Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 738

May 11, 20114 counties in Arkansas; McCurtain County, Oklahoma; 37 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 11, 2011, 2:51 PM CDT for 4 counties in Arkansas; McCurtain County, Oklahoma; 37 counties in Texas. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
May 11, 2011, 2:51 PM CDT (19:51 UTC)
Expired
May 11, 2011, 4:15 PM CDT
In force
84 min
Issued by
the Storm Prediction Center
All 42 counties

Lafayette County, AR, Little River County, AR, Miller County, AR, Sevier County, AR, McCurtain County, OK, Bosque County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Coryell County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Gregg County, TX, Hamilton County, TX, Henderson County, TX, Hill County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Lampasas County, TX, Llano County, TX, Marion County, TX, McLennan County, TX, Mills County, TX, Morris County, TX, Navarro County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, San Saba County, TX, Smith County, TX, Somervell County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 71 km from the middle of the area, began a volume at 19:54 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

Fort Worth, TX (KFWD), launched 12:00Z, 7.9 hours before the alert went out and 78 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, Fort Worth, TX at 12:00Z on 2011-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1949 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, Fort Worth, TX at 12:00Z on 2011-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 244 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
1949 J/kg
Mixed-layer CIN
-156 J/kg
Mixed-layer LCL
622 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
244 m²/s²
0-3 km storm-relative helicity
274 m²/s²
Significant tornado parameter
0.5
Supercell composite
4.8

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
May 11, 1:16 PM CDTSevere Thunderstorm WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more8 hr
May 11, 3:46 PM CDTSevere Thunderstorm WatchSPCClark, Conway, Garland, Hempstead, Hot Spring, Howard and 15 more8 hr
May 11, 6:35 PM CDTMesoscale DiscussionSPCBenton, Boone, Carroll, Clark, Conway, Crawford and 24 more55 min
May 11, 2:28 AM CDTMesoscale DiscussionSPCTexas92 min
May 11, 7:30 AM CDTMesoscale DiscussionSPCBeaver, Beckham, Ellis, Harmon, Harper, Roger Mills60 min
May 11, 12:33 PM CDTMesoscale DiscussionSPCAtoka, Coal, Creek, Haskell, Hughes, Johnston and 19 more87 min
May 11, 1:51 PM CDTMesoscale DiscussionSPCBeaver, Harper84 min
May 11, 6:02 PM CDTMesoscale DiscussionSPCEllis, Harper, Woods, Woodward88 min
May 11, 3:29 AM CDTSevere Thunderstorm WatchSPCAndrews, Armstrong, Bailey, Borden, Briscoe, Carson and 46 more8 hr
May 11, 9:56 AM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Comanche, Concho and 20 more94 min
May 11, 10:21 AM CDTSevere Thunderstorm WatchSPCBell, Bosque, Brown, Burnet, Callahan, Coleman and 52 more5 hr

Nearby

Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Oklahoma, 2011Every mesoscale discussion in 2011

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.