Alert archive / Texas / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 41, NWS Austin/San Antonio, TX

April 15, 2021Gillespie County, Llano County, Texas

NWS Austin/San Antonio, TX issued this severe thunderstorm warning at Apr 15, 2021, 12:15 PM CDT for Gillespie County, Llano County, Texas. It was in force for 60 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: Apr 15, 2021, 12:15 PM CDT (17:15 UTC)
Expired: Apr 15, 2021, 1:15 PM CDT
In force: 60 min
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Hail: 1.75 in
Wind: 60.0 mph

Counties Gillespie County, TX, Llano County, TX

The radar

The Austin/San Antonio radar (KEWX), 116 km from the middle of the area, began a volume at 17:17 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

Time	Report	Where	Remark
Apr 15, 1:10 PM CDT	HAIL 0.7	9 Sse Llano, TX	HAIL UP TO DIME SIZE 9 SSE LLANO ALONG CR 312.
Apr 15, 1:15 PM CDT	HAIL 0.5	9 Ne Enchanted Rock Sta, TX	HALF INCH HAIL REPORTED 13 S LLANO 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.

Issued	Product	Office	Lasted
Apr 15, 8:36 AM CDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 5.3 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-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: 2593 J/kg
Mixed-layer CIN: -44 J/kg
Mixed-layer LCL: 634 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 169 m²/s²
0-3 km storm-relative helicity: 338 m²/s²
Significant tornado parameter: 4.6
Supercell composite: 21.4

Open this sounding in Storm Lab

The text

As transmitted.

339 
WUUS54 KEWX 151715
SVREWX
TXC171-299-151815-
/O.NEW.KEWX.SV.W.0041.210415T1715Z-210415T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Austin/San Antonio TX
1215 PM CDT Thu Apr 15 2021

The National Weather Service in Austin San Antonio has issued a

* Severe Thunderstorm Warning for...
  Northeastern Gillespie County in south central Texas...
  Southwestern Llano County in south central Texas...

* Until 115 PM CDT.

* At 1214 PM CDT, a severe thunderstorm was located over Hilda, or 13
  miles southeast of Mason, moving east at 30 mph.

  HAZARD...Golf ball size hail and 60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Cherry Spring, Prairie Mountain, Crabapple, Oxford, and Enchanted 
  Rock State Natural Area.

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.

&&

LAT...LON 3050 9856 3050 9859 3040 9859 3045 9900
      3050 9920 3050 9897 3068 9896 3070 9857
TIME...MOT...LOC 1714Z 270DEG 27KT 3058 9912 

HAIL...1.75IN
WIND...60MPH
 
$$

BF

2 follow-up statements

583 
WWUS54 KEWX 151740
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
1240 PM CDT Thu Apr 15 2021

TXC171-299-151815-
/O.CON.KEWX.SV.W.0041.000000T0000Z-210415T1815Z/
Gillespie TX-Llano TX-
1240 PM CDT Thu Apr 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM CDT
FOR NORTHEASTERN GILLESPIE AND SOUTHWESTERN LLANO COUNTIES...

At 1239 PM CDT, a severe thunderstorm was located over Prairie
Mountain, or 17 miles southwest of Llano, moving east at 30 mph.

HAZARD...Golf ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Prairie Mountain, Crabapple, Oxford, and Enchanted Rock State 
Natural Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is 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.

&&

LAT...LON 3050 9856 3050 9859 3040 9859 3045 9900
      3050 9897 3068 9896 3070 9857
TIME...MOT...LOC 1739Z 270DEG 27KT 3058 9890 

HAIL...1.75IN
WIND...60MPH
 
$$

BF

527 
WWUS54 KEWX 151748
SVSEWX

Severe Weather Statement
National Weather Service Austin/San Antonio TX
1248 PM CDT Thu Apr 15 2021

TXC171-299-151815-
/O.CON.KEWX.SV.W.0041.000000T0000Z-210415T1815Z/
Gillespie TX-Llano TX-
1248 PM CDT Thu Apr 15 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 115 PM CDT
FOR NORTHEASTERN GILLESPIE AND SOUTHWESTERN LLANO COUNTIES...

At 1248 PM CDT, a severe thunderstorm was located over Enchanted Rock
State Natural Area, or 17 miles north of Fredericksburg, moving east
at 30 mph.

HAZARD...Tennis ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Prairie Mountain, Crabapple, Oxford, and Enchanted Rock State 
Natural Area.

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.

Continuous cloud to ground lightning is 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.

&&

LAT...LON 3050 9856 3050 9859 3040 9859 3045 9900
      3050 9897 3068 9896 3070 9857
TIME...MOT...LOC 1748Z 280DEG 28KT 3052 9882 

HAIL...2.50IN
WIND...60MPH
 
$$

BF

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 15, 7:34 AM CDT	Special Weather Statement	EWX	Kinney	41 min
Apr 15, 8:12 AM CDT	Special Weather Statement	EWX	Edwards	48 min
Apr 15, 8:14 AM CDT	Special Weather Statement	EWX	Kinney	46 min
Apr 15, 8:31 AM CDT	Severe Thunderstorm Warning	EWX	Edwards, Val Verde	59 min
Apr 15, 8:40 AM CDT	Severe Thunderstorm Warning	EWX	Kinney	65 min
Apr 15, 8:55 AM CDT	Special Weather Statement	EWX	Edwards	50 min
Apr 15, 9:04 AM CDT	Severe Thunderstorm Warning	EWX	Edwards	24 min
Apr 15, 9:32 AM CDT	Severe Thunderstorm Warning	EWX	Edwards	17 min
Apr 15, 9:42 AM CDT	Severe Thunderstorm Warning	EWX	Kinney, Uvalde	63 min
Apr 15, 10:42 AM CDT	Severe Thunderstorm Warning	EWX	Uvalde	45 min
Apr 15, 1:07 PM CDT	Severe Thunderstorm Warning	EWX	Blanco, Burnet, Llano, Travis	53 min
Apr 15, 1:52 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Williamson	36 min
Apr 15, 2:07 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Williamson	40 min
Apr 15, 2:57 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Llano	63 min
Apr 15, 3:21 PM CDT	Severe Thunderstorm Warning	EWX	Burnet, Williamson	54 min
Apr 15, 3:56 PM CDT	Severe Thunderstorm Warning	EWX	Travis, Williamson	49 min
Apr 15, 4:11 PM CDT	Special Weather Statement	EWX	Williamson	49 min
Apr 15, 4:36 PM CDT	Severe Thunderstorm Warning	EWX	Bastrop, Lee, Travis, Williamson	54 min
Apr 15, 5:22 PM CDT	Severe Thunderstorm Warning	EWX	Bastrop, Fayette, Lee	29 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.