Alert archive / Texas / Mesoscale Discussions in 2017

Mesoscale Discussion 600

April 29, 201717 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2017, 7:34 PM CDT for 17 counties in Texas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: Apr 29, 2017, 7:34 PM CDT (00:34 UTC)
Expired: Apr 29, 2017, 8:30 PM CDT
In force: 56 min
Issued by: the Storm Prediction Center

Counties Anderson County, TX, Delta County, TX, Fannin County, TX, Franklin County, TX, Freestone County, TX, Henderson County, TX, Hopkins County, TX, Hunt County, TX, Kaufman County, TX, Lamar County, TX, Navarro County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Smith County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 127 km from the middle of the area, began a volume at 00:34 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

Fort Worth, TX (KFWD), launched 00:00Z, 0.6 hours before the alert went out and 132 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: 3 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 619 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 229 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 13.3

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
Apr 29, 8:57 PM CDT	Mesoscale Discussion	SPC	Bastrop, Brazos, Burleson, Caldwell, Fayette, Gonzales and 11 more	63 min
Apr 29, 9:38 PM CDT	Mesoscale Discussion	SPC	Bowie, Cass, Gregg, Harrison, Marion, Morris and 4 more	67 min
Apr 29, 10:23 PM CDT	Severe Thunderstorm Watch	SPC	Angelina, Bowie, Cass, Gregg, Harrison, Marion and 6 more	8 hr
Apr 29, 11:37 PM CDT	Mesoscale Discussion	SPC	Cass, Harrison, Marion, Nacogdoches, Panola, Rusk and 3 more	53 min
Apr 30, 1:14 AM CDT	Mesoscale Discussion	SPC	Chambers, Hardin, Jasper, Jefferson, Liberty, Newton and 2 more	91 min
Apr 30, 1:25 AM CDT	Mesoscale Discussion	SPC	Dallam, Sherman	6 hr

Nearby

Mesoscale Discussions in Texas, 2017 Every mesoscale discussion in 2017

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.