Alert archive / Louisiana / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 85, NWS New Orleans, LA

July 13, 2020Lafourche Parish, Terrebonne Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 13, 2020, 6:10 PM CDT for Lafourche Parish, Terrebonne Parish, Louisiana. It was in force for 35 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 13, 2020, 6:10 PM CDT (23:10 UTC)
Expired: Jul 13, 2020, 6:45 PM CDT
In force: 35 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, 11.2 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-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: 3369 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 676 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 32 m²/s²
0-3 km storm-relative helicity: 21 m²/s²
Significant tornado parameter: 0.3
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 Jul 13, 4:31 PM CDT, 1 hour 39 minutes earlier.

Area forecast discussion, Jul 13, 4:31 PM CDT, 1 hour 39 minutes before

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In the hours before

Special weather statement, Jul 13, 3:28 PM CDT, 2 hours 42 minutes before

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Special weather statement, Jul 13, 4:19 PM CDT, 1 hour 51 minutes before

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Special weather statement, Jul 13, 5:13 PM CDT, 57 minutes before

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      <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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Special weather statement, Jul 13, 5:28 PM CDT, 42 minutes before

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<body>
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      <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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Special weather statement, Jul 13, 5:39 PM CDT, 31 minutes before

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  <main class="wrap">
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      <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.
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Special weather statement, Jul 13, 6:03 PM CDT, 7 minutes before

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<body>
  <main class="wrap">
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      <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>
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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 12, 8:56 PM CDT	Special Marine Warning	LIX		94 min
Jul 12, 10:13 PM CDT	Special Marine Warning	LIX		92 min
Jul 13, 2:56 AM CDT	Special Marine Warning	LIX		34 min
Jul 13, 3:54 AM CDT	Excessive Heat Warning	LIX	Saint Bernard, Saint James, Saint John the Baptist	16 hr
Jul 13, 3:57 AM CDT	Special Marine Warning	LIX		33 min
Jul 13, 4:29 AM CDT	Special Marine Warning	LIX		31 min
Jul 13, 5:40 AM CDT	Special Marine Warning	LIX		22 min
Jul 13, 5:55 AM CDT	Special Weather Statement	LIX	Orleans	35 min
Jul 13, 6:59 AM CDT	Special Weather Statement	LIX	Orleans	31 min
Jul 13, 7:01 AM CDT	Special Marine Warning	LIX		44 min
Jul 13, 3:28 PM CDT	Special Weather Statement	LIX	Jefferson	32 min
Jul 13, 3:38 PM CDT	Special Marine Warning	LIX		37 min
Jul 13, 3:40 PM CDT	Heat Advisory	LIX	Assumption, East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Bernard and 7 more	28 hr
Jul 13, 4:19 PM CDT	Special Weather Statement	LIX	Lafourche	41 min
Jul 13, 5:13 PM CDT	Special Weather Statement	LIX	Jefferson	32 min
Jul 13, 5:28 PM CDT	Special Weather Statement	LIX	Saint Charles	47 min
Jul 13, 5:39 PM CDT	Special Weather Statement	LIX	Iberville	36 min
Jul 13, 6:03 PM CDT	Special Weather Statement	LIX	Lafourche	27 min
Jul 13, 6:41 PM CDT	Special Marine Warning	LIX		49 min
Jul 13, 6:45 PM CDT	Special Weather Statement	LIX	Terrebonne	30 min
Jul 12, 7:53 PM CDT	Special Weather Statement	LIX	Amite	37 min
Jul 12, 9:17 PM CDT	Special Weather Statement	LIX	Jackson	28 min
Jul 13, 2:09 AM CDT	Special Weather Statement	LIX	Jackson	66 min
Jul 13, 2:26 AM CDT	Special Weather Statement	LIX	Jackson	34 min
Jul 13, 5:53 AM CDT	Special Weather Statement	LIX	Harrison	37 min
Jul 13, 6:25 AM CDT	Special Weather Statement	LIX	Hancock	35 min
Jul 13, 6:56 AM CDT	Flash Flood Warning	LIX	Hancock, Harrison, Pearl River	2 hr
Jul 13, 7:55 AM CDT	Flash Flood Warning	LIX	Jackson	110 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2020 Every severe thunderstorm warning in 2020

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.