Alert archive / Nebraska / Mesoscale Discussions in 2020

Mesoscale Discussion 1285

July 19, 20205 states

The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2020, 6:48 PM MDT for 5 states. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: Jul 19, 2020, 6:48 PM MDT (00:48 UTC)
Expired: Jul 19, 2020, 8:45 PM MDT
In force: 117 min
Issued by: the Storm Prediction Center
Concerning: Severe thunderstorm watch 387

All 36 counties

Phillips County, CO, Sedgwick County, CO, Yuma County, CO, Cheyenne County, KS, Rawlins County, KS, Arthur County, NE, Box Butte County, NE, Chase County, NE, Cheyenne County, NE, Dawes County, NE, Deuel County, NE, Dundy County, NE, Frontier County, NE, Garden County, NE, Grant County, NE, Hayes County, NE, Hitchcock County, NE, Hooker County, NE, Keith County, NE, Lincoln County, NE, Logan County, NE, McPherson County, NE, Morrill County, NE, Perkins County, NE, Red Willow County, NE, Sheridan County, NE, Sioux County, NE, Thomas County, NE, Custer County, SD, Fall River County, SD, Lawrence County, SD, Oglala Lakota County, SD, Pennington County, SD, Crook County, WY, Niobrara County, WY, Weston County, WY

The radar

The North Platte radar (KLNX), 179 km from the middle of the area, began a volume at 00:48 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 nearest sounding before it

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 0.8 hours before the alert went out and 207 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: 817 J/kg
Mixed-layer CIN: -56 J/kg
Mixed-layer LCL: 1736 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 89 m²/s²
0-3 km storm-relative helicity: 286 m²/s²
Significant tornado parameter: 0.2
Supercell composite: 7.5

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
Jul 20, 2:51 PM MDT	Mesoscale Discussion	SPC	Phillips, Sedgwick	114 min
Jul 20, 1:14 AM MDT	Mesoscale Discussion	SPC	Clay, Cloud, Graham, Jewell, Marshall, Mitchell and 10 more	2 hr
Jul 19, 9:25 PM MDT	Mesoscale Discussion	SPC	Arthur, Blaine, Box Butte, Brown, Chase, Cherry and 25 more	65 min
Jul 20, 3:49 PM MDT	Severe Thunderstorm Watch	SPC	Arthur, Blaine, Brown, Chase, Cherry, Custer and 16 more	7 hr
Jul 20, 11:16 AM MDT	Mesoscale Discussion	SPC	Aurora, Beadle, Brown, Brule, Buffalo, Campbell and 31 more	119 min
Jul 20, 12:13 PM MDT	Severe Thunderstorm Watch	SPC	Beadle, Bennett, Brule, Buffalo, Custer, Dewey and 19 more	6 hr
Jul 20, 2:19 PM MDT	Mesoscale Discussion	SPC	Beadle, Bennett, Brule, Buffalo, Custer, Fall River and 17 more	116 min
Jul 20, 5:01 PM MDT	Mesoscale Discussion	SPC	Aurora, Beadle, Bennett, Brule, Buffalo, Clark and 12 more	89 min

Nearby

Mesoscale Discussions in Nebraska, 2020 Mesoscale Discussions in South Dakota, 2020 Mesoscale Discussions in Colorado, 2020 Every mesoscale discussion 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.