Alert archive / Illinois / River Flood Warnings in 2026

River Flood Warning 49, NWS Chicago, IL

June 25, 2026Cook County, Illinois

NWS Chicago, IL issued this river flood warning at Jun 25, 2026, 3:53 AM CDT for Cook County, Illinois. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued: Jun 25, 2026, 3:53 AM CDT (08:53 UTC)
Expired: Jun 25, 2026, 5:49 PM CDT
In force: 14 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon

County Cook County, IL

The radar

The Chicago radar (KLOT), 49 km from the middle of the area, began a volume at 08:54 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 Thorn Creek at Thornton (THNI2). The gauge peaked at 9.01 ft at Jun 25, 2026, 5:00 AM CDT.

Action stage: 7.5 ft
Minor stage: 9 ft
Moderate stage: 14 ft
Major stage: 15.5 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 05536275, 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 Jun 25, 2:50 AM CDT, 1 hour 3 minutes earlier.

Area forecast discussion, Jun 25, 2:50 AM CDT, 1 hour 3 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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
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  <script src="index.js"></script>
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Hazardous weather outlook, Jun 25, 3:07 AM CDT, 46 minutes before

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<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
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In the hours before

Local storm report, Jun 24, 9:53 PM CDT, 6 hours before

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<html lang="en">
<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 24, 10:11 PM CDT, 5 hours 42 minutes before

<!doctype html>
<html lang="en">
<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 24, 10:14 PM CDT, 5 hours 39 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 24, 10:20 PM CDT, 5 hours 33 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</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.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 24, 7:03 PM CDT	Severe Thunderstorm Warning	LOT	Cook	70 min
Jun 24, 7:19 PM CDT	Severe Thunderstorm Warning	LOT	Grundy, Kendall	56 min
Jun 24, 7:26 PM CDT	Areal Flood Advisory	LOT	Cook, DuPage, Will	3 hr
Jun 24, 7:51 PM CDT	Areal Flood Advisory	LOT	Cook	2 hr
Jun 24, 8:06 PM CDT	Areal Flood Advisory	LOT	Grundy, LaSalle, Livingston	3 hr
Jun 24, 8:08 PM CDT	Severe Thunderstorm Warning	LOT	Livingston	38 min
Jun 24, 8:37 PM CDT	Flash Flood Warning	LOT	Cook	2 hr
Jun 24, 10:43 PM CDT	Areal Flood Warning	LOT	Cook	6 hr
Jun 24, 10:56 PM CDT	River Flood Warning	LOT	Cook	7 hr
Jun 24, 7:53 PM CDT	Severe Thunderstorm Warning	LOT	Lake	67 min
Jun 24, 8:42 PM CDT	Areal Flood Advisory	LOT	Lake, Porter	2 hr
Jun 24, 8:50 PM CDT	Severe Thunderstorm Warning	LOT	Lake, Porter	26 min
Jun 24, 9:15 PM CDT	Flash Flood Warning	LOT	Lake, Porter	88 min

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.