Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 12, NWS Shreveport, LA

March 17, 20218 counties in Texas

NWS Shreveport, LA issued this severe thunderstorm warning at Mar 17, 2021, 7:32 AM CDT for 8 counties in Texas. It was in force for 58 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Mar 17, 2021, 7:32 AM CDT (12:32 UTC)
Expired: Mar 17, 2021, 8:30 AM CDT
In force: 58 min
Issued by: NWS Shreveport, LA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

Counties Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Panola County, TX, Rusk County, TX, Smith County, TX, Upshur County, TX

The radar

The Shreveport radar (KSHV), 78 km from the middle of the area, began a volume at 12:31 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.

What was reported inside it

Time	Report	Where	Remark
Mar 17, 7:52 AM CDT	TSTM WND DMG	1 Wnw Arp, TX	MULTIPLE TREES REPORTED DOWN IN THE SOUTH EAST PART OF THE COUNTY.
Mar 17, 8:20 AM CDT	HAIL 0.7	Henderson, TX	PEA TO DIME SIZE HAIL IN HENDERSON.
Mar 17, 8:31 AM CDT	HAIL 0.5	1 Nne Hallsville, TX	REPORT FROM MPING: HALF-INCH (0.50 IN.).
Mar 17, 8:38 AM CDT	TSTM WND DMG	10 Nw Nesbitt, TX	TREES REPORTED DOWN.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

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, 0.5 hours before the alert went out and 87 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.

021 
WUUS54 KSHV 171232
SVRSHV
TXC073-183-203-315-365-401-423-459-171330-
/O.NEW.KSHV.SV.W.0012.210317T1232Z-210317T1330Z/

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

The National Weather Service in Shreveport has issued a

* Severe Thunderstorm Warning for...
  Southeastern Smith County in northeastern Texas...
  Central Marion County in northeastern Texas...
  Harrison County in northeastern Texas...
  Northwestern Panola County in northeastern Texas...
  Northern Rusk County in northeastern Texas...
  Southern Upshur County in northeastern Texas...
  Gregg County in northeastern Texas...
  Northwestern Cherokee County in northeastern Texas...

* Until 830 AM CDT.

* At 731 AM CDT, severe thunderstorms were located along a line
  extending from near Gladewater to near Liberty City to Arp to near
  Mixon, moving east 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...
  Longview, Marshall, Henderson, Kilgore, Whitehouse, White Oak,
  Gladewater, Hallsville, Overton, Bullard, Jefferson, Troup, Tatum,
  Big Sandy, New London, Arp, Clarksville City, Beckville, East
  Mountain and Berea.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3288 9418 3263 9416 3242 9422 3215 9445
      3205 9539 3225 9524 3245 9517 3266 9510
TIME...MOT...LOC 1231Z 255DEG 36KT 3256 9502 3245 9501 3224 9507 3202
9522

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

09

2 follow-up statements

975 
WWUS54 KSHV 171300
SVSSHV

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

TXC073-183-203-315-365-401-423-459-171330-
/O.CON.KSHV.SV.W.0012.000000T0000Z-210317T1330Z/
Smith TX-Marion TX-Harrison TX-Panola TX-Rusk TX-Upshur TX-Gregg TX-
Cherokee TX-
800 AM CDT Wed Mar 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 AM CDT
FOR SOUTHEASTERN SMITH...CENTRAL MARION...HARRISON...NORTHWESTERN
PANOLA...NORTHERN RUSK...SOUTHEASTERN UPSHUR...GREGG AND NORTH
CENTRAL CHEROKEE COUNTIES...

At 800 AM CDT, severe thunderstorms were located along a line
extending from near Diana to near Longview to 7 miles southeast of
Kilgore to near Turnertown, moving east 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...
Longview, Marshall, Henderson, Kilgore, Whitehouse, White Oak,
Gladewater, Hallsville, Overton, Jefferson, Troup, Tatum, New London,
Arp, Clarksville City, Beckville, East Mountain, Berea, Harleton and
Diana.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3288 9418 3263 9416 3242 9422 3215 9445
      3206 9528 3224 9519 3244 9504 3270 9494
TIME...MOT...LOC 1300Z 252DEG 36KT 3264 9472 3253 9471 3232 9477 3210
9492

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

09

038 
WWUS54 KSHV 171319
SVSSHV

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

TXC073-423-459-171329-
/O.CAN.KSHV.SV.W.0012.000000T0000Z-210317T1330Z/
Smith TX-Upshur TX-Cherokee TX-
819 AM CDT Wed Mar 17 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SMITH...
SOUTHEASTERN UPSHUR AND NORTH CENTRAL CHEROKEE COUNTIES IS
CANCELLED...

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

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

LAT...LON 3288 9418 3263 9416 3242 9422 3215 9445
      3209 9497 3224 9493 3242 9488 3259 9472
      3277 9464
TIME...MOT...LOC 1319Z 253DEG 35KT 3269 9454 3258 9453 3237 9460 3215
9475

$$

TXC183-203-315-365-401-171330-
/O.CON.KSHV.SV.W.0012.000000T0000Z-210317T1330Z/
Marion TX-Harrison TX-Panola TX-Rusk TX-Gregg TX-
819 AM CDT Wed Mar 17 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 AM CDT
FOR CENTRAL MARION...HARRISON...NORTHWESTERN PANOLA...NORTHERN RUSK
AND EASTERN GREGG COUNTIES...

At 819 AM CDT, severe thunderstorms were located along a line
extending from near Harleton to 6 miles northeast of Hallsville to 6
miles northwest of Tatum to near Henderson, moving east 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...
Longview, Marshall, Henderson, Kilgore, Hallsville, Jefferson, Tatum,
New London, Beckville, Berea, Harleton, Karnack, Woodlawn,
Joinerville, Lakeport, Easton, Scottsville, Nesbitt, Rolling Meadows
and Darco.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3288 9418 3263 9416 3242 9422 3215 9445
      3209 9497 3224 9493 3242 9488 3259 9472
      3277 9464
TIME...MOT...LOC 1319Z 253DEG 35KT 3269 9454 3258 9453 3237 9460 3215
9475

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, 7:36 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
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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.