Alert archive / Texas / Severe Thunderstorm Watches in 2021
Severe Thunderstorm Watch 96
The Storm Prediction Center issued this severe thunderstorm watch at Apr 15, 2021, 8:36 AM CDT for 25 counties in Texas. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 15, 2021, 8:36 AM CDT (13:36 UTC)
- Expired
- Apr 15, 2021, 5:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 60 kt
All 25 counties
Bandera County, TX, Blanco County, TX, Burnet County, TX, Concho County, TX, Crockett County, TX, Edwards County, TX, Gillespie County, TX, Irion County, TX, Kendall County, TX, Kerr County, TX, Kimble County, TX, Kinney County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, Medina County, TX, Menard County, TX, Real County, TX, San Saba County, TX, Schleicher County, TX, Sutton County, TX, Tom Green County, TX, Uvalde County, TX, Val Verde County, TX, Williamson County, TX
The radar
The San Angelo radar (KSJT), 138 km from the middle of the area, began a volume at 13:36 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
- 5%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 70%
- One or more hailstones of 2 inches or more
- 70%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
25 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 15, 8:40 AM CDT | Severe Thunderstorm Warning | EWX | Kinney | 65 min |
| Apr 15, 9:01 AM CDT | Severe Thunderstorm Warning | SJT | Schleicher, Sutton | 44 min |
| Apr 15, 9:04 AM CDT | Severe Thunderstorm Warning | EWX | Edwards | 24 min |
| Apr 15, 9:32 AM CDT | Severe Thunderstorm Warning | EWX | Edwards | 17 min |
| Apr 15, 9:34 AM CDT | Severe Thunderstorm Warning | SJT | Kimble, Sutton | 41 min |
| Apr 15, 9:42 AM CDT | Severe Thunderstorm Warning | EWX | Kinney, Uvalde | 63 min |
| Apr 15, 9:45 AM CDT | Severe Thunderstorm Warning | SJT | Kimble, Menard, Schleicher, Sutton | 45 min |
| Apr 15, 10:03 AM CDT | Severe Thunderstorm Warning | SJT | Kimble, Menard | 42 min |
| Apr 15, 10:27 AM CDT | Severe Thunderstorm Warning | SJT | McCulloch, Menard | 33 min |
| Apr 15, 10:34 AM CDT | Severe Thunderstorm Warning | SJT | Kimble | 41 min |
| Apr 15, 10:42 AM CDT | Severe Thunderstorm Warning | EWX | Uvalde | 45 min |
| Apr 15, 10:54 AM CDT | Severe Thunderstorm Warning | SJT | McCulloch, Mason, Menard | 51 min |
| Apr 15, 11:31 AM CDT | Severe Thunderstorm Warning | SJT | Brown, McCulloch, San Saba | 44 min |
| Apr 15, 11:58 AM CDT | Severe Thunderstorm Warning | SJT | Brown, McCulloch, San Saba | 47 min |
| Apr 15, 12:00 PM CDT | Severe Thunderstorm Warning | SJT | Mason | 45 min |
| Apr 15, 12:15 PM CDT | Severe Thunderstorm Warning | EWX | Gillespie, Llano | 60 min |
| Apr 15, 1:07 PM CDT | Severe Thunderstorm Warning | EWX | Blanco, Burnet, Llano, Travis | 53 min |
| Apr 15, 1:52 PM CDT | Severe Thunderstorm Warning | EWX | Burnet, Williamson | 36 min |
| Apr 15, 2:07 PM CDT | Severe Thunderstorm Warning | EWX | Burnet, Williamson | 40 min |
| Apr 15, 2:18 PM CDT | Severe Thunderstorm Warning | SJT | San Saba | 16 min |
| Apr 15, 2:38 PM CDT | Severe Thunderstorm Warning | SJT | San Saba | 37 min |
| Apr 15, 2:57 PM CDT | Severe Thunderstorm Warning | EWX | Burnet, Llano | 63 min |
| Apr 15, 3:21 PM CDT | Severe Thunderstorm Warning | EWX | Burnet, Williamson | 54 min |
| Apr 15, 3:56 PM CDT | Severe Thunderstorm Warning | EWX | Travis, Williamson | 49 min |
| Apr 15, 4:36 PM CDT | Severe Thunderstorm Warning | EWX | Bastrop, Lee, Travis, Williamson | 54 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 12:00Z, 1.6 hours before the alert went out and 165 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
- 2593 J/kg
- Mixed-layer CIN
- -44 J/kg
- Mixed-layer LCL
- 634 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 169 m²/s²
- 0-3 km storm-relative helicity
- 338 m²/s²
- Significant tornado parameter
- 4.6
- Supercell composite
- 21.4
The text
As transmitted.
125
WWUS20 KWNS 151333
SEL6
SPC WW 151333
TXZ000-152000-
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 96
NWS Storm Prediction Center Norman OK
835 AM CDT Thu Apr 15 2021
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
The Edwards Plateau of central Texas
* Effective this Thursday morning and afternoon from 835 AM until
300 PM CDT.
* Primary threats include...
Scattered large hail and isolated very large hail events to 3
inches in diameter likely
Isolated damaging wind gusts to 70 mph possible
SUMMARY...Elevated supercells are expected through the morning and
potentially into the early afternoon across the Edwards Plateau and
parts of the Hill Country. The storm environment will favor the
potential for isolated very large hail (baseball size or larger),
along with isolated damaging gusts.
The severe thunderstorm watch area is approximately along and 90
statute miles east and west of a line from 55 miles north northeast
of Junction TX to 25 miles southeast of Del Rio TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).
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
3 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
27020.
...ThompsonSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 15, 8:17 AM CDT | Mesoscale Discussion | SPC | Atascosa, Bandera, Bexar, Blanco, Comal, Edwards and 13 more | 2 hr |
| Apr 15, 10:56 AM CDT | Mesoscale Discussion | SPC | Bandera, Concho, Edwards, Gillespie, Kerr, Kimble and 9 more | 94 min |
| Apr 15, 12:24 PM CDT | Mesoscale Discussion | SPC | Bastrop, Bell, Blanco, Burnet, Coryell, Falls and 12 more | 2 hr |
| Apr 15, 4:55 PM CDT | Mesoscale Discussion | SPC | Austin, Brazoria, Burleson, Fort Bend, Harris, Lee and 4 more | 3 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.