Alert archive / Texas / Special Weather Statements in 2021

Special Weather Statement, NWS Austin/San Antonio, TX

September 6, 2021Bexar County, Texas

NWS Austin/San Antonio, TX issued this special weather statement at Sep 6, 2021, 4:39 PM CDT for Bexar County, Texas. It was in force for 66 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
Sep 6, 2021, 4:39 PM CDT (21:39 UTC)
Expired
Sep 6, 2021, 5:45 PM CDT
In force
66 min
Issued by
NWS Austin/San Antonio, TX
Hail
0.50 in
Wind
55

County Bexar County, TX

The radar

The Austin/San Antonio radar (KEWX), 78 km from the middle of the area, began a volume at 21:41 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 nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 9.7 hours before the alert went out and 204 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 12:00Z on 2021-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 103 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 12:00Z on 2021-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -47 square meters per square second.1939Sfc1 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
103 J/kg
Mixed-layer CIN
-269 J/kg
Mixed-layer LCL
1941 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
-47 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

Open this sounding in Storm Lab

The text

As transmitted.

818 
WWUS84 KEWX 062139
SPSEWX

Special Weather Statement
National Weather Service Austin/San Antonio TX
439 PM CDT Mon Sep 6 2021
 
TXZ204-205-220-062245-
Atascosa TX-Bexar TX-Medina TX-
439 PM CDT Mon Sep 6 2021

...Strong thunderstorms will impact portions of east central Medina,
northwestern Atascosa and western Bexar Counties through 545 PM
CDT...

At 439 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Helotes to near Stinson Municipal Airport.
Movement was south at 20 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
San Antonio, Castroville, San Antonio Int Airport, Stinson Municipal
Airport, Leon Valley, Helotes, Kirby, Alamo Heights, Terrell Hills,
Shavano Park, Hollywood Park, Cross Mountain, Lytle, Olmos Park,
Somerset, Natalia, China Grove, Lacoste, Noonan and The Dominion.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 2925 9900 2906 9853 2942 9834 2973 9859
      2947 9896
TIME...MOT...LOC 2139Z 021DEG 16KT 2961 9870 2940 9844 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...55 MPH

$$

MO

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 5, 8:21 PM CDTAreal Flood AdvisoryEWXWilliamson2 hr
Sep 6, 2:32 PM CDTSpecial Weather StatementEWXGuadalupe28 min
Sep 6, 3:01 PM CDTSpecial Weather StatementEWXGuadalupe44 min
Sep 6, 3:03 PM CDTSpecial Weather StatementEWXBastrop42 min
Sep 6, 3:45 PM CDTSpecial Weather StatementEWXCaldwell, Fayette, Hays, Travis45 min
Sep 6, 3:47 PM CDTSpecial Weather StatementEWXBexar, Guadalupe43 min
Sep 6, 3:50 PM CDTSpecial Weather StatementEWXKendall55 min
Sep 6, 4:17 PM CDTSevere Thunderstorm WarningEWXCaldwell, Comal, Guadalupe, Hays58 min
Sep 6, 4:24 PM CDTSpecial Weather StatementEWXKendall51 min
Sep 6, 4:35 PM CDTSpecial Weather StatementEWXBandera, Edwards, Kinney, Medina, Real, Uvalde55 min
Sep 6, 4:51 PM CDTAreal Flood AdvisoryEWXBandera, Bexar, Comal, Kendall, Kerr, Medina3 hr
Sep 6, 5:02 PM CDTSpecial Weather StatementEWXHays58 min
Sep 6, 5:06 PM CDTSpecial Weather StatementEWXGonzales, Lavaca54 min
Sep 6, 5:19 PM CDTAreal Flood AdvisoryEWXBlanco, Comal, Hays, Kendall3 hr
Sep 6, 5:35 PM CDTSpecial Weather StatementEWXBlanco40 min
Sep 6, 6:19 PM CDTFlash Flood Warning Considerable damage threatEWXBlanco3 hr

Nearby

Special Weather Statements in Texas, 2021Every special weather statement 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.