Flash Flood Warning 22, NWS Austin/San Antonio, TX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
645 AM CDT Tue Aug 30 2022

...New AVIATION...

.SHORT TERM...
(Today through Wednesday)
Issued at 156 AM CDT Tue Aug 30 2022

The highlight of the short term period will be the potential for
locally heavy rainfall as scattered to numerous showers and
thunderstorms develop across the region.

Current WV and upper level analysis depicts an area of low pressure
associated with the ongoing showers and storms across a good portion
of central into west TX. This system will continue to move southeast
through this morning and will be one source for precipitation
throughout the day. The other source, in combination with PWATs from
1.8 to 2.2 inches already in place across the region, will be an
upper level inverted trough currently situated over Louisiana and
the Upper Texas Coast. The forcing from these two upper level
features in addition to diurnal heating should result in the
development of scattered to numerous thunderstorms throughout the
day. WPC has upgraded to a slight risk for excessive rainfall in
their Day 1 outlook across the western portion of the CWA due to the
potential for multiple rounds of heavy rainfall today in combination
with recent rainfall from the past couple of weeks. The remainder of
the CWA is under a marginal risk due to the potential for minor
flooding with slow moving and/or training storms.

Shower and thunderstorm coverage is expected to diminish significantly
around 00Z this evening, though activity may continue into Wednesday
across the Rio Grande Plains as the upper level low lingers across
northern Mexico. Additional development is expected to blossom
through the day Wednesday across the CWA, though slightly greater
coverage of showers and storms is expected across central and western
portions of the CWA as the upper level slow begins to slowly pull
west. This is reflected in the Day 2 ERO as much of the CWA with the
exception of the Coastal Plains is under a marginal risk for
excessive rainfall.

As far as QPF goes, the HREF 48-hour probability-matched mean ending
00Z Wednesday evening depicts the potential for widespread totals in
the 1-2 inch range with higher totals in the 3-5 inch range possible
across the Rio Grande Plains. Expect high temperatures on average to
be a few degrees below normal due to the increased moisture and
cloud cover.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 156 AM CDT Tue Aug 30 2022

The upper level low over West Texas today retrogrades west into
northwest Mexico Wednesday with ridging expanding east through the
Texas Panhandle and Oklahoma. This is temporary, as models are in
good agreement with left over vorticity across West Central Texas
combining into a short-wave trough eroding the ridge across North
Texas and Oklahoma on Thursday, then expanding the new trough axis
southwest into South Central Texas Friday.

Elevated moisture content will remain pooled over much of the region
through much of the extended forecast, with precipitable water
values forecast to be in the 1.8-2.3 range, above the CFSR 90th
percentile. Earlier runs of the ECMWF and Canadian had indicated the
possibility of much lower moisture water content moving into the
region Friday and Saturday, but recent runs have backed off this. It
appears chances will remain good for daily scattered showers and
thunderstorms Thursday through Saturday given the elevated moisture
pool and weakness aloft. Mesoscale influences, and a diffuse cold
front Friday, could come into play as well. There is the potential
for some pockets of locally heavy rainfall, with models keying on
Friday.

Better confidence exists this morning with respect to the tropical
wave in the western Caribbean Sea. As thought yesterday, the GFS was
too aggressive with a vorticity maximum spinning off the Central
American Gyre and development of a tropical cyclone. Recent runs of
the GFS and it's ensemble members have backed way off this and are
now in agreement with the ECMWF and Canadian ensembles that the
tropical wave combines with a broad trough over the northeast Gulf
and advances west as a weak inverted trough into the Mexico and
Texas coasts over the weekend. This, in combination with the mid and
upper level weakness, should continue rain chances Sunday and Monday
across South Central Texas. The National Hurricane Center has ended
the outlooked area in the northwest Caribbean Sea.

