Alert archive / Texas / Tornado Watches in 2007

Tornado Watch 183

April 24, 200734 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 24, 2007, 10:53 PM CDT for 34 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2007, 10:53 PM CDT (03:53 UTC)
Expired
Apr 25, 2007, 6:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt
All 34 counties

Atascosa County, TX, Bandera County, TX, Bastrop County, TX, Bexar County, TX, Blanco County, TX, Burnet County, TX, Caldwell County, TX, Comal County, TX, DeWitt County, TX, Dimmit County, TX, Duval County, TX, Fayette County, TX, Frio County, TX, Gillespie County, TX, Gonzales County, TX, Guadalupe County, TX, Hays County, TX, Karnes County, TX, Kendall County, TX, Kerr County, TX, La Salle County, TX, Lavaca County, TX, Lee County, TX, Live Oak County, TX, Llano County, TX, Maverick County, TX, McMullen County, TX, Medina County, TX, Travis County, TX, Uvalde County, TX, Webb County, TX, Williamson County, TX, Wilson County, TX, Zavala County, TX

The radar

The Austin/San Antonio radar (KEWX), 75 km from the middle of the area, began a volume at 03:54 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
20%
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
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 24, 11:00 PM CDTSevere Thunderstorm WarningEWXMaverick46 min
Apr 24, 11:11 PM CDTSevere Thunderstorm WarningEWXMedina64 min
Apr 24, 11:18 PM CDTSevere Thunderstorm WarningEWXDimmit57 min
Apr 24, 11:43 PM CDTSevere Thunderstorm WarningEWXFrio48 min
Apr 24, 11:51 PM CDTSevere Thunderstorm WarningEWXAtascosa, Bexar54 min
Apr 25, 12:06 AM CDTFlash Flood WarningEWXBexar, Medina114 min
Apr 25, 12:08 AM CDTTornado WarningEWXAtascosa, Bexar37 min
Apr 25, 12:21 AM CDTSevere Thunderstorm WarningEWXComal, Guadalupe54 min
Apr 25, 12:33 AM CDTSevere Thunderstorm WarningCRPLa Salle44 min
Apr 25, 12:38 AM CDTSevere Thunderstorm WarningEWXBexar, Wilson48 min
Apr 25, 1:23 AM CDTSevere Thunderstorm WarningEWXCaldwell, Gonzales53 min
Apr 25, 1:36 AM CDTSevere Thunderstorm WarningEWXFayette, Lavaca54 min
Apr 25, 1:46 AM CDTTornado WarningEWXFayette, Gonzales29 min
Apr 25, 2:03 AM CDTTornado WarningEWXLavaca33 min
Apr 25, 2:06 AM CDTSevere Thunderstorm WarningEWXBastrop24 min
Apr 25, 2:53 AM CDTSevere Thunderstorm WarningEWXAtascosa37 min
Apr 25, 3:54 AM CDTSevere Thunderstorm WarningEWXDeWitt36 min
Apr 25, 4:26 AM CDTSevere Thunderstorm WarningEWXDeWitt19 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

Del Rio, TX (KDRT), launched 00:00Z, 3.9 hours before the alert went out and 202 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, Del Rio, TX at 00:00Z on 2007-04-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2857 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, Del Rio, TX at 00:00Z on 2007-04-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 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
2857 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
861 m above ground
0-6 km bulk shear
70 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
-4 m²/s²
Significant tornado parameter
1.9
Supercell composite
7.8

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 250340
SEL3  
SPC WW 250340
TXZ000-251100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 183
NWS STORM PREDICTION CENTER NORMAN OK
1040 PM CDT TUE APR 24 2007

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

       CENTRAL AND SOUTH CENTRAL TEXAS

EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 1040 PM
UNTIL 600 AM CDT.

TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH OF AUSTIN TEXAS
TO 25 MILES WEST SOUTHWEST OF LAREDO 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.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 179. WATCH NUMBER 179 WILL NOT BE IN EFFECT AFTER
1040 PM CDT. CONTINUE...WW 180...WW 181...WW 182...

DISCUSSION...INTENSE THUNDERSTORMS CONTINUE INVOF THE RIO GRANDE
RIVER LATE THIS EVENING WHERE AIR MASS IS VERY UNSTABLE.  MODERATE
TO STRONGLY UNSTABLE AIR MASS AND INTENSE LOW-DEEP LAYER SHEAR WILL
PERSIST ACROSS WW OVERNIGHT IN ADVANCE OF APPROACHING UPPER LOW AND
SURFACE COLD FRONT.  THIS WILL SUPPORT THREAT OF SEVERE
THUNDERSTORMS/SUPERCELLS...INCLUDING TORNADOES...WITH STORMS
DEVELOPING OVER THIS REGION OVERNIGHT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24035.


...EVANS

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 24, 7:33 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Collin, Dallas, Delta and 25 more117 min
Apr 24, 10:07 PM CDTMesoscale DiscussionSPCAnderson, Atascosa, Bandera, Bastrop, Bell, Bexar and 65 more83 min
Apr 24, 10:35 PM CDTTornado WatchSPCAnderson, Bell, Bosque, Bowie, Camp, Cass and 37 more5 hr
Apr 24, 11:58 PM CDTMesoscale DiscussionSPCAnderson, Bell, Bowie, Camp, Cass, Cherokee and 20 more92 min
Apr 25, 1:14 AM CDTMesoscale DiscussionSPCAtascosa, Bandera, Bastrop, Bee, Bexar, Blanco and 35 more91 min
Apr 25, 1:40 AM CDTTornado WatchSPCAransas, Austin, Bee, Brazoria, Brazos, Burleson and 30 more7 hr
Apr 25, 2:10 AM CDTMesoscale DiscussionSPCSabine, San Augustine, Shelby65 min
Apr 25, 4:29 AM CDTMesoscale DiscussionSPCAngelina, Aransas, Austin, Bee, Brazoria, Brazos and 35 more91 min
Apr 25, 7:36 AM CDTMesoscale DiscussionSPCAransas, Austin, Bee, Brazoria, Calhoun, Chambers and 28 more84 min
Apr 25, 9:00 AM CDTMesoscale DiscussionSPCBrazoria, Chambers, Galveston, Hardin, Harris, Jasper and 9 more60 min
Apr 25, 9:13 AM CDTTornado WatchSPCAransas, Brazoria, Calhoun, Chambers, Fort Bend, Galveston and 8 more8 hr
Apr 25, 3:05 PM CDTMesoscale DiscussionSPCGalveston55 min
Apr 25, 6:15 PM CDTMesoscale DiscussionSPCAngelina, Nacogdoches, Panola, Polk, San Augustine, Shelby and 2 more90 min

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.