Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 1890

October 26, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Oct 26, 2015, 1:32 AM CDT for 4 states. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued: Oct 26, 2015, 1:32 AM CDT (06:32 UTC)
Expired: Oct 26, 2015, 3:30 AM CDT
In force: 118 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

Counties Baldwin County, AL, Mobile County, AL, Escambia County, FL, Okaloosa County, FL, Santa Rosa County, FL, Saint Bernard Parish, LA, George County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Pearl River County, MS, Stone County, MS

The radar

The Mobile radar (KMOB), 107 km from the middle of the area, began a volume at 06:33 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.

Tornado Watch 522Oct 26, 2:05 AM CDT

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 6.5 hours before the alert went out and 139 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: 318 J/kg
Mixed-layer CIN: 0 J/kg
Mixed-layer LCL: 488 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 468 m²/s²
0-3 km storm-relative helicity: 554 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 3.6

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.

Issued	Product	Office	Counties	Lasted
Oct 25, 7:53 PM CDT	Mesoscale Discussion	SPC	Baldwin, Escambia, Mobile	3 hr
Oct 26, 7:32 AM CDT	Mesoscale Discussion	SPC	Baldwin, Mobile	118 min
Oct 25, 7:12 PM CDT	Tornado Watch	SPC	Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 3 more	7 hr
Oct 25, 10:15 PM CDT	Mesoscale Discussion	SPC	Jefferson, Lafourche, Orleans, Plaquemines, Saint Bernard, Saint Charles and 4 more	2 hr
Oct 26, 2:05 AM CDT	Tornado Watch	SPC	Saint Bernard	7 hr

Nearby

Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Florida, 2015 Mesoscale Discussions in Alabama, 2015 Every mesoscale discussion in 2015

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.