Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 15, NWS Shreveport, LA

March 17, 20215 counties in Texas

NWS Shreveport, LA issued this severe thunderstorm warning at Mar 17, 2021, 8:27 AM CDT for 5 counties in Texas. It was in force for 63 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: Mar 17, 2021, 8:27 AM CDT (13:27 UTC)
Expired: Mar 17, 2021, 9:30 AM CDT
In force: 63 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

Counties Angelina County, TX, Cherokee County, TX, Nacogdoches County, TX, Rusk County, TX, Shelby County, TX

The radar

The Shreveport radar (KSHV), 148 km from the middle of the area, began a volume at 13:31 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Mar 17, 4:37 AM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 1.5 hours before the alert went out and 156 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: 1417 J/kg
Mixed-layer CIN: -55 J/kg
Mixed-layer LCL: 682 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 328 m²/s²
0-3 km storm-relative helicity: 340 m²/s²
Significant tornado parameter: 2.7
Supercell composite: 14.5

Open this sounding in Storm Lab

The text

As transmitted.

610 
WUUS54 KSHV 171327
SVRSHV
TXC005-073-347-401-419-171430-
/O.NEW.KSHV.SV.W.0015.210317T1327Z-210317T1430Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Shreveport LA
827 AM CDT Wed Mar 17 2021

The National Weather Service in Shreveport has issued a

* Severe Thunderstorm Warning for...
  Southeastern Rusk County in northeastern Texas...
  Nacogdoches County in eastern Texas...
  Northwestern Shelby County in eastern Texas...
  Northwestern Angelina County in eastern Texas...
  Southeastern Cherokee County in northeastern Texas...

* Until 930 AM CDT.

* At 826 AM CDT, severe thunderstorms were located along a line
  extending from near Sacul to near Forest to Kennard, moving east at
  35 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings.

* Locations impacted include...
  Lufkin, Nacogdoches, Hudson, Alto, Timpson, Garrison, Wells,
  Morrill, Melrose, Woden, Pollok, Sacul, Forest, Douglass, Trawick,
  Cushing, Appleby, Stockman, Clawson and Central.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3138 9495 3142 9500 3144 9500 3145 9505
      3147 9506 3147 9510 3149 9511 3150 9509
      3152 9510 3154 9514 3156 9514 3158 9517
      3180 9512 3196 9428 3165 9441 3139 9459
      3134 9496
TIME...MOT...LOC 1326Z 251DEG 29KT 3176 9497 3147 9504 3138 9516 

HAIL...1.00IN
WIND...70MPH
 
$$

09

2 follow-up statements

464 
WWUS54 KSHV 171345
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
845 AM CDT Wed Mar 17 2021

TXC005-073-347-401-419-171430-
/O.CON.KSHV.SV.W.0015.000000T0000Z-210317T1430Z/
Rusk TX-Nacogdoches TX-Shelby TX-Angelina TX-Cherokee TX-
845 AM CDT Wed Mar 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 AM CDT
FOR SOUTHEASTERN RUSK...NACOGDOCHES...NORTHWESTERN SHELBY...
NORTHWESTERN ANGELINA AND SOUTHEASTERN CHEROKEE COUNTIES...

At 844 AM CDT, severe thunderstorms were located along a line
extending from near Trawick to 7 miles southeast of Douglass to near
Wells, moving northeast at 40 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Nacogdoches, Timpson, Garrison, Wells, Melrose, Woden, Pollok, Sacul,
Forest, Douglass, Trawick, Cushing, Appleby, Stockman, Central,
Linwood, Lilbert and Looneyville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 100 PM CDT for eastern Texas.

A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted act quickly and move to a place
of safety inside a sturdy structure, such as a basement or small
interior room.

&&

LAT...LON 3147 9453 3139 9497 3142 9500 3144 9500
      3145 9505 3147 9506 3164 9500 3183 9494
      3196 9428 3165 9441
TIME...MOT...LOC 1344Z 246DEG 34KT 3181 9482 3157 9482 3143 9501 

HAIL...1.00IN
WIND...70MPH
 
$$

09

384 
WWUS54 KSHV 171404
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
904 AM CDT Wed Mar 17 2021

TXC073-171413-
/O.CAN.KSHV.SV.W.0015.000000T0000Z-210317T1430Z/
Cherokee TX-
904 AM CDT Wed Mar 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHEROKEE COUNTY
IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 100 PM CDT for eastern Texas.

