Alert archive / Texas / Tornado Watches in 2021

Tornado Watch 185

May 17, 202110 counties in Texas

The Storm Prediction Center issued this tornado watch at May 17, 2021, 7:32 PM CDT for 10 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 17, 2021, 7:32 PM CDT (00:32 UTC)
Expired
May 17, 2021, 11:00 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
80 kt

Counties Brown County, TX, Callahan County, TX, Coke County, TX, Coleman County, TX, Concho County, TX, McCulloch County, TX, Menard County, TX, Runnels County, TX, Schleicher County, TX, Tom Green County, TX

The radar

The San Angelo radar (KSJT), 56 km from the middle of the area, began a volume at 00:31 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
40%
One or more EF2 to EF5 tornadoes
40%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
50%
Ten or more severe hail reports
50%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 17, 8:42 PM CDTSevere Thunderstorm WarningSJTCoke, Sterling36 min
May 17, 9:11 PM CDTSevere Thunderstorm WarningSJTCoke, Nolan, Runnels, Taylor64 min
May 17, 9:24 PM CDTSevere Thunderstorm WarningSJTCallahan, Jones, Shackelford, Taylor51 min
May 17, 10:22 PM CDTSevere Thunderstorm WarningSJTCoke38 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 00:00Z, 0.5 hours before the alert went out and 205 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, Midland Regional, TX at 00:00Z on 2021-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 953 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Midland Regional, TX at 00:00Z on 2021-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 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
953 J/kg
Mixed-layer CIN
-44 J/kg
Mixed-layer LCL
1920 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

As transmitted.

779 
WWUS20 KWNS 180030
SEL5  
SPC WW 180030
TXZ000-180400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 185
NWS Storm Prediction Center Norman OK
735 PM CDT Mon May 17 2021

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  West-central Texas

* Effective this Monday evening from 735 PM until 1100 PM CDT.

* Primary threats include...
  A couple intense tornadoes possible
  Scattered damaging winds and isolated significant gusts to 90
    mph possible
  Scattered large hail and isolated very large hail events to 3
    inches in diameter possible

SUMMARY...Intense supercells within a broader cluster should spread
southeast across a portion of the Big Country and Concho Valley
region through late evening.

The tornado watch area is approximately along and 45 statute miles
north and south of a line from 15 miles west of San Angelo TX to 95
miles east northeast of San Angelo TX. For a complete depiction of
the watch see the associated watch outline update (WOUS64 KWNS
WOU5).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and 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.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 181...WW 182...WW
183...WW 184...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 3 inches. Extreme turbulence and surface wind
gusts to 80 knots. A few cumulonimbi with maximum tops to 600. Mean
storm motion vector 31020.

...Grams

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 17, 7:04 PM CDTMesoscale DiscussionSPCArcher, Bosque, Brown, Clay, Comanche, Eastland and 15 more86 min
May 17, 7:23 PM CDTMesoscale DiscussionSPCCarson, Dallam, Gray, Hansford, Hartley, Hemphill and 8 more2 hr
May 17, 7:37 PM CDTMesoscale DiscussionSPCCallahan, Coke, Coleman, Glasscock, Howard, Jones and 6 more83 min
May 17, 8:04 PM CDTSevere Thunderstorm WatchSPCArcher, Clay, Comanche, Eastland, Erath, Hamilton and 11 more5 hr
May 17, 8:34 PM CDTMesoscale DiscussionSPCAtascosa, Dimmit, Frio, La Salle, McMullen, Maverick and 2 more116 min
May 17, 9:28 PM CDTMesoscale DiscussionSPCCarson, Collingsworth, Donley, Gray, Hansford, Hemphill and 7 more2 hr
May 17, 9:44 PM CDTMesoscale DiscussionSPCArmstrong, Borden, Briscoe, Childress, Collingsworth, Cottle and 15 more91 min
May 17, 10:23 PM CDTMesoscale DiscussionSPCArcher, Brown, Callahan, Clay, Coke, Coleman and 16 more97 min
May 17, 10:35 PM CDTMesoscale DiscussionSPCAndrews, Borden, Brewster, Crane, Crockett, Dawson and 13 more85 min
May 17, 10:58 PM CDTSevere Thunderstorm WatchSPCAndrews, Borden, Brown, Coke, Coleman, Concho and 22 more7 hr
May 17, 11:37 PM CDTMesoscale DiscussionSPCBosque, Brown, Comanche, Denton, Eastland, Erath and 9 more83 min
May 18, 1:02 AM CDTMesoscale DiscussionSPCBrooks, Duval, Jim Hogg58 min
May 18, 1:29 AM CDTMesoscale DiscussionSPCCoke, Concho, Crane, Crockett, Ector, Glasscock and 13 more91 min
May 18, 5:07 AM CDTMesoscale DiscussionSPCCoke, Concho, Irion, Reagan, Runnels, Schleicher and 2 more53 min
May 18, 1:18 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bastrop, Bexar, Brazos, Burleson and 28 more117 min
May 18, 1:57 PM CDTMesoscale DiscussionSPCBailey, Castro, Deaf Smith, Parmer, Randall, Swisher3 hr
May 18, 2:29 PM CDTTornado WatchSPCAnderson, Atascosa, Austin, Bastrop, Bexar, Blanco and 30 more7 hr
May 18, 2:30 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Cherokee, Franklin, Gregg and 12 more2 hr
May 18, 3:51 PM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Cherokee, Franklin, Gregg and 11 more5 hr
May 18, 3:52 PM CDTMesoscale DiscussionSPCBastrop, Caldwell, Colorado, Fayette, Gonzales, Guadalupe and 2 more83 min
May 18, 5:10 PM CDTMesoscale DiscussionSPCLa Salle, McMullen, Webb95 min
May 18, 5:39 PM CDTMesoscale DiscussionSPCBowie, Cass, Gregg, Harrison, Marion, Morris and 1 more2 hr
May 18, 6:07 PM CDTMesoscale DiscussionSPCArmstrong, Borden, Briscoe, Carson, Castro, Cochran and 17 more113 min
May 18, 6:13 PM CDTMesoscale DiscussionSPCAustin, Brazos, Burleson, Colorado, DeWitt, Fayette and 14 more92 min

Nearby

Tornado Watches in Texas, 2021Every tornado 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.