Alert archive / Mississippi / Mesoscale Discussions in 2009

Mesoscale Discussion 367

April 2, 200919 parishes in Louisiana; 46 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 2, 2009, 11:51 AM CDT for 19 parishes in Louisiana; 46 counties in Mississippi. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued: Apr 2, 2009, 11:51 AM CDT (16:51 UTC)
Expired: Apr 2, 2009, 1:15 PM CDT
In force: 84 min
Issued by: the Storm Prediction Center

All 65 counties

Ascension Parish, LA, Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Jefferson Parish, LA, Lafourche Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Saint Charles Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, St. Mary Parish, LA, Tangipahoa Parish, LA, Terrebonne Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, Amite County, MS, Attala County, MS, Carroll County, MS, Choctaw County, MS, Claiborne County, MS, Clarke County, MS, Clay County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Hinds County, MS, Holmes 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, Madison County, MS, Marion County, MS, Montgomery County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Webster County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 97 km from the middle of the area, began a volume at 16:54 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 nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 4.9 hours before the alert went out and 100 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: 1573 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 460 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 164 m²/s²
0-3 km storm-relative helicity: 211 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.7

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
Apr 2, 1:32 AM CDT	Mesoscale Discussion	SPC	Bossier, Caddo, De Soto, Red River, Webster	58 min
Apr 2, 4:43 AM CDT	Severe Thunderstorm Watch	SPC	Beauregard, Bienville, Bossier, Caddo, Caldwell, Claiborne and 14 more	6 hr
Apr 2, 5:57 AM CDT	Mesoscale Discussion	SPC	Plaquemines	63 min
Apr 2, 7:36 AM CDT	Mesoscale Discussion	SPC	Allen, Beauregard, Bienville, Bossier, Caddo, Caldwell and 15 more	54 min
Apr 2, 8:01 AM CDT	Mesoscale Discussion	SPC	Avoyelles, Catahoula, Concordia, East Carroll, East Feliciana, Franklin and 7 more	59 min
Apr 2, 9:24 AM CDT	Tornado Watch	SPC	Ascension, Assumption, Catahoula, Concordia, East Baton Rouge, East Carroll and 25 more	7 hr
Apr 2, 3:56 PM CDT	Severe Thunderstorm Watch	SPC	East Carroll, West Carroll	4 hr
Apr 2, 6:29 AM CDT	Tornado Watch	SPC	George, Greene, Perry, Stone, Wayne	8 hr
Apr 2, 10:53 AM CDT	Tornado Watch	SPC	Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more	4 hr
Apr 2, 1:09 PM CDT	Mesoscale Discussion	SPC	Clarke, George, Greene, Harrison, Jackson, Kemper and 6 more	66 min
Apr 2, 1:33 PM CDT	Tornado Watch	SPC	George, Greene, Perry, Stone, Wayne	5 hr
Apr 2, 3:36 PM CDT	Mesoscale Discussion	SPC	Attala, Bolivar, Carroll, Claiborne, Coahoma, Copiah and 20 more	54 min
Apr 2, 5:36 PM CDT	Mesoscale Discussion	SPC	Alcorn, Attala, Benton, Calhoun, Carroll, Chickasaw and 25 more	84 min
Apr 2, 6:21 PM CDT	Tornado Watch	SPC	Alcorn, Benton, Calhoun, Chickasaw, DeSoto, Itawamba and 9 more	3 hr

Nearby

Mesoscale Discussions in Mississippi, 2009 Mesoscale Discussions in Louisiana, 2009 Every mesoscale discussion in 2009

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.