Alert archive / Texas / Tornado Warnings in 2011

Tornado Warning 10, NWS Austin/San Antonio, TX

May 21, 2011Burnet County, Williamson County, Texas

NWS Austin/San Antonio, TX issued this tornado warning at May 21, 2011, 7:59 PM CDT for Burnet County, Williamson County, Texas. It was in force for 31 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 21, 2011, 7:59 PM CDT (00:59 UTC)
Expired: May 21, 2011, 8:30 PM CDT
In force: 31 min
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon

Counties Burnet County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 49 km from the middle of the area, began a volume at 01:02 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.

Issued	Product	Office	Lasted
May 21, 1:45 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 1.0 hours before the alert went out and 233 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3908 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 978 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 116 m²/s²
0-3 km storm-relative helicity: 188 m²/s²
Significant tornado parameter: 3.2
Supercell composite: 16.6

Open this sounding in Storm Lab

The text

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

991 
WFUS54 KEWX 220059
TOREWX
TXC053-491-220130-
/O.NEW.KEWX.TO.W.0010.110522T0059Z-110522T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
759 PM CDT SAT MAY 21 2011

THE NATIONAL WEATHER SERVICE IN AUSTIN SAN ANTONIO HAS ISSUED A

* TORNADO WARNING FOR...
  EAST CENTRAL BURNET COUNTY...
  NORTHWESTERN WILLIAMSON COUNTY...

* UNTIL 830 PM CDT.

* AT 757 PM CDT...NWS METEOROLOGISTS HAVE DETECTED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR MAHOMET...OR ABOUT
  NEAR BERTRAM...MOVING EAST AT 20 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE ANDICE AND FLORENCE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS ON THE LOWEST FLOOR OF A
BUILDING IN AN INTERIOR HALLWAY...BATHROOM...OR CLOSET. COVER
YOURSELF WITH BLANKETS...PILLOWS OR EVEN A MATTRESS FOR BETTER
PROTECTION.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM CDT
SATURDAY EVENING FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3085 9778 3071 9782 3076 9806 3084 9801
TIME...MOT...LOC 0059Z 270DEG 16KT 3078 9798

$$

1 follow-up statement

062 
WWUS54 KEWX 220115
SVSEWX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
815 PM CDT SAT MAY 21 2011

TXC053-491-220130-
/O.CON.KEWX.TO.W.0010.000000T0000Z-110522T0130Z/
BURNET TX-WILLIAMSON TX-
815 PM CDT SAT MAY 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
NORTHWESTERN WILLIAMSON AND EAST CENTRAL BURNET COUNTIES...

AT 811 PM CDT...NWS METEOROLOGISTS CONTINUED TO DETECT A TORNADO. 
THIS TORNADO WAS LOCATED NEAR MAHOMET...OR 9 MILES EAST OF BERTRAM...
MOVING EAST AT 20 MPH.

RESIDENTS NEAR ANDICE SHOULD TAKE COVER NOW!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS ON THE LOWEST FLOOR OF A
BUILDING IN AN INTERIOR HALLWAY...BATHROOM...OR CLOSET. COVER
YOURSELF WITH BLANKETS...PILLOWS OR EVEN A MATTRESS FOR BETTER
PROTECTION.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM CDT
SATURDAY EVENING FOR SOUTH CENTRAL TEXAS.

&&

LAT...LON 3082 9779 3072 9782 3076 9800 3083 9794
TIME...MOT...LOC 0114Z 277DEG 16KT 3077 9790

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 7:10 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Travis, Williamson	50 min
May 21, 7:27 PM CDT	Tornado Warning	EWX	Burnet, Williamson	33 min
May 21, 7:44 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Williamson	46 min
May 21, 7:50 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	40 min
May 21, 8:08 PM CDT	Areal Flood Advisory	EWX	Burnet, Williamson	112 min
May 21, 8:11 PM CDT	Tornado Warning	EWX	Burnet, Llano	34 min
May 21, 8:27 PM CDT	Severe Thunderstorm Warning	EWX	Williamson	48 min
May 21, 8:27 PM CDT	Tornado Warning	EWX	Williamson	33 min
May 21, 8:32 PM CDT	Severe Thunderstorm Warning	EWX	Burnet	43 min
May 21, 8:44 PM CDT	Tornado Warning	EWX	Burnet	31 min
May 21, 8:59 PM CDT	Tornado Warning	EWX	Williamson	31 min
May 21, 9:14 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Williamson	46 min

Nearby

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