Alert archive / Texas / Severe Thunderstorm Watches in 2015

Severe Thunderstorm Watch 98

April 24, 201511 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Apr 24, 2015, 3:01 AM CDT for 11 counties in Texas. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 24, 2015, 3:01 AM CDT (08:01 UTC)
Expired
Apr 24, 2015, 7:24 AM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt

Counties Atascosa County, TX, Dimmit County, TX, Frio County, TX, La Salle County, TX, Live Oak County, TX, Maverick County, TX, McMullen County, TX, Medina County, TX, Uvalde County, TX, Webb County, TX, Zavala County, TX

The radar

The Laughlin AFB radar (KDFX), 119 km from the middle of the area, began a volume at 08:03 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
20%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
20%
One or more gusts of 65 knots or more
5%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
60%

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Del Rio, TX (KDLF), launched 00:00Z, 8.0 hours before the alert went out and 169 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, Del Rio, TX at 00:00Z on 2015-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1325 joules per kilogram.LCLEL10008507005003002001001 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, Del Rio, TX at 00:00Z on 2015-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.1939587897Sfc1 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
1325 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1694 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
214 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.8

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 23, 9:34 PM CDTMesoscale DiscussionSPCBandera, Dimmit, Edwards, Frio, Jim Hogg, Kinney and 10 more56 min
Apr 24, 2:36 AM CDTMesoscale DiscussionSPCDimmit, La Salle, McMullen, Webb, Zavala84 min
Apr 24, 5:41 AM CDTMesoscale DiscussionSPCAtascosa, Bandera, Dimmit, Duval, Edwards, Frio and 10 more94 min
Apr 24, 10:29 AM CDTMesoscale DiscussionSPCHardin, Jasper, Liberty, Newton, Orange, Tyler91 min
Apr 24, 11:12 AM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coke, Coleman, Collin and 43 more2 hr
Apr 24, 11:53 AM CDTMesoscale DiscussionSPCHardin, Jefferson, Newton, Orange97 min
Apr 24, 12:18 PM CDTTornado WatchSPCJasper, Newton, Orange5 hr
Apr 24, 12:56 PM CDTMesoscale DiscussionSPCChildress, Collingsworth, Cottle, Crosby, Dickens, Foard and 3 more94 min
Apr 24, 2:10 PM CDTTornado WatchSPCAnderson, Bell, Bosque, Brown, Callahan, Coke and 52 more8 hr
Apr 24, 3:58 PM CDTMesoscale DiscussionSPCAngelina, Camp, Cass, Cherokee, Gregg, Harrison and 16 more92 min
Apr 24, 4:45 PM CDTTornado WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 20 more5 hr
Apr 24, 4:56 PM CDTMesoscale DiscussionSPCAtascosa, Dimmit, Duval, Frio, Jim Hogg, Kinney and 9 more94 min
Apr 24, 6:01 PM CDTMesoscale DiscussionSPCDallas, Ellis, Erath, Hood, Johnson, Kaufman and 3 more59 min
Apr 24, 6:53 PM CDTSevere Thunderstorm WatchSPCAtascosa, Bee, Brooks, Cameron, DeWitt, Dimmit and 19 more6 hr

Nearby

Severe Thunderstorm Watches in Texas, 2015Every severe thunderstorm watch in 2015

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.