Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 62, NWS Austin/San Antonio, TX

May 6, 2012Burnet County, Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 6, 2012, 6:54 PM CDT for Burnet County, Llano County, Texas. It was in force for 51 min. 5 reports 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
May 6, 2012, 6:54 PM CDT (23:54 UTC)
Expired
May 6, 2012, 7:45 PM CDT
In force
51 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

Counties Burnet County, TX, Llano County, TX

The radar

The Ft Hood radar (KGRK), 119 km from the middle of the area, began a volume at 23:57 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
May 6, 7:00 PM CDTHAIL 23 Nw Llano, TXEGG SIZE HAIL.
May 6, 7:15 PM CDTHAIL 13 Ene Llano, TXONE INCH SIZE HAIL.
May 6, 7:23 PM CDTHAIL 11 N Llano, TXONE INCH SIZE HAIL AND VERY STRONG WINDS.
May 6, 7:38 PM CDTHAIL 1.752 W Llano, TXQUARTER TO GOLFBALL SIZE SIZE HAIL.
May 6, 7:46 PM CDTHAIL 1.753 Se Llano, TXGOLFBALL SIZE HAIL IN DRIFTS.

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

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 11.9 hours before the alert went out and 255 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, Fort Worth, TX at 12:00Z on 2012-05-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1528 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, Fort Worth, TX at 12:00Z on 2012-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 11 square meters per square second.1939Sfc1 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
1528 J/kg
Mixed-layer CIN
-387 J/kg
Mixed-layer LCL
1140 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
11 m²/s²
0-3 km storm-relative helicity
71 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

076 
WUUS54 KEWX 062354
SVREWX
TXC053-299-070045-
/O.NEW.KEWX.SV.W.0062.120506T2354Z-120507T0045Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
654 PM CDT SUN MAY 6 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WEST CENTRAL BURNET COUNTY...
  NORTHERN LLANO COUNTY...

* UNTIL 745 PM CDT.

* AT 654 PM CDT...NWS METEOROLOGISTS HAVE DETECTED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  LLANO...AND MOVING EAST AT 10 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE BABY HEAD...LONE GROVE...
  GAINESVILLE...STOLZ...BLUFFTON...TOW AND BUCHANAN DAM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM WITH A HISTORY OF PRODUCING GOLFBALL SIZE 
HAIL AND VERY HEAVY RAINFALL UP TO 2 INCHES. IF YOU ARE IN ITS 
PATH...PREPARE IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE 
HAIL...AND DEADLY CLOUD TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD 
MOVE TO A SHELTER...PREFERABLY INSIDE A STRONG BUILDING BUT AWAY 
FROM WINDOWS.

&&

LAT...LON 3093 9832 3063 9856 3078 9893 3092 9896
TIME...MOT...LOC 2354Z 272DEG 7KT 3081 9868

$$
2 follow-up statements
516 
WWUS54 KEWX 070019
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
719 PM CDT SUN MAY 6 2012

TXC053-299-070045-
/O.CON.KEWX.SV.W.0062.000000T0000Z-120507T0045Z/
LLANO TX-BURNET TX-
719 PM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM CDT
FOR WEST CENTRAL BURNET AND NORTHERN LLANO COUNTIES...

AT 717 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 NEAR LLANO...
MOVING SOUTH AT 15 MPH.

LAT...LON 3093 9832 3063 9856 3078 9893 3092 9896
TIME...MOT...LOC 0018Z 349DEG 12KT 3075 9864

$$
584 
WWUS54 KEWX 070025
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
725 PM CDT SUN MAY 6 2012

TXC053-299-070045-
/O.CON.KEWX.SV.W.0062.000000T0000Z-120507T0045Z/
LLANO TX-BURNET TX-
725 PM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM CDT
FOR WEST CENTRAL BURNET AND NORTHERN LLANO COUNTIES...

AT 722 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 NEAR LLANO...
MOVING SOUTH AT 15 MPH.

THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

HAIL UP TO ONE INCH IN DIAMETER HAS BEEN REPORTED 3 MILES EAST OF 
LLANO WITH THIS STORM. IF YOU ARE IN THE PATH OF THE STORM...TAKE 
IMMEDIATE ACTION TO PROTECT LIFE AND PROPERTY.

&&

LAT...LON 3093 9832 3063 9856 3078 9893 3092 9896
TIME...MOT...LOC 0024Z 349DEG 12KT 3073 9864

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 5, 8:33 PM CDTRiver Flood WarningEWXVal Verde19 days
May 6, 12:55 AM CDTAreal Flood AdvisoryEWXTravis, Williamson2 hr
May 6, 3:26 AM CDTSevere Thunderstorm WarningEWXBexar, Comal34 min
May 6, 4:11 AM CDTAreal Flood AdvisoryEWXBexar3 hr
May 6, 6:12 PM CDTSevere Thunderstorm WarningEWXBurnet, Llano63 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.