Alert archive / Texas / Mesoscale Discussions in 2018

Mesoscale Discussion 1728

December 26, 201848 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 26, 2018, 4:58 PM CST for 48 counties in Texas. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued: Dec 26, 2018, 4:58 PM CST (22:58 UTC)
Expired: Dec 26, 2018, 6:00 PM CST
In force: 62 min
Issued by: the Storm Prediction Center
Chance of a watch: 95%

All 48 counties

Archer County, TX, Baylor County, TX, Bell County, TX, Blanco County, TX, Bosque County, TX, Brown County, TX, Burnet County, TX, Callahan County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Coryell County, TX, Eastland County, TX, Erath County, TX, Falls County, TX, Gillespie County, TX, Hamilton County, TX, Haskell County, TX, Hill County, TX, Hood County, TX, Jack County, TX, Johnson County, TX, Jones County, TX, Kimble County, TX, Knox County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, McLennan County, TX, Menard County, TX, Milam County, TX, Mills County, TX, Palo Pinto County, TX, Parker County, TX, Runnels County, TX, San Saba County, TX, Schleicher County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Sutton County, TX, Taylor County, TX, Throckmorton County, TX, Travis County, TX, Williamson County, TX, Wise County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 65 km from the middle of the area, began a volume at 22:58 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, 11.0 hours before the alert went out and 182 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: 53 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 497 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 255 m²/s²
0-3 km storm-relative helicity: 164 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.

Issued	Product	Office	Counties	Lasted
Dec 26, 11:33 AM CST	Mesoscale Discussion	SPC	Bailey, Borden, Briscoe, Castro, Coke, Crockett and 24 more	117 min
Dec 26, 12:28 PM CST	Mesoscale Discussion	SPC	Archer, Baylor, Brown, Callahan, Coleman, Comanche and 22 more	2 hr
Dec 26, 12:44 PM CST	Severe Thunderstorm Watch	SPC	Armstrong, Borden, Briscoe, Carson, Castro, Childress and 40 more	6 hr
Dec 26, 2:11 PM CST	Tornado Watch	SPC	Bell, Bosque, Brown, Burnet, Callahan, Coleman and 29 more	10 hr
Dec 26, 3:21 PM CST	Mesoscale Discussion	SPC	Armstrong, Borden, Briscoe, Castro, Childress, Coke and 34 more	84 min
Dec 26, 4:43 PM CST	Mesoscale Discussion	SPC	Archer, Baylor, Bell, Blanco, Bosque, Brown and 42 more	2 hr
Dec 26, 5:06 PM CST	Severe Thunderstorm Watch	SPC	Archer, Baylor, Clay, Foard, Hardeman, Knox and 2 more	4 hr
Dec 26, 5:48 PM CST	Tornado Watch	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Caldwell and 17 more	8 hr

Nearby

Mesoscale Discussions in Texas, 2018 Every 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; radar from the NEXRAD Level II archive.