Alert archive / Louisiana / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 126, NWS New Orleans, LA

August 19, 2017Livingston Parish, Tangipahoa Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Aug 19, 2017, 3:46 PM CDT for Livingston Parish, Tangipahoa Parish, Louisiana. It was in force for 29 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
Aug 19, 2017, 3:46 PM CDT (20:46 UTC)
Expired
Aug 19, 2017, 4:15 PM CDT
In force
29 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Livingston Parish, LA, Tangipahoa Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.8 hours before the alert went out and 89 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 2017-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1945 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 2017-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 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
1945 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
978 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
21 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 Aug 19, 12:13 PM CDT, 3 hours 33 minutes earlier.

Area forecast discussion, Aug 19, 12:13 PM CDT, 3 hours 33 minutes before
Area Forecast Discussion
National Weather Service New Orleans LA
1213 PM CDT Sat Aug 19 2017

.AVIATION...

VFR conditions will prevail at all of the terminals through the
forecast period. The biggest concern will be thunderstorms
developing between 18z and 00z today that could impact any of the
terminals for brief periods of time. Have included VCTS wording to
reflect this risk at most of the terminals. However, at KHUM, have
included a couple of hours of MVFR visbilities and prevailing
thunder in a tempo group as rainfall probabilities currently are
highest at this terminal for this afternoon. The biggest concern
with any convection will be strong gusty winds and wind shear near
the thunderstorms as well as periods of IFR visibility
restrictions as the storms move through.  32

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  74  92  74  91 /  20  30  20  30
BTR  74  93  76  92 /  10  30  20  40
ASD  75  93  76  90 /  10  30  20  40
MSY  77  93  78  90 /  10  30  20  50
GPT  76  92  78  89 /  10  30  20  40
PQL  74  93  77  90 /  10  30  20  40

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&
Hazardous weather outlook, Aug 19, 11:03 AM CDT, 4 hours 43 minutes before
Hazardous Weather Outlook
National Weather Service New Orleans LA
1103 AM CDT Sat Aug 19 2017

GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037-
039-040-046>050-056>072-MSZ068>071-077-080>082-200415-
Lake Pontchartrain and Lake Maurepas-Mississippi Sound-
Lake Borgne-Chandeleur Sound-Breton Sound-
Coastal Waters from Port Fourchon LA to Lower Atchafalaya River
LA out 20 nm-
Coastal waters from the Southwest Pass of the Mississippi River
to Port Fourchon Louisiana out 20 NM-
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm-
Coastal waters from Pascagoula Mississippi to Stake Island out
20 NM-
Coastal waters from Port Fourchon Louisiana to Lower Atchafalaya
River LA from 20 to 60 NM-
Coastal waters from Southwest Pass of the Mississippi River to
Port Fourchon Louisiana from 20 to 60 NM-
Coastal Waters from Stake Island LA to Southwest Pass of the
Mississippi River from 20 to 60 nm-
Coastal waters from Pascagoula Mississippi to Stake Island
Louisiana out 20 to 60 NM-Pointe Coupee-West Feliciana-
East Feliciana-St. Helena-Washington-St. Tammany-Iberville-
West Baton Rouge-East Baton Rouge-Ascension-Livingston-Assumption-
St. James-St. John The Baptist-Upper Lafourche-St. Charles-
Upper Jefferson-Orleans-Upper Plaquemines-Upper St. Bernard-
Upper Terrebonne-Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Wilkinson-Amite-Pike-Walthall-Pearl River-
Hancock-Harrison-Jackson-
1103 AM CDT Sat Aug 19 2017

This Hazardous Weather Outlook is for portions of Southeast
Louisiana...South Mississippi and the adjacent coastal waters.

.DAY ONE...This Afternoon and Tonight

Afternoon showers and thunderstorms are expected. A few could be
strong to possibly severe with damaging downburst winds. Frequent
lightning and heavy downpours with localized flooding are a
potential as well.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Daily afternoon thunderstorms are expected through next week. A
few of the storms each day could become strong, producing gusty
winds, frequent lightning and heavy downpours that could result
in localized street flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

32

In the hours before

Special weather statement, Aug 19, 3:19 PM CDT, 27 minutes before
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Special weather statement, Aug 19, 3:30 PM CDT, 16 minutes before
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</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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Special weather statement, Aug 19, 3:32 PM CDT, 14 minutes before
Special Weather Statement
National Weather Service New Orleans LA
332 PM CDT SAT AUG 19 2017

LAZ040-072-192100-
Southern Tangipahoa-St. Tammany-
332 PM CDT SAT AUG 19 2017

...A STRONG THUNDERSTORM WILL AFFECT WEST CENTRAL ST. TAMMANY AND
SOUTHERN TANGIPAHOA PARISHES...

