Alert archive / Texas / Tornado Warnings in 2011

Tornado Warning 1, NWS Austin/San Antonio, TX

April 21, 2011Val Verde County, Texas

NWS Austin/San Antonio, TX issued this tornado warning at Apr 21, 2011, 11:50 PM CDT for Val Verde County, Texas. It was in force for 26 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 21, 2011, 11:50 PM CDT (04:50 UTC)
Expired
Apr 22, 2011, 12:16 AM CDT
In force
26 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

County Val Verde County, TX

The radar

The Laughlin AFB radar (KDFX), 85 km from the middle of the area, began a volume at 04:53 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 was reported inside it

TimeReportWhereRemark
Apr 22, 12:01 AM CDTHAIL 0.258 Sse Comstock, TXPEA SIZE HAIL... SOME RAIN AND HIGH WINDS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 4.8 hours before the alert went out and 32 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.

632 
WFUS54 KEWX 220450
TOREWX
TXC465-220530-
/O.NEW.KEWX.TO.W.0001.110422T0450Z-110422T0530Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1150 PM CDT THU APR 21 2011

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* TORNADO WARNING FOR...
  VAL VERDE COUNTY...

* UNTIL 1230 AM CDT.

* AT 1148 PM CDT...NWS METEOROLOGISTS HAVE DETECTED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 12 MILES WEST OF ROUGH
  CANYON REC AREA...OR ABOUT 9 MILES SOUTH OF COMSTOCK...MOVING EAST
  AT 5 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE DEVILS SHORES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN A MOBILE HOME OR VEHICLE...GET OUT AND GO TO A STURDY
SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE NEAREST DITCH
OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 2962 10121 2964 10090 2946 10088 2951 10122
TIME...MOT...LOC 0451Z 275DEG 6KT 2955 10118

$$
1 follow-up statement
854 
WWUS54 KEWX 220516
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1216 AM CDT FRI APR 22 2011

TXC465-220525-
/O.CAN.KEWX.TO.W.0001.000000T0000Z-110422T0530Z/
VAL VERDE TX-
1216 AM CDT FRI APR 22 2011

...THE TORNADO WARNING FOR VAL VERDE COUNTY IS CANCELLED...

THE THUNDERSTORM THAT PROMPTED THE TORNADO WARNING IS WEAKENING 
RAPIDLY AND NO LONGER POSES A THREAT FOR TORNADOES. HAIL TO THE SIZE 
OF NICKELS AND WINDS IN EXCESS OF 55 MPH ARE STILL POSSIBLE FROM 
THIS THUNDERSTORM.

LAT...LON 2962 10121 2964 10090 2946 10088 2951 10122
TIME...MOT...LOC 0515Z 242DEG 13KT 2961 10106

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 7:54 PM CDTSevere Thunderstorm WarningEWXVal Verde36 min
Apr 21, 10:46 PM CDTSevere Thunderstorm WarningEWXVal Verde59 min
Apr 21, 11:42 PM CDTSevere Thunderstorm WarningEWXVal Verde37 min

Nearby

Tornado Warnings in Texas, 2011Every tornado warning in 2011Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.