Alert archive / Colorado / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 172, NWS Denver/Boulder, CO

August 3, 2020Elbert County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 3, 2020, 5:09 PM MDT for Elbert County, Colorado. It was in force for 7 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 3, 2020, 5:09 PM MDT (23:09 UTC)
Expired
Aug 3, 2020, 5:16 PM MDT
In force
7 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.25 in
Wind
60.0 mph

County Elbert County, CO

The radar

The Denver radar (KFTG), 66 km from the middle of the area, began a volume at 23:09 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 nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 11.2 hours before the alert went out and 101 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2020-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 57 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 12:00Z on 2020-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
57 J/kg
Mixed-layer CIN
-477 J/kg
Mixed-layer LCL
1630 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
40 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 3, 3:06 PM MDT, 2 hours 3 minutes earlier.

Area forecast discussion, Aug 3, 3:06 PM MDT, 2 hours 3 minutes before
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Hazardous weather outlook, Aug 3, 10:45 AM MDT, 6 hours 24 minutes before
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In the hours before

Special weather statement, Aug 3, 1:20 PM MDT, 3 hours 49 minutes before
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Special weather statement, Aug 3, 3:10 PM MDT, 1 hour 59 minutes before
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  <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>
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Special weather statement, Aug 3, 3:27 PM MDT, 1 hour 42 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.
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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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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 2, 6:04 PM MDTSevere Thunderstorm WarningBOULincoln41 min
Aug 2, 6:40 PM MDTSpecial Weather StatementBOUCrowley20 min
Aug 2, 6:44 PM MDTSevere Thunderstorm WarningBOULincoln23 min
Aug 2, 7:03 PM MDTSpecial Weather StatementBOUElbert42 min
Aug 2, 7:08 PM MDTSpecial Weather StatementBOUCrowley22 min
Aug 2, 7:48 PM MDTSpecial Weather StatementBOUElbert27 min
Aug 2, 8:00 PM MDTSpecial Weather StatementBOUElbert45 min
Aug 2, 8:21 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln39 min
Aug 2, 8:52 PM MDTSevere Thunderstorm WarningBOULincoln38 min
Aug 2, 9:31 PM MDTSevere Thunderstorm WarningBOULincoln25 min
Aug 3, 1:20 PM MDTSpecial Weather StatementBOUJackson25 min
Aug 3, 2:31 PM MDTSevere Thunderstorm WarningBOULarimer13 min
Aug 3, 3:10 PM MDTSpecial Weather StatementBOUJefferson50 min
Aug 3, 3:27 PM MDTSpecial Weather StatementBOUBoulder48 min
Aug 3, 3:41 PM MDTSevere Thunderstorm WarningBOUDouglas, Jefferson, Park36 min
Aug 3, 5:15 PM MDTSevere Thunderstorm WarningBOUElbert30 min
Aug 3, 5:23 PM MDTSpecial Weather StatementBOUArapahoe52 min
Aug 3, 5:56 PM MDTSpecial Weather StatementBOUElbert34 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2020Every severe thunderstorm 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.