Alert archive / Louisiana / Special Weather Statements in 2021

Special Weather Statement, NWS New Orleans, LA

July 25, 2021Jefferson Parish, Louisiana

NWS New Orleans, LA issued this special weather statement at Jul 25, 2021, 10:53 AM CDT for Jefferson Parish, Louisiana. It was in force for 52 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 25, 2021, 10:53 AM CDT (15:53 UTC)
Expired: Jul 25, 2021, 11:45 AM CDT
In force: 52 min
Issued by: NWS New Orleans, LA

County Jefferson Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 3.9 hours before the alert went out and 91 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: 2216 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 793 m above ground
0-6 km bulk shear: 11 kt
0-1 km storm-relative helicity: -11 m²/s²
0-3 km storm-relative helicity: 0 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

The local office's own words before this special weather statement 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 special weather statement went out at Jul 25, 9:52 AM CDT, 1 hour 1 minute earlier.

Area forecast discussion, Jul 25, 9:52 AM CDT, 1 hour 1 minute before

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<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.
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In the hours before

Special weather statement, Jul 25, 10:53 AM CDT, 0 minutes before

Special Weather Statement
National Weather Service New Orleans LA
1053 AM CDT Sun Jul 25 2021

LAZ068-069-251645-
Lower Plaquemines-Lower Jefferson-
1053 AM CDT Sun Jul 25 2021

...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT EAST CENTRAL JEFFERSON
AND WEST CENTRAL PLAQUEMINES PARISHES...

At 1053 AM CDT, strong thunderstorms were clustered 9 miles southwest
of Port Sulphur. The storm is nearly stationary.

Winds in excess of 30 mph are possible with this storm.

Locations impacted include...
Port Sulphur.

Conditions in the atmosphere are such that weak, brief funnels may
form with these storms. These funnels are usually harmless, but on
rare occasions can briefly touch down and cause wind gusts over 50
mph. If a funnel approaches your location, move indoors.

Please contact the National Weather Service if you see a funnel.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 2942 8978 2936 8987 2943 8981 2941 8987
      2945 8982 2948 8984 2948 8985 2946 8989
      2943 8988 2942 8994 2949 8989 2949 8993
      2944 8993 2947 8997 2944 8999 2959 9006
      2955 8976 2938 8974 2935 8983
TIME...MOT...LOC 1553Z 144DEG 2KT 2942 8985

CAB

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 7:46 PM CDT	Special Weather Statement	LIX	Lafourche	44 min
Jul 25, 3:28 AM CDT	Special Marine Warning	LIX		62 min
Jul 25, 4:30 AM CDT	Special Marine Warning	LIX		60 min
Jul 25, 5:30 AM CDT	Special Marine Warning	LIX		60 min
Jul 25, 6:31 AM CDT	Special Marine Warning	LIX		59 min
Jul 25, 7:30 AM CDT	Special Marine Warning	LIX		60 min
Jul 25, 10:22 AM CDT	Special Marine Warning	LIX		98 min
Jul 25, 10:48 AM CDT	Special Marine Warning	LIX		57 min
Jul 25, 11:53 AM CDT	Special Weather Statement	LIX	Lafourche	37 min
Jul 25, 12:08 PM CDT	Special Weather Statement	LIX	Jefferson	52 min
Jul 25, 1:55 PM CDT	Special Weather Statement	LIX	Saint Tammany	95 min
Jul 25, 2:08 PM CDT	Areal Flood Advisory	LIX	Saint Tammany	80 min
Jul 25, 3:20 PM CDT	Heat Advisory	LIX	Assumption, East Baton Rouge, East Feliciana, Iberville, Orleans, Pointe Coupee and 9 more	28 hr
Jul 25, 1:47 PM CDT	Special Weather Statement	LIX	Pearl River	58 min

Nearby

Special Weather Statements in Louisiana, 2021 Every special weather statement in 2021

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.