Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 134, NWS Austin/San Antonio, TX

May 18, 20214 counties in Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 18, 2021, 3:40 PM CDT for 4 counties in Texas. It was in force for 65 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 18, 2021, 3:40 PM CDT (20:40 UTC)
Expired
May 18, 2021, 4:45 PM CDT
In force
65 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Caldwell County, TX, Comal County, TX, Hays County, TX, Travis County, TX

The radar

The Austin/San Antonio radar (KEWX), 36 km from the middle of the area, began a volume at 20:44 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 18, 4:09 PM CDTHAIL 11 Sse Kyle, TXQUARTER HAIL REPORTED IN KYLE WITH HEAVY RAINFALL.
May 18, 4:20 PM CDTTSTM WND DMG3 Sse Buda, TXREPORTS OF DAMAGE INCLUDING A FEW TREES DOWN AND A TRAMPOLINE THROWN AS WELL AS SEVERAL VIDEOS OF STRONG WINDS FROM THE BUDA AREA SHARED ON LOCAL MEDIAS SOCIAL MEDIA. TIME ESTIMATED VIA RADAR.

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
May 18, 2:29 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 12:00Z, 8.7 hours before the alert went out and 252 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 2021-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 12 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 2021-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -66 square meters per square second.193958Sfc1 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
12 J/kg
Mixed-layer CIN
-595 J/kg
Mixed-layer LCL
1962 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
-66 m²/s²
0-3 km storm-relative helicity
-43 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted.

951 
WUUS54 KEWX 182040
SVREWX
TXC055-091-209-453-182145-
/O.NEW.KEWX.SV.W.0134.210518T2040Z-210518T2145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
340 PM CDT Tue May 18 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Northwestern Caldwell County in south central Texas...
  Central Hays County in south central Texas...
  South central Travis County in south central Texas...
  East central Comal County in south central Texas...

* Until 445 PM CDT.

* At 339 PM CDT, severe thunderstorms were located along a line
  extending from near Driftwood to near Zorn, moving east at 25 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...
  Austin, San Marcos, Kyle, Buda, Lockhart, Wimberley, Austin
  Bergstrom Int Airport, Woodcreek, Martindale, Uhland, Mustang
  Ridge, Niederwald, Onion Creek, Shady Hollow, Manchaca, Mountain
  City, San Leanna, Hays, Creedmoor and Maha.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2986 9783 2985 9786 2985 9788 2975 9800
      2981 9802 2980 9809 3009 9813 3021 9762
TIME...MOT...LOC 2039Z 247DEG 23KT 3008 9802 2976 9798 

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

MO
4 follow-up statements
251 
WWUS54 KEWX 182049
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
349 PM CDT Tue May 18 2021

TXC055-091-209-453-182145-
/O.CON.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Caldwell TX-Hays TX-Travis TX-Comal TX-
349 PM CDT Tue May 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR NORTHWESTERN CALDWELL...CENTRAL HAYS...SOUTH CENTRAL TRAVIS AND
EAST CENTRAL COMAL COUNTIES...

At 349 PM CDT, severe thunderstorms were located along a line
extending from near Wimberley to San Marcos, moving northeast at 20
mph.

HAZARD...60 mph wind gusts and half dollar size hail.

SOURCE...Radar indicated.

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

Locations impacted include...
Austin, San Marcos, Kyle, Buda, Lockhart, Wimberley, Austin Bergstrom
Int Airport, Woodcreek, Martindale, Uhland, Mustang Ridge,
Niederwald, Onion Creek, Shady Hollow, Manchaca, Mountain City, San
Leanna, Hays, Creedmoor and Maha.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2986 9783 2985 9786 2985 9788 2975 9800
      2981 9802 2980 9809 3009 9813 3021 9762
TIME...MOT...LOC 2049Z 241DEG 18KT 3004 9802 2984 9792 

HAIL...1.25IN
WIND...60MPH
 
$$

MO
228 
WWUS54 KEWX 182108
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
408 PM CDT Tue May 18 2021

TXC091-182117-
/O.CAN.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Comal TX-
408 PM CDT Tue May 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL COMAL COUNTY IS
CANCELLED...

