Alert archive / Texas / Tornado Watches in 2007
Tornado Watch 255
The Storm Prediction Center issued this tornado watch at May 7, 2007, 7:32 PM CDT for 18 counties in Oklahoma; 21 counties in Texas. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 7, 2007, 7:32 PM CDT (00:32 UTC)
- Expired
- May 8, 2007, 3:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 39 counties
Atoka County, OK, Bryan County, OK, Carter County, OK, Choctaw County, OK, Coal County, OK, Garvin County, OK, Hughes County, OK, Jefferson County, OK, Johnston County, OK, Latimer County, OK, Love County, OK, Marshall County, OK, McCurtain County, OK, Murray County, OK, Pittsburg County, OK, Pontotoc County, OK, Pushmataha County, OK, Stephens County, OK, Camp County, TX, Clay County, TX, Collin County, TX, Cooke County, TX, Delta County, TX, Denton County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Jack County, TX, Lamar County, TX, Montague County, TX, Morris County, TX, Rains County, TX, Red River County, TX, Titus County, TX, Upshur County, TX, Wise County, TX, Wood County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 162 km from the middle of the area, began a volume at 00:33 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
- 20%
- Ten or more severe hail reports
- 50%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 7, 7:36 PM CDT | Flash Flood Warning | FWD | Cooke, Denton, Wise | 3 hr |
| May 7, 7:57 PM CDT | Severe Thunderstorm Warning | FWD | Cooke, Grayson | 63 min |
| May 7, 8:42 PM CDT | Severe Thunderstorm Warning | OUN | Bryan | 48 min |
| May 7, 8:58 PM CDT | Severe Thunderstorm Warning | FWD | Grayson | 77 min |
| May 7, 9:03 PM CDT | Tornado Warning | FWD | Grayson | 42 min |
| May 7, 9:05 PM CDT | Tornado Warning | OUN | Bryan | 25 min |
| May 7, 9:28 PM CDT | Severe Thunderstorm Warning | OUN | Bryan | 37 min |
| May 7, 9:33 PM CDT | Severe Thunderstorm Warning | TSA | Choctaw | 48 min |
| May 8, 2:32 AM CDT | Flash Flood Warning | FWD | Denton, 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, 0.5 hours before the alert went out and 141 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
- 2192 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 1136 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- 27 m²/s²
- 0-3 km storm-relative helicity
- 184 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 2.8
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 080035
SEL5
SPC WW 080035
OKZ000-TXZ000-080800-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 255
NWS STORM PREDICTION CENTER NORMAN OK
735 PM CDT MON MAY 7 2007
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
SOUTHERN AND EASTERN OKLAHOMA
NORTH CENTRAL AND NORTHEAST TEXAS
EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 735 PM UNTIL
300 AM CDT.
TORNADOES...HAIL TO 2 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 EITHER SIDE OF A LINE FROM 35 MILES EAST NORTHEAST OF PARIS
TEXAS TO 65 MILES WEST SOUTHWEST OF ARDMORE OKLAHOMA. 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 253...WW 254...
DISCUSSION...TSTMS ARE FORMING JUST DOWNSTREAM OF APPARENT MCV NEAR
FWD. THIS ACTIVITY IS DEVELOPING IN A DEEPLY MOIST ENVIRONMENT OF
MODERATE 0-6 KM SHEAR. LOW LEVEL DIRECTIONAL SHEAR IS ENHANCED JUST
NE OF MCV...WHERE NEAR-SFC FLOW REMAINS BACKED N OF WSW/ENE ORIENTED
OUTFLOW BOUNDARY ACROSS N TX. EXPECT STORMS TO INCREASE IN COVERAGE
AS LLJ NOCTURNALLY STRENGTHENS. EMBEDDED SUPERCELLS MAY POSE A
THREAT FOR TORNADOES...GIVEN UPSTREAM INFLOW ENVIRONMENT OF VERY
WARM/MOIST AIR...AND BACKED FLOW N OF OUTFLOW BOUNDARY.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 22025.
...CORFIDISPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 7, 7:15 PM CDT | Mesoscale Discussion | SPC | Atoka, Bryan, Carter, Choctaw, Johnston, Love and 1 more | 60 min |
| May 7, 9:45 PM CDT | Mesoscale Discussion | SPC | Atoka, Bryan, Carter, Choctaw, Coal, Garvin and 12 more | 60 min |
| May 8, 2:46 PM CDT | Mesoscale Discussion | SPC | Atoka, Bryan, Carter, Coal, Jefferson, Johnston and 4 more | 2 hr |
| May 8, 3:41 PM CDT | Severe Thunderstorm Watch | SPC | Comanche, Cotton, Jackson, Jefferson, Kiowa, Stephens and 1 more | 6 hr |
| May 8, 5:09 PM CDT | Mesoscale Discussion | SPC | Comanche, Cotton, Jackson, Jefferson, Kiowa, Stephens and 1 more | 96 min |
| May 8, 5:29 PM CDT | Tornado Watch | SPC | Caddo, Comanche, Cotton, Grady, Jackson, Jefferson and 3 more | 5 hr |
| May 7, 8:37 PM CDT | Severe Thunderstorm Watch | SPC | Andrews, Borden, Briscoe, Childress, Coke, Cottle and 38 more | 7 hr |
| May 7, 9:23 PM CDT | Mesoscale Discussion | SPC | Bandera, Dimmit, Edwards, Frio, Kerr, Kinney and 8 more | 67 min |
| May 7, 11:15 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Cochran, Crosby, Dawson, Dickens and 12 more | 60 min |
| May 7, 11:43 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Cochran, Crosby, Dawson, Dickens and 17 more | 62 min |
| May 8, 11:19 AM CDT | Mesoscale Discussion | SPC | Borden, Callahan, Coke, Crane, Ector, Fisher and 20 more | 116 min |
| May 8, 12:01 PM CDT | Tornado Watch | SPC | Andrews, Borden, Brewster, Coke, Crane, Crockett and 27 more | 7 hr |
| May 8, 2:44 PM CDT | Mesoscale Discussion | SPC | Coke, Crockett, Fisher, Glasscock, Irion, Mitchell and 6 more | 91 min |
| May 8, 6:13 PM CDT | Mesoscale Discussion | SPC | Bandera, Edwards, Kerr, Kinney, Medina, Real and 2 more | 62 min |
| May 8, 6:58 PM CDT | Severe Thunderstorm Watch | SPC | Bandera, Dimmit, Edwards, Gillespie, Kendall, Kerr and 8 more | 4 hr |
Nearby
Tornado Watches in Texas, 2007Tornado Watches in Oklahoma, 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.