Alert archive / Louisiana / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 167, NWS New Orleans, LA

July 26, 1999Saint Tammany Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 26, 1999, 3:15 PM CDT for Saint Tammany Parish, Louisiana. It was in force for 45 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
Jul 26, 1999, 3:15 PM CDT (20:15 UTC)
Expired
Jul 26, 1999, 4:00 PM CDT
In force
45 min
Issued by
NWS New Orleans, LA
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Saint Tammany Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.3 hours before the alert went out and 30 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 1999-07-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1398 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 12:00Z on 1999-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -32 square meters per square second.1939Sfc1 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
1398 J/kg
Mixed-layer CIN
-17 J/kg
Mixed-layer LCL
778 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
-32 m²/s²
0-3 km storm-relative helicity
-5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Jul 26, 1:26 PM CDT, 1 hour 49 minutes earlier.

Area forecast discussion, Jul 26, 1:26 PM CDT, 1 hour 49 minutes before
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In the hours before

Special weather statement, Jul 26, 10:00 AM CDT, 5 hours 15 minutes before
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Local storm report, Jul 26, 2:50 PM CDT, 25 minutes before
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      <div class="status" id="status">Temporary Notice</div>
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Local storm report, Jul 26, 2:53 PM CDT, 22 minutes before
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  <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.
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      <p class="small" id="detail">
        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
Jul 26, 3:49 PM CDTSevere Thunderstorm WarningLIXSaint Tammany41 min
Jul 26, 3:54 PM CDTSevere Thunderstorm WarningLIXWashington51 min
Jul 26, 6:16 PM CDTSevere Thunderstorm WarningLIXSaint Helena34 min
Jul 26, 2:32 PM CDTSevere Thunderstorm WarningLIXHarrison43 min
Jul 26, 2:48 PM CDTSevere Thunderstorm WarningLIXHancock27 min
Jul 26, 3:21 PM CDTSevere Thunderstorm WarningLIXHancock24 min
Jul 26, 6:21 PM CDTSevere Thunderstorm WarningLIXPike64 min
Jul 26, 6:51 PM CDTSevere Thunderstorm WarningLIXAmite44 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 1999Every severe thunderstorm warning in 1999

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.