The storms which prompted the warning have moved east and out of the 
warned area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2986 9783 2985 9786 2985 9788 2978 9796
      3011 9806 3021 9762
TIME...MOT...LOC 2107Z 249DEG 27KT 3008 9791 2989 9776 

$$

TXC055-209-453-182145-
/O.CON.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Caldwell TX-Hays TX-Travis TX-
408 PM CDT Tue May 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR NORTHWESTERN CALDWELL...SOUTHEASTERN HAYS AND SOUTH CENTRAL
TRAVIS COUNTIES...

At 407 PM CDT, severe thunderstorms were located along a line
extending from near Buda to near Lockhart, 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...
Austin, San Marcos, Kyle, Buda, Lockhart, Austin Bergstrom Int
Airport, Martindale, Uhland, Mustang Ridge, Niederwald, Onion Creek,
Shady Hollow, Manchaca, Mountain City, San Leanna, Hays, Creedmoor,
Maha, Maxwell and Reedville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2986 9783 2985 9786 2985 9788 2978 9796
      3011 9806 3021 9762
TIME...MOT...LOC 2107Z 249DEG 27KT 3008 9791 2989 9776 

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

MO
684 
WWUS54 KEWX 182120
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
420 PM CDT Tue May 18 2021

TXC055-209-453-182145-
/O.CON.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Caldwell TX-Hays TX-Travis TX-
420 PM CDT Tue May 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR NORTHWESTERN CALDWELL...EAST CENTRAL HAYS AND SOUTH CENTRAL
TRAVIS COUNTIES...

At 419 PM CDT, severe thunderstorms were located along a line
extending from Onion Creek to Lockhart, 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...
Austin, San Marcos, Kyle, Buda, Lockhart, Austin Bergstrom Int
Airport, Martindale, Uhland, Mustang Ridge, Niederwald, Onion Creek,
Shady Hollow, Manchaca, Mountain City, San Leanna, Hays, Creedmoor,
Maha, Maxwell and Reedville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2986 9783 2985 9786 3014 9793 3021 9762
TIME...MOT...LOC 2119Z 252DEG 30KT 3014 9777 2989 9767 

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

MO
995 
WWUS54 KEWX 182133
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
433 PM CDT Tue May 18 2021

TXC209-182143-
/O.CAN.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Hays TX-
433 PM CDT Tue May 18 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL HAYS COUNTY IS
CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2988 9767 2988 9768 3001 9772 3003 9771
      3004 9773 3017 9778 3021 9762
TIME...MOT...LOC 2133Z 247DEG 23KT 3017 9768 2992 9758 

$$

TXC055-453-182145-
/O.CON.KEWX.SV.W.0134.000000T0000Z-210518T2145Z/
Caldwell TX-Travis TX-
433 PM CDT Tue May 18 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR NORTH CENTRAL CALDWELL AND SOUTH CENTRAL TRAVIS COUNTIES...

At 433 PM CDT, severe thunderstorms were located along a line
extending from Austin Bergstrom Int Airport to 6 miles northeast of
Lockhart, moving northeast at 25 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...
Austin, Lockhart, Austin Bergstrom Int Airport, Mustang Ridge,
Niederwald, Creedmoor, Maha, Pilot Knob, Lytton Springs, Mendoza,
McKinney Falls State Park, Dale and Del Valle.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 900 PM CDT for south central
Texas.

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

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. These storms may cause serious injury and significant
property damage.

&&

LAT...LON 3011 9760 3007 9765 3001 9758 2990 9756
      2988 9767 2988 9768 3001 9772 3003 9771
      3004 9773 3017 9778 3021 9762
TIME...MOT...LOC 2133Z 247DEG 23KT 3017 9768 2992 9758 

