Alert archive / Texas / Tornado Watches in 2008

Tornado Watch 929

November 10, 2008Cotton County, Tillman County, Oklahoma; 39 counties in Texas

The Storm Prediction Center issued this tornado watch at Nov 10, 2008, 12:25 PM CST for Cotton County, Tillman County, Oklahoma; 39 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Nov 10, 2008, 12:25 PM CST (18:25 UTC)
Expired
Nov 10, 2008, 7:00 PM CST
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 41 counties

Cotton County, OK, Tillman County, OK, Archer County, TX, Baylor County, TX, Blanco County, TX, Bosque County, TX, Brown County, TX, Burnet County, TX, Callahan County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Coryell County, TX, Eastland County, TX, Erath County, TX, Gillespie County, TX, Hamilton County, TX, Haskell County, TX, Hood County, TX, Jack County, TX, Jones County, TX, Kimble County, TX, Knox County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, Menard County, TX, Mills County, TX, Palo Pinto County, TX, Parker County, TX, Runnels County, TX, San Saba County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Taylor County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 14 km from the middle of the area, began a volume at 18:27 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
50%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Nov 10, 1:39 PM CSTSevere Thunderstorm WarningOUNCotton, Tillman51 min
Nov 10, 3:04 PM CSTTornado WarningFWDHood, Palo Pinto, Parker41 min
Nov 10, 3:05 PM CSTSevere Thunderstorm WarningFWDErath55 min
Nov 10, 3:47 PM CSTTornado WarningFWDErath, Hood28 min
Nov 10, 4:07 PM CSTSevere Thunderstorm WarningFWDParker38 min
Nov 10, 4:46 PM CSTSevere Thunderstorm WarningFWDErath, Palo Pinto44 min
Nov 10, 5:04 PM CSTSevere Thunderstorm WarningFWDErath26 min
Nov 10, 5:10 PM CSTFlash Flood WarningFWDErath, Palo Pinto2 hr
Nov 10, 5:29 PM CSTTornado WarningFWDErath31 min
Nov 10, 5:31 PM CSTSevere Thunderstorm WarningFWDHood, Palo Pinto, Parker59 min
Nov 10, 5:48 PM CSTFlash Flood WarningFWDHood, Parker3 hr

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 12:00Z, 6.4 hours before the alert went out and 174 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 12:00Z on 2008-11-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Fort Worth, TX at 12:00Z on 2008-11-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 380 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
882 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
380 m²/s²
0-3 km storm-relative helicity
483 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 101828
SEL9  
SPC WW 101828
OKZ000-TXZ000-110100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 929
NWS STORM PREDICTION CENTER NORMAN OK
1225 PM CST MON NOV 10 2008

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

       EXTREME SOUTHWEST OKLAHOMA
       CENTRAL AND NORTHWEST TEXAS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 1225 PM UNTIL
700 PM CST.

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 65 STATUTE
MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHWEST OF WICHITA
FALLS TEXAS TO 40 MILES EAST SOUTHEAST OF JUNCTION TEXAS.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).

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...THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS CENTRAL
TX WHERE LOW-LEVEL MOISTENING AND SURFACE HEATING HAVE ERODED
CONVECTIVE INHIBITION...AND ADDITIONAL THUNDERSTORM DEVELOPMENT
APPEARS LIKELY DURING THE AFTERNOON ALONG THE WARM FRONT AND DRYLINE
NEAR THE RED RIVER IN NW TX.  THOUGH MID LEVEL LAPSE RATES ARE NOT
PARTICULARLY STEEP AND CLOUDS HAVE LIMITED SURFACE HEATING THUS
FAR...GRADUAL MOISTENING AND CLOUD BREAKS W OF I-35 SHOULD ALLOW
SUFFICIENT DESTABILIZATION IN THE WARM SECTOR TO SUPPORT A SEVERE
STORM THREAT.  MLCAPE VALUES OF 500-1500 J/KG AND STRONG
LOW-LEVEL/DEEP LAYER SHEAR WILL SUPPORT SUPERCELLS CAPABLE OF
PRODUCING A FEW TORNADOES...ALONG WITH AT LEAST ISOLATED LARGE HAIL
AND DAMAGING WINDS.

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
450. MEAN STORM MOTION VECTOR 25030.


...THOMPSON

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 10, 12:59 PM CSTMesoscale DiscussionSPCBeaver, Texas91 min
Nov 10, 3:47 PM CSTMesoscale DiscussionSPCCotton, Jefferson, Tillman58 min
Nov 10, 9:03 AM CSTMesoscale DiscussionSPCCalhoun, Matagorda57 min
Nov 10, 11:33 AM CSTMesoscale DiscussionSPCBlanco, Bosque, Brown, Burnet, Callahan, Coleman and 25 more57 min

Nearby

Tornado Watches in Texas, 2008Tornado Watches in Oklahoma, 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.