Alert archive / South Dakota / Mesoscale Discussions in 2015

Mesoscale Discussion 1653

August 9, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Aug 9, 2015, 1:05 PM CDT for 4 states. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued: Aug 9, 2015, 1:05 PM CDT (18:05 UTC)
Expired: Aug 9, 2015, 3:00 PM CDT
In force: 115 min
Issued by: the Storm Prediction Center
Chance of a watch: 95%

All 58 counties

Cherokee County, IA, Lyon County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sioux County, IA, Woodbury County, IA, Nobles County, MN, Pipestone County, MN, Rock County, MN, Antelope County, NE, Boone County, NE, Boyd County, NE, Burt County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Holt County, NE, Keya Paha County, NE, Knox County, NE, Madison County, NE, Pierce County, NE, Platte County, NE, Rock County, NE, Stanton County, NE, Thurston County, NE, Wayne County, NE, Wheeler County, NE, Aurora County, SD, Beadle County, SD, Bon Homme County, SD, Brookings County, SD, Brule County, SD, Charles Mix County, SD, Clark County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Gregory County, SD, Hamlin County, SD, Hanson County, SD, Hutchinson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Lincoln County, SD, McCook County, SD, Miner County, SD, Minnehaha County, SD, Moody County, SD, Sanborn County, SD, Turner County, SD, Union County, SD, Yankton County, SD

The radar

The Sioux Falls radar (KFSD), 73 km from the middle of the area, began a volume at 18:06 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 483Aug 9, 1:40 PM CDT

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 6.1 hours before the alert went out and 209 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: 57 J/kg
Mixed-layer CIN: -195 J/kg
Mixed-layer LCL: 1506 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 17 m²/s²
0-3 km storm-relative helicity: 85 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

<!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 8, 8:36 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Cass, Clarke, Decatur, Fremont and 7 more	114 min
Aug 8, 8:51 PM CDT	Severe Thunderstorm Watch	SPC	Adair, Adams, Cass, Clarke, Decatur, Fremont and 10 more	6 hr
Aug 8, 11:11 PM CDT	Mesoscale Discussion	SPC	Adams, Clarke, Decatur, Fremont, Montgomery, Page and 3 more	94 min
Aug 9, 1:37 AM CDT	Mesoscale Discussion	SPC	Adams, Appanoose, Cass, Clarke, Davis, Decatur and 8 more	83 min
Aug 9, 1:42 PM CDT	Severe Thunderstorm Watch	SPC	Cherokee, Ida, Lyon, O'Brien, Osceola, Plymouth and 2 more	9 hr
Aug 9, 4:03 PM CDT	Mesoscale Discussion	SPC	Cherokee, Ida, Lyon, O'Brien, Osceola, Plymouth and 2 more	117 min
Aug 8, 8:07 PM CDT	Mesoscale Discussion	SPC	Butte, Custer, Haakon, Jackson, Lawrence, Meade and 1 more	53 min

Nearby

Mesoscale Discussions in South Dakota, 2015 Mesoscale Discussions in Nebraska, 2015 Mesoscale Discussions in Iowa, 2015 Every mesoscale discussion in 2015

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.