Alert archive / Alabama / Mesoscale Discussions in 2011

Mesoscale Discussion 2354

November 22, 201124 counties in Alabama; 24 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Nov 22, 2011, 11:38 AM CST for 24 counties in Alabama; 24 counties in Mississippi. It was in force for 37 min.

The area

The outline as issued.

The facts

Issued: Nov 22, 2011, 11:38 AM CST (17:38 UTC)
Expired: Nov 22, 2011, 12:15 PM CST
In force: 37 min
Issued by: the Storm Prediction Center

All 48 counties

Autauga County, AL, Bibb County, AL, Butler County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Coosa County, AL, Crenshaw County, AL, Dallas County, AL, Elmore County, AL, Greene County, AL, Hale County, AL, Lowndes County, AL, Marengo County, AL, Monroe County, AL, Montgomery County, AL, Perry County, AL, Pickens County, AL, Shelby County, AL, Sumter County, AL, Tuscaloosa County, AL, Washington County, AL, Wilcox County, AL, Clarke County, MS, Covington County, MS, Forrest County, MS, Greene County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Lawrence County, MS, Leake County, MS, Lincoln County, MS, Marion County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Perry County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Wayne County, MS, Winston County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 146 km from the middle of the area, began a volume at 17:37 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.

Tornado Watch 895Nov 22, 12:00 PM CST

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 5.6 hours before the alert went out and 155 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: 559 J/kg
Mixed-layer CIN: -44 J/kg
Mixed-layer LCL: 476 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 216 m²/s²
0-3 km storm-relative helicity: 252 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 3.7

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
Nov 22, 11:58 AM CST	Tornado Watch	SPC	Autauga, Barbour, Bibb, Bullock, Butler, Chambers and 28 more	8 hr
Nov 22, 12:49 PM CST	Mesoscale Discussion	SPC	Blount, Cherokee, DeKalb, Etowah, Jackson, Marshall	116 min
Nov 22, 2:40 PM CST	Mesoscale Discussion	SPC	Autauga, Bibb, Butler, Chilton, Choctaw, Clarke and 13 more	65 min
Nov 22, 3:24 PM CST	Mesoscale Discussion	SPC	Barbour, Bullock, Chambers, Clay, Dale, Elmore and 8 more	2 hr
Nov 22, 10:26 AM CST	Mesoscale Discussion	SPC	Adams, Amite, Copiah, Franklin, Jefferson, Jefferson Davis and 7 more	94 min

Nearby

Mesoscale Discussions in Alabama, 2011 Mesoscale Discussions in Mississippi, 2011 Every 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.