Alert archive / Colorado / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 169, NWS Denver/Boulder, CO

July 20, 2009Douglas County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 20, 2009, 11:24 PM MDT for Douglas County, Colorado. It was in force for 51 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: Jul 20, 2009, 11:24 PM MDT (05:24 UTC)
Expired: Jul 21, 2009, 12:15 AM MDT
In force: 51 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon

County Douglas County, CO

The radar

The Denver radar (KFTG), 61 km from the middle of the area, began a volume at 05:28 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.

In the hours before

Special weather statement, Jul 20, 9:47 PM MDT, 1 hour 37 minutes before

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Local storm report, Jul 20, 10:56 PM MDT, 28 minutes before

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<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 Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 20, 9:47 PM MDT	Special Weather Statement	BOU	Broomfield	28 min
Jul 20, 9:56 PM MDT	Severe Thunderstorm Warning	BOU	Broomfield, Weld	34 min
Jul 20, 10:04 PM MDT	Severe Thunderstorm Warning	BOU	Larimer, Weld	41 min
Jul 20, 10:06 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Broomfield, Denver, Jefferson	39 min
Jul 20, 10:22 PM MDT	Tornado Warning	BOU	Adams, Arapahoe, Denver, Jefferson	25 min
Jul 20, 10:24 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver, Weld	51 min
Jul 20, 10:31 PM MDT	Severe Thunderstorm Warning	BOU	Weld	44 min
Jul 20, 10:34 PM MDT	Areal Flood Advisory	BOU	Larimer, Weld	86 min
Jul 20, 10:39 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver, Jefferson	81 min
Jul 20, 10:43 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Denver, Douglas, Jefferson	47 min
Jul 20, 10:56 PM MDT	Severe Thunderstorm Warning	BOU	Weld	34 min
Jul 20, 11:18 PM MDT	Areal Flood Advisory	BOU	Arapahoe, Douglas, Elbert	117 min
Jul 20, 11:27 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver	31 min
Jul 20, 11:36 PM MDT	Tornado Warning	BOU	Douglas	24 min
Jul 21, 12:02 AM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver, Weld	88 min
Jul 21, 3:28 PM MDT	Special Weather Statement	BOU	Douglas	47 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2009 Every severe thunderstorm warning in 2009

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.