Alert archive / Texas / Mesoscale Discussions in 2020

Mesoscale Discussion 481

April 27, 202014 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2020, 6:33 PM CDT for 14 counties in Texas. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued
Apr 27, 2020, 6:33 PM CDT (23:33 UTC)
Expired
Apr 27, 2020, 8:30 PM CDT
In force
117 min
Issued by
the Storm Prediction Center

Counties Coke County, TX, Crockett County, TX, Glasscock County, TX, Howard County, TX, Irion County, TX, Midland County, TX, Mitchell County, TX, Nolan County, TX, Reagan County, TX, Sterling County, TX, Terrell County, TX, Tom Green County, TX, Upton County, TX, Val Verde County, TX

The radar

The San Angelo radar (KSJT), 113 km from the middle of the area, began a volume at 23:32 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 nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 11.6 hours before the alert went out and 159 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, Midland Regional, TX at 12:00Z on 2020-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 368 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, Midland Regional, TX at 12:00Z on 2020-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 267 square meters per square second.19395878Sfc1 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
368 J/kg
Mixed-layer CIN
-567 J/kg
Mixed-layer LCL
2150 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
267 m²/s²
0-3 km storm-relative helicity
380 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.

IssuedProductOfficeCountiesLasted
Apr 27, 2:30 PM CDTMesoscale DiscussionSPCBrewster, Crane, Glasscock, Midland, Pecos, Reagan and 2 more2 hr
Apr 27, 3:10 PM CDTSevere Thunderstorm WatchSPCCrockett, Glasscock, Irion, Midland, Pecos, Reagan and 3 more6 hr

Nearby

Mesoscale Discussions in Texas, 2020Every 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.