Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 32, NWS Austin/San Antonio, TX

April 12, 2021Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 12, 2021, 7:00 PM CDT for Llano County, Texas. It was in force for 60 min. 9 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 12, 2021, 7:00 PM CDT (00:00 UTC)
Expired
Apr 12, 2021, 8:00 PM CDT
In force
60 min
Issued by
NWS Austin/San Antonio, TX
Area
Storm-based polygon
Hail
2.75 in
Wind
60.0 mph

County Llano County, TX

The radar

The Ft Hood radar (KGRK), 124 km from the middle of the area, began a volume at 00:01 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 12, 7:05 PM CDTHAIL 1.757 W Valley Spring, TXGOLFBALL SIZE HAIL 4 MILES SOUTHEAST OF PONTOTOC ON COUNTY ROAD 405. 3 INCHES OF HAIL ACCUMULATION ON THE GROUND.
Apr 12, 7:35 PM CDTHAIL 2.755 Wnw Llano, TXBASEBALL SIZE HAIL 5 MILES WNW OF LLANO.
Apr 12, 7:38 PM CDTHAIL 37 W Llano, TX3 INCH HAIL REPORTED 7 MILES WEST OF LLANO. HAIL STOPPED AT 7:45 PM.
Apr 12, 7:41 PM CDTHAIL 1.758 S Valley Spring, TXLARGEST HAILSTONE AT THIS LOCATION WAS GOLFBALL WITH UP TO QUARTER SIZE HAIL STILL FALLING.
Apr 12, 7:43 PM CDTHAIL 2.5Llano, TXPICTURE OF MEASURED TENNIS BALL SIZE HAIL.
Apr 12, 7:45 PM CDTHAIL 1.75Llano, TX
Apr 12, 7:47 PM CDTHAIL 21 Nnw Llano, TX
Apr 12, 7:49 PM CDTHAIL 2.756 S Valley Spring, TXVEHICLE DAMAGE WITH WINDOWS BROKEN DUE TO BASEBALL SIZE HAIL.
Apr 12, 7:54 PM CDTHAIL 1.752 Se Llano, TXGOLFBALL SIZE HAIL VIA SOCIAL MEDIA.

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 12, 3:51 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 00:00Z, 0.0 hours before the alert went out and 258 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 2021-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2255 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 2021-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 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
2255 J/kg
Mixed-layer CIN
-208 J/kg
Mixed-layer LCL
1434 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
206 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.6

Open this sounding in Storm Lab

The text

As transmitted.

097 
WUUS54 KEWX 130000
SVREWX
TXC299-130100-
/O.NEW.KEWX.SV.W.0032.210413T0000Z-210413T0100Z/

BULLETIN - EAS ACTIVATION REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
700 PM CDT Mon Apr 12 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Central Llano County in south central Texas...

* Until 800 PM CDT.

* At 659 PM CDT, a severe thunderstorm was located near Field Creek,
  or 16 miles east of Mason, moving east at 20 mph.

  This is a very dangerous storm.

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

  SOURCE...Radar indicated.

  IMPACT...People and animals outdoors will be severely injured. 
           Expect shattered windows, extensive damage to roofs, 
           siding, and vehicles.

* Locations impacted include...
  Llano, Gainesville, Castell, Field Creek, Lone Grove, Stolz, Valley
  Spring and Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3080 9846 3054 9857 3071 9897 3092 9896
TIME...MOT...LOC 2359Z 290DEG 19KT 3082 9897 

HAIL...2.75IN
WIND...60MPH
 
$$

YB
2 follow-up statements
205 
WWUS54 KEWX 130029
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
729 PM CDT Mon Apr 12 2021

TXC299-130100-
/O.CON.KEWX.SV.W.0032.000000T0000Z-210413T0100Z/
Llano TX-
729 PM CDT Mon Apr 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM CDT
FOR CENTRAL LLANO COUNTY...

At 728 PM CDT, a severe thunderstorm was located near Valley Spring,
or 7 miles west of Llano, moving east at 20 mph.

This is a very dangerous storm.

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

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Llano, Gainesville, Castell, Lone Grove, Stolz, Valley Spring and
Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

&&

LAT...LON 3080 9846 3054 9857 3070 9896 3090 9889
TIME...MOT...LOC 0028Z 290DEG 19KT 3077 9880 

HAIL...2.75IN
WIND...60MPH
 
$$

YB
606 
WWUS54 KEWX 130039
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
739 PM CDT Mon Apr 12 2021

TXC299-130100-
/O.CON.KEWX.SV.W.0032.000000T0000Z-210413T0100Z/
Llano TX-
739 PM CDT Mon Apr 12 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 PM CDT
FOR CENTRAL LLANO COUNTY...

At 738 PM CDT, a severe thunderstorm was located near Llano, and is
nearly stationary.

This is a very dangerous storm.

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

SOURCE...Trained weather spotters observed baseball size hail 
         occurring.

IMPACT...People and animals outdoors will be severely injured. 
         Expect shattered windows, extensive damage to roofs, 
         siding, and vehicles.

Locations impacted include...
Llano, Gainesville, Castell, Lone Grove, Stolz, Valley Spring and
Oxford.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This is a dangerous storm. Prepare immediately for large destructive
hail capable of producing significant damage. People outside should
move to a shelter, inside a strong building and away from windows.

&&

LAT...LON 3080 9846 3054 9857 3070 9896 3090 9889
TIME...MOT...LOC 0038Z 290DEG 19KT 3076 9876 

HAIL...2.75IN
WIND...60MPH
 
$$

YB

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 12, 7:53 PM CDTSevere Thunderstorm WarningEWXBurnet, Llano33 min
Apr 12, 9:58 PM CDTSpecial Weather StatementEWXEdwards47 min
Apr 12, 10:42 PM CDTSevere Thunderstorm WarningEWXEdwards, Kerr63 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.