Alert archive / Texas / Severe Thunderstorm Watches in 2021

Severe Thunderstorm Watch 220

May 28, 202126 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at May 28, 2021, 3:41 PM CDT for 26 counties in Texas. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued: May 28, 2021, 3:41 PM CDT (20:41 UTC)
Expired: May 29, 2021, 12:00 AM CDT
In force: 8 hr
Issued by: the Storm Prediction Center
Largest hail expected: 3 in
Strongest gust expected: 60 kt

All 26 counties

Andrews County, TX, Brown County, TX, Coke County, TX, Coleman County, TX, Concho County, TX, Crane County, TX, Crockett County, TX, Ector County, TX, Edwards County, TX, Glasscock County, TX, Irion County, TX, Kimble County, TX, Martin County, TX, Mason County, TX, McCulloch County, TX, Menard County, TX, Midland County, TX, Reagan County, TX, Runnels County, TX, San Saba County, TX, Schleicher County, TX, Sterling County, TX, Sutton County, TX, Tom Green County, TX, Upton County, TX, Val Verde County, TX

The radar

The San Angelo radar (KSJT), 87 km from the middle of the area, began a volume at 20:45 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: 10%
Ten or more severe wind reports: 60%
One or more gusts of 65 knots or more: 20%
Ten or more severe hail reports: 90%
One or more hailstones of 2 inches or more: 80%
Six or more combined severe hail and wind reports: 95%

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
May 28, 4:03 PM CDT	Severe Thunderstorm Warning	SJT	Concho, Menard, Schleicher, Tom Green	42 min
May 28, 4:07 PM CDT	Severe Thunderstorm Warning	SJT	San Saba	38 min
May 28, 4:39 PM CDT	Severe Thunderstorm Warning	SJT	Irion, Tom Green	51 min
May 28, 4:40 PM CDT	Severe Thunderstorm Warning	SJT	Concho, Menard	65 min
May 28, 4:45 PM CDT	Severe Thunderstorm Warning	SJT	San Saba	22 min
May 28, 4:58 PM CDT	Severe Thunderstorm Warning	SJT	Coleman, Concho, Runnels	47 min
May 28, 5:09 PM CDT	Severe Thunderstorm Warning	SJT	Kimble, Menard, Schleicher, Sutton	51 min
May 28, 5:35 PM CDT	Severe Thunderstorm Warning	SJT	Irion, Tom Green	40 min
May 28, 5:35 PM CDT	Severe Thunderstorm Warning	SJT	Kimble, Menard	55 min
May 28, 5:46 PM CDT	Severe Thunderstorm Warning	MAF	Crane, Pecos, Reeves, Upton, Ward	59 min
May 28, 6:05 PM CDT	Severe Thunderstorm Warning	SJT	Kimble, Menard, Schleicher, Sutton	25 min
May 28, 6:12 PM CDT	Severe Thunderstorm Warning	SJT	Kimble	63 min
May 28, 6:32 PM CDT	Flash Flood Warning	SJT	Kimble	2 hr
May 28, 6:41 PM CDT	Severe Thunderstorm Warning	MAF	Crane, Ector, Midland, Upton, Ward, Winkler	64 min
May 28, 7:03 PM CDT	Severe Thunderstorm Warning	EWX	Edwards, Kerr, Real	57 min
May 28, 7:06 PM CDT	Severe Thunderstorm Warning	SJT	Kimble	54 min
May 28, 7:17 PM CDT	Severe Thunderstorm Warning	MAF	Crane, Midland, Upton	58 min
May 28, 7:39 PM CDT	Severe Thunderstorm Warning	MAF	Crane, Pecos, Upton	51 min
May 28, 7:43 PM CDT	Severe Thunderstorm Warning	MAF	Crane, Ector, Glasscock, Midland, Upton	62 min
May 28, 7:49 PM CDT	Severe Thunderstorm Warning	EWX	Bandera, Edwards, Gillespie, Kerr, Real	56 min
May 28, 9:50 PM CDT	Severe Thunderstorm Warning	MAF	Andrews, Dawson, Gaines, Martin	55 min
May 28, 10:40 PM CDT	Severe Thunderstorm Warning	MAF	Andrews, Culberson, Loving, Reeves, Ward, Winkler	65 min
May 28, 10:45 PM CDT	Severe Thunderstorm Warning	MAF	Andrews, Borden, Dawson, Ector, Gaines, Glasscock and 4 more	60 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

