Alert archive / South Dakota / Mesoscale Discussions in 2016

Mesoscale Discussion 1525

August 11, 20166 counties in Nebraska; 12 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Aug 11, 2016, 4:56 PM MDT for 6 counties in Nebraska; 12 counties in South Dakota. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: Aug 11, 2016, 4:56 PM MDT (22:56 UTC)
Expired: Aug 11, 2016, 6:30 PM MDT
In force: 94 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Box Butte County, NE, Cherry County, NE, Garden County, NE, Grant County, NE, Morrill County, NE, Sheridan County, NE, Bennett County, SD, Haakon County, SD, Hughes County, SD, Jackson County, SD, Jones County, SD, Mellette County, SD, Oglala Lakota County, SD, Pennington County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Todd County, SD

The radar

The Rapid City radar (KUDX), 134 km from the middle of the area, began a volume at 23:00 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 444Aug 11, 5:30 PM MDT

The nearest sounding before it

Rapid City, SD (KRAP), launched 12:00Z, 10.9 hours before the alert went out and 135 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: 1152 J/kg
Mixed-layer CIN: -108 J/kg
Mixed-layer LCL: 995 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: -92 m²/s²
0-3 km storm-relative helicity: 2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted.

<!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>

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 11, 11:37 AM MDT	Mesoscale Discussion	SPC	Antelope, Boone, Boyd, Burt, Cedar, Cuming and 12 more	2 hr
Aug 11, 1:35 PM MDT	Mesoscale Discussion	SPC	Banner, Box Butte, Cheyenne, Dawes, Garden, Kimball and 4 more	2 hr
Aug 11, 2:26 PM MDT	Mesoscale Discussion	SPC	Antelope, Boone, Burt, Butler, Cass, Cedar and 24 more	2 hr
Aug 11, 2:55 PM MDT	Severe Thunderstorm Watch	SPC	Antelope, Boone, Burt, Butler, Cass, Cedar and 24 more	7 hr
Aug 11, 4:31 PM MDT	Mesoscale Discussion	SPC	Blaine, Brown, Lincoln, Logan, Loup, McPherson and 2 more	89 min
Aug 11, 5:17 PM MDT	Mesoscale Discussion	SPC	Burt, Butler, Cass, Cedar, Colfax, Cuming and 24 more	58 min
Aug 11, 5:29 PM MDT	Severe Thunderstorm Watch	SPC	Arthur, Blaine, Boyd, Brown, Cherry, Custer and 13 more	7 hr
Aug 10, 7:00 PM MDT	Severe Thunderstorm Watch	SPC	Beadle, Brookings, Brown, Brule, Buffalo, Campbell and 25 more	6 hr
Aug 10, 9:50 PM MDT	Mesoscale Discussion	SPC	Aurora, Beadle, Brookings, Brown, Brule, Buffalo and 18 more	85 min

Nearby

Mesoscale Discussions in South Dakota, 2016 Mesoscale Discussions in Nebraska, 2016 Every mesoscale discussion in 2016

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.