Alert archive / Texas / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 127

April 2, 20124 states

The Storm Prediction Center issued this severe thunderstorm watch at Apr 2, 2012, 12:41 PM CDT for 4 states. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 2, 2012, 12:41 PM CDT (17:41 UTC)
Expired
Apr 2, 2012, 7:00 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 46 counties

Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Drew County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pike County, AR, Sevier County, AR, Union County, AR, Claiborne Parish, LA, Lincoln Parish, LA, Ouachita Parish, LA, Union Parish, LA, Webster Parish, LA, Choctaw County, OK, McCurtain County, OK, Pushmataha County, OK, Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Delta County, TX, Fannin County, TX, Franklin County, TX, Henderson County, TX, Hopkins County, TX, Hunt County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Navarro County, TX, Rains County, TX, Red River County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 130 km from the middle of the area, began a volume at 17:42 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
5%
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
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 2, 1:30 PM CDTSevere Thunderstorm WarningSHVBienville, Bossier, Caddo, Webster45 min
Apr 2, 1:46 PM CDTSevere Thunderstorm WarningFWDHenderson, Van Zandt59 min
Apr 2, 1:52 PM CDTSevere Thunderstorm WarningSHVBienville, Caldwell, Claiborne, Jackson, Lincoln, Ouachita and 2 more38 min
Apr 2, 2:13 PM CDTSevere Thunderstorm WarningSHVColumbia, Lafayette, Miller62 min
Apr 2, 2:22 PM CDTSevere Thunderstorm WarningSHVUnion53 min
Apr 2, 2:22 PM CDTSevere Thunderstorm WarningFWDRains, Van Zandt31 min
Apr 2, 2:24 PM CDTSevere Thunderstorm WarningFWDHopkins66 min
Apr 2, 2:38 PM CDTSevere Thunderstorm WarningSHVFranklin, Red River, Titus67 min
Apr 2, 2:58 PM CDTSevere Thunderstorm WarningSHVColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 2 more62 min
Apr 2, 3:00 PM CDTSevere Thunderstorm WarningFWDDelta45 min
Apr 2, 3:08 PM CDTSevere Thunderstorm WarningSHVUnion37 min
Apr 2, 3:09 PM CDTSevere Thunderstorm WarningLZKBradley, Calhoun, Clark, Ouachita66 min
Apr 2, 3:45 PM CDTSevere Thunderstorm WarningSHVMcCurtain60 min
Apr 2, 3:59 PM CDTSevere Thunderstorm WarningSHVHempstead, Howard, Nevada, Sevier49 min
Apr 2, 4:09 PM CDTSevere Thunderstorm WarningLZKMontgomery, Pike, Polk51 min
Apr 2, 4:30 PM CDTSevere Thunderstorm WarningLZKDesha, Drew, Lincoln30 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 (KSHV), launched 12:00Z, 5.7 hours before the alert went out and 131 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 2012-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1679 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 2012-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -91 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
1679 J/kg
Mixed-layer CIN
-73 J/kg
Mixed-layer LCL
558 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-91 m²/s²
0-3 km storm-relative helicity
4 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 2, 12:15 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 17 more90 min
Apr 2, 12:50 PM CDTSevere Thunderstorm WatchSPCAshley, Chicot7 hr
Apr 2, 3:18 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Clark, Cleveland, Columbia and 28 more117 min
Apr 2, 3:23 PM CDTMesoscale DiscussionSPCAshley, Chicot2 hr
Apr 2, 3:49 PM CDTSevere Thunderstorm WatchSPCArkansas, Conway, Crawford, Desha, Faulkner, Franklin and 19 more4 hr
Apr 2, 5:58 PM CDTMesoscale DiscussionSPCArkansas, Clark, Cleveland, Conway, Dallas, Desha and 23 more62 min
Apr 2, 9:57 AM CDTMesoscale DiscussionSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 27 more63 min
Apr 2, 10:10 AM CDTSevere Thunderstorm WatchSPCAcadia, Allen, Ascension, Assumption, Avoyelles, Beauregard and 31 more7 hr
Apr 2, 5:36 PM CDTMesoscale DiscussionSPCOrleans, Saint Bernard, Saint Tammany54 min
Apr 2, 3:00 PM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 16 more2 hr
Apr 2, 3:37 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Comanche and 16 more7 hr
Apr 2, 5:16 AM CDTMesoscale DiscussionSPCAustin, Brazoria, Chambers, Colorado, Fayette, Fort Bend and 13 more2 hr
Apr 2, 6:51 PM CDTMesoscale DiscussionSPCArcher, Baylor, Brown, Callahan, Clay, Coleman and 17 more54 min

Nearby

Severe Thunderstorm Watches in Texas, 2012Severe Thunderstorm Watches in Arkansas, 2012Severe Thunderstorm Watches in Louisiana, 2012Every severe thunderstorm watch in 2012

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.