Alert archive / Texas / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 436

July 23, 201413 parishes in Louisiana; 15 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Jul 23, 2014, 6:29 PM CDT for 13 parishes in Louisiana; 15 counties in Texas. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 23, 2014, 6:29 PM CDT (23:29 UTC)
Expired
Jul 23, 2014, 11:00 PM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
0.5 in
Strongest gust expected
65 kt
All 28 counties

Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Union Parish, LA, Webster Parish, LA, Winn Parish, LA, Anderson County, TX, Cherokee County, TX, Freestone County, TX, Henderson County, TX, Houston County, TX, Kaufman County, TX, Leon County, TX, Limestone County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Rockwall County, TX, Rusk County, TX, Shelby County, TX, Van Zandt County, TX

The radar

The Shreveport radar (KSHV), 91 km from the middle of the area, began a volume at 23:31 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
5%
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
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 23, 6:52 PM CDTSevere Thunderstorm WarningSHVCaldwell, LaSalle38 min
Jul 23, 6:57 PM CDTSevere Thunderstorm WarningSHVClaiborne, Union48 min
Jul 23, 7:13 PM CDTSevere Thunderstorm WarningSHVBienville, Bossier, Caddo, Claiborne, De Soto, Red River and 1 more62 min
Jul 23, 7:21 PM CDTSevere Thunderstorm WarningSHVCherokee, Gregg, Harrison, Nacogdoches, Panola, Rusk and 4 more54 min
Jul 23, 7:36 PM CDTSevere Thunderstorm WarningFWDVan Zandt39 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

Shreveport, LA (KBAD), launched 12:00Z, 11.5 hours before the alert went out and 100 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, Shreveport, LA at 12:00Z on 2014-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 397 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, Shreveport, LA at 12:00Z on 2014-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 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
397 J/kg
Mixed-layer CIN
-100 J/kg
Mixed-layer LCL
1049 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 23, 6:06 PM CDTMesoscale DiscussionSPCBossier, Caddo, Claiborne, Union, Webster84 min
Jul 23, 3:01 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Delta, Fannin, Franklin and 6 more89 min
Jul 23, 4:04 PM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Collin, Delta, Fannin and 15 more5 hr

Nearby

Severe Thunderstorm Watches in Texas, 2014Severe Thunderstorm Watches in Louisiana, 2014Every severe thunderstorm watch in 2014

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.