Alert archive / Texas / Areal Flood Advisories in 2021

Areal Flood Advisory 3, NWS Austin/San Antonio, TX

April 23, 2021Bastrop County, Lee County, Texas

NWS Austin/San Antonio, TX issued this areal flood advisory at Apr 23, 2021, 3:29 PM CDT for Bastrop County, Lee County, Texas. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: Apr 23, 2021, 3:29 PM CDT (20:29 UTC)
Expired: Apr 23, 2021, 6:30 PM CDT
In force: 3 hr
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon

Counties Bastrop County, TX, Lee County, TX

The radar

The Ft Hood radar (KGRK), 62 km from the middle of the area, began a volume at 20:32 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

Corpus Christi, TX (KCRP), launched 12:00Z, 8.5 hours before the alert went out and 276 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: 1041 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 520 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 149 m²/s²
0-3 km storm-relative helicity: 150 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 4.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Austin/San Antonio, TX wrote its last area forecast discussion before this areal flood advisory went out at Apr 23, 2:52 PM CDT, 37 minutes earlier.

Area forecast discussion, Apr 23, 2:52 PM CDT, 37 minutes before

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Hazardous weather outlook, Apr 23, 3:07 PM CDT, 22 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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In the hours before

Special weather statement, Apr 23, 12:19 PM CDT, 3 hours 10 minutes before

Special Weather Statement
National Weather Service Austin/San Antonio TX
1219 PM CDT Fri Apr 23 2021

TXZ205>207-231800-
Guadalupe TX-Comal TX-Bexar TX-
1219 PM CDT Fri Apr 23 2021

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN GUADALUPE...EAST
CENTRAL BEXAR AND EASTERN COMAL COUNTIES UNTIL 100 PM CDT...

At 1219 PM CDT, Doppler radar was tracking a strong thunderstorm over
Cibolo, moving north at 35 mph.

Penny size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
New Braunfels, Schertz, Seguin, Cibolo, Universal City, Selma,
Randolph AFB, Canyon Lake Dam, Canyon Lake, Garden Ridge, McQueeney,
Marion, Santa Clara, New Berlin, Zuehl, Fischer, Converse,
Startzville, Freiheit and Solms.

LAT...LON 2985 9804 2983 9802 2948 9801 2948 9830
      3003 9830 3003 9828
TIME...MOT...LOC 1719Z 184DEG 30KT 2955 9819

HAMPSHIRE

Local storm report, Apr 23, 12:59 PM CDT, 2 hours 30 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1259 PM CDT FRI APR 23 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1241 PM     HAIL             3 SE NEW BRAUNFELS      29.68N 98.10W
04/23/2021  E0.70 INCH       GUADALUPE          TX   PUBLIC

            MPING REPORT OF DIME SIZE HAIL.

&&

EMP

Special weather statement, Apr 23, 12:59 PM CDT, 2 hours 30 minutes before

Special Weather Statement
National Weather Service Austin/San Antonio TX
1259 PM CDT Fri Apr 23 2021

TXZ191-231830-
Hays TX-
1259 PM CDT Fri Apr 23 2021

...SIGNIFICANT WEATHER ADVISORY FOR HAYS COUNTY UNTIL 130 PM CDT...

At 1259 PM CDT, Doppler radar was tracking a strong thunderstorm near
San Marcos, moving north at 40 mph.

Half inch hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
San Marcos, Kyle, Buda, Dripping Springs, Wimberley, Woodcreek,
Uhland, Niederwald, Bear Creek, Driftwood, Mountain City, Hays, Hays
City, San Marcos Regional Airport and Redwood.

A Severe Thunderstorm Watch remains in effect until 800 PM CDT for
south central Texas.

LAT...LON 3026 9804 3005 9774 3004 9773 2992 9784
      2988 9789 2986 9790 2986 9787 2977 9798
      2982 9802 2985 9803 2992 9813
TIME...MOT...LOC 1759Z 197DEG 35KT 2991 9803

HAMPSHIRE

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 23, 12:19 PM CDT	Special Weather Statement	EWX	Comal	41 min
Apr 23, 12:59 PM CDT	Special Weather Statement	EWX	Hays	31 min
Apr 23, 1:17 PM CDT	Severe Thunderstorm Warning	EWX	Caldwell, Guadalupe	23 min
Apr 23, 1:31 PM CDT	Areal Flood Advisory	EWX	Caldwell, Guadalupe	3 hr
Apr 23, 1:43 PM CDT	Severe Thunderstorm Warning	EWX	Bastrop, Travis	25 min
Apr 23, 2:03 PM CDT	Areal Flood Advisory	EWX	Bastrop, Travis	3 hr
Apr 23, 4:15 PM CDT	Special Weather Statement	EWX	Maverick	30 min
Apr 23, 4:39 PM CDT	Severe Thunderstorm Warning	EWX	Maverick, Zavala	51 min
Apr 23, 5:25 PM CDT	Special Weather Statement	EWX	Zavala	50 min
Apr 23, 6:05 PM CDT	Special Weather Statement	EWX	Frio	55 min
Apr 23, 6:29 PM CDT	Special Weather Statement	EWX	Bexar	61 min
Apr 23, 6:45 PM CDT	Severe Thunderstorm Warning	EWX	Bexar, Comal, Guadalupe	45 min
Apr 23, 6:52 PM CDT	Severe Thunderstorm Warning	EWX	Atascosa, Frio	53 min
Apr 23, 6:59 PM CDT	Special Weather Statement	EWX	Atascosa	61 min

Nearby

Areal Flood Advisories in Texas, 2021 Every areal flood advisory 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.