Alert archive / Texas / Severe Thunderstorm Watches in 2012
Severe Thunderstorm Watch 139
The Storm Prediction Center issued this severe thunderstorm watch at Apr 4, 2012, 12:55 PM CDT for 25 counties in Texas. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 4, 2012, 12:55 PM CDT (17:55 UTC)
- Expired
- Apr 4, 2012, 7:11 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 25 counties
Aransas County, TX, Bee County, TX, Brazoria County, TX, Brooks County, TX, Calhoun County, TX, Cameron County, TX, Duval County, TX, Fort Bend County, TX, Galveston County, TX, Goliad County, TX, Hidalgo County, TX, Jackson County, TX, Jim Hogg County, TX, Jim Wells County, TX, Kenedy County, TX, Kleberg County, TX, Live Oak County, TX, Matagorda County, TX, Nueces County, TX, Refugio County, TX, San Patricio County, TX, Starr County, TX, Victoria County, TX, Wharton County, TX, Willacy County, TX
The radar
The Corpus Christi radar (KCRP), 101 km from the middle of the area, began a volume at 17:53 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
- 5%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 40%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 4, 1:02 PM CDT | Tornado Warning | HGX | Brazoria, Galveston | 43 min |
| Apr 4, 1:20 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria | 40 min |
| Apr 4, 1:35 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Galveston | 40 min |
| Apr 4, 1:59 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Matagorda | 46 min |
| Apr 4, 2:12 PM CDT | Severe Thunderstorm Warning | HGX | Galveston | 25 min |
| Apr 4, 2:42 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Matagorda | 48 min |
| Apr 4, 3:05 PM CDT | Severe Thunderstorm Warning | CRP | Calhoun, Refugio | 40 min |
| Apr 4, 3:23 PM CDT | Severe Thunderstorm Warning | HGX | Jackson, Matagorda | 52 min |
| Apr 4, 3:30 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Galveston, Matagorda | 45 min |
| Apr 4, 3:39 PM CDT | Severe Thunderstorm Warning | CRP | Calhoun | 66 min |
| Apr 4, 3:45 PM CDT | Severe Thunderstorm Warning | CRP | Calhoun | 30 min |
| Apr 4, 3:54 PM CDT | Severe Thunderstorm Warning | CRP | Aransas, Refugio | 36 min |
| Apr 4, 4:13 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Jackson, Matagorda | 62 min |
| Apr 4, 4:51 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Fort Bend, Jackson, Matagorda, Wharton | 54 min |
| Apr 4, 5:07 PM CDT | Severe Thunderstorm Warning | HGX | Jackson, Matagorda, Wharton | 53 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
Corpus Christi, TX (KCRP), launched 12:00Z, 5.9 hours before the alert went out and 94 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
- 3692 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 499 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- -42 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- -0.5
- Supercell composite
- -3.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 3, 7:35 PM CDT | Severe Thunderstorm Watch | SPC | Austin, Bastrop, Brazos, Burleson, Colorado, Fayette and 13 more | 7 hr |
| Apr 3, 8:47 PM CDT | Mesoscale Discussion | SPC | Angelina, Cherokee, Houston, Nacogdoches, Panola, Rusk and 3 more | 58 min |
| Apr 3, 9:48 PM CDT | Severe Thunderstorm Watch | SPC | Angelina, Cherokee, Hardin, Jasper, Jefferson, Nacogdoches and 8 more | 8 hr |
| Apr 3, 11:24 PM CDT | Mesoscale Discussion | SPC | Angelina, Austin, Colorado, Jasper, Lavaca, Montgomery and 10 more | 96 min |
| Apr 4, 2:29 AM CDT | Mesoscale Discussion | SPC | Chambers, Hardin, Harris, Jefferson, Liberty, Orange and 2 more | 91 min |
| Apr 4, 12:19 PM CDT | Mesoscale Discussion | SPC | Aransas, Austin, Bee, Brazoria, Calhoun, Chambers and 25 more | 86 min |
| Apr 4, 3:32 PM CDT | Mesoscale Discussion | SPC | Aransas, Brazoria, Calhoun, Galveston, Kleberg, Matagorda and 1 more | 88 min |
Nearby
Severe Thunderstorm Watches in Texas, 2012Every severe thunderstorm watch in 2012
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.