At 331 PM CDT, a strong thunderstorm was located near Robert, or 9
miles west of Covington, moving southwest at 15 mph.

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

Locations impacted include...
Hammond, Ponchatoula and Robert.

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 3059 9025 3048 9016 3031 9038 3049 9052
TIME...MOT...LOC 2031Z 057DEG 14KT 3051 9026

32
Special weather statement, Aug 19, 3:38 PM CDT, 8 minutes before
Special Weather Statement
National Weather Service New Orleans LA
338 PM CDT SAT AUG 19 2017

MSZ082-192130-
Jackson-
338 PM CDT SAT AUG 19 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN JACKSON COUNTY...

At 338 PM CDT, a strong thunderstorm was located 8 miles northwest of
Wade, or 13 miles south of Lucedale, moving south at 10 mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Escatawpa, Vancleave, Wade and Hurley.

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 3051 8851 3054 8882 3073 8876 3073 8853
TIME...MOT...LOC 2038Z 006DEG 9KT 3074 8864

32
Special weather statement, Aug 19, 3:42 PM CDT, 4 minutes before
Special Weather Statement
National Weather Service New Orleans LA
342 PM CDT SAT AUG 19 2017

LAZ040-MSZ077-080-192115-
St. Tammany-Hancock-Pearl River-
342 PM CDT SAT AUG 19 2017

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHEASTERN ST.
TAMMANY PARISH...SOUTHERN HANCOCK AND SOUTH CENTRAL PEARL RIVER
COUNTIES...

At 342 PM CDT, radar indicated strong thunderstorms were located
along a line extending from near Picayune to near Shoreline Park.
Movement was south at 30 mph.

Winds in excess of 40 mph are possible with these storms.

Locations impacted include...
Slidell, Picayune, Waveland, Diamondhead, Pearl River, Pearlington,
Shoreline Park, Stennis Space Center, Lacombe, Kiln and Slidell
Airport.

Torrential rainfall is also occurring with these storms, 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 3056 8973 3036 8937 3018 8946 3018 8947
      3019 8946 3019 8948 3018 8970 3017 8971
      3018 8972 3021 8980 3023 8985 3025 8987
      3026 8990 3025 8992 3026 8995
TIME...MOT...LOC 2042Z 017DEG 26KT 3048 8971 3035 8944

32
Special weather statement, Aug 19, 3:44 PM CDT, 2 minutes before
Special Weather Statement
National Weather Service New Orleans LA
344 PM CDT SAT AUG 19 2017

MSZ068>070-192130-
Pike-Wilkinson-Amite-
344 PM CDT SAT AUG 19 2017

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT SOUTHERN PIKE...
WILKINSON AND AMITE COUNTIES...

At 344 PM CDT, radar indicated strong thunderstorms were located
along a line extending from 6 miles south of Jonesville to Slocum to
6 miles west of Gloster to 7 miles southwest of Mccomb. Movement was
southeast at 15 mph.

Winds in excess of 30 mph are possible with these storms.

Locations impacted include...
Liberty, Magnolia, Centreville, Woodville, Gloster, Osyka, Gillsberg
and Mccomb Airport.

Torrential rainfall is also occurring with these storms, 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 3124 9116 3126 9053 3100 9026 3100 9117
      3106 9152 3116 9160 3124 9156 3122 9153
      3123 9149 3126 9148 3128 9150 3130 9147
TIME...MOT...LOC 2044Z 329DEG 14KT 3154 9186 3128 9167 3118 9112 3120
9057

