Alert archive / Texas / Severe Thunderstorm Watches in 2009

Severe Thunderstorm Watch 752

October 1, 2009McCurtain County, Oklahoma; 47 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Oct 1, 2009, 3:50 PM CDT for McCurtain County, Oklahoma; 47 counties in Texas. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Oct 1, 2009, 3:50 PM CDT (20:50 UTC)
Expired
Oct 1, 2009, 11:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 48 counties

McCurtain County, OK, Anderson County, TX, Bell County, TX, Bosque County, TX, Camp County, TX, Cherokee County, TX, Collin County, TX, Cooke County, TX, Coryell County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Erath County, TX, Falls County, TX, Fannin County, TX, Franklin County, TX, Freestone County, TX, Grayson County, TX, Hamilton County, TX, Henderson County, TX, Hill County, TX, Hood County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Lampasas County, TX, Leon County, TX, Limestone County, TX, McLennan County, TX, Milam County, TX, Mills County, TX, Navarro County, TX, Parker County, TX, Rains County, TX, Red River County, TX, Robertson County, TX, Rockwall County, TX, Smith County, TX, Somervell County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wise County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 64 km from the middle of the area, began a volume at 20:50 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
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Oct 1, 4:08 PM CDTSevere Thunderstorm WarningFWDMills52 min
Oct 1, 4:20 PM CDTSevere Thunderstorm WarningFWDErath40 min
Oct 1, 4:22 PM CDTSevere Thunderstorm WarningFWDCooke38 min
Oct 1, 4:36 PM CDTSevere Thunderstorm WarningFWDDenton39 min
Oct 1, 4:42 PM CDTSevere Thunderstorm WarningFWDGrayson48 min
Oct 1, 4:45 PM CDTSevere Thunderstorm WarningFWDBosque, Hamilton31 min
Oct 1, 4:48 PM CDTSevere Thunderstorm WarningFWDCoryell, Lampasas57 min
Oct 1, 4:52 PM CDTSevere Thunderstorm WarningFWDDenton, Wise53 min
Oct 1, 4:56 PM CDTSevere Thunderstorm WarningFWDParker, Tarrant64 min
Oct 1, 5:08 PM CDTSevere Thunderstorm WarningFWDHood, Johnson67 min
Oct 1, 5:15 PM CDTSevere Thunderstorm WarningFWDDenton45 min
Oct 1, 5:39 PM CDTSevere Thunderstorm WarningFWDDallas, Denton, Tarrant66 min
Oct 1, 5:43 PM CDTSevere Thunderstorm WarningSHVMcCurtain62 min
Oct 1, 6:00 PM CDTSevere Thunderstorm WarningFWDCollin, Hunt45 min
Oct 1, 6:14 PM CDTSevere Thunderstorm WarningFWDCoryell, Lampasas46 min
Oct 1, 6:51 PM CDTSevere Thunderstorm WarningFWDCoryell, Lampasas39 min
Oct 1, 6:52 PM CDTSevere Thunderstorm WarningSHVMcCurtain53 min
Oct 1, 7:26 PM CDTSevere Thunderstorm WarningFWDBell20 min
Oct 1, 7:27 PM CDTSevere Thunderstorm WarningSHVBowie, Red River63 min
Oct 1, 7:32 PM CDTSevere Thunderstorm WarningFWDLampasas58 min
Oct 1, 8:08 PM CDTSevere Thunderstorm WarningFWDBosque, Hill40 min
Oct 1, 8:11 PM CDTSevere Thunderstorm WarningFWDBell, Coryell49 min
Oct 1, 8:33 PM CDTSevere Thunderstorm WarningFWDMcLennan57 min
Oct 1, 9:23 PM CDTSevere Thunderstorm WarningFWDFreestone, Limestone27 min
Oct 1, 9:25 PM CDTSevere Thunderstorm WarningFWDFalls, McLennan42 min
Oct 1, 10:45 PM CDTSevere Thunderstorm WarningFWDLeon34 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

Fort Worth, TX (KFWD), launched 12:00Z, 8.8 hours before the alert went out and 60 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 2009-10-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1985 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, Fort Worth, TX at 12:00Z on 2009-10-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 264 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
1985 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
530 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
264 m²/s²
0-3 km storm-relative helicity
410 m²/s²
Significant tornado parameter
2.0
Supercell composite
8.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Oct 1, 12:44 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more91 min
Oct 1, 1:16 PM CDTSevere Thunderstorm WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more6 hr
Oct 1, 5:12 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Cleburne, Conway, Crawford and 21 more93 min
Oct 1, 6:02 PM CDTMesoscale DiscussionSPCSevier58 min
Oct 1, 6:29 PM CDTSevere Thunderstorm WatchSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 21 more8 hr
Sep 30, 7:31 PM CDTMesoscale DiscussionSPCAlfalfa, Blaine, Custer, Dewey, Ellis, Harper and 5 more89 min
Oct 1, 2:17 PM CDTMesoscale DiscussionSPCBosque, Brown, Collin, Comanche, Coryell, Dallas and 27 more88 min

Nearby

Severe Thunderstorm Watches in Texas, 2009Severe Thunderstorm Watches in Oklahoma, 2009Every severe thunderstorm watch in 2009

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.