Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 13, NWS Austin/San Antonio, TX

March 23, 20217 counties in Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Mar 23, 2021, 12:35 AM CDT for 7 counties in Texas. It was in force for 55 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
Mar 23, 2021, 12:35 AM CDT (05:35 UTC)
Expired
Mar 23, 2021, 1:30 AM CDT
In force
55 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Bandera County, TX, Bexar County, TX, Blanco County, TX, Comal County, TX, Hays County, TX, Kendall County, TX, Kerr County, TX

The radar

The Austin/San Antonio radar (KEWX), 49 km from the middle of the area, began a volume at 05:37 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
Mar 23, 12:56 AM CDTHAIL 1.754 Ssw Twin Sisters, TXGOLF BALL SIZED HAIL CALLED IN ON THE NORTH SIDE OF SPRING BRANCH.
Mar 23, 1:04 AM CDTHAIL 11 E Boerne, TX
Mar 23, 1:04 AM CDTTORNADOCanyon Lake, TXAN NWS STORM SURVEY FOUND AN EF1 TORNADO WITH ESTIMATED PEAK WINDS OF 100 MPH ON THE WESTERN SHORE OF CANYON LAKE.
Mar 23, 1:05 AM CDTHAIL 1.753 Nw Canyon Lake, TXNUMEROUS REPORTS OF QUARTER TO GOLF BALL SIZED HAIL AROUND CANYON LAKE.
Mar 23, 1:07 AM CDTHAIL 11 Wsw Boerne, TXTWO DIFFERENT SOCIAL MEDIA REPORTS OF QUARTER SIZED HAIL IN BOERNE.

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
Mar 22, 6:05 PM CDTSevere Thunderstorm WatchSPC7 hr
Mar 22, 11:10 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 5.6 hours before the alert went out and 237 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 2021-03-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1091 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Del Rio, TX at 00:00Z on 2021-03-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 204 square meters per square second.1939587897117136Sfc1 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
1091 J/kg
Mixed-layer CIN
-138 J/kg
Mixed-layer LCL
1422 m above ground
0-6 km bulk shear
86 kt
0-1 km storm-relative helicity
204 m²/s²
0-3 km storm-relative helicity
225 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.6

Open this sounding in Storm Lab

The text

As transmitted.

084 
WUUS54 KEWX 230535
SVREWX
TXC019-029-031-091-209-259-265-230630-
/O.NEW.KEWX.SV.W.0013.210323T0535Z-210323T0630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
1235 AM CDT Tue Mar 23 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Northeastern Bandera County in south central Texas...
  Southeastern Kerr County in south central Texas...
  West central Hays County in south central Texas...
  Southwestern Blanco County in south central Texas...
  Kendall County in south central Texas...
  Northwestern Bexar County in south central Texas...
  Comal County in south central Texas...

* Until 130 AM CDT.

* At 1235 AM CDT, a severe thunderstorm was located over Walnut
  Grove, or 7 miles north of Boerne, moving east at 35 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...
  New Braunfels, Schertz, Universal City, Boerne, Selma, Wimberley,
  Blanco, Canyon Lake Dam, Canyon Lake, Fair Oaks Ranch, Bulverde,
  Garden Ridge, Woodcreek, Walnut Grove, Guadalupe River State Park,
  Kendalia, Smithson Valley, Sisterdale, Kreutzberg and Spring
  Branch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9802 2962 9824 2960 9831 2957 9831
      2975 9885 2978 9910 3014 9863 3014 9859
      3017 9859 3024 9850
TIME...MOT...LOC 0535Z 289DEG 32KT 2989 9875 

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

EW
2 follow-up statements
520 
WWUS54 KEWX 230553
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
1253 AM CDT Tue Mar 23 2021

TXC019-265-230602-
/O.CAN.KEWX.SV.W.0013.000000T0000Z-210323T0630Z/
Bandera TX-Kerr TX-
1253 AM CDT Tue Mar 23 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN BANDERA AND
SOUTHEASTERN KERR COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 200 AM CDT for
south central Texas. A Severe Thunderstorm Watch also remains in
effect until 400 AM CDT for south central Texas.

LAT...LON 3004 9802 2962 9824 2960 9831 2957 9831
      2978 9892 2987 9892 3014 9859 3017 9859
      3024 9850
TIME...MOT...LOC 0552Z 289DEG 32KT 2984 9858 

$$

TXC029-031-091-209-259-230630-
/O.CON.KEWX.SV.W.0013.000000T0000Z-210323T0630Z/
Hays TX-Blanco TX-Kendall TX-Bexar TX-Comal TX-
1253 AM CDT Tue Mar 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 AM CDT
FOR WEST CENTRAL HAYS...SOUTHWESTERN BLANCO...KENDALL...NORTH CENTRAL
BEXAR AND COMAL COUNTIES...

At 1252 AM CDT, a severe thunderstorm was located over Bergheim, or 9
miles east of Boerne, moving east at 35 mph.