32

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 8:31 AM CDTSpecial Marine WarningLIX29 min
Aug 19, 8:43 AM CDTSpecial Marine WarningLIX62 min
Aug 19, 9:39 AM CDTSpecial Marine WarningLIX66 min
Aug 19, 9:41 AM CDTSpecial Marine WarningLIX64 min
Aug 19, 10:43 AM CDTSpecial Marine WarningLIX32 min
Aug 19, 12:28 PM CDTSpecial Marine WarningLIX47 min
Aug 19, 12:30 PM CDTSpecial Marine WarningLIX45 min
Aug 19, 12:37 PM CDTSpecial Marine WarningLIX38 min
Aug 19, 1:02 PM CDTSpecial Weather StatementLIXWashington28 min
Aug 19, 1:07 PM CDTSpecial Marine WarningLIX38 min
Aug 19, 1:08 PM CDTSpecial Marine WarningLIX52 min
Aug 19, 1:10 PM CDTSpecial Marine WarningLIX50 min
Aug 19, 1:16 PM CDTSpecial Weather StatementLIXJefferson29 min
Aug 19, 1:33 PM CDTSpecial Marine WarningLIX42 min
Aug 19, 1:53 PM CDTSpecial Marine WarningLIX52 min
Aug 19, 1:55 PM CDTSpecial Marine WarningLIX50 min
Aug 19, 1:56 PM CDTSpecial Marine WarningLIX49 min
Aug 19, 2:06 PM CDTSpecial Weather StatementLIXWashington39 min
Aug 19, 2:28 PM CDTSpecial Marine WarningLIX47 min
Aug 19, 2:42 PM CDTSpecial Marine WarningLIX48 min
Aug 19, 2:45 PM CDTSpecial Weather StatementLIXSaint Tammany45 min
Aug 19, 2:48 PM CDTSevere Thunderstorm WarningLIXTangipahoa27 min
Aug 19, 2:57 PM CDTSpecial Weather StatementLIXLafourche33 min
Aug 19, 2:59 PM CDTSpecial Weather StatementLIXJefferson31 min
Aug 19, 3:16 PM CDTSpecial Marine WarningLIX44 min
Aug 19, 3:17 PM CDTSpecial Marine WarningLIX43 min
Aug 19, 3:19 PM CDTSpecial Marine WarningLIX26 min
Aug 19, 3:19 PM CDTSpecial Weather StatementLIXSaint John the Baptist26 min
Aug 19, 3:30 PM CDTSpecial Weather StatementLIXTerrebonne45 min
Aug 19, 3:32 PM CDTSpecial Weather StatementLIXTangipahoa28 min
Aug 19, 3:33 PM CDTSevere Thunderstorm WarningLIXSaint Helena, Tangipahoa27 min
Aug 19, 3:48 PM CDTSpecial Marine WarningLIX42 min
Aug 19, 3:51 PM CDTSpecial Marine WarningLIX24 min
Aug 19, 4:02 PM CDTSpecial Weather StatementLIXSaint Helena28 min
Aug 19, 4:05 PM CDTSpecial Weather StatementLIXTerrebonne55 min
Aug 19, 4:07 PM CDTSpecial Marine WarningLIX53 min
Aug 19, 4:23 PM CDTSpecial Marine WarningLIX67 min
Aug 19, 4:26 PM CDTSevere Thunderstorm WarningLIXJefferson, Lafourche, Saint Charles34 min
Aug 19, 4:49 PM CDTSpecial Weather StatementLIXSaint Charles26 min
Aug 19, 4:52 PM CDTSpecial Weather StatementLIXAscension, Saint James53 min
Aug 19, 5:04 PM CDTSpecial Marine WarningLIX56 min
Aug 19, 5:08 PM CDTSpecial Weather StatementLIXEast Feliciana52 min
Aug 19, 5:15 PM CDTSpecial Weather StatementLIXLafourche30 min
Aug 19, 5:24 PM CDTSpecial Weather StatementLIXAssumption, Iberville51 min
Aug 19, 5:27 PM CDTSpecial Weather StatementLIXSaint James33 min
Aug 19, 5:52 PM CDTSevere Thunderstorm WarningLIXAssumption23 min
Aug 19, 5:54 PM CDTSevere Thunderstorm WarningLIXAssumption, Lafourche, Terrebonne36 min
Aug 19, 6:20 PM CDTSpecial Weather StatementLIXJefferson, Lafourche40 min
Aug 19, 12:38 PM CDTSpecial Weather StatementLIXJackson37 min
Aug 19, 12:40 PM CDTSpecial Weather StatementLIXJackson50 min
Aug 19, 1:00 PM CDTSpecial Weather StatementLIXJackson30 min
Aug 19, 1:15 PM CDTSpecial Weather StatementLIXHarrison30 min
Aug 19, 2:08 PM CDTSpecial Weather StatementLIXJackson52 min
Aug 19, 2:26 PM CDTSpecial Weather StatementLIXPearl River49 min
Aug 19, 2:30 PM CDTSpecial Weather StatementLIXHancock45 min
Aug 19, 2:38 PM CDTSevere Thunderstorm WarningLIXHancock, Pearl River37 min
Aug 19, 2:40 PM CDTSevere Thunderstorm WarningLIXHancock35 min
Aug 19, 2:56 PM CDTSpecial Weather StatementLIXStone34 min
Aug 19, 3:01 PM CDTSpecial Weather StatementLIXPike44 min
Aug 19, 3:08 PM CDTSpecial Weather StatementLIXHancock37 min
Aug 19, 3:12 PM CDTSpecial Weather StatementLIXHancock33 min
Aug 19, 3:38 PM CDTSpecial Weather StatementLIXJackson52 min
Aug 19, 3:42 PM CDTSpecial Weather StatementLIXHancock33 min
Aug 19, 3:44 PM CDTSpecial Weather StatementLIXAmite, Wilkinson46 min
Aug 19, 3:55 PM CDTSevere Thunderstorm WarningLIXAmite, Pike35 min
Aug 19, 4:28 PM CDTSpecial Weather StatementLIXAmite, Wilkinson47 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2017Every severe thunderstorm warning in 2017

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.