Alert archive / Texas / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 21, NWS Austin/San Antonio, TX

April 21, 2011Val Verde County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 21, 2011, 7:54 PM CDT for Val Verde County, Texas. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Apr 21, 2011, 7:54 PM CDT (00:54 UTC)
Expired
Apr 21, 2011, 8:30 PM CDT
In force
36 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

County Val Verde County, TX

The radar

The Laughlin AFB radar (KDFX), 156 km from the middle of the area, began a volume at 00:58 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 21, 3:03 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 0.9 hours before the alert went out and 109 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 2011-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2280 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 00:00Z on 2011-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 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
2280 J/kg
Mixed-layer CIN
-76 J/kg
Mixed-layer LCL
2009 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
155 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.

844 
WUUS54 KEWX 220054
SVREWX
TXC465-220130-
/O.NEW.KEWX.SV.W.0021.110422T0054Z-110422T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
754 PM CDT THU APR 21 2011

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  VAL VERDE COUNTY...

* UNTIL 830 PM CDT.

* AT 754 PM CDT...NWS METEOROLOGISTS HAVE DETECTED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING
  WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 21 MILES WEST OF
  PANDALE...OR 27 MILES NORTHWEST OF LANGTRY...AND MOVING EAST 
  AT 30 MPH. THIS STORM PRODUCED A WIND GUST OF 58 MPH IN DRYDEN. 

* SOME LOCATIONS IN THE WARNING INCLUDE HACKBERRY CROSSING AND 
PANDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT
THURSDAY EVENING FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3027 10177 3028 10175 3029 10132 3002 10129
      3001 10131 2998 10130 2998 10176 3000 10177
TIME...MOT...LOC 0051Z 268DEG 26KT 3010 10187

$$
1 follow-up statement
384 
WWUS54 KEWX 220112
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
812 PM CDT THU APR 21 2011

TXC465-220130-
/O.CON.KEWX.SV.W.0021.000000T0000Z-110422T0130Z/
VAL VERDE TX-
812 PM CDT THU APR 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR VAL VERDE COUNTY...

AT 812 PM CDT...NWS METEOROLOGISTS CONTINUED TO DETECT A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND DAMAGING
WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 9 MILES SOUTHWEST
OF HACKBERRY CROSSING...OR 22 MILES NORTHWEST OF LANGTRY...MOVING 
EAST AT 30 MPH. THIS STORM HAS HAD A HISTORY OF PRODUCING WIND GUSTS 
UP TO 60 MPH AND NICKEL SIZE HAIL.

SOME LOCATIONS IN THE WARNING AREA INCLUDE PANDALE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT
THURSDAY EVENING FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3027 10177 3028 10175 3029 10132 3002 10129
      3001 10131 2998 10130 2998 10176 3000 10177
TIME...MOT...LOC 0108Z 268DEG 26KT 3010 10173

$$

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 21, 10:46 PM CDTSevere Thunderstorm WarningEWXVal Verde59 min
Apr 21, 11:42 PM CDTSevere Thunderstorm WarningEWXVal Verde37 min
Apr 21, 11:50 PM CDTTornado WarningEWXVal Verde26 min

Nearby

Severe Thunderstorm Warnings in Texas, 2011Every severe thunderstorm warning in 2011

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.