Alert archive / Louisiana / Mesoscale Discussions in 2011

Mesoscale Discussion 187

March 4, 2011Saint Tammany Parish, Tangipahoa Parish, Washington Parish, Louisiana; Hancock County, Harrison County, Pearl River County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Mar 4, 2011, 9:33 PM CST for Saint Tammany Parish, Tangipahoa Parish, Washington Parish, Louisiana; Hancock County, Harrison County, Pearl River County, Mississippi. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued
Mar 4, 2011, 9:33 PM CST (03:33 UTC)
Expired
Mar 4, 2011, 10:30 PM CST
In force
57 min
Issued by
the Storm Prediction Center

Counties Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, Hancock County, MS, Harrison County, MS, Pearl River County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 3.6 hours before the alert went out and 36 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-pSkew-T log-p diagram, Slidell Radar S, LA at 00:00Z on 2011-03-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 87 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 2011-03-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 379 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
87 J/kg
Mixed-layer CIN
-61 J/kg
Mixed-layer LCL
552 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
379 m²/s²
0-3 km storm-relative helicity
521 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

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.

IssuedProductOfficeCountiesLasted
Mar 5, 8:40 AM CSTMesoscale DiscussionSPCAcadia, Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia and 23 more65 min
Mar 5, 8:54 AM CSTTornado WatchSPCAcadia, Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia and 23 more7 hr
Mar 5, 11:12 AM CSTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Jefferson, Lafourche and 12 more93 min
Mar 5, 1:31 PM CSTMesoscale DiscussionSPCPlaquemines, Saint Bernard89 min

Nearby

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