Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 296

April 30, 2018Beaver County, Oklahoma; 28 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2018, 3:10 PM CDT for Beaver County, Oklahoma; 28 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 30, 2018, 3:10 PM CDT (20:10 UTC)
Expired
Apr 30, 2018, 5:45 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 29 counties

Beaver County, OK, Armstrong County, TX, Borden County, TX, Briscoe County, TX, Carson County, TX, Childress County, TX, Collingsworth County, TX, Crosby County, TX, Dawson County, TX, Dickens County, TX, Donley County, TX, Floyd County, TX, Garza County, TX, Gray County, TX, Hale County, TX, Hall County, TX, Hansford County, TX, Hemphill County, TX, Hutchinson County, TX, Lipscomb County, TX, Lubbock County, TX, Lynn County, TX, Martin County, TX, Motley County, TX, Ochiltree County, TX, Roberts County, TX, Swisher County, TX, Terry County, TX, Wheeler County, TX

The watches that followed

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

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 8.2 hours before the alert went out and 109 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, Amarillo Airport, TX at 12:00Z on 2018-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 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, Amarillo Airport, TX at 12:00Z on 2018-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 148 square meters per square second.193958Sfc1 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1264 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
148 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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.

IssuedProductOfficeCountiesLasted
Apr 30, 3:47 PM CDTSevere Thunderstorm WatchSPCBeaver, Beckham, Ellis, Greer, Harmon, Harper and 1 more7 hr

Nearby

Mesoscale Discussions in Texas, 2018Mesoscale Discussions in Oklahoma, 2018Every mesoscale discussion in 2018

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.