Alert archive / Texas / Tornado Watches in 2007

Tornado Watch 133

April 13, 200733 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 13, 2007, 12:27 PM CDT for 33 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 13, 2007, 12:27 PM CDT (17:27 UTC)
Expired
Apr 13, 2007, 7:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
70 kt
All 33 counties

Archer County, TX, Baylor County, TX, Brown County, TX, Callahan County, TX, Clay County, TX, Coke County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Eastland County, TX, Erath County, TX, Fisher County, TX, Foard County, TX, Hardeman County, TX, Haskell County, TX, Irion County, TX, Jack County, TX, Jones County, TX, King County, TX, Knox County, TX, Nolan County, TX, Palo Pinto County, TX, Runnels County, TX, Shackelford County, TX, Stephens County, TX, Sterling County, TX, Stonewall County, TX, Taylor County, TX, Throckmorton County, TX, Tom Green County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 51 km from the middle of the area, began a volume at 17:28 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
70%
One or more EF2 to EF5 tornadoes
40%
Ten or more severe wind reports
40%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
70%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 13, 1:06 PM CDTSevere Thunderstorm WarningLUBStonewall24 min
Apr 13, 1:13 PM CDTSevere Thunderstorm WarningSJTHaskell32 min
Apr 13, 1:28 PM CDTTornado WarningSJTHaskell32 min
Apr 13, 1:36 PM CDTSevere Thunderstorm WarningOUNFoard, Knox39 min
Apr 13, 1:51 PM CDTTornado WarningSJTHaskell24 min
Apr 13, 2:12 PM CDTTornado WarningOUNBaylor, Knox33 min
Apr 13, 2:17 PM CDTSevere Thunderstorm WarningOUNFoard, Wilbarger43 min
Apr 13, 2:40 PM CDTTornado WarningOUNBaylor35 min
Apr 13, 3:05 PM CDTSevere Thunderstorm WarningOUNArcher, Wichita40 min
Apr 13, 3:16 PM CDTSevere Thunderstorm WarningFWDStephens59 min
Apr 13, 3:16 PM CDTSevere Thunderstorm WarningOUNBaylor29 min
Apr 13, 3:16 PM CDTTornado WarningOUNArcher44 min
Apr 13, 3:33 PM CDTSevere Thunderstorm WarningSJTCallahan17 min
Apr 13, 3:46 PM CDTSevere Thunderstorm WarningOUNClay, Wichita44 min
Apr 13, 3:56 PM CDTSevere Thunderstorm WarningFWDYoung49 min
Apr 13, 3:56 PM CDTTornado WarningOUNArcher34 min
Apr 13, 4:13 PM CDTSevere Thunderstorm WarningFWDPalo Pinto, Stephens62 min
Apr 13, 4:14 PM CDTSevere Thunderstorm WarningFWDJack61 min
Apr 13, 4:30 PM CDTSevere Thunderstorm WarningOUNClay45 min
Apr 13, 4:49 PM CDTTornado WarningFWDPalo Pinto56 min
Apr 13, 5:09 PM CDTSevere Thunderstorm WarningFWDPalo Pinto41 min
Apr 13, 5:20 PM CDTSevere Thunderstorm WarningFWDComanche, Eastland, Erath70 min
Apr 13, 5:26 PM CDTSevere Thunderstorm WarningSJTBrown34 min
Apr 13, 5:36 PM CDTSevere Thunderstorm WarningSJTBrown, San Saba39 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, 5.5 hours before the alert went out and 233 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, Midland Regional, TX at 12:00Z on 2007-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1836 joules per kilogram.LCLLFCEL10008507005003002001001 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, Midland Regional, TX at 12:00Z on 2007-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 122 square meters per square second.1939587897117Sfc1 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
1836 J/kg
Mixed-layer CIN
-79 J/kg
Mixed-layer LCL
808 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
122 m²/s²
0-3 km storm-relative helicity
200 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.2

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 131728
SEL3  
SPC WW 131728
TXZ000-140000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 133
NWS STORM PREDICTION CENTER NORMAN OK
1230 PM CDT FRI APR 13 2007

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       NORTHWEST TEXAS

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 1230 PM UNTIL
700 PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES EAST AND WEST OF A LINE FROM 70 MILES WEST SOUTHWEST OF
BROWNWOOD TEXAS TO 20 MILES WEST NORTHWEST OF WICHITA FALLS
TEXAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED
WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

DISCUSSION...SCATTERED THUNDERSTORMS WILL DEVELOP EARLY THIS
AFTERNOON ALONG DRYLINE WEST OF ABI-SJT.  THESE STORMS WILL MOVE
EASTWARD INTO AN INCREASINGLY MOIST AND UNSTABLE AIR MASS.  BACKED
LOW LEVEL WINDS AND OBSERVED VERTICAL SHEAR PROFILES APPEAR VERY
FAVORABLE FOR SUPERCELLS CAPABLE OF TORNADOES...AS WELL AS VERY
LARGE HAIL AND DAMAGING WINDS.  STRONG TORNADOES ARE POSSIBLE.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25035.


...HART

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 12, 7:37 PM CDTMesoscale DiscussionSPCBaylor, Collingsworth, Foard, Hardeman, Wheeler, Wichita and 1 more113 min
Apr 12, 9:35 PM CDTMesoscale DiscussionSPCArmstrong, Bailey, Briscoe, Carson, Castro, Childress and 35 more115 min
Apr 12, 11:31 PM CDTMesoscale DiscussionSPCAndrews, Armstrong, Bailey, Borden, Briscoe, Carson and 38 more119 min
Apr 12, 11:46 PM CDTSevere Thunderstorm WatchSPCAndrews, Armstrong, Bailey, Baylor, Borden, Briscoe and 63 more7 hr
Apr 13, 2:36 AM CDTMesoscale DiscussionSPCArmstrong, Briscoe, Carson, Castro, Childress, Collingsworth and 23 more84 min
Apr 13, 5:34 AM CDTMesoscale DiscussionSPCArcher, Armstrong, Baylor, Briscoe, Callahan, Carson and 32 more86 min
Apr 13, 12:12 PM CDTMesoscale DiscussionSPCArcher, Baylor, Fisher, Haskell, Hood, Jack and 8 more63 min
Apr 13, 12:37 PM CDTMesoscale DiscussionSPCFoard, Hardeman, Wichita, Wilbarger113 min
Apr 13, 2:51 PM CDTMesoscale DiscussionSPCAnderson, Bell, Bosque, Cherokee, Collin, Cooke and 31 more54 min
Apr 13, 5:08 PM CDTMesoscale DiscussionSPCAngelina, Chambers, Cherokee, Hardin, Harris, Harrison and 18 more97 min
Apr 13, 5:43 PM CDTTornado Watch PDSSPCBell, Bosque, Collin, Cooke, Coryell, Dallas and 22 more4 hr
Apr 13, 5:48 PM CDTTornado Watch PDSSPCAnderson, Angelina, Bowie, Brazos, Burleson, Camp and 39 more8 hr
Apr 13, 5:58 PM CDTMesoscale DiscussionSPCBandera, Blanco, Burnet, Edwards, Gillespie, Hays and 16 more62 min
Apr 13, 6:27 PM CDTTornado WatchSPCAtascosa, Bandera, Bastrop, Bexar, Blanco, Burnet and 26 more8 hr

Nearby

Tornado Watches in Texas, 2007Every tornado 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; radar from the NEXRAD Level II archive.