Alert archive / Texas / Special Weather Statements in 2021

Special Weather Statement, NWS Shreveport, LA

April 30, 2021Shelby County, Texas

NWS Shreveport, LA issued this special weather statement at Apr 30, 2021, 12:39 AM CDT for Shelby County, Texas. It was in force for 51 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
Apr 30, 2021, 12:39 AM CDT (05:39 UTC)
Expired
Apr 30, 2021, 1:30 AM CDT
In force
51 min
Issued by
NWS Shreveport, LA

County Shelby County, TX

The radar

The Shreveport radar (KSHV), 100 km from the middle of the area, began a volume at 05:42 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 5.7 hours before the alert went out and 181 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, Lake Charles Mun, LA at 00:00Z on 2021-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1081 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, Lake Charles Mun, LA at 00:00Z on 2021-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 square meters per square second.19395878Sfc1 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
1081 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
811 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7

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 Shreveport, LA wrote its last area forecast discussion before this special weather statement went out at Apr 29, 10:19 PM CDT, 2 hours 20 minutes earlier.

Area forecast discussion, Apr 29, 10:19 PM CDT, 2 hours 20 minutes 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.
      </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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Hazardous weather outlook, Apr 29, 1:48 PM CDT, 10 hours 51 minutes before
Hazardous Weather Outlook
National Weather Service Shreveport LA
148 PM CDT Thu Apr 29 2021

ARZ050-051-059>061-070>073-OKZ077-TXZ096-097-301900-
Sevier-Howard-Little River-Hempstead-Nevada-Miller-Lafayette-
Columbia-Union-McCurtain-Red River-Bowie-
148 PM CDT Thu Apr 29 2021

This Hazardous Weather Outlook is for portions of south central
Arkansas, southwest Arkansas, southeast Oklahoma and northeast
Texas.

.DAY ONE...This Afternoon and Tonight...

Showers and perhaps a few thunderstorms will be possible this
afternoon. While a few of the storms may be strong at times,
widespread severe weather is not anticipated at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday...

Some slightly cooler and drier air will filter into the area in
wake of the front on Friday, but rain chances will continue
through the weekend, as an upper level trough moves across the
region. Dry weather will return on Monday, but rain chances return
by the middle of next week, as another cool front moves into the
region.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel...amateur radio
operators...and storm spotters may be needed through Thursday.
Please relay any information about observed severe weather to the
NWS while following all local, state, and CDC guidelines.

LAZ001>006-010>014-017>022-TXZ108>112-124>126-136>138-149>153-
165>167-301900-
Caddo-Bossier-Webster-Claiborne-Lincoln-Union-De Soto-Red River-
Bienville-Jackson-Ouachita-Sabine-Natchitoches-Winn-Grant-
Caldwell-La Salle-Franklin-Titus-Camp-Morris-Cass-Wood-Upshur-
Marion-Smith-Gregg-Harrison-Cherokee-Rusk-Panola-Nacogdoches-
Shelby-Angelina-San Augustine-
148 PM CDT Thu Apr 29 2021

This Hazardous Weather Outlook is for portions of north central
Louisiana, northwest Louisiana, east Texas and northeast Texas.

.DAY ONE...This Afternoon and Tonight...

Showers and thunderstorms are expected in increase this afternoon.
Strong to marginally severe thunderstorms capable of producing
some large hail, strong wind gusts, and perhaps a tornado or two
will be possible but not highly anticipated and not expected to be
widespread. In addition, there is also a potential for heavy
rainfall from training showers and thunderstorms that will bring a
potential for some localized flash flooding.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday...

Some slightly cooler and drier air will filter into the area in
wake of the front on Friday, but rain chances will continue
through the weekend, as an upper level trough moves across the
region. Dry weather will return on Monday, but rain chances return
by the middle of next week, as another cool front moves into the
region.

.SPOTTER INFORMATION STATEMENT...

Activation of emergency management personnel...amateur radio
operators...and storm spotters may be needed this afternoon and
tonight. Please relay any information about observed severe
weather to the NWS while following all local, state, and CDC
guidelines.

In the hours before

Special weather statement, Apr 29, 11:15 PM CDT, 1 hour 24 minutes before
Special Weather Statement
National Weather Service Shreveport LA
1115 PM CDT Thu Apr 29 2021

TXZ152-153-166-300500-
Nacogdoches TX-San Augustine TX-Shelby TX-
1115 PM CDT Thu Apr 29 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN NACOGDOCHES...SHELBY
AND NORTHWESTERN SAN AUGUSTINE COUNTIES UNTIL MIDNIGHT CDT...

