Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 19, NWS Shreveport, LA

March 17, 2021Angelina County, Sabine County, San Augustine County, Texas

NWS Shreveport, LA issued this severe thunderstorm warning at Mar 17, 2021, 11:42 AM CDT for Angelina County, Sabine County, San Augustine County, Texas. It was in force for 48 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, 11:42 AM CDT (16:42 UTC)
Expired: Mar 17, 2021, 12:30 PM CDT
In force: 48 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Angelina County, TX, Sabine County, TX, San Augustine County, TX

The radar

The Ft Polk radar (KPOE), 117 km from the middle of the area, began a volume at 16:46 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, 8:43 AM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 4.7 hours before the alert went out and 147 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.

823 
WUUS54 KSHV 171642
SVRSHV
TXC005-403-405-171730-
/O.NEW.KSHV.SV.W.0019.210317T1642Z-210317T1730Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Shreveport LA
1142 AM CDT Wed Mar 17 2021

The National Weather Service in Shreveport has issued a

* Severe Thunderstorm Warning for...
  Southeastern Angelina County in eastern Texas...
  Southern San Augustine County in eastern Texas...
  Western Sabine County in eastern Texas...

* Until 1230 PM CDT.

* At 1141 AM CDT, a severe thunderstorm was located 8 miles north of
  Rockland, moving northeast at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  Milam, Hemphill, Pineland, Rosevine, Zavalla, Broaddus, Bronson,
  McElroy, Yellowpine and Chinaquapin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3118 9449 3126 9436 3123 9433 3122 9433
      3123 9432 3124 9433 3128 9433 3152 9392
      3125 9370 3115 9392 3114 9404 3112 9404
      3111 9406 3105 9438
TIME...MOT...LOC 1641Z 235DEG 34KT 3112 9433 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

44

2 follow-up statements

938 
WWUS54 KSHV 171657
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
1157 AM CDT Wed Mar 17 2021

TXC005-171707-
/O.CAN.KSHV.SV.W.0019.000000T0000Z-210317T1730Z/
Angelina TX-
1157 AM CDT Wed Mar 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN ANGELINA COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has 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.

LAT...LON 3112 9416 3112 9418 3117 9422 3119 9425
      3118 9426 3120 9427 3123 9432 3128 9433
      3152 9392 3125 9370 3116 9390 3114 9404
      3112 9404 3111 9406 3110 9413
TIME...MOT...LOC 1657Z 235DEG 34KT 3121 9419 

$$

TXC403-405-171730-
/O.CON.KSHV.SV.W.0019.000000T0000Z-210317T1730Z/
San Augustine TX-Sabine TX-
1157 AM CDT Wed Mar 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 PM CDT
FOR SOUTHERN SAN AUGUSTINE AND WESTERN SABINE COUNTIES...

At 1157 AM CDT, a severe thunderstorm was located 11 miles north of
Ebenezer, moving northeast at 40 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
Milam, Hemphill, Pineland, Rosevine, Broaddus, Bronson, McElroy,
Yellowpine and Chinaquapin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3112 9416 3112 9418 3117 9422 3119 9425
      3118 9426 3120 9427 3123 9432 3128 9433
      3152 9392 3125 9370 3116 9390 3114 9404
      3112 9404 3111 9406 3110 9413
TIME...MOT...LOC 1657Z 235DEG 34KT 3121 9419 

TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
 
$$

44

610 
WWUS54 KSHV 171720
SVSSHV

Severe Weather Statement
National Weather Service Shreveport LA
1220 PM CDT Wed Mar 17 2021

TXC403-405-171730-
/O.EXP.KSHV.SV.W.0019.000000T0000Z-210317T1730Z/
San Augustine TX-Sabine TX-
1220 PM CDT Wed Mar 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN SAN AUGUSTINE AND
WESTERN SABINE COUNTIES WILL EXPIRE AT 1230 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds are still possible with this thunderstorm.

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

LAT...LON 3112 9416 3112 9418 3117 9422 3119 9425
      3118 9426 3120 9427 3123 9432 3128 9433
      3152 9392 3125 9370 3116 9390 3114 9404
      3112 9404 3111 9406 3110 9413
TIME...MOT...LOC 1720Z 235DEG 34KT 3132 9401 

$$

44

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, 8:27 AM CDT	Severe Thunderstorm Warning	SHV	Angelina, Cherokee, Nacogdoches, Rusk, Shelby	63 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

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.