&&

.AVIATION...
(12Z TAFS)
Issued at 645 AM CDT Tue Aug 30 2022

MVFR cigs will prevail at the I-35 terminals through this morning
and return early Wednesday morning. MVFR to IFR conditions will be
possible this morning at KDRT as a line of thunderstorms slowly moves
from west to east. Otherwise, shower and eventually thunderstorm
coverage should begin to increase into the afternoon hours across the
remainder of south-central Texas. Exact timing of showers and storms
at terminals is difficult to pin down due to their forecasted
scattered nature, so for now we will continue with VCSH/VCTS mention
in the TAFs and add TEMPOs as needed once we see some development in
real time. Shower and thunderstorm coverage should diminish around
00Z this evening for most locations, but coverage could linger near
KDRT through the period. Winds will mostly be light with the possible
exception of gusty and erratic winds in and around storms.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              90  74  93  75 /  70  40  60  40
Austin Bergstrom Intl Airport  89  74  92  75 /  70  30  60  40
New Braunfels Muni Airport     90  74  93  74 /  70  40  60  30
Burnet Muni Airport            88  72  90  73 /  70  40  70  40
Del Rio Intl Airport           90  74  87  75 /  70  60  70  50
Georgetown Muni Airport        88  74  91  74 /  70  40  60  40
Hondo Muni Airport             92  74  90  74 /  70  50  60  30
San Marcos Muni Airport        90  74  93  74 /  70  40  60  30
La Grange - Fayette Regional   89  74  90  74 /  70  30  50  30
San Antonio Intl Airport       90  75  90  76 /  70  40  60  30
Stinson Muni Airport           91  76  92  76 /  70  40  60  30

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

Short-Term...Gale
Long-Term...76
Aviation...Gale

Hazardous Weather Outlook
National Weather Service Austin/San Antonio TX
310 AM CDT Tue Aug 30 2022

TXZ171>173-183>194-202>209-217>225-228-310815-
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-
310 AM CDT Tue Aug 30 2022

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

.DAY ONE...Today And Tonight.

Scattered to numerous showers and thunderstorms are expected
across all of south central Texas today, and across the Rio Grande
Plains through tonight. Quick, heavy rainfall with isolated
totals over two inches could lead to minor flooding, especially
across the Rio Grande Plains.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Scattered to numerous showers and thunderstorms will be possible
Wednesday through Friday. A few spots could see heavy rain totals
over two inches, leading to isolated flooding potential.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
712 AM CDT TUE AUG 30 2022

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

0712 AM     FLASH FLOOD      7 ENE UTOPIA            29.67N 99.42W
08/30/2022                   BANDERA            TX   LAW ENFORCEMENT

            WATER REPORTED OVER THE ROAD AT F.M. 470 AND
            SECO CREEK.

&&

JR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
843 AM CDT TUE AUG 30 2022

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

0626 AM     FLASH FLOOD      1 NNW DEL RIO           29.38N 100.90W
08/30/2022                   VAL VERDE          TX   PUBLIC

            SOCIAL MEDIA POST SHOWING FLOODED ROADWAY AT
            THE INTERSECTION OF VETERANS BOULEVARD AND
            10TH STREET IN DEL RIO.

&&

EMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
851 AM CDT TUE AUG 30 2022

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

0844 AM     FLASH FLOOD      2 NW DEL RIO            29.39N 100.92W
08/30/2022                   VAL VERDE          TX   LAW ENFORCEMENT

            THE DEL RIO POLICE REPORTS SEVERAL FLOODED
            ROADWAYS IN THE CITY OF DEL RIO.

&&

EMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
909 AM CDT TUE AUG 30 2022

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

0856 AM     FLASH FLOOD      1 S CAMP WOOD           29.65N 100.01W
08/30/2022                   REAL               TX   LAW ENFORCEMENT

            THE TEXAS DEPARTMENT OF TRANSPORTATION HAS
            CLOSED STATE HIGHWAY 55 SOUTH OF CAMP WOOD
            DUE TO FLOODING.

&&

EMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
917 AM CDT TUE AUG 30 2022

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

0857 AM     FLASH FLOOD      4 NW BARKSDALE          29.77N 100.08W
08/30/2022                   EDWARDS            TX   LAW ENFORCEMENT

            THE EDWARDS COUNTY SHERIFFS OFFICE REPORTS
            SEVERAL LOW WATER CROSSINGS ARE FLOODED AND
            IMPASSABLE NEAR BARKSDALE ALONG STATE
            HIGHWAY 55.

&&

EMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
1023 AM CDT TUE AUG 30 2022

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

1015 AM     FLASH FLOOD      1 NE BARKSDALE          29.73N 100.03W
08/30/2022                   EDWARDS            TX   PUBLIC

            FLOODED LOW WATER CROSSING WITH SWIFT WATER
            VIA VIDEO POSTED ON SOCIAL MEDIA ON DRY
            CREEK RD (CR 381).

&&

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