Alert archive / Texas / Tornado Watches in 2021

Tornado Watch 100

April 23, 20218 counties in Oklahoma; 13 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 23, 2021, 3:14 PM CDT for 8 counties in Oklahoma; 13 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 23, 2021, 3:14 PM CDT (20:14 UTC)
Expired
Apr 23, 2021, 8:02 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
3.5 in
Strongest gust expected
60 kt
All 21 counties

Comanche County, OK, Cotton County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, Tillman County, OK, Archer County, TX, Baylor County, TX, Childress County, TX, Clay County, TX, Collingsworth County, TX, Cottle County, TX, Foard County, TX, Hardeman County, TX, King County, TX, Knox County, TX, Stonewall County, TX, Wichita County, TX, Wilbarger County, TX

The radar

The Altus AFB radar (KFDR), 35 km from the middle of the area, began a volume at 20:14 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
50%
One or more EF2 to EF5 tornadoes
20%
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
70%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 23, 3:51 PM CDTSevere Thunderstorm WarningLUBChildress, Cottle, Hall54 min
Apr 23, 4:10 PM CDTTornado WarningLUBChildress, Cottle35 min
Apr 23, 4:44 PM CDTSevere Thunderstorm WarningLUBChildress, Cottle31 min
Apr 23, 4:44 PM CDTSevere Thunderstorm WarningOUNFoard, Hardeman46 min
Apr 23, 5:17 PM CDTSevere Thunderstorm WarningOUNFoard, Knox43 min
Apr 23, 5:23 PM CDTSevere Thunderstorm WarningOUNBaylor, Knox52 min
Apr 23, 5:28 PM CDTSevere Thunderstorm WarningLUBChildress, Hall62 min
Apr 23, 5:28 PM CDTSevere Thunderstorm WarningOUNFoard, Hardeman47 min
Apr 23, 5:40 PM CDTTornado WarningOUNFoard, Hardeman39 min
Apr 23, 5:42 PM CDTTornado WarningLUBChildress, Cottle, Hall, Motley33 min
Apr 23, 5:52 PM CDTSevere Thunderstorm WarningOUNBaylor, Foard, Wilbarger38 min
Apr 23, 5:59 PM CDTTornado Warning Tornado observedOUNFoard, Hardeman, Wilbarger46 min
Apr 23, 6:08 PM CDTSevere Thunderstorm WarningOUNArcher, Baylor, Wichita52 min
Apr 23, 6:18 PM CDTTornado Warning Tornado observedConsiderable damage threatOUNFoard, Hardeman, Wilbarger42 min
Apr 23, 6:30 PM CDTSevere Thunderstorm WarningOUNComanche, Cotton, Kiowa, Tillman45 min
Apr 23, 6:43 PM CDTTornado Warning Tornado observedOUNWilbarger32 min
Apr 23, 6:57 PM CDTSevere Thunderstorm WarningOUNArcher, Wichita19 min
Apr 23, 7:01 PM CDTSevere Thunderstorm WarningOUNWichita, Wilbarger44 min
Apr 23, 7:06 PM CDTSevere Thunderstorm WarningOUNHarmon, Jackson39 min
Apr 23, 7:32 PM CDTSevere Thunderstorm WarningOUNArcher, Baylor, Wichita, Wilbarger43 min
Apr 23, 7:44 PM CDTSevere Thunderstorm WarningOUNArcher, Wichita46 min
Apr 23, 7:52 PM CDTSevere Thunderstorm WarningOUNCotton37 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

Norman, OK (KOUN), launched 12:00Z, 8.2 hours before the alert went out and 203 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, Norman, OK at 12:00Z on 2021-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 12:00Z on 2021-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 284 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
751 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
284 m²/s²
0-3 km storm-relative helicity
202 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

836 
WWUS20 KWNS 232010
SEL0  
SPC WW 232010
OKZ000-TXZ000-240200-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 100
NWS Storm Prediction Center Norman OK
315 PM CDT Fri Apr 23 2021

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  Southwest Oklahoma
  Western North Texas

* Effective this Friday afternoon and evening from 315 PM until
  900 PM CDT.

* Primary threats include...
  A few tornadoes possible
  Widespread large hail and isolated very large hail events to 3.5
    inches in diameter likely
  Scattered damaging wind gusts to 70 mph likely

SUMMARY...Isolated supercell thunderstorms are expected to develop
across the watch area this afternoon and early evening.  Very large
hail and damaging winds are the main threats, but the most intense
cells may also pose a risk of tornadoes.

The tornado watch area is approximately along and 60 statute miles
north and south of a line from 20 miles south southwest of Childress
TX to 45 miles east northeast of Wichita Falls TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU0).

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 98...WW 99...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 3.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 24035.

...Hart

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 23, 11:29 AM CDTMesoscale DiscussionSPCCarter, Jefferson, Love, Marshall91 min
Apr 23, 12:37 PM CDTSevere Thunderstorm WatchSPCBryan, Carter, Cotton, Jefferson, Johnston, Love and 3 more7 hr
Apr 23, 5:26 PM CDTMesoscale DiscussionSPCCotton, Jackson, Tillman2 hr
Apr 23, 12:43 PM CDTMesoscale DiscussionSPCBaylor, Childress, Collingsworth, Cottle, Foard, Hall and 2 more3 hr
Apr 23, 12:43 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Brazoria, Chambers, Cherokee, Fort Bend and 25 more2 hr
Apr 23, 2:00 PM CDTTornado WatchSPCAngelina, Austin, Brazos, Burleson, Chambers, Cherokee and 22 more7 hr
Apr 23, 3:27 PM CDTMesoscale DiscussionSPCBaylor, Foard, Hardeman, Wilbarger2 hr
Apr 23, 3:28 PM CDTMesoscale DiscussionSPCBosque, Brown, Comanche, Eastland, Erath, Hamilton and 11 more2 hr
Apr 23, 5:36 PM CDTMesoscale DiscussionSPCAngelina, Houston, Jasper, Nacogdoches, Newton, Polk and 7 more54 min
Apr 23, 6:46 PM CDTMesoscale DiscussionSPCAtascosa, Bell, Bexar, Blanco, Bosque, Burnet and 19 more89 min

Nearby

Tornado Watches in Texas, 2021Tornado Watches in Oklahoma, 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.