Alert archive / Texas / Tornado Watches in 2006

Tornado Watch 261

April 29, 200624 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 29, 2006, 1:58 AM CDT for 24 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 29, 2006, 1:58 AM CDT (06:58 UTC)
Expired
Apr 29, 2006, 5:15 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 24 counties

Atascosa County, TX, Bandera County, TX, Bastrop County, TX, Bell County, TX, Bexar County, TX, Blanco County, TX, Caldwell County, TX, Comal County, TX, DeWitt County, TX, Falls County, TX, Fayette County, TX, Frio County, TX, Gonzales County, TX, Guadalupe County, TX, Hays County, TX, Karnes County, TX, Kendall County, TX, Lavaca County, TX, Lee County, TX, Medina County, TX, Milam County, TX, Travis County, TX, Williamson County, TX, Wilson County, TX

The radar

The Austin/San Antonio radar (KEWX), 25 km from the middle of the area, began a volume at 07:01 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
30%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
30%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 29, 2:11 AM CDTSevere Thunderstorm WarningFWDMilam64 min
Apr 29, 2:32 AM CDTSevere Thunderstorm WarningFWDFalls58 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 00:00Z, 7.0 hours before the alert went out and 247 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, Corpus Christi, TX at 00:00Z on 2006-04-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1970 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, Corpus Christi, TX at 00:00Z on 2006-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 square meters per square second.1939587897Sfc1 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
1970 J/kg
Mixed-layer CIN
-152 J/kg
Mixed-layer LCL
763 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
174 m²/s²
Significant tornado parameter
0.4
Supercell composite
2.6

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 290658
SEL1  
SPC WW 290658
TXZ000-291400-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 261
NWS STORM PREDICTION CENTER NORMAN OK
200 AM CDT SAT APR 29 2006

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

       SOUTH CENTRAL TEXAS

EFFECTIVE THIS SATURDAY MORNING FROM 200 AM UNTIL 900 AM CDT.

TORNADOES...HAIL TO 1.5 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 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 15 MILES SOUTHWEST OF HONDO
TEXAS TO 65 MILES EAST OF AUSTIN TEXAS.  FOR A COMPLETE DEPICTION
OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS
WOU1).

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 259. WATCH NUMBER 259 WILL NOT BE IN EFFECT AFTER
200 AM CDT. CONTINUE...WW 258...WW 260...

DISCUSSION...SMALL CONVECTIVE SYSTEMS WITH EMBEDDED SUPERCELLS MAY
MAINTAIN A THREAT FOR DAMAGING WIND GUSTS AND MARGINALLY SEVERE HAIL
AS THEY CONTINUE GENERALLY EWD AT 30 KTS.  AREA VWP/PROFILER DATA...
AND MODERATE/VERY MOIST SSELY SURFACE FLOW IN WARM SECTOR...ALSO
SUGGEST POTENTIAL FOR ISOLATED TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25035.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 28, 7:43 PM CDTTornado WatchSPCBandera, Bastrop, Bexar, Blanco, Burnet, Caldwell and 33 more6 hr
Apr 28, 8:44 PM CDTMesoscale DiscussionSPCClay, Collin, Cooke, Denton, Fannin, Grayson and 8 more91 min
Apr 28, 10:03 PM CDTMesoscale DiscussionSPCAnderson, Bastrop, Brazos, Burleson, Camp, Cass and 32 more87 min
Apr 28, 11:08 PM CDTTornado WatchSPCAnderson, Angelina, Austin, Bowie, Brazos, Burleson and 40 more7 hr
Apr 28, 11:14 PM CDTMesoscale DiscussionSPCBandera, Bexar, Edwards, Frio, Kendall, Kerr and 5 more91 min
Apr 29, 1:51 AM CDTMesoscale DiscussionSPCAtascosa, Austin, Bastrop, Bell, Bexar, Brazos and 24 more24 min
Apr 29, 4:03 AM CDTMesoscale DiscussionSPCAnderson, Angelina, Atascosa, Austin, Bastrop, Bell and 61 more57 min
Apr 29, 6:04 AM CDTTornado WatchSPCAngelina, Bowie, Brazoria, Camp, Cass, Chambers and 33 more7 hr
Apr 29, 7:37 AM CDTMesoscale DiscussionSPCAngelina, Bowie, Brazoria, Cass, Chambers, Galveston and 21 more83 min
Apr 29, 9:57 AM CDTMesoscale DiscussionSPCChambers, Hardin, Jefferson, Newton, Orange2 hr
Apr 29, 10:05 AM CDTMesoscale DiscussionSPCCollin, Cooke, Delta, Fannin, Grayson, Hunt and 2 more115 min
Apr 29, 11:55 AM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Franklin, Gregg, Harrison and 15 more65 min
Apr 29, 12:47 PM CDTTornado WatchSPCBowie, Camp, Cass, Franklin, Gregg, Harrison and 15 more8 hr

Nearby

Tornado Watches in Texas, 2006Every tornado watch in 2006

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.