Alert archive / Texas / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 198

April 24, 201146 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Apr 24, 2011, 11:43 PM CDT for 46 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2011, 11:43 PM CDT (04:43 UTC)
Expired
Apr 25, 2011, 5:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 46 counties

Bosque County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Comanche County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Eastland County, TX, Ellis County, TX, Erath County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Gregg County, TX, Hamilton County, TX, Henderson County, TX, Hill County, TX, Hood County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Mills County, TX, Montague County, TX, Morris County, TX, Navarro County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Smith County, TX, Somervell County, TX, Stephens County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wise County, TX, Wood County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 84 km from the middle of the area, began a volume at 04:43 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
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 25, 12:09 AM CDTSevere Thunderstorm WarningFWDComanche, Erath, Hamilton51 min
Apr 25, 12:09 AM CDTSevere Thunderstorm WarningSHVFranklin, Red River, Titus66 min
Apr 25, 12:26 AM CDTSevere Thunderstorm WarningFWDYoung49 min
Apr 25, 12:41 AM CDTSevere Thunderstorm WarningSHVBowie, Red River, Titus64 min
Apr 25, 12:58 AM CDTSevere Thunderstorm WarningFWDHamilton47 min
Apr 25, 1:13 AM CDTSevere Thunderstorm WarningFWDJack, Stephens, Young62 min
Apr 25, 1:56 AM CDTSevere Thunderstorm WarningFWDJack, Montague, Wise64 min
Apr 25, 2:23 AM CDTSevere Thunderstorm WarningFWDParker37 min
Apr 25, 2:56 AM CDTSevere Thunderstorm WarningFWDWise49 min
Apr 25, 3:21 AM CDTSevere Thunderstorm WarningFWDDenton, Tarrant54 min
Apr 25, 4:20 AM CDTSevere Thunderstorm WarningFWDTarrant55 min
Apr 25, 4:40 AM CDTSevere Thunderstorm WarningFWDDallas40 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

Fort Worth, TX (KFWD), launched 00:00Z, 4.7 hours before the alert went out and 103 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.

Skew-T log-pSkew-T log-p diagram, Fort Worth, TX at 00:00Z on 2011-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1679 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 00:00Z on 2011-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1679 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
1811 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
153 m²/s²
Significant tornado parameter
0.3
Supercell composite
6.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 24, 7:35 PM CDTMesoscale DiscussionSPCCarson, Gray, Hansford, Hemphill, Hutchinson, Lipscomb and 5 more2 hr
Apr 24, 8:48 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Collin, Comanche and 36 more117 min
Apr 24, 11:25 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Camp, Coke, Coleman and 39 more65 min
Apr 24, 11:58 PM CDTMesoscale DiscussionSPCHemphill, Lipscomb, Ochiltree92 min
Apr 25, 3:29 AM CDTMesoscale DiscussionSPCBosque, Camp, Collin, Dallas, Delta, Denton and 24 more61 min
Apr 25, 4:41 AM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Collin, Dallas, Delta and 21 more7 hr
Apr 25, 7:23 AM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Gregg, Harrison, Marion and 3 more97 min
Apr 25, 10:46 AM CDTMesoscale DiscussionSPCAnderson, Bosque, Bowie, Brazos, Camp, Cass and 42 more59 min
Apr 25, 11:00 AM CDTTornado WatchSPCBosque, Bowie, Camp, Cass, Collin, Cooke and 34 more7 hr
Apr 25, 1:28 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Collin, Cooke, Dallas and 30 more92 min
Apr 25, 2:16 PM CDTMesoscale DiscussionSPCAngelina, Bastrop, Bell, Blanco, Brazos, Burleson and 27 more59 min
Apr 25, 2:41 PM CDTTornado WatchSPCAnderson, Angelina, Bastrop, Bell, Blanco, Bosque and 49 more9 hr
Apr 25, 3:22 PM CDTTornado Watch PDSSPCBowie, Camp, Cass, Franklin, Gregg, Harrison and 7 more8 hr
Apr 25, 5:21 PM CDTMesoscale DiscussionSPCBosque, Delta, Ellis, Henderson, Hill, Hopkins and 7 more54 min
Apr 25, 5:24 PM CDTMesoscale DiscussionSPCArmstrong, Carson, Childress, Collingsworth, Donley, Gray and 3 more66 min
Apr 25, 6:57 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Bell, Blanco, Brazos, Burleson and 22 more2 hr

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.