Alert archive / Texas / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 14
The Storm Prediction Center issued this severe thunderstorm watch at Feb 28, 2021, 5:54 PM CST for 6 counties in Arkansas; 9 parishes in Louisiana; 12 counties in Texas. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Feb 28, 2021, 5:54 PM CST (23:54 UTC)
- Expired
- Feb 28, 2021, 10:00 PM CST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 55 kt
All 27 counties
Columbia County, AR, Hempstead County, AR, Lafayette County, AR, Miller County, AR, Nevada County, AR, Union County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Lincoln Parish, LA, Red River Parish, LA, Union Parish, LA, Webster Parish, LA, Bowie County, TX, Cass County, TX, Cherokee County, TX, Gregg County, TX, Harrison County, TX, Marion County, TX, Nacogdoches County, TX, Panola County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Upshur County, TX
The radar
The Shreveport radar (KSHV), 28 km from the middle of the area, began a volume at 23:54 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 6:07 PM CST | Tornado Warning | SHV | Lafayette, Miller | 38 min |
| Feb 28, 6:44 PM CST | Severe Thunderstorm Warning | SHV | Lafayette, Miller | 31 min |
| Feb 28, 8:08 PM CST | Tornado Warning | SHV | Bossier, Caddo, Webster | 52 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Shreveport, LA (KSHV), launched 12:00Z, 11.9 hours before the alert went out and 19 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.
- Mixed-layer CAPE
- 458 J/kg
- Mixed-layer CIN
- -126 J/kg
- Mixed-layer LCL
- 573 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 321 m²/s²
- 0-3 km storm-relative helicity
- 414 m²/s²
- Significant tornado parameter
- 0.4
- Supercell composite
- 1.2
The text
As transmitted.
582 WWUS20 KWNS 282350 SEL4 SPC WW 282350 ARZ000-LAZ000-TXZ000-010400- URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 14 NWS Storm Prediction Center Norman OK 550 PM CST Sun Feb 28 2021 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southwest Arkansas Northwest Louisiana Northeast Texas * Effective this Sunday afternoon and evening from 550 PM until 1000 PM CST. * Primary threats include... Isolated damaging wind gusts to 65 mph possible Isolated large hail events to 1.5 inches in diameter possible A tornado or two possible SUMMARY...Multiple discrete cells should persist along a cold front that will shift southeast this evening, and may consolidate into a cluster across the Arklatex region. Large hail and damaging winds should be the primary threats. The severe thunderstorm watch area is approximately along and 50 statute miles north and south of a line from 15 miles east of El Dorado AR to 35 miles southwest of Longview TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 12...WW 13... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 23030. ...Grams
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 28, 9:59 AM CST | Mesoscale Discussion | SPC | Howard, Polk, Sevier | 91 min |
| Feb 28, 10:43 AM CST | Severe Thunderstorm Watch | SPC | Hempstead, Howard, Lafayette, Little River, Miller, Montgomery and 5 more | 7 hr |
| Feb 28, 1:01 PM CST | Mesoscale Discussion | SPC | Arkansas, Clark, Clay, Cleburne, Cleveland, Conway and 32 more | 119 min |
| Feb 28, 2:22 PM CST | Tornado Watch | SPC | Arkansas, Bradley, Calhoun, Clark, Clay, Cleburne and 32 more | 8 hr |
| Feb 28, 2:25 PM CST | Mesoscale Discussion | SPC | Hempstead, Howard, Little River, Miller, Pike, Sevier | 2 hr |
| Feb 28, 4:40 PM CST | Mesoscale Discussion | SPC | Arkansas, Bradley, Calhoun, Clark, Cleveland, Craighead and 23 more | 95 min |
| Feb 28, 5:28 PM CST | Mesoscale Discussion | SPC | Hempstead, Howard, Lafayette, Little River, Miller, Nevada and 2 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Texas, 2021Severe Thunderstorm Watches in Louisiana, 2021Severe Thunderstorm Watches in Arkansas, 2021Every severe thunderstorm watch 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.