Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 122, NWS Austin/San Antonio, TX

May 11, 2021Blanco County, Kendall County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 11, 2021, 7:31 PM CDT for Blanco County, Kendall County, Texas. It was in force for 25 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 11, 2021, 7:31 PM CDT (00:31 UTC)
Expired
May 11, 2021, 7:56 PM CDT
In force
25 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Blanco County, TX, Kendall County, TX

The radar

The Austin/San Antonio radar (KEWX), 55 km from the middle of the area, began a volume at 00:35 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.

IssuedProductOfficeLasted
May 11, 3:41 PM CDTSevere Thunderstorm WatchSPC10 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 0.5 hours before the alert went out and 244 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 2021-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1860 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, Del Rio, TX at 00:00Z on 2021-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 142 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
1860 J/kg
Mixed-layer CIN
-67 J/kg
Mixed-layer LCL
838 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
142 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
1.5
Supercell composite
5.4

Open this sounding in Storm Lab

The text

As transmitted.

096 
WUUS54 KEWX 120031
SVREWX
TXC031-259-120115-
/O.NEW.KEWX.SV.W.0122.210512T0031Z-210512T0115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
731 PM CDT Tue May 11 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Southwestern Blanco County in south central Texas...
  Northeastern Kendall County in south central Texas...

* Until 815 PM CDT.

* At 730 PM CDT, a severe thunderstorm was located near Kendalia, or
  11 miles southwest of Blanco, moving east at 25 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Blanco, Twin Sisters and Kendalia. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3018 9833 3004 9830 2996 9839 2992 9862
      3003 9866
TIME...MOT...LOC 0030Z 251DEG 22KT 3000 9858 

HAIL...1.00IN
WIND...<50MPH
 
$$
3 follow-up statements
582 
WWUS54 KEWX 120043
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
743 PM CDT Tue May 11 2021

TXC031-259-120115-
/O.CON.KEWX.SV.W.0122.000000T0000Z-210512T0115Z/
Blanco TX-Kendall TX-
743 PM CDT Tue May 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTHWESTERN BLANCO AND NORTHEASTERN KENDALL COUNTIES...

At 742 PM CDT, a severe thunderstorm was located near Flugrath, or
near Blanco, moving northeast at 25 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Blanco, Twin Sisters and Kendalia. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3018 9833 3004 9830 2996 9839 2995 9851
      3004 9861
TIME...MOT...LOC 0042Z 240DEG 22KT 3005 9851 

HAIL...1.00IN
WIND...<50MPH
 
$$

PLATT
689 
WWUS54 KEWX 120053
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
753 PM CDT Tue May 11 2021

TXC259-120103-
/O.CAN.KEWX.SV.W.0122.000000T0000Z-210512T0115Z/
Kendall TX-
753 PM CDT Tue May 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN KENDALL COUNTY 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 1000 PM CDT for
south central Texas.

LAT...LON 3018 9833 3004 9830 2996 9839 2996 9843
      3008 9853
TIME...MOT...LOC 0053Z 244DEG 18KT 3008 9847 

$$

TXC031-120115-
/O.CON.KEWX.SV.W.0122.000000T0000Z-210512T0115Z/
Blanco TX-
753 PM CDT Tue May 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 815 PM CDT
FOR SOUTHWESTERN BLANCO COUNTY...

At 753 PM CDT, a severe thunderstorm was located near Blanco, moving
northeast at 20 mph.

HAZARD...Quarter size hail.

SOURCE...Radar indicated.

IMPACT...Damage to vehicles is expected.

Locations impacted include...
Blanco and Twin Sisters. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3018 9833 3004 9830 2996 9839 2996 9843
      3008 9853
TIME...MOT...LOC 0053Z 244DEG 18KT 3008 9847 

HAIL...1.00IN
WIND...<50MPH
 
$$

PLATT
408 
WWUS54 KEWX 120056
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
756 PM CDT Tue May 11 2021

TXC031-120106-
/O.CAN.KEWX.SV.W.0122.000000T0000Z-210512T0115Z/
Blanco TX-
756 PM CDT Tue May 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHWESTERN BLANCO COUNTY 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 and
heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
south central Texas.

LAT...LON 3018 9833 3004 9830 2996 9839 2996 9843
      3008 9853
TIME...MOT...LOC 0055Z 251DEG 22KT 3009 9845 

$$

PLATT

The office that day

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

IssuedProductOfficeCountiesLasted
May 11, 7:07 PM CDTSpecial Weather StatementEWXComal, Kendall38 min
May 11, 7:10 PM CDTAreal Flood AdvisoryEWXDimmit, Frio, Zavala3 hr
May 11, 7:15 PM CDTAreal Flood AdvisoryEWXBandera, Bexar, Comal, Kendall, Medina3 hr
May 11, 7:24 PM CDTSpecial Weather StatementEWXBlanco51 min
May 11, 7:34 PM CDTSpecial Weather StatementEWXLavaca41 min
May 11, 8:10 PM CDTSpecial Weather StatementEWXBlanco50 min
May 11, 8:37 PM CDTAreal Flood AdvisoryEWXAtascosa3 hr
May 11, 8:43 PM CDTSpecial Weather StatementEWXTravis47 min
May 11, 8:48 PM CDTSevere Thunderstorm WarningEWXTravis26 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.