A Severe Thunderstorm Watch remains in effect until 1000 AM CDT for
northeastern Texas.

LAT...LON 3140 9494 3151 9486 3166 9482 3186 9477
      3196 9428 3165 9441 3147 9453
TIME...MOT...LOC 1403Z 247DEG 26KT 3186 9454 3164 9467 3144 9479 

$$

TXC005-347-401-419-171430-
/O.CON.KSHV.SV.W.0015.000000T0000Z-210317T1430Z/
Rusk TX-Nacogdoches TX-Shelby TX-Angelina TX-
904 AM CDT Wed Mar 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 930 AM CDT
FOR SOUTHEASTERN RUSK...NORTHERN NACOGDOCHES...NORTHWESTERN SHELBY
AND NORTHWESTERN ANGELINA COUNTIES...

At 903 AM CDT, severe thunderstorms were located along a line
extending from near Garrison to Nacogdoches to near Pollok, moving
east at 30 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Nacogdoches, Timpson, Garrison, Melrose, Woden, Pollok, Trawick,
Appleby, Stockman and Central.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 100 PM CDT for eastern Texas.

A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted act quickly and move to a place
of safety inside a sturdy structure, such as a basement or small
interior room.

&&

LAT...LON 3140 9494 3151 9486 3166 9482 3186 9477
      3196 9428 3165 9441 3147 9453
TIME...MOT...LOC 1403Z 247DEG 26KT 3186 9454 3164 9467 3144 9479 

HAIL...1.00IN
WIND...70MPH
 
$$

09

The office that day

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

Issued	Product	Office	Counties	Lasted
Mar 17, 1:30 AM CDT	Special Weather Statement	SHV	Marion	45 min
Mar 17, 2:45 AM CDT	Lake Wind Advisory	SHV	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more	40 hr
Mar 17, 6:12 AM CDT	Severe Thunderstorm Warning	SHV	Camp, Franklin, Smith, Titus, Wood	63 min
Mar 17, 6:49 AM CDT	Special Weather Statement	SHV	Cherokee, Smith	41 min
Mar 17, 6:56 AM CDT	Severe Thunderstorm Warning	SHV	Bowie, Camp, Franklin, Morris, Red River, Titus	49 min
Mar 17, 7:08 AM CDT	Tornado Warning	SHV	Bowie, Cass, Morris, Red River, Titus	37 min
Mar 17, 7:12 AM CDT	Special Weather Statement	SHV	Camp, Gregg, Morris, Upshur	48 min
Mar 17, 7:32 AM CDT	Severe Thunderstorm Warning	SHV	Cherokee, Gregg, Harrison, Marion, Panola, Rusk and 2 more	58 min
Mar 17, 7:36 AM CDT	Severe Thunderstorm Warning	SHV	Bowie, Cass, Morris	54 min
Mar 17, 7:43 AM CDT	Severe Thunderstorm Warning	SHV	Cherokee, Nacogdoches, Panola, Rusk, Smith	62 min
Mar 17, 7:59 AM CDT	Special Weather Statement	SHV	Cass	31 min
Mar 17, 8:34 AM CDT	Severe Thunderstorm Warning	SHV	Cass, Gregg, Harrison, Marion, Panola, Rusk	56 min
Mar 17, 8:40 AM CDT	Severe Thunderstorm Warning	SHV	Nacogdoches, Panola, Rusk, Shelby	44 min
Mar 17, 9:29 AM CDT	Severe Thunderstorm Warning	SHV	Nacogdoches, Panola, Rusk, San Augustine, Shelby	61 min
Mar 17, 11:42 AM CDT	Severe Thunderstorm Warning	SHV	Angelina, Sabine, San Augustine	48 min

Nearby

Severe Thunderstorm Warnings in Texas, 2021 Every severe thunderstorm warning 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.