Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 53, NWS Austin/San Antonio, TX

April 23, 2021Bexar County, Comal County, Guadalupe County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 23, 2021, 6:45 PM CDT for Bexar County, Comal County, Guadalupe County, Texas. It was in force for 45 min. 3 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
Apr 23, 2021, 6:45 PM CDT (23:45 UTC)
Expired
Apr 23, 2021, 7:30 PM CDT
In force
45 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Bexar County, TX, Comal County, TX, Guadalupe County, TX

The radar

The Austin/San Antonio radar (KEWX), 40 km from the middle of the area, began a volume at 23:46 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
Apr 23, 7:03 PM CDTHAIL 0.5Alamo Heights, TXPUBLIC REPORT OF NUMEROUS HAIL STONES OF AT LEAST PEA SIZE, WITH SEVERAL HALF INCH SIZED HAIL STONES.
Apr 23, 7:08 PM CDTHAIL 13 Nw San Antonio, TXTWITTER PICTURE OF HAIL UP TO QUARTER SIZE.
Apr 23, 7:12 PM CDTHAIL 11 Wsw San Antonio, TXREPORT OF QUARTER SIZE HAIL AT PINKERTONS BBQ IN DOWNTOWN SAN ANTONIO.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 23, 12:37 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 12:00Z, 11.8 hours before the alert went out and 213 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 12:00Z on 2021-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1041 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 12:00Z on 2021-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 149 square meters per square second.1939587897Sfc1 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
1041 J/kg
Mixed-layer CIN
-53 J/kg
Mixed-layer LCL
520 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
149 m²/s²
0-3 km storm-relative helicity
150 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.1

Open this sounding in Storm Lab

The text

As transmitted.

196 
WUUS54 KEWX 232345
SVREWX
TXC029-091-187-240045-
/O.NEW.KEWX.SV.W.0053.210423T2345Z-210424T0045Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
645 PM CDT Fri Apr 23 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Southwestern Guadalupe County in south central Texas...
  Central Bexar County in south central Texas...
  South central Comal County in south central Texas...

* Until 745 PM CDT.

* At 644 PM CDT, a severe thunderstorm was located over San Antonio,
  moving east at 30 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* Locations impacted include...
  San Antonio, New Braunfels, Schertz, Cibolo, Universal City, Live
  Oak, Selma, San Antonio Int Airport, Randolph AFB, Leon Valley,
  Kirby, Alamo Heights, Windcrest, Terrell Hills, Garden Ridge,
  Hollywood Park, Olmos Park, St. Hedwig, China Grove and Marion.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Large hail, damaging winds, and continuous cloud to ground lightning
are occurring with this storm. Move indoors immediately. Lightning is
one of nature's leading killers. Remember, if you can hear thunder,
you are close enough to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2936 9861 2949 9865 2977 9823 2939 9794
      2938 9812 2944 9814 2938 9819
TIME...MOT...LOC 2344Z 256DEG 24KT 2944 9854 

HAIL...1.00IN
WIND...60MPH
 
$$

BRADY
2 follow-up statements
663 
WWUS54 KEWX 240010
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
710 PM CDT Fri Apr 23 2021

TXC029-091-187-240045-
/O.CON.KEWX.SV.W.0053.000000T0000Z-210424T0045Z/
Guadalupe TX-Bexar TX-Comal TX-
710 PM CDT Fri Apr 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 745 PM CDT
FOR SOUTHWESTERN GUADALUPE...NORTHEASTERN BEXAR AND SOUTH CENTRAL
COMAL COUNTIES...

At 710 PM CDT, a severe thunderstorm was located near Terrell Hills,
or near San Antonio, moving east at 15 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Public.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

Locations impacted include...
San Antonio, New Braunfels, Schertz, Cibolo, Universal City, Live
Oak, Selma, San Antonio Int Airport, Randolph AFB, Kirby, Alamo
Heights, Windcrest, Terrell Hills, Garden Ridge, Olmos Park, St.
Hedwig, China Grove, Marion, Santa Clara and New Berlin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 2936 9853 2953 9851 2973 9821 2944 9798
      2939 9794 2938 9812 2944 9814 2938 9819
TIME...MOT...LOC 0010Z 276DEG 13KT 2942 9844 

HAIL...1.00IN
WIND...60MPH
 
$$

BRADY
613 
WWUS54 KEWX 240030 RRA
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
730 PM CDT Fri Apr 23 2021

TXC029-091-187-240040-
/O.CAN.KEWX.SV.W.0053.000000T0000Z-210424T0045Z/
Guadalupe TX-Bexar TX-Comal TX-
730 PM CDT Fri Apr 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN GUADALUPE...
NORTHEASTERN BEXAR AND SOUTH CENTRAL COMAL COUNTIES IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning has been cancelled.  However small hail, gusty
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central Texas.

LAT...LON 2936 9853 2953 9851 2973 9821 2944 9798
      2939 9794 2938 9812 2944 9814 2938 9819
TIME...MOT...LOC 0028Z 256DEG 24KT 2945 9829 

$$

BRADY

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 23, 12:19 PM CDTSpecial Weather StatementEWXComal41 min
Apr 23, 12:59 PM CDTSpecial Weather StatementEWXHays31 min
Apr 23, 1:17 PM CDTSevere Thunderstorm WarningEWXCaldwell, Guadalupe23 min
Apr 23, 1:31 PM CDTAreal Flood AdvisoryEWXCaldwell, Guadalupe3 hr
Apr 23, 1:43 PM CDTSevere Thunderstorm WarningEWXBastrop, Travis25 min
Apr 23, 2:03 PM CDTAreal Flood AdvisoryEWXBastrop, Travis3 hr
Apr 23, 3:29 PM CDTAreal Flood AdvisoryEWXBastrop, Lee3 hr
Apr 23, 4:15 PM CDTSpecial Weather StatementEWXMaverick30 min
Apr 23, 4:39 PM CDTSevere Thunderstorm WarningEWXMaverick, Zavala51 min
Apr 23, 5:25 PM CDTSpecial Weather StatementEWXZavala50 min
Apr 23, 6:05 PM CDTSpecial Weather StatementEWXFrio55 min
Apr 23, 6:29 PM CDTSpecial Weather StatementEWXBexar61 min
Apr 23, 6:52 PM CDTSevere Thunderstorm WarningEWXAtascosa, Frio53 min
Apr 23, 6:59 PM CDTSpecial Weather StatementEWXAtascosa61 min

Nearby

Severe Thunderstorm Warnings in Texas, 2021Every severe thunderstorm warning in 2021

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.