Alert archive / Texas / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 537
The Storm Prediction Center issued this severe thunderstorm watch at Jun 22, 2011, 12:47 AM CDT for 41 counties in Texas. It was in force for 3 hr.
The area
The outline as issued.
The facts
- Issued
- Jun 22, 2011, 12:47 AM CDT (05:47 UTC)
- Expired
- Jun 22, 2011, 3:34 AM CDT
- In force
- 3 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 55 kt
All 41 counties
Atascosa County, TX, Austin County, TX, Bandera County, TX, Bastrop County, TX, Bexar County, TX, Blanco County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Colorado County, TX, Comal County, TX, DeWitt County, TX, Dimmit County, TX, Fayette County, TX, Frio County, TX, Gonzales County, TX, Grimes County, TX, Guadalupe County, TX, Hays County, TX, Houston County, TX, Karnes County, TX, Kendall County, TX, La Salle County, TX, Lavaca County, TX, Lee County, TX, Live Oak County, TX, Madison County, TX, McMullen County, TX, Medina County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Travis County, TX, Trinity County, TX, Uvalde County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Williamson County, TX, Wilson County, TX, Zavala County, TX
The radar
The Ft Hood radar (KGRK), 75 km from the middle of the area, began a volume at 05:48 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
- 10%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 60%
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Fort Worth, TX (KFWD), launched 00:00Z, 5.8 hours before the alert went out and 300 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
- 2454 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 1858 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 32 m²/s²
- 0-3 km storm-relative helicity
- 98 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 4.8
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 7:59 PM CDT | Mesoscale Discussion | SPC | Bell, Blanco, Bosque, Brewster, Brown, Burnet and 48 more | 61 min |
| Jun 21, 10:51 PM CDT | Mesoscale Discussion | SPC | Brazos, Falls, Freestone, Houston, Leon, Limestone and 4 more | 84 min |
| Jun 22, 12:29 AM CDT | Mesoscale Discussion | SPC | Austin, Bastrop, Bexar, Brazos, Burleson, Caldwell and 29 more | 31 min |
| Jun 22, 3:54 AM CDT | Mesoscale Discussion | SPC | Austin, Bee, Colorado, Goliad, Grimes, La Salle and 8 more | 66 min |
Nearby
Severe Thunderstorm Watches in Texas, 2011Every severe thunderstorm watch in 2011
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.