Alert archive / South Dakota / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 10, NWS Aberdeen, SD

April 20, 2007Hand County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at Apr 20, 2007, 8:01 PM CDT for Hand County, South Dakota. 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: Apr 20, 2007, 8:01 PM CDT (01:01 UTC)
Expired: Apr 20, 2007, 8:30 PM CDT
In force: 29 min
Issued by: NWS Aberdeen, SD
Area: Counties, with a storm outline in the text

County Hand County, SD

The radar

The Aberdeen radar (KABR), 111 km from the middle of the area, began a volume at 01:01 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 20, 1:26 PM CDT	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.0 hours before the alert went out and 280 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2720 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 106 m²/s²
0-3 km storm-relative helicity: 243 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.

In the hours before

Local storm report, Apr 20, 7:05 PM CDT, 56 minutes before

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Local storm report, Apr 20, 7:16 PM CDT, 45 minutes before

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Local storm report, Apr 20, 7:29 PM CDT, 32 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 Aberdeen, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 20, 7:17 PM CDT	Severe Thunderstorm Warning	ABR	Faulk	28 min
Apr 20, 7:47 PM CDT	Severe Thunderstorm Warning	ABR	Faulk	28 min
Apr 20, 8:17 PM CDT	Severe Thunderstorm Warning	ABR	Brown, Faulk, Spink	43 min
Apr 20, 8:32 PM CDT	Severe Thunderstorm Warning	ABR	Hand	28 min
Apr 20, 9:02 PM CDT	Severe Thunderstorm Warning	ABR	Brown	28 min
Apr 21, 3:41 AM CDT	Flash Flood Watch	ABR	Brown, Buffalo, Clark, Codington, Day, Deuel and 16 more	24 hr

Nearby

Severe Thunderstorm Warnings in South Dakota, 2007 Every severe thunderstorm warning in 2007

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.