Alert archive / Colorado / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 400, NWS Denver/Boulder, CO

September 19, 20265 counties in Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Sep 19, 2026, 5:55 PM MDT for 5 counties in Colorado. It was in force for 29 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: Sep 19, 2026, 5:55 PM MDT (23:55 UTC)
Expired: Sep 19, 2026, 6:24 PM MDT
In force: 29 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 0.0 in
Wind: 60.0 mph

Counties Adams County, CO, Arapahoe County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO

The radar

The Denver radar (KFTG), 23 km from the middle of the area, began a volume at 23:59 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 Denver/Boulder, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 19, 12:19 PM MDT, 5 hours 36 minutes earlier.

Area forecast discussion, Sep 19, 12:19 PM MDT, 5 hours 36 minutes before

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In the hours before

Local storm report, Sep 19, 2:21 PM MDT, 3 hours 34 minutes before

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<body>
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    <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.
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      <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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Local storm report, Sep 19, 2:47 PM MDT, 3 hours 8 minutes before

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<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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Special weather statement, Sep 19, 2:54 PM MDT, 3 hours 1 minute 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>
  </main>
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</body>
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Special weather statement, Sep 19, 3:56 PM MDT, 1 hour 59 minutes 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, Sep 19, 4:07 PM MDT, 1 hour 48 minutes 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>

Special weather statement, Sep 19, 5:29 PM MDT, 26 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 Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 19, 12:58 PM MDT	Special Weather Statement	BOU	Arapahoe	47 min
Sep 19, 1:23 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Elbert	52 min
Sep 19, 1:41 PM MDT	Areal Flood Advisory	BOU	Elbert	2 hr
Sep 19, 1:46 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	29 min
Sep 19, 2:08 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Elbert	52 min
Sep 19, 2:16 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	44 min
Sep 19, 2:43 PM MDT	Severe Thunderstorm Warning	BOU	Elbert, Lincoln	47 min
Sep 19, 2:54 PM MDT	Special Weather Statement	BOU	Washington	51 min
Sep 19, 3:14 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	46 min
Sep 19, 3:52 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Lincoln	38 min
Sep 19, 3:56 PM MDT	Special Weather Statement	BOU	Larimer	49 min
Sep 19, 5:29 PM MDT	Special Weather Statement	BOU	Weld	46 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2026 Every severe thunderstorm 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.