Alert archive / Illinois / River Flood Warnings in 2020

River Flood Warning 49, NWS Chicago, IL

April 29, 2020Grundy County, Illinois

NWS Chicago, IL issued this river flood warning at Apr 29, 2020, 9:40 PM CDT for Grundy County, Illinois. It took effect at Apr 30, 2020, 7:36 AM CDT. It was in force for 47 hr.

The area

The counties it named.

The facts

Issued
Apr 29, 2020, 9:40 PM CDT (02:40 UTC)
In effect from
Apr 30, 2020, 7:36 AM CDT
Expired
May 2, 2020, 6:40 AM CDT
In force
47 hr
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Flood severity
Minor

County Grundy County, IL

The radar

The Chicago radar (KLOT), 45 km from the middle of the area, began a volume at 02:43 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 18.45 ft at May 1, 2020, 3:00 AM CDT.

actionminormoderate101504/3005/0105/0205/03
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 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 29, 9:36 PM CDT, 4 minutes earlier.

Area forecast discussion, Apr 29, 9:36 PM CDT, 4 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>
Hazardous weather outlook, Apr 29, 4:13 PM CDT, 5 hours 27 minutes before
Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
413 PM CDT Wed Apr 29 2020

ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-302115-
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-
413 PM CDT Wed Apr 29 2020 /513 PM EDT Wed Apr 29 2020/

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

.DAY ONE...Tonight.

Weather hazards expected...

  Elevated Flooding Risk.
  Elevated Non thunderstorm wind Risk.
  Significant Lakeshore Flood Risk.

DISCUSSION...

Persistent moderate rain will continue through late tonight.
Additional amounts of one to one and a half inches are possible
in an area of northeast Illinois. This may result in impacting
flooding, while elsewhere localized more nuisance flooding may
occur.

Northerly winds will increase into tonight, with gusts of 35 to
40 mph. Higher gusts will be seen along the lake front. Waves
from these strong winds will likely result in lakeshore flooding
along the Cook county and northwest Indiana shorelines.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Thursday...
  Limited Non Thunderstorm Wind Risk.
  Significant Lakeshore Flood Risk.
Sunday...
  Limited Thunderstorm Risk.

DISCUSSION:

Northerly winds will continue to gust 35 to possibly 40 mph over
land on Thursday while 40 to 50 mph gusts may be seen along the
lake front. This will continue high waves and lakeshore flooding.

.SPOTTER INFORMATION STATEMENT...

  Spotter activation will not be necessary through tonight.

LMZ740>745-302115-
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-
413 PM CDT Wed Apr 29 2020

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...

  Gale force winds and or very hazardous waves.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.

Thursday...
  Gale force winds and or very hazardous waves are likely.
Friday...
  Hazardous conditions for small craft are likely.

Petr

Visit us at http://weather.gov/chicago

Follow us on Facebook, Twitter, and Youtube at:
www.facebook.com/nwschicago
www.twitter.com/nwschicago
www.youtube.com/nwschicago

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 8:22 PM CDTWind AdvisoryLOTCook, DuPage, Lake19 hr
Apr 29, 8:28 PM CDTLakeshore Flood AdvisoryLOTLake18 hr
Apr 29, 8:48 PM CDTAreal Flood AdvisoryLOTCook, DuPage, Ford, Grundy, Iroquois, Kane and 7 more7 hr
Apr 29, 8:52 PM CDTRiver Flood WarningLOTCook30 hr
Apr 29, 9:14 PM CDTRiver Flood AdvisoryLOTWill9 hr
Apr 29, 9:23 PM CDTRiver Flood WarningLOTLaSalle52 hr
Apr 29, 9:33 PM CDTRiver Flood AdvisoryLOTKankakee9 hr
Apr 29, 9:33 PM CDTRiver Flood AdvisoryLOTGrundy, Kankakee, Will9 hr
Apr 29, 9:52 PM CDTRiver Flood WarningLOTLaSalle56 hr
Apr 29, 10:21 PM CDTRiver Flood WarningLOTWinnebago11 hr
Apr 29, 10:39 PM CDTRiver Flood WarningLOTCook38 hr
Apr 29, 10:53 PM CDTRiver Flood AdvisoryLOTCook15 hr
Apr 29, 10:55 PM CDTRiver Flood AdvisoryLOTLivingston36 hr
Apr 30, 3:48 AM CDTAreal Flood AdvisoryLOTCook, DuPage, Grundy, Kane, Kankakee, Kendall and 3 more6 hr
Apr 30, 6:30 AM CDTRiver Flood WarningLOTWill34 hr
Apr 30, 6:34 AM CDTRiver Flood WarningLOTKankakee30 hr
Apr 30, 6:34 AM CDTRiver Flood WarningLOTGrundy, Kankakee, Will14 hr
Apr 30, 6:41 AM CDTRiver Flood WarningLOTGrundy20 hr
Apr 30, 6:44 AM CDTRiver Flood WarningLOTDuPage23 hr
Apr 30, 2:31 PM CDTSmall Craft AdvisoryLOT13 hr
Apr 29, 8:48 PM CDTRiver Flood WarningLOTLake31 hr

Nearby

River Flood Warnings in Illinois, 2020Every river flood warning in 2020

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.