Alert archive / Mississippi / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 176, NWS New Orleans, LA

October 15, 2009Walthall County, Mississippi

NWS New Orleans, LA issued this severe thunderstorm warning at Oct 15, 2009, 3:28 PM CDT for Walthall County, Mississippi. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Oct 15, 2009, 3:28 PM CDT (20:28 UTC)
Expired: Oct 15, 2009, 4:15 PM CDT
In force: 47 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon

County Walthall County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 8.5 hours before the alert went out and 130 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: 1438 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 481 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 131 m²/s²
0-3 km storm-relative helicity: 151 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 7.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS New Orleans, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Oct 15, 12:32 PM CDT, 2 hours 56 minutes earlier.

Area forecast discussion, Oct 15, 12:32 PM CDT, 2 hours 56 minutes before

<!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>

Hazardous weather outlook, Oct 15, 10:40 AM CDT, 4 hours 48 minutes before

<!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>

The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Oct 14, 10:07 PM CDT	Dense Fog Advisory	LIX	East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Helena, Washington and 2 more	10 hr
Oct 15, 4:20 PM CDT	Small Craft Advisory	LIX		3 days
Oct 15, 4:55 PM CDT	Severe Thunderstorm Warning	LIX	Walthall	31 min
Oct 15, 6:05 PM CDT	Severe Thunderstorm Warning	LIX	Pearl River	28 min

Nearby

Severe Thunderstorm Warnings in Mississippi, 2009 Every severe thunderstorm warning 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.