Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 142, NWS Austin/San Antonio, TX

May 28, 2021Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at May 28, 2021, 5:50 PM CDT for Llano County, Texas. It was in force for 40 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 28, 2021, 5:50 PM CDT (22:50 UTC)
Expired: May 28, 2021, 6:30 PM CDT
In force: 40 min
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

County Llano County, TX

The radar

The Ft Hood radar (KGRK), 125 km from the middle of the area, began a volume at 22:50 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.

Issued	Product	Office	Lasted
May 28, 12:14 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 10.8 hours before the alert went out and 254 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3148 J/kg
Mixed-layer CIN: -194 J/kg
Mixed-layer LCL: 844 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 224 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.1

Open this sounding in Storm Lab

The text

As transmitted.

961 
WUUS54 KEWX 282250
SVREWX
TXC299-282330-
/O.NEW.KEWX.SV.W.0142.210528T2250Z-210528T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
550 PM CDT Fri May 28 2021

The National Weather Service in Austin San Antonio has issued a

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

* Until 630 PM CDT.

* At 550 PM CDT, a severe thunderstorm was located near Llano, moving
  east at 15 mph.

  HAZARD...Quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to vehicles is expected.

* Locations impacted include...
  Llano, Gainesville, Stolz, Lone Grove and Oxford. 

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 3063 9883 3079 9875 3083 9850 3053 9852
TIME...MOT...LOC 2250Z 268DEG 14KT 3070 9871 

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

CP

1 follow-up statement

336 
WWUS54 KEWX 282259
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
559 PM CDT Fri May 28 2021

TXC299-282330-
/O.CON.KEWX.SV.W.0142.000000T0000Z-210528T2330Z/
Llano TX-
559 PM CDT Fri May 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM CDT
FOR CENTRAL LLANO COUNTY...

At 559 PM CDT, a severe thunderstorm was located near Llano, moving
east at 15 mph.

HAZARD...Ping pong ball size hail.

SOURCE...Radar indicated.

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

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

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 3063 9883 3079 9875 3083 9850 3053 9852
TIME...MOT...LOC 2259Z 268DEG 14KT 3070 9867 

HAIL...1.50IN
WIND...<50MPH
 
$$

CP

The office that day

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

Issued	Product	Office	Counties	Lasted
May 27, 7:15 PM CDT	Special Weather Statement	EWX	Val Verde	45 min
May 27, 8:15 PM CDT	Special Weather Statement	EWX	Val Verde	45 min
May 27, 8:48 PM CDT	Special Weather Statement	EWX	Val Verde	42 min
May 28, 4:38 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	52 min
May 28, 5:07 PM CDT	Special Weather Statement	EWX	Llano	38 min
May 28, 5:15 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	60 min
May 28, 5:28 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	62 min
May 28, 5:33 PM CDT	Special Weather Statement	EWX	Llano	42 min
May 28, 6:06 PM CDT	Areal Flood Advisory	EWX	Burnet, Llano	3 hr
May 28, 6:12 PM CDT	Severe Thunderstorm Warning	EWX	Blanco, Burnet, Travis, Williamson	63 min
May 28, 6:26 PM CDT	Special Weather Statement	EWX	Burnet	34 min
May 28, 6:39 PM CDT	Severe Thunderstorm Warning	EWX	Blanco, Gillespie	66 min
May 28, 6:46 PM CDT	Areal Flood Advisory	EWX	Travis, Williamson	3 hr

Nearby

Severe Thunderstorm Warnings in Texas, 2021 Every 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.