Alert archive / Texas / Mesoscale Discussions in 2014

Mesoscale Discussion 338

April 13, 20148 counties in Arkansas; 6 parishes in Louisiana; 26 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2014, 2:34 PM CDT for 8 counties in Arkansas; 6 parishes in Louisiana; 26 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 13, 2014, 2:34 PM CDT (19:34 UTC)
Expired
Apr 13, 2014, 5:00 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 40 counties

Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Sevier County, AR, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Red River Parish, LA, Webster Parish, LA, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Falls County, TX, Franklin County, TX, Freestone County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Houston County, TX, Leon County, TX, Limestone County, TX, Marion County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 115 km from the middle of the area, began a volume at 19:37 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.

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 7.6 hours before the alert went out and 123 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, Shreveport, LA at 12:00Z on 2014-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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, Shreveport, LA at 12:00Z on 2014-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 218 square meters per square second.1939587897Sfc1 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
8 J/kg
Mixed-layer CIN
-436 J/kg
Mixed-layer LCL
552 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
218 m²/s²
0-3 km storm-relative helicity
205 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.

IssuedProductOfficeCountiesLasted
Apr 13, 4:13 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Crawford, Franklin and 9 more32 min
Apr 13, 4:27 PM CDTSevere Thunderstorm WatchSPCBaxter, Benton, Boone, Carroll, Madison, Marion and 3 more7 hr
Apr 13, 4:54 PM CDTMesoscale DiscussionSPCClark, Columbia, Hempstead, Howard, Lafayette, Little River and 4 more66 min
Apr 13, 5:13 PM CDTTornado WatchSPCColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 3 more6 hr
Apr 13, 6:01 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Madison, Marion and 3 more59 min
Apr 13, 6:25 PM CDTMesoscale DiscussionSPCClark, Conway, Crawford, Franklin, Garland, Hempstead and 15 more65 min
Apr 13, 12:26 PM CDTMesoscale DiscussionSPCWichita94 min
Apr 13, 1:43 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Comanche, Concho, Eastland and 7 more2 hr
Apr 13, 1:56 PM CDTTornado WatchSPCArcher, Clay, Cooke, Grayson, Jack, Montague and 3 more8 hr

Nearby

Mesoscale Discussions in Texas, 2014Mesoscale Discussions in Arkansas, 2014Mesoscale Discussions in Louisiana, 2014Every mesoscale discussion in 2014

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.