Alert archive / Texas / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 179

May 16, 202114 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at May 16, 2021, 7:08 PM CDT for 14 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 16, 2021, 7:08 PM CDT (00:08 UTC)
Expired
May 17, 2021, 1:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
65 kt

Counties Cottle County, TX, Crosby County, TX, Dickens County, TX, Floyd County, TX, Garza County, TX, Hale County, TX, Hockley County, TX, Kent County, TX, King County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Motley County, TX, Stonewall County, TX

The radar

The Lubbock radar (KLBB), 48 km from the middle of the area, began a volume at 00:10 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
10%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 16, 7:17 PM CDTSevere Thunderstorm WarningLUBCastro, Lamb43 min
May 16, 7:29 PM CDTSevere Thunderstorm WarningLUBCottle46 min
May 16, 7:42 PM CDTTornado Warning Tornado observedLUBLamb33 min
May 16, 8:13 PM CDTTornado WarningLUBLamb32 min
May 16, 8:44 PM CDTSevere Thunderstorm WarningLUBHale, Lamb46 min
May 16, 8:48 PM CDTSevere Thunderstorm WarningLUBBriscoe, Floyd, Hall, Motley57 min
May 16, 9:29 PM CDTSevere Thunderstorm WarningLUBHale, Lamb18 min
May 16, 9:40 PM CDTSevere Thunderstorm WarningLUBBriscoe, Childress, Cottle, Floyd, Hall, Motley65 min
May 16, 10:15 PM CDTSevere Thunderstorm WarningLUBHale45 min
May 16, 10:17 PM CDTSevere Thunderstorm WarningLUBKent, King, Stonewall58 min
May 16, 10:22 PM CDTSevere Thunderstorm WarningLUBFloyd, Motley23 min
May 16, 10:39 PM CDTSevere Thunderstorm WarningLUBChildress, Cottle, Crosby, Dickens, Floyd, King and 1 more66 min
May 16, 10:59 PM CDTSevere Thunderstorm WarningLUBCrosby, Floyd, Hale, Lubbock46 min
May 16, 11:42 PM CDTSevere Thunderstorm WarningLUBCrosby, Dickens, Floyd, King, Motley63 min
May 17, 12:40 AM CDTSevere Thunderstorm WarningLUBCrosby, Dickens, Floyd, King, Motley65 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

Amarillo Airport, TX (KAMA), launched 00:00Z, 0.1 hours before the alert went out and 151 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, Amarillo Airport, TX at 00:00Z on 2021-05-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 449 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, Amarillo Airport, TX at 00:00Z on 2021-05-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 square meters per square second.193958Sfc1 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
449 J/kg
Mixed-layer CIN
-105 J/kg
Mixed-layer LCL
2191 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
250 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.5

Open this sounding in Storm Lab

The text

As transmitted.

043 
WWUS20 KWNS 170004
SEL9  
SPC WW 170004
TXZ000-170400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 179
NWS Storm Prediction Center Norman OK
710 PM CDT Sun May 16 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  Northwest Texas

* Effective this Sunday evening from 710 PM until 1100 PM CDT.

* Primary threats include...
  Isolated significant damaging wind gusts to 75 mph possible
  Isolated very large hail events to 2 inches in diameter possible

SUMMARY...A couple slow-moving supercells should spread southeast
with large hail as the primary hazard and may congeal into a small
cluster with severe wind possible as well.

The severe thunderstorm watch area is approximately along and 45
statute miles north and south of a line from 30 miles west northwest
of Lubbock TX to 105 miles east of Lubbock TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU9).

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 177...WW 178...

AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
32020.

...Grams

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 16, 8:54 PM CDTMesoscale DiscussionSPCBriscoe, Cottle, Foard, Hall, King, Knox and 1 more96 min
May 16, 9:38 PM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Clay, Foard, Hardeman, Haskell and 10 more4 hr
May 16, 10:46 PM CDTMesoscale DiscussionSPCBaylor, Cottle, Dickens, Foard, Haskell, King and 3 more59 min
May 17, 1:09 AM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Crosby, Dickens, Fisher and 17 more96 min
May 17, 9:18 AM CDTMesoscale DiscussionSPCJasper, Jefferson, Newton, Orange117 min
May 17, 12:47 PM CDTMesoscale DiscussionSPCAustin, Bastrop, Bell, Blanco, Brazoria, Brazos and 29 more88 min
May 17, 1:39 PM CDTMesoscale DiscussionSPCDallam, Hartley, Oldham2 hr
May 17, 2:11 PM CDTMesoscale DiscussionSPCAndrews, Bailey, Borden, Castro, Cochran, Crane and 20 more2 hr
May 17, 2:39 PM CDTSevere Thunderstorm WatchSPCArmstrong, Carson, Collingsworth, Dallam, Donley, Gray and 10 more8 hr
May 17, 3:04 PM CDTTornado WatchSPCAndrews, Bailey, Borden, Briscoe, Castro, Cochran and 39 more8 hr
May 17, 4:44 PM CDTTornado WatchSPCBaylor, Childress, Cottle, Fisher, Foard, Hardeman and 10 more6 hr
May 17, 4:53 PM CDTMesoscale DiscussionSPCBaylor, Callahan, Childress, Cottle, Fisher, Foard and 11 more97 min
May 17, 5:10 PM CDTMesoscale DiscussionSPCDallam, Hansford, Hartley, Hutchinson, Moore, Ochiltree and 3 more2 hr
May 17, 5:36 PM CDTMesoscale DiscussionSPCAndrews, Armstrong, Bailey, Borden, Briscoe, Castro and 38 more84 min
May 17, 6:13 PM CDTMesoscale DiscussionSPCDimmit, La Salle, Webb92 min
May 17, 6:40 PM CDTSevere Thunderstorm WatchSPCDimmit, Frio, La Salle, Maverick, Webb, Zavala4 hr

Nearby

Severe Thunderstorm Watches in Texas, 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.