Alert archive / Texas / Areal Flood Advisories in 2021

Areal Flood Advisory 12, NWS Austin/San Antonio, TX

May 1, 2021Lavaca County, Texas

NWS Austin/San Antonio, TX issued this areal flood advisory at May 1, 2021, 3:09 AM CDT for Lavaca County, Texas. It was in force for 51 min.

The area

The counties it named.

The facts

Issued: May 1, 2021, 3:09 AM CDT (08:09 UTC)
Expired: May 1, 2021, 4:00 AM CDT
In force: 51 min
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon

County Lavaca County, TX

The radar

The Austin/San Antonio radar (KEWX), 112 km from the middle of the area, began a volume at 08:10 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 00:00Z, 8.2 hours before the alert went out and 188 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: 42 J/kg
Mixed-layer CIN: -278 J/kg
Mixed-layer LCL: 901 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 69 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

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 May 1, 1:45 AM CDT, 1 hour 24 minutes earlier.

Area forecast discussion, May 1, 1:45 AM CDT, 1 hour 24 minutes before

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Hazardous weather outlook, Apr 30, 3:36 AM CDT, 23 hours 33 minutes before

Hazardous Weather Outlook
National Weather Service Austin/San Antonio TX
336 AM CDT Fri Apr 30 2021

TXZ171>173-183>194-202>209-217>225-228-011200-
Llano-Burnet-Williamson-Val Verde-Edwards-Real-Kerr-Bandera-
Gillespie-Kendall-Blanco-Hays-Travis-Bastrop-Lee-Kinney-Uvalde-
Medina-Bexar-Comal-Guadalupe-Caldwell-Fayette-Maverick-Zavala-
Frio-Atascosa-Wilson-Karnes-Gonzales-De Witt-Lavaca-Dimmit-
336 AM CDT Fri Apr 30 2021

This Hazardous Weather Outlook is for South-Central Texas..

.DAY ONE...Today And Tonight.

Numerous showers and scattered thunderstorms are forecast to
continue today and tonight. The heaviest rainfall is expected
across the Coastal Plains where accumulations could reach 2-4
inches with isolated totals in excess of 6 inches. A Flash Flood
Watch is in effect for locations south and east of a Pleasanton
to New Braunfels to Fayetteville line.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Numerous showers and scattered thunderstorms are forecast to
continue into Saturday night. The Flash Flood Watch will remain
in effect for locations south and east of a Pleasanton to New
Braunfels to Fayetteville line through Saturday evening. A strong
to marginally severe storm is also possible Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to submit storm or flooding reports to
the National Weather Service.

In the hours before

Local storm report, Apr 30, 9:21 PM CDT, 5 hours 48 minutes before

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Local storm report, Apr 30, 9:35 PM CDT, 5 hours 34 minutes before

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Local storm report, Apr 30, 9:36 PM CDT, 5 hours 33 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 30, 8:01 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Comal	2 hr
Apr 30, 8:17 PM CDT	Special Weather Statement	EWX	Terrell	28 min
Apr 30, 8:22 PM CDT	Areal Flood Advisory	EWX	Bexar, Guadalupe, Wilson	50 min
Apr 30, 9:12 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Bexar, Guadalupe, Wilson	3 hr
Apr 30, 11:59 PM CDT	Areal Flood Advisory	EWX	Lavaca	3 hr
May 1, 3:57 AM CDT	Flash Flood Warning Considerable damage threat	EWX	Lavaca	3 hr
May 1, 8:10 AM CDT	Special Weather Statement	EWX	Maverick	35 min
May 1, 8:23 AM CDT	Special Weather Statement	EWX	Dimmit	52 min
May 1, 9:10 AM CDT	Special Weather Statement	EWX	Dimmit	35 min
May 1, 9:24 AM CDT	Special Weather Statement	EWX	Zavala	36 min
May 1, 9:55 AM CDT	Areal Flood Advisory	EWX	Kinney, Maverick, Uvalde, Val Verde, Zavala	3 hr
May 1, 10:02 AM CDT	Special Weather Statement	EWX	Uvalde, Zavala	43 min
May 1, 10:36 AM CDT	Special Weather Statement	EWX	Frio, Medina, Uvalde	54 min
May 1, 10:49 AM CDT	Areal Flood Advisory	EWX	Bandera, Frio, Medina	3 hr
May 1, 11:15 AM CDT	Flash Flood Warning Considerable damage threat	EWX	Medina, Uvalde	4 hr
May 1, 11:18 AM CDT	Areal Flood Advisory	EWX	Uvalde	3 hr
May 1, 11:31 AM CDT	Special Weather Statement	EWX	Atascosa, Bexar, Medina	59 min
May 1, 11:44 AM CDT	Areal Flood Advisory	EWX	Bandera, Gillespie, Kerr, Medina	4 hr
May 1, 12:01 PM CDT	Areal Flood Advisory	EWX	Atascosa	3 hr
May 1, 12:09 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Bexar	4 hr
May 1, 12:30 PM CDT	Special Weather Statement	EWX	Atascosa, Bexar, Wilson	45 min
May 1, 12:40 PM CDT	River Flood Warning	EWX	Bexar	32 hr
May 1, 1:03 PM CDT	Areal Flood Advisory	EWX	Comal	3 hr
May 1, 1:14 PM CDT	Special Weather Statement	EWX	Comal, Guadalupe, Karnes, Wilson	61 min
May 1, 1:22 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Comal, Guadalupe, Wilson	3 hr
May 1, 1:52 PM CDT	Areal Flood Advisory	EWX	Gillespie, Kendall	3 hr
May 1, 2:07 PM CDT	River Flood Warning	EWX	Bexar, Wilson	41 hr
May 1, 2:07 PM CDT	Special Weather Statement	EWX	Caldwell, Gonzales, Guadalupe	38 min
May 1, 2:27 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Caldwell, Hays	3 hr
May 1, 2:44 PM CDT	Areal Flood Advisory	EWX	Gonzales	3 hr
May 1, 2:58 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Bastrop, Travis	3 hr
May 1, 3:11 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Gonzales	3 hr
May 1, 3:39 PM CDT	Areal Flood Advisory	EWX	Lee, Williamson	3 hr
May 1, 4:11 PM CDT	Flash Flood Warning Considerable damage threat	EWX	Williamson	3 hr
May 1, 4:14 PM CDT	Areal Flood Advisory	EWX	Bexar	2 hr
May 1, 4:25 PM CDT	Areal Flood Advisory	EWX	Lavaca	3 hr
May 1, 4:31 PM CDT	Special Weather Statement	EWX	Bandera, Kerr	44 min
May 1, 6:13 PM CDT	Areal Flood Advisory	EWX	Bandera, Gillespie, Kendall, Kerr	3 hr
May 1, 6:53 PM CDT	Areal Flood Advisory	EWX	Gillespie, Kendall	3 hr

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.