Alert archive / South Dakota / Mesoscale Discussions in 2016

Mesoscale Discussion 1071

June 28, 2016Custer County, Lawrence County, Pennington County, South Dakota; Crook County, Wyoming

The Storm Prediction Center issued this mesoscale discussion at Jun 28, 2016, 11:32 AM MDT for Custer County, Lawrence County, Pennington County, South Dakota; Crook County, Wyoming. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued: Jun 28, 2016, 11:32 AM MDT (17:32 UTC)
Expired: Jun 28, 2016, 12:30 PM MDT
In force: 58 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Custer County, SD, Lawrence County, SD, Pennington County, SD, Crook County, WY

The radar

The Rapid City radar (KUDX), 109 km from the middle of the area, began a volume at 17:32 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 304Jun 28, 1:40 PM MDT

The nearest sounding before it

Rapid City, SD (KRAP), launched 12:00Z, 5.5 hours before the alert went out and 107 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: 306 J/kg
Mixed-layer CIN: -199 J/kg
Mixed-layer LCL: 1761 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 56 m²/s²
0-3 km storm-relative helicity: 81 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
Jun 28, 12:55 PM MDT	Mesoscale Discussion	SPC	Custer, Fall River, Lawrence, Oglala Lakota	95 min
Jun 28, 1:37 PM MDT	Severe Thunderstorm Watch	SPC	Bennett, Butte, Custer, Fall River, Haakon, Jackson and 6 more	7 hr
Jun 28, 4:26 PM MDT	Mesoscale Discussion	SPC	Fall River	94 min
Jun 27, 6:44 PM MDT	Mesoscale Discussion	SPC	Goshen, Laramie, Platte	61 min

Nearby

Mesoscale Discussions in South Dakota, 2016 Mesoscale Discussions in Wyoming, 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.