Alert archive / Texas / Tornado Watches in 2011

Tornado Watch 223

April 26, 201135 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 26, 2011, 9:42 PM CDT for 35 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 26, 2011, 9:42 PM CDT (02:42 UTC)
Expired
Apr 27, 2011, 5:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
65 kt
All 35 counties

Anderson County, TX, Angelina County, TX, Bell County, TX, Brazos County, TX, Burleson County, TX, Cherokee County, TX, Falls County, TX, Freestone County, TX, Grimes County, TX, Hardin County, TX, Harrison County, TX, Houston County, TX, Jasper County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Limestone County, TX, Madison County, TX, Milam County, TX, Montgomery County, TX, Nacogdoches County, TX, Newton County, TX, Panola County, TX, Polk County, TX, Robertson County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Washington County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 109 km from the middle of the area, began a volume at 02:44 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
40%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
40%
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
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 26, 9:48 PM CDTTornado WarningFWDLeon42 min
Apr 26, 9:51 PM CDTSevere Thunderstorm WarningFWDAnderson54 min
Apr 26, 9:56 PM CDTTornado WarningFWDLeon, Limestone, Robertson49 min
Apr 26, 9:56 PM CDTSevere Thunderstorm WarningSHVHarrison, Panola49 min
Apr 26, 9:59 PM CDTSevere Thunderstorm WarningFWDFalls38 min
Apr 26, 10:03 PM CDTTornado WarningHGXHouston42 min
Apr 26, 10:27 PM CDTSevere Thunderstorm WarningFWDLeon48 min
Apr 26, 10:41 PM CDTSevere Thunderstorm WarningFWDLimestone34 min
Apr 26, 10:41 PM CDTTornado WarningFWDLeon, Robertson49 min
Apr 26, 10:43 PM CDTTornado WarningHGXHouston47 min
Apr 26, 11:11 PM CDTSevere Thunderstorm WarningFWDLeon, Limestone, Robertson41 min
Apr 26, 11:15 PM CDTTornado WarningHGXHouston, Trinity45 min
Apr 26, 11:20 PM CDTSevere Thunderstorm WarningFWDLeon55 min
Apr 26, 11:20 PM CDTSevere Thunderstorm WarningSHVAngelina, Cherokee, Nacogdoches, Sabine, San Augustine55 min
Apr 26, 11:28 PM CDTTornado WarningHGXHouston, Madison, Trinity, Walker47 min
Apr 26, 11:34 PM CDTSevere Thunderstorm WarningSHVNacogdoches, Panola, San Augustine, Shelby56 min
Apr 26, 11:38 PM CDTTornado WarningFWDLeon33 min
Apr 26, 11:55 PM CDTTornado WarningHGXHouston, Polk, Trinity50 min
Apr 27, 12:07 AM CDTTornado WarningHGXHouston, Trinity38 min
Apr 27, 12:23 AM CDTSevere Thunderstorm WarningSHVAngelina, Nacogdoches, Sabine, San Augustine, Shelby67 min
Apr 27, 12:32 AM CDTTornado WarningHGXHouston, Trinity43 min
Apr 27, 12:40 AM CDTTornado WarningLCHJasper, Tyler50 min
Apr 27, 12:55 AM CDTTornado WarningHGXPolk35 min
Apr 27, 1:28 AM CDTTornado WarningSHVAngelina, San Augustine32 min
Apr 27, 1:33 AM CDTSevere Thunderstorm WarningSHVSabine42 min
Apr 27, 1:35 AM CDTTornado WarningLCHJasper, Newton23 min
Apr 27, 2:00 AM CDTTornado WarningSHVSabine, San Augustine47 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, 2.7 hours before the alert went out and 213 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 2011-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1466 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 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 2011-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 65 square meters per square second.1939587897117136Sfc1 km3 km6 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
1466 J/kg
Mixed-layer CIN
-154 J/kg
Mixed-layer LCL
1066 m above ground
0-6 km bulk shear
83 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
212 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 26, 7:08 PM CDTMesoscale DiscussionSPCArcher, Baylor, Childress, Clay, Collingsworth, Foard and 13 more97 min
Apr 26, 8:53 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Austin, Bastrop, Bell, Bowie and 58 more97 min
Apr 26, 11:33 PM CDTMesoscale DiscussionSPCAngelina, Brazos, Burleson, Falls, Grimes, Houston and 18 more117 min
Apr 27, 3:29 AM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Delta and 22 more2 hr
Apr 27, 4:53 AM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Cherokee, Franklin, Gregg and 9 more5 hr
Apr 27, 9:48 AM CDTMesoscale DiscussionSPCHarrison, Marion, Panola27 min

Nearby

Tornado Watches in Texas, 2011Every tornado 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.