Alert archive / Texas / Tornado Watches in 2008
Tornado Watch 930
The Storm Prediction Center issued this tornado watch at Nov 10, 2008, 6:37 PM CST for 21 counties in Texas. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Nov 10, 2008, 6:37 PM CST (00:37 UTC)
- Expired
- Nov 11, 2008, 2:00 AM CST
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 21 counties
Bosque County, TX, Brown County, TX, Coleman County, TX, Comanche County, TX, Coryell County, TX, Dallas County, TX, Ellis County, TX, Erath County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Johnson County, TX, Lampasas County, TX, McCulloch County, TX, McLennan County, TX, Mills County, TX, Navarro County, TX, Parker County, TX, San Saba County, TX, Somervell County, TX, Tarrant County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 71 km from the middle of the area, began a volume at 00:41 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
- 10%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 10, 7:29 PM CST | Flash Flood Warning | FWD | Collin, Denton, Tarrant | 3 hr |
| Nov 10, 7:30 PM CST | Severe Thunderstorm Warning | FWD | Erath | 45 min |
| Nov 10, 7:38 PM CST | Flash Flood Warning | FWD | Comanche, Erath | 3 hr |
| Nov 10, 8:41 PM CST | Flash Flood Warning | FWD | Hood, Parker | 2 hr |
| Nov 10, 8:59 PM CST | Flash Flood Warning | FWD | Collin, Dallas, Tarrant | 3 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 00:00Z, 0.6 hours before the alert went out and 97 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.
- Mixed-layer CAPE
- 182 J/kg
- Mixed-layer CIN
- -60 J/kg
- Mixed-layer LCL
- 508 m above ground
- 0-6 km bulk shear
- 57 kt
- 0-1 km storm-relative helicity
- 336 m²/s²
- 0-3 km storm-relative helicity
- 457 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 10.4
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 110037
SEL0
SPC WW 110037
TXZ000-110800-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 930
NWS STORM PREDICTION CENTER NORMAN OK
640 PM CST MON NOV 10 2008
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
CENTRAL TEXAS
EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 640 PM UNTIL
200 AM 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 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 45 MILES SOUTH SOUTHEAST OF
DALLAS TEXAS TO 45 MILES SOUTHWEST OF BROWNWOOD TEXAS. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU0).
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 929...
DISCUSSION...LINE OF INTENSE THUNDERSTORMS EXTENDS FROM EAST OF SJT
TO WEST OF DFW. THESE STORMS WILL REMAIN STRONG THROUGH THE EVENING
AS LOW LEVEL MOISTURE AND INSTABILITY SLOWLY INCREASE OVER WATCH
AREA. FAVORABLE LOW LEVEL AND EFFECTIVE SHEAR WILL PROMOTE
SUPERCELLS CAPABLE OF DAMAGING WINDS...HAIL...AND THE POSSIBILITY OF
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
400. MEAN STORM MOTION VECTOR 25030.
...HARTSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Nov 10, 6:15 PM CST | Mesoscale Discussion | SPC | Bastrop, Bell, Blanco, Bosque, Brown, Burnet and 28 more | 90 min |
| Nov 10, 10:33 PM CST | Mesoscale Discussion | SPC | Austin, Bastrop, Bell, Blanco, Bosque, Brazoria and 52 more | 117 min |
| Nov 11, 1:23 AM CST | Mesoscale Discussion | SPC | Austin, Brazoria, Brazos, Burleson, Calhoun, Chambers and 24 more | 97 min |
| Nov 11, 1:25 AM CST | Mesoscale Discussion | SPC | Brown, Burnet, Coke, Coleman, Concho, Coryell and 15 more | 65 min |
| Nov 11, 10:21 AM CST | Mesoscale Discussion | SPC | Angelina, Brazos, Burleson, Grimes, Jasper, Lee and 14 more | 54 min |
| Nov 11, 1:06 PM CST | Mesoscale Discussion | SPC | Austin, Chambers, Fort Bend, Hardin, Harris, Jasper and 9 more | 54 min |
Nearby
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.