Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 16, NWS Austin/San Antonio, TX

February 4, 2012Bexar County, Guadalupe County, Wilson County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Feb 4, 2012, 12:15 AM CST for Bexar County, Guadalupe County, Wilson County, Texas. It was in force for 45 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
Feb 4, 2012, 12:15 AM CST (06:15 UTC)
Expired
Feb 4, 2012, 1:00 AM CST
In force
45 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon

Counties Bexar County, TX, Guadalupe County, TX, Wilson County, TX

The radar

The Austin/San Antonio radar (KEWX), 29 km from the middle of the area, began a volume at 06:16 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 nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 6.3 hours before the alert went out and 209 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, Corpus Christi, TX at 00:00Z on 2012-02-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2376 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, Corpus Christi, TX at 00:00Z on 2012-02-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 99 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
2376 J/kg
Mixed-layer CIN
-24 J/kg
Mixed-layer LCL
706 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
145 m²/s²
Significant tornado parameter
1.2
Supercell composite
6.5

Open this sounding in Storm Lab

The text

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

627 
WUUS54 KEWX 040615
SVREWX
TXC029-187-493-040700-
/O.NEW.KEWX.SV.W.0016.120204T0615Z-120204T0700Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1215 AM CST SAT FEB 4 2012

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL BEXAR COUNTY...
  SOUTHWESTERN GUADALUPE COUNTY...
  NORTH CENTRAL WILSON COUNTY...

* UNTIL 100 AM CST.

* AT 1211 AM CST...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 ST.
  HEDWIG...OR 9 MILES SOUTH OF UNIVERSAL CITY...AND MOVING EAST AT 15
  MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE LA VERNIA AND NEW BERLIN.

VERY HEAVY RAINS WITH RAINFALL RATES OF 2 TO 4 INCHES CAN ALSO BE 
EXPECTED. 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. 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 2957 9807 2933 9805 2937 9831 2950 9831
TIME...MOT...LOC 0615Z 269DEG 12KT 2942 9825

$$
1 follow-up statement
191 
WWUS54 KEWX 040639
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1239 AM CST SAT FEB 4 2012

TXC029-187-493-040700-
/O.CON.KEWX.SV.W.0016.000000T0000Z-120204T0700Z/
GUADALUPE TX-WILSON TX-BEXAR TX-
1239 AM CST SAT FEB 4 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 100 AM CST
FOR EAST CENTRAL BEXAR...NORTH CENTRAL WILSON AND SOUTHWESTERN
GUADALUPE COUNTIES...

AT 1235 AM CST...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 ST. HEDWIG...
OR 11 MILES SOUTHEAST OF UNIVERSAL CITY...MOVING EAST AT 15 MPH. 
VERY HEAVY RAINS WITH RAINFALL RATES OF 1 TO 3 INCHES PER HOUR CAN 
ALSO BE EXPECTED. 

SOME LOCATIONS IN THE WARNING AREA INCLUDE LA VERNIA AND NEW BERLIN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. 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 2938 9828 2950 9824 2957 9807 2933 9805
TIME...MOT...LOC 0639Z 269DEG 12KT 2943 9818

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 3, 9:18 PM CSTAreal Flood AdvisoryEWXBexar2 hr
Feb 3, 9:45 PM CSTAreal Flood AdvisoryEWXWilliamson105 min
Feb 3, 10:02 PM CSTFlash Flood WarningEWXBexar118 min
Feb 3, 10:15 PM CSTSevere Thunderstorm WarningEWXBexar30 min
Feb 3, 10:36 PM CSTFlash Flood WarningEWXWilliamson114 min
Feb 3, 10:38 PM CSTSevere Thunderstorm WarningEWXBexar37 min
Feb 3, 10:51 PM CSTFlash Flood WarningEWXBexar3 hr
Feb 3, 11:15 PM CSTSevere Thunderstorm WarningEWXBexar, Guadalupe60 min
Feb 4, 12:57 AM CSTAreal Flood AdvisoryEWXBurnet2 hr
Feb 4, 1:07 AM CSTAreal Flood AdvisoryEWXHays, Travis113 min
Feb 4, 1:25 AM CSTFlash Flood WarningEWXTravis, Williamson3 hr
Feb 4, 1:54 AM CSTAreal Flood AdvisoryEWXBexar, Guadalupe, Wilson2 hr
Feb 4, 2:32 AM CSTAreal Flood AdvisoryEWXBandera, Medina118 min
Feb 4, 2:42 AM CSTFlash Flood WarningEWXHays, Travis3 hr
Feb 4, 3:11 AM CSTAreal Flood AdvisoryEWXBandera, Bexar, Medina109 min
Feb 4, 3:27 AM CSTAreal Flood AdvisoryEWXBastrop, Caldwell, Hays, Lee, Travis2 hr
Feb 4, 4:06 AM CSTAreal Flood AdvisoryEWXBexar, Comal, Guadalupe114 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.