Alert archive / Colorado / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 373, NWS Denver/Boulder, CO

August 27, 2026Larimer County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 27, 2026, 2:27 PM MDT for Larimer County, Weld County, Colorado. It was in force for 33 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: Aug 27, 2026, 2:27 PM MDT (20:27 UTC)
Expired: Aug 27, 2026, 3:00 PM MDT
In force: 33 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Larimer County, CO, Weld County, CO

The radar

The Cheyenne radar (KCYS), 61 km from the middle of the area, began a volume at 20:27 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 Aug 27, 11:52 AM MDT, 2 hours 35 minutes earlier.

Area forecast discussion, Aug 27, 11:52 AM MDT, 2 hours 35 minutes before

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In the hours before

Local storm report, Aug 27, 8:31 AM MDT, 5 hours 56 minutes before

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Local storm report, Aug 27, 8:57 AM MDT, 5 hours 30 minutes before

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      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
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      <p id="message2">
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Local storm report, Aug 27, 9:00 AM MDT, 5 hours 27 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.
      </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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Local storm report, Aug 27, 9:39 AM MDT, 4 hours 48 minutes before

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<head>
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  <title>Service Notice</title>
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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>
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</body>
</html>

Local storm report, Aug 27, 9:47 AM MDT, 4 hours 40 minutes before

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<head>
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  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
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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>
  <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
Aug 26, 6:01 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Elbert	26 min
Aug 26, 6:08 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	31 min
Aug 26, 6:19 PM MDT	Areal Flood Advisory	BOU	Douglas	3 hr
Aug 26, 6:21 PM MDT	Areal Flood Advisory	BOU	Arapahoe, Elbert	62 min
Aug 26, 6:23 PM MDT	Special Weather Statement	BOU	Denver	37 min
Aug 26, 6:25 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Elbert, Lincoln, Washington	50 min
Aug 26, 6:37 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver, Douglas, Jefferson	38 min
Aug 26, 6:40 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver, Jefferson	2 hr
Aug 26, 6:47 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Elbert	37 min
Aug 26, 7:08 PM MDT	Flash Flood Warning	BOU	Adams, Arapahoe, Elbert	3 hr
Aug 26, 7:08 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln, Washington	32 min
Aug 26, 7:16 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver	119 min
Aug 26, 7:29 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Washington	14 min
Aug 26, 7:35 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Lincoln, Washington	3 hr
Aug 26, 7:47 PM MDT	Special Weather Statement	BOU	Adams, Arapahoe	43 min
Aug 26, 8:29 PM MDT	Special Weather Statement	BOU	Adams	46 min
Aug 27, 2:33 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	27 min
Aug 27, 2:38 PM MDT	Special Weather Statement	BOU	Gilpin	37 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.