At 1115 PM CDT, Doppler radar was tracking a strong thunderstorm over
Martinsville, or 11 miles east of Nacogdoches, moving northeast at 45
mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Center, Joaquin, Melrose, Patroon, Shelbyville, Martinsville, Bland
Lake, Neuville, Appleby, Chireno, Hurstown, James, Jericho, Calgary,
Stockman, Arcadia and Jordans Store.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3146 9450 3171 9464 3197 9405 3164 9386
TIME...MOT...LOC 0415Z 245DEG 39KT 3164 9445

44
Special weather statement, Apr 30, 12:04 AM CDT, 35 minutes before
Special Weather Statement
National Weather Service Shreveport LA
1204 AM CDT Fri Apr 30 2021

LAZ010-017-TXZ153-300545-
De Soto LA-Sabine LA-Shelby TX-
1204 AM CDT Fri Apr 30 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL DE SOTO...
NORTHWESTERN SABINE PARISHES IN NORTHWESTERN LOUISIANA AND EASTERN
SHELBY COUNTIES UNTIL 1245 AM CDT...

At 1204 AM CDT, Doppler radar was tracking a strong thunderstorm near
Shelbyville, or 9 miles southeast of Center, moving east at 45 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Center, Converse, Patroon, Shelbyville, Oak Grove, Pleasant Hill,
Huxley, Noble, Hurstown, James, Belmont, Pelican, Toledo Bend
Reservoir North and Jordans Store.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3162 9409 3162 9411 3183 9420 3199 9358
      3168 9348 3159 9403
TIME...MOT...LOC 0504Z 254DEG 40KT 3171 9404

44
Special weather statement, Apr 30, 12:39 AM CDT, 0 minutes before
Special Weather Statement
National Weather Service Shreveport LA
1239 AM CDT Fri Apr 30 2021

LAZ017-TXZ153-166-167-300630-
Sabine LA-Sabine TX-San Augustine TX-Shelby TX-
1239 AM CDT Fri Apr 30 2021

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN SABINE PARISH...
SOUTHEASTERN SHELBY...NORTHEASTERN SAN AUGUSTINE AND NORTHWESTERN
SABINE COUNTIES UNTIL 130 AM CDT...

At 1238 AM CDT, Doppler radar was tracking a strong thunderstorm near
Bland Lake, or 15 miles south of Center, moving east at 40 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Milam, San Augustine, Bland Lake, Neuville, Patroon, Huxley,
Hurstown, Denning, Sexton, Calgary, Toledo Bend Reservoir North and
Jordans Store.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3146 9427 3167 9431 3177 9375 3149 9369
TIME...MOT...LOC 0538Z 260DEG 36KT 3157 9420

44

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 11:15 PM CDTSpecial Weather StatementSHVShelby45 min
Apr 30, 12:04 AM CDTSpecial Weather StatementSHVShelby41 min
Apr 30, 1:24 AM CDTSpecial Weather StatementSHVSabine51 min
Apr 30, 3:28 AM CDTAreal Flood AdvisorySHVAngelina, Cherokee, Nacogdoches, Sabine, San Augustine, Shelby3 hr
Apr 30, 4:11 AM CDTFlash Flood WarningSHVAngelina, Cherokee, Nacogdoches, San Augustine, Shelby3 hr
Apr 30, 5:10 AM CDTRiver Flood WarningSHVNacogdoches, Rusk, San Augustine, Shelby46 days
Apr 30, 5:12 AM CDTRiver Flood WarningSHVSabine, San Augustine40 hr
Apr 30, 5:14 AM CDTRiver Flood WarningSHVAngelina, Houston, Polk, Trinity, Tyler51 days
Apr 30, 6:22 AM CDTAreal Flood AdvisorySHVAngelina, Nacogdoches, Sabine, San Augustine113 min
Apr 30, 7:18 AM CDTRiver Flood WarningSHVAnderson, Cherokee, Houston, Trinity13 hr
Apr 30, 9:39 AM CDTRiver Flood WarningSHVBowie, Red River25 hr
Apr 30, 2:10 AM CDTSpecial Weather StatementSHVNatchitoches50 min

Nearby

Special Weather Statements in Texas, 2021Every 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; radar from the NEXRAD Level II archive.