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

MO

The office that day

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

IssuedProductOfficeCountiesLasted
May 17, 7:14 PM CDTSevere Thunderstorm WarningEWXDimmit26 min
May 17, 7:46 PM CDTSpecial Weather StatementEWXDimmit44 min
May 17, 8:44 PM CDTSpecial Weather StatementEWXDimmit46 min
May 17, 9:36 PM CDTAreal Flood AdvisoryEWXDimmit, Zavala3 hr
May 17, 9:40 PM CDTSpecial Weather StatementEWXDimmit50 min
May 17, 10:10 PM CDTSpecial Weather StatementEWXFrio50 min
May 17, 10:39 PM CDTAreal Flood AdvisoryEWXDimmit, Frio, Zavala2 hr
May 17, 10:47 PM CDTSpecial Weather StatementEWXDimmit28 min
May 18, 9:56 AM CDTSpecial Weather StatementEWXReal49 min
May 18, 10:29 AM CDTSpecial Weather StatementEWXKerr46 min
May 18, 11:35 AM CDTSpecial Weather StatementEWXReal55 min
May 18, 11:58 AM CDTAreal Flood AdvisoryEWXEdwards, Kerr, Real, Val Verde5 hr
May 18, 12:54 PM CDTSpecial Weather StatementEWXBandera, Gillespie, Kendall51 min
May 18, 1:29 PM CDTSpecial Weather StatementEWXBlanco, Kendall46 min
May 18, 1:51 PM CDTSevere Thunderstorm WarningEWXBexar, Blanco, Comal, Kendall54 min
May 18, 2:01 PM CDTAreal Flood AdvisoryEWXBandera, Bexar, Comal, Kendall, Medina3 hr
May 18, 2:38 PM CDTSpecial Weather StatementEWXComal, Hays67 min
May 18, 2:46 PM CDTAreal Flood AdvisoryEWXBexar, Comal3 hr
May 18, 2:46 PM CDTSevere Thunderstorm WarningEWXComal, Hays59 min
May 18, 3:04 PM CDTSpecial Weather StatementEWXWilson41 min
May 18, 3:35 PM CDTSevere Thunderstorm WarningEWXCaldwell, Comal, Guadalupe55 min
May 18, 3:36 PM CDTAreal Flood AdvisoryEWXBexar, Caldwell, Comal, Guadalupe, Hays, Wilson3 hr
May 18, 3:59 PM CDTFlash Flood Warning Considerable damage threatEWXComal3 hr
May 18, 3:59 PM CDTSpecial Weather StatementEWXGonzales46 min
May 18, 4:24 PM CDTSevere Thunderstorm WarningEWXCaldwell, Gonzales, Guadalupe66 min
May 18, 4:27 PM CDTSevere Thunderstorm WarningEWXBastrop, Caldwell, Fayette, Gonzales, Lee, Travis63 min
May 18, 4:39 PM CDTSevere Thunderstorm WarningEWXFayette, Gonzales, Lavaca66 min
May 18, 4:48 PM CDTTornado WarningEWXLavaca27 min
May 18, 5:03 PM CDTAreal Flood AdvisoryEWXFayette, Gonzales, Lavaca3 hr
May 18, 5:15 PM CDTSpecial Weather StatementEWXWilson45 min
May 18, 5:21 PM CDTFlash Flood Warning Considerable damage threatEWXCaldwell, Gonzales, Guadalupe3 hr
May 18, 5:28 PM CDTAreal Flood AdvisoryEWXFrio3 hr
May 18, 5:29 PM CDTSpecial Weather StatementEWXFrio46 min
May 18, 5:31 PM CDTSpecial Weather StatementEWXLee44 min
May 18, 5:35 PM CDTSpecial Weather StatementEWXGonzales40 min
May 18, 5:39 PM CDTSpecial Weather StatementEWXFayette51 min
May 18, 5:42 PM CDTSevere Thunderstorm WarningEWXAtascosa, Frio24 min
May 18, 6:06 PM CDTAreal Flood AdvisoryEWXBastrop, Lee3 hr
May 18, 6:14 PM CDTTornado WarningEWXFayette31 min
May 18, 6:26 PM CDTTornado WarningEWXFayette34 min
May 18, 6:39 PM CDTTornado WarningEWXLavaca51 min
May 18, 6:41 PM CDTTornado Warning Tornado observedEWXFayette34 min
May 18, 6:44 PM CDTFlash Flood Warning Considerable damage threatEWXFayette, Gonzales, Lavaca8 hr
May 18, 6:53 PM CDTAreal Flood AdvisoryEWXDeWitt, Gonzales, Karnes, Lavaca, Wilson3 hr

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.