IL issued this river flood warning at Apr 4, 2026, 11:29 AM CDT for Lake County, Illinois. It took effect at Apr 4, 2026, 3:00 PM CDT. It was in force for 8 days.

The area

The counties it named.

The facts

Issued: Apr 4, 2026, 11:29 AM CDT (16:29 UTC)
In effect from: Apr 4, 2026, 3:00 PM CDT
Expired: Apr 12, 2026, 8:35 AM CDT
In force: 8 days
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: Minor

County Lake County, IL

The radar

The Chicago radar (KLOT), 85 km from the middle of the area, began a volume at 16:32 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 river

Written for the forecast point Des Plaines River near Gurnee (GUNI2). The gauge peaked at 8.41 ft at Apr 8, 2026, 5:00 AM CDT.

Action stage: 6.5 ft
Minor stage: 7 ft
Moderate stage: 9 ft
Major stage: 11 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 05528000, one reading an hour, from a day before the product to a day after it ended. Flood stages are today's.

What forecasters said that day

The local office's own words before this river 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 river flood warning went out at Apr 3, 6:33 PM CDT, 16 hours 56 minutes earlier.

Area forecast discussion, Apr 3, 6:33 PM CDT, 16 hours 56 minutes before

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Hazardous weather outlook, Apr 3, 4:37 PM CDT, 18 hours 52 minutes before

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</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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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 3, 8:08 PM CDT	Flash Flood Warning	LOT	Livingston	6 hr
Apr 3, 9:17 PM CDT	River Flood Warning	LOT	Lake	8 days
Apr 3, 9:46 PM CDT	Flash Flood Warning	LOT	Grundy, Kankakee, Livingston, Will	4 hr
Apr 3, 10:07 PM CDT	Small Craft Advisory	LOT		42 hr
Apr 3, 10:12 PM CDT	River Flood Warning	LOT	LaSalle	4 days
Apr 3, 11:24 PM CDT	Areal Flood Advisory	LOT	Cook	3 hr
Apr 4, 1:59 AM CDT	Areal Flood Warning	LOT	Cook, Grundy, Kankakee, LaSalle, Livingston, Will	8 hr
Apr 4, 6:37 AM CDT	River Flood Warning	LOT	Cook	24 hr
Apr 4, 11:29 AM CDT	River Flood Watch	LOT	Cook, Lake	57 hr
Apr 4, 2:30 PM CDT	River Flood Warning	LOT	Boone, Winnebago	23 hr
Apr 3, 9:23 PM CDT	River Flood Warning	LOT	Lake, Newton	11 days
Apr 4, 5:43 AM CDT	River Flood Warning	LOT	Jasper, Porter	9 days

Nearby

River Flood Warnings in Illinois, 2026 Every river flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive; the gauge from the NWS water service and the USGS.