Alert archive / South Dakota / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 242, NWS Aberdeen, SD

August 27, 2020Corson County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at Aug 27, 2020, 7:36 PM MDT for Corson County, South Dakota. It was in force for 39 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, 2020, 7:36 PM MDT (01:36 UTC)
Expired
Aug 27, 2020, 8:15 PM MDT
In force
39 min
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Corson County, SD

The radar

The Bismarck radar (KBIS), 123 km from the middle of the area, began a volume at 01:36 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.

IssuedProductOfficeLasted
Aug 27, 5:31 PM MDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 1.6 hours before the alert went out and 124 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, Bismarck Municip, ND at 00:00Z on 2020-08-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 13 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, Bismarck Municip, ND at 00:00Z on 2020-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 193 square meters per square second.19395878Sfc1 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
13 J/kg
Mixed-layer CIN
-290 J/kg
Mixed-layer LCL
1363 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
193 m²/s²
0-3 km storm-relative helicity
166 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

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 Aberdeen, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 27, 5:31 PM MDT, 2 hours 5 minutes earlier.

Area forecast discussion, Aug 27, 5:31 PM MDT, 2 hours 5 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>
Hazardous weather outlook, Aug 27, 3:27 PM MDT, 4 hours 9 minutes before
Hazardous Weather Outlook...UPDATED
National Weather Service Aberdeen SD
427 PM CDT Thu Aug 27 2020

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-282130-
Traverse-Big Stone-Corson-Campbell-McPherson-Brown-Marshall-Roberts-
Walworth-Edmunds-Day-Dewey-Potter-Faulk-Spink-Clark-Codington-Grant-
Hamlin-Deuel-Stanley-Sully-Hughes-Hyde-Hand-Jones-Lyman-Buffalo-
427 PM CDT Thu Aug 27 2020 /327 PM MDT Thu Aug 27 2020/

This Hazardous Weather Outlook is for west central Minnesota,
central South Dakota, north central South Dakota and northeast
South Dakota.

.DAY ONE...Tonight.

Thunderstorms are expected to move quickly across the region this
evening into the early Friday morning. Some severe storms are
expected with damaging winds and large hail. Wind gusts of 70 to 80
mph or higher are possible along with a possible tornado.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

Thunderstorms are expected again Saturday night, Sunday, Sunday
night into Monday morning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Weather spotters are
encouraged to submit reports to the National Weather Service in
Aberdeen. The public can submit reports on our web page, Facebook
page, or our Twitter feed.

Mohr

The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 27, 8:38 PM MDTSevere Thunderstorm WarningABRDewey37 min
Aug 27, 9:00 PM MDTSevere Thunderstorm WarningABRJones, Stanley45 min
Aug 27, 9:54 PM MDTSevere Thunderstorm WarningABRDewey, Jones, Stanley, Sully36 min
Aug 27, 10:12 PM MDTSevere Thunderstorm WarningABRHughes, Hyde, Jones, Lyman, Stanley, Sully48 min
Aug 27, 10:42 PM MDTSevere Thunderstorm WarningABRBuffalo, Hand, Hughes, Hyde, Stanley, Sully78 min
Aug 28, 12:11 AM MDTSevere Thunderstorm WarningABRClark, Codington, Day, Hamlin, Spink49 min
Aug 28, 12:49 AM MDTSevere Thunderstorm WarningABRCodington, Deuel, Hamlin56 min
Aug 28, 1:20 AM MDTTornado WarningABRDeuel13 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 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.