Midland Regional, TX (KMAF), launched 12:00Z, 8.7 hours before the alert went out and 96 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: 1694 J/kg
Mixed-layer CIN: -279 J/kg
Mixed-layer LCL: 1059 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 171 m²/s²
0-3 km storm-relative helicity: 164 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

The text

As transmitted.

136 
WWUS20 KWNS 282039
SEL0  
SPC WW 282039
TXZ000-290400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 220
NWS Storm Prediction Center Norman OK
340 PM CDT Fri May 28 2021

The NWS Storm Prediction Center has issued a

* Severe Thunderstorm Watch for portions of 
  West Central and Southwest Texas

* Effective this Friday afternoon and evening from 340 PM until
  1100 PM CDT.

* Primary threats include...
  Widespread large hail and scattered very large hail events to 3
    inches in diameter likely
  Scattered damaging wind gusts to 70 mph likely
  A tornado or two possible

SUMMARY...Isolated supercell thunderstorms are expected to develop
this afternoon in a very warm/humid and unstable air mass.  Storms
will pose a risk of very large hail and damaging wind gusts through
the evening.  A tornado or two is also possible.

The severe thunderstorm watch area is approximately along and 65
statute miles north and south of a line from 55 miles southwest of
Midland TX to 45 miles northeast of Junction TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU0).

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 218...WW 219...

AVIATION...A few severe thunderstorms with hail surface and aloft to
3 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 600. Mean storm motion vector
29025.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 27, 10:24 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Clay, Haskell, Jack, Knox and 7 more	96 min
May 28, 2:33 AM CDT	Mesoscale Discussion	SPC	Collin, Denton, Hunt, Rockwall, Wise	117 min
May 28, 5:10 AM CDT	Mesoscale Discussion	SPC	Briscoe, Castro, Childress, Cottle, Floyd, Foard and 7 more	2 hr
May 28, 11:16 AM CDT	Mesoscale Discussion	SPC	Bell, Bosque, Brazos, Brown, Burleson, Coleman and 19 more	89 min
May 28, 12:14 PM CDT	Severe Thunderstorm Watch	SPC	Bell, Bosque, Brazos, Burleson, Burnet, Comanche and 22 more	7 hr
May 28, 12:49 PM CDT	Mesoscale Discussion	SPC	Brewster, Pecos, Presidio, Terrell	86 min
May 28, 1:03 PM CDT	Mesoscale Discussion	SPC	Andrews, Bailey, Borden, Cochran, Dawson, Ector and 11 more	57 min
May 28, 2:33 PM CDT	Mesoscale Discussion	SPC	Andrews, Borden, Brown, Coke, Coleman, Concho and 35 more	117 min
May 28, 2:45 PM CDT	Severe Thunderstorm Watch	SPC	Brewster, Culberson, Jeff Davis, Loving, Pecos, Reeves and 3 more	9 hr
May 28, 3:42 PM CDT	Mesoscale Discussion	SPC	Bell, Brazos, Brown, Burleson, Burnet, Comanche and 12 more	93 min
May 28, 5:54 PM CDT	Mesoscale Discussion	SPC	Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 29 more	96 min
May 28, 6:20 PM CDT	Severe Thunderstorm Watch	SPC	Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 32 more	5 hr
May 28, 6:49 PM CDT	Mesoscale Discussion	SPC	Bailey, Deaf Smith, Parmer	86 min

Nearby

Severe Thunderstorm Watches in Texas, 2021 Every 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.