Alert archive / Texas / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 231
The Storm Prediction Center issued this severe thunderstorm watch at May 31, 2021, 7:17 PM CDT for 8 counties in Texas. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- May 31, 2021, 7:17 PM CDT (00:17 UTC)
- Expired
- Jun 1, 2021, 3:00 AM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2.5 in
- Strongest gust expected
- 55 kt
Counties Dimmit County, TX, Edwards County, TX, Kinney County, TX, Maverick County, TX, Real County, TX, Uvalde County, TX, Val Verde County, TX, Zavala County, TX
The radar
The Laughlin AFB radar (KDFX), 59 km from the middle of the area, began a volume at 00:21 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
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 31, 9:23 PM CDT | Severe Thunderstorm Warning | EWX | Val Verde | 43 min |
| May 31, 9:48 PM CDT | Flash Flood Warning | EWX | Val Verde | 2 hr |
| May 31, 11:15 PM CDT | Severe Thunderstorm Warning | EWX | Kinney, Maverick | 60 min |
| May 31, 11:26 PM CDT | Flash Flood Warning | EWX | Kinney, Maverick | 3 hr |
| May 31, 11:47 PM CDT | Flash Flood Warning | EWX | Maverick | 3 hr |
| Jun 1, 12:08 AM CDT | Severe Thunderstorm Warning | EWX | Dimmit, Maverick, Zavala | 67 min |
| Jun 1, 12:44 AM CDT | Flash Flood Warning | EWX | Dimmit, Maverick, Zavala | 3 hr |
| Jun 1, 12:55 AM CDT | Severe Thunderstorm Warning | EWX | Dimmit, Frio, Maverick, Zavala | 65 min |
| Jun 1, 1:57 AM CDT | Severe Thunderstorm Warning | EWX | Dimmit, Frio, Zavala | 63 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
Del Rio, TX (KDRT), launched 00:00Z, 0.3 hours before the alert went out and 31 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
- 2624 J/kg
- Mixed-layer CIN
- -5 J/kg
- Mixed-layer LCL
- 922 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 176 m²/s²
- Significant tornado parameter
- 2.8
- Supercell composite
- 11.0
The text
As transmitted.
605
WWUS20 KWNS 010015
SEL1
SPC WW 010015
TXZ000-010600-
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 231
NWS Storm Prediction Center Norman OK
715 PM CDT Mon May 31 2021
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
South-Central Texas
* Effective this Monday night and Tuesday morning from 715 PM
until 100 AM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 2.5
inches in diameter possible
Isolated damaging wind gusts to 65 mph possible
A tornado or two possible
SUMMARY...An intense supercell ongoing near the Rio Grande River is
likely to continue southeastward potentially for a couple more hours
this evening, with additional storm development possible across/into
the southern Edwards Plateau/Rio Grande River vicinity in areas
along/south of a boundary.
The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 55 miles northwest of
Del Rio TX to 95 miles east southeast of Del Rio TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).
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.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
2.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
29020.
...GuyerSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 31, 10:07 PM CDT | Mesoscale Discussion | SPC | Dimmit, Maverick, Zavala | 83 min |
| Jun 1, 12:09 AM CDT | Severe Thunderstorm Watch | SPC | Brooks, Duval, Jim Hogg, Jim Wells, La Salle, McMullen and 2 more | 6 hr |
| Jun 1, 12:44 AM CDT | Mesoscale Discussion | SPC | Dimmit, La Salle, Maverick, Zavala | 91 min |
| Jun 1, 2:50 AM CDT | Mesoscale Discussion | SPC | La Salle, McMullen, Webb | 85 min |
| Jun 1, 2:14 PM CDT | Mesoscale Discussion | SPC | Dallam, Hartley | 2 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.