Alert archive / Illinois / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 5, NWS Chicago, IL

April 9, 2015Cook County, Will County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Apr 9, 2015, 12:17 AM CDT for Cook County, Will County, Illinois. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 9, 2015, 12:17 AM CDT (05:17 UTC)
Expired: Apr 9, 2015, 1:00 AM CDT
In force: 43 min
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Cook County, IL, Will County, IL

The radar

The Chicago radar (KLOT), 24 km from the middle of the area, began a volume at 05:20 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.

What forecasters said that day

The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Apr 8, 5:53 PM CDT, 6 hours 24 minutes earlier.

Area forecast discussion, Apr 8, 5:53 PM CDT, 6 hours 24 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 8, 4:28 PM CDT, 7 hours 49 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
Apr 8, 10:11 PM CDT	Marine Dense Fog Advisory	LOT		17 hr
Apr 8, 11:13 PM CDT	Severe Thunderstorm Warning	LOT	Grundy, Will	47 min
Apr 8, 11:13 PM CDT	Severe Thunderstorm Warning	LOT	DeKalb	47 min
Apr 8, 11:35 PM CDT	Severe Thunderstorm Warning	LOT	Boone, DeKalb, Kane, McHenry	40 min
Apr 9, 12:05 AM CDT	Special Weather Statement	LOT	Will	25 min
Apr 9, 12:27 AM CDT	Severe Thunderstorm Warning	LOT	Kane, McHenry	23 min
Apr 9, 12:40 AM CDT	Severe Thunderstorm Warning	LOT	Cook	24 min
Apr 9, 3:36 AM CDT	Gale Watch	LOT		6 hr
Apr 9, 9:22 AM CDT	Gale Warning	LOT		34 hr
Apr 9, 10:22 AM CDT	Areal Flood Advisory	LOT	Cook, DuPage, Kane, Lake	3 hr
Apr 9, 3:11 PM CDT	Special Marine Warning	LOT		49 min
Apr 9, 3:15 PM CDT	River Flood Warning	LOT	Cook	42 hr
Apr 9, 3:15 PM CDT	River Flood Warning	LOT	Cook	52 hr
Apr 9, 3:23 PM CDT	River Flood Advisory	LOT	Lake	4 days
Apr 9, 3:23 PM CDT	River Flood Advisory	LOT	Will	70 hr
Apr 9, 3:31 PM CDT	River Flood Advisory	LOT	Cook	36 hr
Apr 9, 5:27 PM CDT	Severe Thunderstorm Warning	LOT	Boone, Winnebago	18 min
Apr 9, 6:09 PM CDT	Tornado Warning	LOT	Boone, DeKalb, Ogle, Winnebago	36 min
Apr 9, 6:11 PM CDT	Severe Thunderstorm Warning	LOT	Lee, Ogle	34 min
Apr 9, 6:27 PM CDT	Severe Thunderstorm Warning	LOT	Ogle	33 min
Apr 9, 6:35 PM CDT	Tornado Warning	LOT	Lee, Ogle	25 min
Apr 9, 6:37 PM CDT	Tornado Warning	LOT	Boone, Winnebago	23 min
Apr 9, 6:49 PM CDT	Severe Thunderstorm Warning	LOT	Ogle, Winnebago	26 min
Apr 9, 6:56 PM CDT	Tornado Warning	LOT	Boone, McHenry	34 min
Apr 9, 6:58 PM CDT	Tornado Warning Tornado observedConsiderable damage threat	LOT	Boone, DeKalb, Ogle, Winnebago	47 min
Apr 9, 12:12 AM CDT	Special Weather Statement	LOT	Porter	33 min
Apr 9, 5:27 AM CDT	Special Weather Statement	LOT	Benton	48 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2015 Every severe thunderstorm warning in 2015

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.