HAZARD...70 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
New Braunfels, Schertz, Universal City, Boerne, Selma, Wimberley,
Blanco, Canyon Lake Dam, Canyon Lake, Fair Oaks Ranch, Bulverde,
Garden Ridge, Woodcreek, Walnut Grove, Guadalupe River State Park,
Kendalia, Smithson Valley, Sisterdale, Kreutzberg and Spring Branch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9802 2962 9824 2960 9831 2957 9831
      2978 9892 2987 9892 3014 9859 3017 9859
      3024 9850
TIME...MOT...LOC 0552Z 289DEG 32KT 2984 9858 

HAIL...1.25IN
WIND...70MPH
 
$$

EW
538 
WWUS54 KEWX 230611
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
111 AM CDT Tue Mar 23 2021

TXC029-031-091-209-259-230630-
/O.CON.KEWX.SV.W.0013.000000T0000Z-210323T0630Z/
Hays TX-Blanco TX-Kendall TX-Bexar TX-Comal TX-
111 AM CDT Tue Mar 23 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 AM CDT
FOR WEST CENTRAL HAYS...SOUTH CENTRAL BLANCO...SOUTHEASTERN
KENDALL...NORTH CENTRAL BEXAR AND COMAL COUNTIES...

At 110 AM CDT, a severe thunderstorm was located near Smithson
Valley, or 13 miles southwest of Canyon Lake Dam, moving east at 35
mph.

HAZARD...Golf ball size hail and 70 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect 
         considerable tree damage. Wind damage is also likely to 
         mobile homes, roofs, and outbuildings.

Locations impacted include...
New Braunfels, Schertz, Universal City, Boerne, Selma, Wimberley,
Canyon Lake Dam, Canyon Lake, Fair Oaks Ranch, Bulverde, Garden
Ridge, Woodcreek, Guadalupe River State Park, Smithson Valley, Spring
Branch, Payton, Timberwood Park, Fischer, Twin Sisters and Bergheim.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3004 9802 2962 9824 2960 9831 2957 9831
      2973 9875 2989 9865 2995 9847 3007 9837
      3016 9830
TIME...MOT...LOC 0610Z 289DEG 32KT 2979 9840 

HAIL...1.75IN
WIND...70MPH
 
$$

EW

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 22, 8:32 PM CDTSevere Thunderstorm WarningEWXBurnet, Llano58 min
Mar 22, 9:02 PM CDTSpecial Weather StatementEWXBlanco, Gillespie, Llano43 min
Mar 22, 9:14 PM CDTSevere Thunderstorm WarningEWXBurnet, Llano, Williamson61 min
Mar 22, 9:16 PM CDTSevere Thunderstorm WarningEWXBlanco, Burnet, Gillespie, Llano59 min
Mar 22, 9:58 PM CDTSevere Thunderstorm WarningEWXBurnet, Williamson62 min
Mar 22, 10:05 PM CDTSevere Thunderstorm WarningEWXBandera, Blanco, Comal, Kendall, Kerr55 min
Mar 22, 10:11 PM CDTSevere Thunderstorm WarningEWXBlanco, Burnet, Gillespie, Hays, Travis64 min
Mar 22, 10:26 PM CDTTornado WarningEWXWilliamson27 min
Mar 22, 10:34 PM CDTSpecial Weather StatementEWXGillespie41 min
Mar 22, 10:56 PM CDTSevere Thunderstorm WarningEWXWilliamson41 min
Mar 22, 10:57 PM CDTSpecial Weather StatementEWXComal, Hays, Kendall48 min
Mar 22, 11:02 PM CDTSpecial Weather StatementEWXTravis58 min
Mar 22, 11:31 PM CDTSevere Thunderstorm WarningEWXBandera, Edwards, Medina, Real, Uvalde59 min
Mar 22, 11:34 PM CDTSpecial Weather StatementEWXBandera, Kendall, Kerr41 min
Mar 22, 11:44 PM CDTSevere Thunderstorm WarningEWXBandera, Gillespie, Kendall, Kerr, Medina61 min
Mar 22, 11:55 PM CDTSpecial Weather StatementEWXBastrop65 min
Mar 23, 12:25 AM CDTSpecial Weather StatementEWXLee65 min
Mar 23, 12:25 AM CDTSevere Thunderstorm WarningEWXBandera, Medina, Uvalde65 min
Mar 23, 1:06 AM CDTTornado WarningEWXComal, Guadalupe, Hays24 min
Mar 23, 1:13 AM CDTSevere Thunderstorm WarningEWXBandera, Bexar, Comal, Guadalupe, Kendall, Medina and 1 more62 min
Mar 23, 1:19 AM CDTSpecial Weather StatementEWXMedina41 min
Mar 23, 1:26 AM CDTSevere Thunderstorm WarningEWXBastrop, Caldwell, Comal, Gonzales, Guadalupe, Hays and 1 more64 min
Mar 23, 1:48 AM CDTSevere Thunderstorm WarningEWXAtascosa, Bexar, Frio, Medina34 min
Mar 23, 1:58 AM CDTSevere Thunderstorm WarningEWXGonzales, Guadalupe32 min
Mar 23, 2:13 AM CDTSevere Thunderstorm WarningEWXBexar, Gonzales, Guadalupe, Karnes, Wilson26 min
Mar 23, 2:16 AM CDTSevere Thunderstorm WarningEWXBastrop, Caldwell, Fayette, Gonzales, Guadalupe, Lavaca and 1 more59 min
Mar 23, 3:03 AM CDTSevere Thunderstorm WarningEWXFayette, Lavaca33 min
Mar 23, 3:43 AM CDTSpecial Weather StatementEWXDeWitt, Lavaca47 min
Mar 23, 4:07 AM CDTSevere Thunderstorm WarningEWXLavaca38 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.