Alert archive / Louisiana / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 84, NWS New Orleans, LA

July 1, 2018Lafourche Parish, Terrebonne Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 1, 2018, 2:58 PM CDT for Lafourche Parish, Terrebonne Parish, Louisiana. It was in force for 62 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 1, 2018, 2:58 PM CDT (19:58 UTC)
Expired
Jul 1, 2018, 4:00 PM CDT
In force
62 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Lafourche Parish, LA, Terrebonne Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.0 hours before the alert went out and 128 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 2018-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 894 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 2018-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 43 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
894 J/kg
Mixed-layer CIN
-117 J/kg
Mixed-layer LCL
977 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
43 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Jul 1, 10:01 AM CDT, 4 hours 57 minutes earlier.

Area forecast discussion, Jul 1, 10:01 AM CDT, 4 hours 57 minutes before
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Hazardous weather outlook, Jul 1, 1:31 PM CDT, 1 hour 27 minutes before
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<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>
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In the hours before

Special weather statement, Jul 1, 2:04 PM CDT, 54 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.

IssuedProductOfficeCountiesLasted
Jun 30, 7:08 PM CDTSpecial Weather StatementLIXLivingston52 min
Jun 30, 7:24 PM CDTSpecial Marine WarningLIX66 min
Jun 30, 7:25 PM CDTSpecial Weather StatementLIXSaint Bernard95 min
Jun 30, 8:05 PM CDTSpecial Marine WarningLIX85 min
Jun 30, 8:32 PM CDTSpecial Weather StatementLIXSaint Tammany58 min
Jun 30, 9:33 PM CDTSpecial Marine WarningLIX27 min
Jun 30, 9:37 PM CDTSpecial Weather StatementLIXTangipahoa53 min
Jun 30, 9:49 PM CDTAreal Flood AdvisoryLIXSaint Tammany116 min
Jun 30, 10:41 PM CDTSpecial Marine WarningLIX34 min
Jun 30, 10:58 PM CDTSpecial Weather StatementLIXSaint Charles, Saint John the Baptist62 min
Jun 30, 11:35 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Bernard115 min
Jun 30, 11:47 PM CDTSpecial Marine WarningLIX58 min
Jul 1, 11:29 AM CDTSpecial Marine WarningLIX46 min
Jul 1, 12:18 PM CDTSpecial Marine WarningLIX57 min
Jul 1, 1:43 PM CDTHeat AdvisoryLIXSaint Bernard4 hr
Jul 1, 2:04 PM CDTSpecial Weather StatementLIXLafourche26 min
Jul 1, 2:06 PM CDTSpecial Marine WarningLIX39 min
Jul 1, 2:17 PM CDTSpecial Marine WarningLIX58 min
Jul 1, 3:50 PM CDTSpecial Marine WarningLIX55 min
Jul 1, 6:10 PM CDTSpecial Marine WarningLIX65 min
Jul 1, 6:29 PM CDTSpecial Marine WarningLIX91 min
Jun 30, 8:19 PM CDTSpecial Weather StatementLIXPearl River56 min
Jul 1, 4:11 PM CDTSpecial Weather StatementLIXJackson64 min
Jul 1, 6:08 PM CDTSpecial Weather StatementLIXHancock, Harrison82 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2018Every severe thunderstorm warning in 2018

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.