Alert archive / Texas / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 284
The Storm Prediction Center issued this severe thunderstorm watch at May 21, 2007, 3:17 PM CDT for 15 counties in Texas. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- May 21, 2007, 3:17 PM CDT (20:17 UTC)
- Expired
- May 21, 2007, 11:00 PM CDT
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 3 in
- Strongest gust expected
- 60 kt
Counties Brewster County, TX, Crane County, TX, Crockett County, TX, Edwards County, TX, Jeff Davis County, TX, Kinney County, TX, Pecos County, TX, Presidio County, TX, Reagan County, TX, Reeves County, TX, Schleicher County, TX, Sutton County, TX, Terrell County, TX, Upton County, TX, Val Verde County, TX
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
- 5%
- Ten or more severe wind reports
- 20%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 4:43 PM CDT | Severe Thunderstorm Warning | MAF | Brewster | 62 min |
| May 21, 9:04 PM CDT | Flash Flood Warning | EWX | Val Verde | 3 hr |
| May 21, 9:26 PM CDT | Severe Thunderstorm Warning | EWX | Val Verde | 64 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, 8.3 hours before the alert went out and 167 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
- 402 J/kg
- Mixed-layer CIN
- -189 J/kg
- Mixed-layer LCL
- 743 m above ground
- 0-6 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- 63 m²/s²
- 0-3 km storm-relative helicity
- 34 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 21, 2:17 PM CDT | Mesoscale Discussion | SPC | Anderson, Austin, Bell, Bosque, Brazoria, Brazos and 35 more | 58 min |
| May 21, 2:51 PM CDT | Mesoscale Discussion | SPC | Brewster, Crane, Crockett, Ector, Irion, Midland and 9 more | 84 min |
| May 21, 3:55 PM CDT | Mesoscale Discussion | SPC | Carson, Gray, Hansford, Hutchinson, Moore, Ochiltree and 3 more | 65 min |
| May 21, 4:06 PM CDT | Severe Thunderstorm Watch | SPC | Armstrong, Carson, Collingsworth, Deaf Smith, Donley, Gray and 12 more | 7 hr |
| May 21, 6:03 PM CDT | Mesoscale Discussion | SPC | Hemphill, Lipscomb, Ochiltree, Roberts | 87 min |
Nearby
Severe Thunderstorm Watches in Texas, 2007Every severe thunderstorm watch in 2007
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.