Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 63, NWS Austin/San Antonio, TX

May 6, 2012Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 6, 2012, 7:33 PM CDT for Llano County, Texas. It was in force for 42 min. 2 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, 7:33 PM CDT (00:33 UTC)
Expired
May 6, 2012, 8:15 PM CDT
In force
42 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

County Llano County, TX

The radar

The Austin/San Antonio radar (KEWX), 117 km from the middle of the area, began a volume at 00:36 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, 7:38 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

Del Rio, TX (KDRT), launched 00:00Z, 0.6 hours before the alert went out and 253 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 2012-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1964 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 2012-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -28 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
1964 J/kg
Mixed-layer CIN
-158 J/kg
Mixed-layer LCL
2142 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
-28 m²/s²
0-3 km storm-relative helicity
13 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.

839 
WUUS54 KEWX 070033
SVREWX
TXC299-070115-
/O.NEW.KEWX.SV.W.0063.120507T0033Z-120507T0115Z/

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

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL LLANO COUNTY...

* UNTIL 815 PM CDT.

* AT 731 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 NEAR LLANO...AND
  MOVING SOUTH AT 15 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE OXFORD.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3051 9853 3052 9881 3077 9877 3075 9857
TIME...MOT...LOC 0033Z 357DEG 12KT 3068 9867

$$
1 follow-up statement
937 
WWUS54 KEWX 070049
SVSEWX

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

TXC299-070115-
/O.CON.KEWX.SV.W.0063.000000T0000Z-120507T0115Z/
LLANO TX-
749 PM CDT SUN MAY 6 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTH CENTRAL LLANO COUNTY...

AT 746 PM CDT...NWS METEOROLOGISTS CONTINUED TO DETECT A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND DAMAGING
WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR OXFORD...OR 8
MILES SOUTH OF LLANO...MOVING SOUTH AT 15 MPH.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

QUARTER TO GOLF BALL SIZED HAIL HAS BEEN REPORTED 2 MILES WEST OF 
LLANO WITH THIS STORM. IF YOU ARE IN THE PATH OF THE STORM...TAKE 
IMMEDIATE ACTION TO PROTECT LIFE AND PROPERTY.

&&

LAT...LON 3071 9878 3070 9856 3051 9853 3052 9881
TIME...MOT...LOC 0048Z 357DEG 12KT 3063 9867

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 6, 7:09 PM CDTAreal Flood AdvisoryEWXLlano111 min
May 7, 3:28 AM CDTFlash Flood WatchEWXBandera, Bexar, Blanco, Burnet, Comal, Edwards and 12 more37 hr
May 7, 4:47 PM CDTSevere Thunderstorm WarningEWXLlano58 min
May 7, 5:10 PM CDTTornado WarningEWXLlano35 min
May 7, 5:23 PM CDTSevere Thunderstorm WarningEWXLlano37 min
May 7, 5:32 PM CDTTornado WarningEWXGillespie, Llano28 min
May 7, 5:43 PM CDTTornado WarningEWXLlano32 min
May 7, 5:57 PM CDTSevere Thunderstorm WarningEWXBlanco, Burnet, Gillespie, Llano63 min
May 7, 6:08 PM CDTAreal Flood AdvisoryEWXLlano112 min
May 7, 6:49 PM CDTSevere Thunderstorm WarningEWXBlanco, Gillespie, Kendall56 min
May 7, 6:51 PM CDTAreal Flood AdvisoryEWXGillespie2 hr

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.