Alert archive / Oklahoma / Tornado Watches in 2007

Tornado Watch 251

May 6, 200719 counties in Oklahoma; 5 counties in Texas

The Storm Prediction Center issued this tornado watch at May 6, 2007, 11:54 PM CDT for 19 counties in Oklahoma; 5 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 6, 2007, 11:54 PM CDT (04:54 UTC)
Expired
May 7, 2007, 5:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
50 kt
All 24 counties

Caddo County, OK, Canadian County, OK, Cleveland County, OK, Comanche County, OK, Cotton County, OK, Garvin County, OK, Grady County, OK, Jackson County, OK, Jefferson County, OK, Kay County, OK, Kingfisher County, OK, Kiowa County, OK, Logan County, OK, McClain County, OK, Noble County, OK, Oklahoma County, OK, Stephens County, OK, Tillman County, OK, Washita County, OK, Archer County, TX, Baylor County, TX, Clay County, TX, Wichita County, TX, Wilbarger County, TX

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
10%
Ten or more severe wind reports
20%
One or more gusts of 65 knots or more
5%
Ten or more severe hail reports
20%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
30%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 6, 11:54 PM CDTFlash Flood WarningOUNBeckham, Custer, Washita4 hr
May 7, 12:57 AM CDTSevere Thunderstorm WarningOUNCotton48 min
May 7, 1:13 AM CDTSevere Thunderstorm WarningOUNComanche, Stephens47 min
May 7, 1:49 AM CDTSevere Thunderstorm WarningOUNCaddo, Grady41 min
May 7, 2:02 AM CDTSevere Thunderstorm WarningOUNStephens32 min
May 7, 2:19 AM CDTSevere Thunderstorm WarningOUNCleveland, McClain, Oklahoma41 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

Norman, OK (KOUN), launched 00:00Z, 4.9 hours before the alert went out and 88 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, Norman, OK at 00:00Z on 2007-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2453 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, Norman, OK at 00:00Z on 2007-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 square meters per square second.193958Sfc1 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
2453 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
905 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
236 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 070454
SEL1  
SPC WW 070454
OKZ000-TXZ000-071000-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 251
NWS STORM PREDICTION CENTER NORMAN OK
1155 PM CDT SUN MAY 6 2007

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

       WESTERN AND CENTRAL OKLAHOMA
       WESTERN NORTH TEXAS

EFFECTIVE THIS SUNDAY NIGHT AND MONDAY MORNING FROM 1155 PM UNTIL
500 AM CDT.

TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 60 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTH OF ALTUS
OKLAHOMA TO CHANDLER OKLAHOMA.  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...CONTINUE...WW 248...WW 249...WW 250...

DISCUSSION...SCTD SHOWERS/TSTMS HAVE DEVELOPED IN THE PAST HOUR IN
MOIST/UNSTABLE ENVIRONMENT ALONG THE I-44 CORRIDOR.  WEAKLY
CONFLUENT NEAR-SFC FLOW...RICH MOISTURE...PROXIMITY OF 50 KT LLJ AND
DISCRETE NATURE OF CONVECTION SUGGEST POTENTIAL FOR ISOLATED
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 50 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.
MEAN STORM MOTION VECTOR 21030.


...CORFIDI

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 8:55 PM CDTMesoscale DiscussionSPCCherokee, Craig, Creek, Delaware, Hughes, McIntosh and 14 more65 min
May 6, 9:07 PM CDTTornado WatchSPCCherokee, Coal, Craig, Creek, Delaware, Hughes and 19 more6 hr
May 6, 9:26 PM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Custer and 10 more64 min
May 6, 11:04 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Caddo, Canadian, Carter, Choctaw and 17 more56 min
May 6, 11:34 PM CDTMesoscale DiscussionSPCCherokee, Coal, Craig, Creek, Delaware, Hughes and 19 more56 min
May 7, 1:59 AM CDTMesoscale DiscussionSPCCherokee, Coal, Craig, Creek, Delaware, Hughes and 18 more91 min
May 7, 4:30 AM CDTMesoscale DiscussionSPCCaddo, Canadian, Cleveland, Comanche, Cotton, Garvin and 8 more30 min
May 7, 10:29 AM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Coal, Johnston and 3 more2 hr
May 7, 10:51 AM CDTTornado WatchSPCAtoka, Bryan, Carter, Choctaw, Coal, Garvin and 10 more5 hr
May 6, 7:04 PM CDTMesoscale DiscussionSPCCrockett, Irion, Reagan, Terrell, Upton56 min
May 6, 7:55 PM CDTTornado WatchSPCCoke, Coleman, Concho, Crockett, Glasscock, Howard and 13 more6 hr
May 6, 10:20 PM CDTMesoscale DiscussionSPCConcho, Irion, Reagan, Tom Green55 min
May 7, 1:14 PM CDTMesoscale DiscussionSPCCrockett, Edwards, Irion, Kimble, Kinney, Menard and 6 more61 min
May 7, 1:59 PM CDTMesoscale DiscussionSPCCrockett, Edwards, Irion, Kimble, Kinney, Menard and 6 more61 min
May 7, 5:38 PM CDTMesoscale DiscussionSPCDimmit, Kinney, Maverick, Uvalde, Zavala67 min
May 7, 5:59 PM CDTTornado WatchSPCBandera, Dimmit, Edwards, Frio, Kerr, Kinney and 8 more8 hr
May 7, 6:19 PM CDTMesoscale DiscussionSPCBrewster, Crane, Ector, Jeff Davis, Midland, Pecos and 7 more86 min
May 7, 6:42 PM CDTTornado WatchSPCBrewster, Jeff Davis, Pecos, Presidio, Reeves, Terrell5 hr

Nearby

Tornado Watches in Oklahoma, 2007Tornado Watches in Texas, 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.