Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 91, NWS Austin/San Antonio, TX

May 30, 2012Gillespie County, Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 30, 2012, 10:18 PM CDT for Gillespie County, Llano County, Texas. It was in force for 43 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
May 30, 2012, 10:18 PM CDT (03:18 UTC)
Expired
May 30, 2012, 11:01 PM CDT
In force
43 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

Counties Gillespie County, TX, Llano County, TX

The radar

The Austin/San Antonio radar (KEWX), 118 km from the middle of the area, began a volume at 03:20 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
May 30, 5:11 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 3.3 hours before the alert went out and 218 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 2012-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2015 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 2012-05-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 33 square meters per square second.19395878Sfc1 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
2015 J/kg
Mixed-layer CIN
-184 J/kg
Mixed-layer LCL
2271 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
33 m²/s²
0-3 km storm-relative helicity
166 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

999 
WUUS54 KEWX 310318
SVREWX
TXC171-299-310415-
/O.NEW.KEWX.SV.W.0091.120531T0318Z-120531T0415Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1018 PM CDT WED MAY 30 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GILLESPIE COUNTY...
  SOUTHWESTERN LLANO COUNTY...

* UNTIL 1115 PM CDT.

* AT 1015 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 8 MILES NORTH OF
  DOSS...OR 14 MILES SOUTH OF MASON...AND MOVING SOUTHEAST AT 25 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE CHERRY SPRING...ENCHANTED
  ROCK STATION...HILLTOP...CRABAPPLE...TIVYDALE...ROCKY HILL AND
  FREDERICKSBURG.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A VERY DANGEROUS SEVERE THUNDERSTORMS WITH A HISTORY OF 
PRODUCING TORNADOES. A TORNADO WATCH REMAINS IN EFFECT UNTIL 
MIDNIGHT CDT THURSDAY MORNING FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3027 9860 3014 9914 3051 9927 3050 9898
      3061 9897 3061 9896
TIME...MOT...LOC 0318Z 320DEG 23KT 3054 9915

$$
2 follow-up statements
110 
WWUS54 KEWX 310347
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1047 PM CDT WED MAY 30 2012

TXC171-299-310415-
/O.CON.KEWX.SV.W.0091.000000T0000Z-120531T0415Z/
GILLESPIE TX-LLANO TX-
1047 PM CDT WED MAY 30 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1115 PM CDT
FOR SOUTHWESTERN LLANO AND NORTHEASTERN GILLESPIE COUNTIES...

AT 1041 PM CDT...NWS METEOROLOGISTS CONTINUED TO DETECT A SEVERE 
THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH 
AND NICKEL SIZE HAIL. THIS STORM WAS LOCATED NEAR CHERRY SPRING...OR 
16 MILES NORTHWEST OF FREDERICKSBURG...MOVING SOUTHEAST AT 25 MPH.

OTHER LOCATIONS IN THE WARNING AREA INCLUDE HILLTOP AND CRABAPPLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT UNTIL MIDNIGHT CDT THURSDAY MORNING
FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3027 9860 3023 9897 3051 9920 3050 9898
      3061 9897 3061 9896
TIME...MOT...LOC 0346Z 312DEG 21KT 3046 9897

$$
958 
WWUS54 KEWX 310401
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1101 PM CDT WED MAY 30 2012

TXC171-299-310411-
/O.CAN.KEWX.SV.W.0091.000000T0000Z-120531T0415Z/
GILLESPIE TX-LLANO TX-
1101 PM CDT WED MAY 30 2012

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN LLANO AND
NORTHEASTERN GILLESPIE COUNTIES IS CANCELLED...

THE THUNDERSTORM THAT MOVED FROM MASON COUNTY INTO NORTHERN 
GILLESPIE AND SOUTHWESTERN LLANO COUNTY HAS WEAKENED TO BELOW SEVERE 
LEVELS. 

LAT...LON 3027 9860 3023 9897 3051 9920 3050 9898
      3061 9897 3061 9896
TIME...MOT...LOC 0401Z 312DEG 21KT 3040 9889

$$

Nearby

Severe Thunderstorm Warnings in Texas, 2012Every severe thunderstorm warning 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.