Alert archive / Texas / Tornado Watches in 2008

Tornado Watch 155

April 3, 20087 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 3, 2008, 4:40 PM CDT for 7 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Apr 3, 2008, 4:40 PM CDT (21:40 UTC)
Expired
Apr 3, 2008, 7:26 PM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
4 in
Strongest gust expected
60 kt

Counties Crockett County, TX, Edwards County, TX, Kinney County, TX, Schleicher County, TX, Sutton County, TX, Terrell County, TX, Val Verde County, TX

The radar

The Laughlin AFB radar (KDFX), 153 km from the middle of the area, began a volume at 21:42 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
20%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
20%
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
80%
Six or more combined severe hail and wind reports
50%

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 12:00Z, 9.7 hours before the alert went out and 108 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 12:00Z on 2008-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 749 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 12:00Z on 2008-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 226 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
749 J/kg
Mixed-layer CIN
-436 J/kg
Mixed-layer LCL
635 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
226 m²/s²
0-3 km storm-relative helicity
362 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 032141
SEL5  
SPC WW 032141
TXZ000-040200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 155
NWS STORM PREDICTION CENTER NORMAN OK
440 PM CDT THU APR 3 2008

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

       SOUTHWEST TEXAS

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 440 PM UNTIL
900 PM CDT.

TORNADOES...HAIL TO 4 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 55 MILES SOUTHEAST OF DRYDEN
TEXAS TO 110 MILES NORTHEAST OF DRYDEN TEXAS.  FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU5).

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...CONTINUE...WW 153...WW 154...

DISCUSSION...INTENSE SUPERCELL IN TERRELL COUNTY TX CONTINUES EARLY
THIS EVENING.  ENVIRONMENT IS VERY UNSTABLE BUT CAP STRENGTHENS WITH
EWD EXTENT.  HOWEVER...VERY STRONG DEEP LAYER SHEAR WILL CONTINUE TO
SUPPORT SUPERCELLS AND LIKELY VERY LARGE HAIL WITH MID/UPPER JET
OVERSPREADING THE REGION.  AN ISOLATED TORNADO OR TWO IS ALSO
POSSIBLE...ALONG WITH DAMAGING WINDS...WITH ANY PERSISTENT
SUPERCELL.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 4 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 27030.


...EVANS

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 3, 10:47 AM CDTMesoscale DiscussionSPCClay, Collin, Cooke, Dallas, Delta, Denton and 23 more58 min
Apr 3, 1:42 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Coke, Coleman and 20 more93 min
Apr 3, 2:04 PM CDTTornado WatchSPCArcher, Baylor, Callahan, Clay, Cooke, Eastland and 16 more6 hr
Apr 3, 3:28 PM CDTMesoscale DiscussionSPCCoke, Crockett, Glasscock, Irion, Reagan, Sterling and 3 more62 min
Apr 3, 5:32 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Collin, Cooke, Dallas and 24 more58 min
Apr 3, 5:54 PM CDTTornado WatchSPCBowie, Camp, Cass, Collin, Delta, Denton and 9 more3 hr
Apr 3, 6:12 PM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Cooke, Jack, Montague and 6 more2 hr

Nearby

Tornado Watches in Texas, 2008Every tornado watch in 2008

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.