Alert archive / Illinois / River Flood Advisories in 2021

River Flood Advisory 40, NWS Chicago, IL

October 30, 2021Grundy County, LaSalle County, Illinois

NWS Chicago, IL issued this river flood advisory at Oct 30, 2021, 1:50 AM CDT for Grundy County, LaSalle County, Illinois. It was in force for 49 hr.

The area

The counties it named.

The facts

Issued: Oct 30, 2021, 1:50 AM CDT (06:50 UTC)
Expired: Nov 1, 2021, 2:37 AM CDT
In force: 49 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon

Counties Grundy County, IL, LaSalle County, IL

The radar

The Chicago radar (KLOT), 57 km from the middle of the area, began a volume at 06:50 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 Illinois River at Morris (MORI2). The gauge peaked at 14.31 ft at Oct 30, 2021, 11:00 PM CDT.

Action stage: 13 ft
Minor stage: 16 ft
Moderate stage: 18 ft
Major stage: 22 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record for site 05542500, 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 advisory 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 advisory went out at Oct 30, 12:43 AM CDT, 1 hour 7 minutes earlier.

Area forecast discussion, Oct 30, 12:43 AM CDT, 1 hour 7 minutes before

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Hazardous weather outlook, Oct 29, 3:35 PM CDT, 10 hours 15 minutes before

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<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.
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The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 30, 6:23 AM CDT	River Flood Warning	LOT	LaSalle	26 hr
Oct 30, 10:36 AM CDT	River Flood Advisory	LOT	Grundy	10 hr
Oct 30, 11:24 AM CDT	River Flood Advisory	LOT	LaSalle	62 hr
Oct 30, 3:01 PM CDT	Small Craft Advisory	LOT		72 hr

Nearby

River Flood Advisories in Illinois, 2021 Every river flood advisory in 2021

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.