Alert archive / Louisiana / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 76, NWS New Orleans, LA

April 13, 2009West Feliciana Parish, Louisiana; Wilkinson County, Mississippi

NWS New Orleans, LA issued this severe thunderstorm warning at Apr 13, 2009, 4:33 PM CDT for West Feliciana Parish, Louisiana; Wilkinson County, Mississippi. It was in force for 61 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
Apr 13, 2009, 4:33 PM CDT (21:33 UTC)
Expired
Apr 13, 2009, 5:34 PM CDT
In force
61 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon

Counties West Feliciana Parish, LA, Wilkinson County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 9.6 hours before the alert went out and 181 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 12:00Z on 2009-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2009-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -136 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1276 m above ground
0-6 km bulk shear
66 kt
0-1 km storm-relative helicity
-136 m²/s²
0-3 km storm-relative helicity
57 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.6

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 Apr 13, 3:39 PM CDT, 54 minutes earlier.

Area forecast discussion, Apr 13, 3:39 PM CDT, 54 minutes before
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Hazardous weather outlook, Apr 13, 10:15 AM CDT, 6 hours 18 minutes before
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      <div class="status" id="status">Temporary Notice</div>
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In the hours before

Special weather statement, Apr 13, 3:45 PM CDT, 48 minutes before
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  <link rel="stylesheet" href="index.css">
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<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.
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      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 12, 7:26 PM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, West Baton Rouge21 min
Apr 12, 8:32 PM CDTSevere Thunderstorm WarningLIXEast Feliciana15 min
Apr 12, 9:47 PM CDTSevere Thunderstorm WarningLIXLivingston, Saint Helena, Tangipahoa, Washington58 min
Apr 12, 11:36 PM CDTSpecial Marine WarningLIX24 min
Apr 13, 12:17 AM CDTSpecial Marine WarningLIX43 min
Apr 13, 12:25 AM CDTSevere Thunderstorm WarningLIXSaint Tammany35 min
Apr 13, 6:33 AM CDTDense Fog AdvisoryLIXAssumption, East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Helena and 5 more2 hr
Apr 13, 8:57 AM CDTSpecial Marine WarningLIX63 min
Apr 13, 9:52 AM CDTRiver Flood WarningLIXTangipahoa4 days
Apr 13, 9:58 AM CDTSpecial Marine WarningLIX92 min
Apr 13, 9:59 AM CDTRiver Flood WarningLIXSaint Tammany5 days
Apr 13, 11:27 AM CDTSpecial Marine WarningLIX93 min
Apr 13, 1:19 PM CDTSpecial Marine WarningLIX86 min
Apr 13, 2:05 PM CDTSpecial Marine WarningLIX85 min
Apr 13, 3:44 PM CDTSmall Craft AdvisoryLIX18 hr
Apr 13, 3:54 PM CDTSevere Thunderstorm WarningLIXWashington66 min
Apr 12, 7:36 PM CDTSevere Thunderstorm WarningLIXAmite, Pike, Walthall54 min
Apr 12, 7:46 PM CDTFlash Flood WarningLIXAmite, Pike2 hr
Apr 12, 11:43 PM CDTSevere Thunderstorm WarningLIXPearl River62 min
Apr 13, 3:14 AM CDTSevere Thunderstorm WarningLIXHarrison23 min
Apr 13, 9:52 AM CDTRiver Flood WarningLIXPike11 hr
Apr 13, 1:44 PM CDTRiver Flood WarningLIXHarrison34 hr

Nearby

Severe Thunderstorm Warnings in Louisiana, 2009Severe Thunderstorm Warnings in Mississippi, 2009Every 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.