Flash Flood Warning 15, NWS Austin/San Antonio, TX

781 
WGUS74 KEWX 200656
FFSEWX

Flash Flood Statement
National Weather Service Austin/San Antonio TX
156 AM CDT Wed May 20 2026

TXC491-200706-
/O.EXP.KEWX.FF.W.0015.000000T0000Z-260520T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Williamson TX-
156 AM CDT Wed May 20 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 2 AM CDT EARLY THIS MORNING 
FOR NORTHWESTERN WILLIAMSON COUNTY...

The heavy rain has ended. Please continue to heed remaining road 
closures.

&&

LAT...LON 3078 9796 3091 9783 3087 9762 3078 9740
      3073 9768

$$

27

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
648 PM CDT Tue May 19 2026

...New UPDATE, AVIATION...

.KEY MESSAGES...

- Line of strong to severe storms with locally heavy rain possible
  this evening into tonight.

- Active weather pattern continues through the upcoming Memorial
  Holiday weekend. Rounds of storms with heavy rain could lead to
  localized flooding.

&&

.UPDATE...
Issued at 632 PM CDT Tue May 19 2026

We'll see another rapidly upscaling storm pattern this evening.
Edwards Plateau and Hill Country counties are under SVR Watch 232
through 4Z and Central TX counties surrounding Austin metro are
under SVR Watch 233 through 06Z. We expect most of the hail and
wind to be on the lower side of severe as the congealing into the
upscaled line will probably replace the discrete cells in the next
hour or two. The areas currently under the congealing cells could
get enough training for some localized flooding in the next hour
or two as well with spotty 3-5 inch amounts possible by midnight.
Late evening motions should pick up some, so the metro cities
might see only a inch or so but could still see some minor
flooding if 2 inch amounts occur.

&&

.SHORT TERM...
(Tonight through Wednesday night)
Issued at 138 PM CDT Tue May 19 2026

At approximately 1 PM noon CDT, satellite and observations indicated
a cold front to our north slowly pushing towards the Edwards
Plateau. Subsidence from an MCS over South Texas last night helped
to produce clearer skies than anticipated over our area this morning
and has also modified the mid-level flow relative to previous model
forecasts, making today's forecast less confident than usual.
Namely, subsidence has allowed an area of drier and warmer near-
surface air to take root around the Hill Country, but as moist Gulf
air returns this afternoon this may restore more conducive
conditions for storm development.

The clearer skies should allow daytime warming to promote large
amounts of conditional instability over South-Central Texas, to the
tune of 3000-4000 J/kg of SBCAPE, and as the front to our north and
a dry line to our west encounters this air with the aid of broad
southwesterly flow aloft, we do expect that the overhead cap sampled
in aircraft observations from near AUS and SAT will eventually be
overcome in part by developing thunderstorms along the
aforementioned features.

The afternoon should remain mostly dry, but storms may begin
developing in earnest around the periphery of South-Central Texas
mainly after 5 PM CDT. The broader environment continues to favor a
line of storms pushing south or southeast across our area, though
given the wrinkles to the mid-troposphere there's some disagreement
over where storms will form first, largely due to uncertainties with
the current bubble of drier air over the Hill Country. The weak
front enabling many of these storms will be sluggish, so whatever
portion gets active first will have the best shot of becoming the
dominant driver of storms this evening/tonight.

There are going to be a few areas to initially monitor for storms as
we head to the late afternoon into the evening: the front to our
north, the dry line near the Rio Grande which extends into the
Edwards Plateau, and a lower potential for some isolated activity
with some moisture convergence ahead of these features on the I-35
corridor. The primary severe potential today arises from the storms
on the front and dry line. The SPC continues to highlight up to a
Level 2 of 5 (Slight) risk for severe weather over most of our area
this evening. Some of the initial development over the Edwards
Plateau could produce isolated large hail, but as storms start to
congeal, the risk should lean more towards a potential damaging wind
threat if bowing segments begin to materialize from the storm
clusters. The heavy rain threat and the potential for isolated flash
flooding will also need to be monitored as any slow-moving storm
ahead of the front/dry line and higher rates within the lines of
storms could drive up rain totals. Areas that catch the main storm
complexes could see totals generally above 1" with isolated pockets
above 3" within the moist environment with PWATs above the 90th
percentile. Uncertainty in the overall timing of this event is
somewhat high, but we expect most activity will tend to be
concentrated in the evening and first half of the night, clearing
out early Wednesday morning.

Slightly cooler conditions should prevail in the wake of these
storms Wednesday morning. A moist airmass should still remain in
place aloft, though the atmosphere will take some time to reload.
Temperatures will be a bit more moderated with forecast highs in the
80s. Most of the Wednesday will thus be on the drier side, but as we
head later in the day sufficient destabilization and an approaching
shortwave trough over West Texas could spark another round of
activity along the Rio Grande late afternoon / evening on Wednesday,
preferentially along the dry line. Instability should be somewhat
lower for these storms compared to today's action, resulting in a
lower severe threat. However, these storms could produce locally
heavy rain if they advance east Wednesday night into areas saturated
by earlier storms. The moist environment could allow these storms to
maintain strength with sufficient energy aloft, leading to good rain
chances extending from the Rio Grande eastward to the Hill Country,
I-35 corridor, and Coastal Plains Wednesday night into Thursday
morning.

&&

.LONG TERM...
(Thursday through next Tuesday)
Issued at 138 PM CDT Tue May 19 2026

The wet pattern that kicks off today should continue through the
week as persistent upper-level southwesterly flow continues to carve
out a favorable pathway for multiple disturbances over our area
overlapping atop moist Gulf air.

Each round of storms will influence the following day's storm
potential, so confidence on precise timing and placement for any
activity is low in the long-term forecast. However, based on the
broader synoptic environment, a shortwave impulse Thursday could
produce another round of activity late Thursday into early Friday. A
more pronounced upper-level disturbance may push into the area over
the weekend, indicating another favorable time window for
potentially widespread rains. The rather stagnant upper-air pattern
keeps moisture in our area through early next week, with a lack of
clear indicators for a definitive ending to this wet pattern into
early next week.

Repeated rounds of rainfall will further moisten soils, increasing
the broader potential for more surface runoff from rain as grounds
saturate. The pattern may lead to widespread beneficial rain for
most areas, but the most impacted portions with higher totals and
rain rates may see an increasing likelihood for flash flooding or
river flooding. Due to the dependence of each round of storms on the
previous salvo of activity, it is impractical at this forecast range
to pinpoint the areas that will be receiving the most rain, and in
general, model precipitation forecasts spread substantial totals
across virtually all of the South-Central Texas. Continue to check
the forecast as the week progresses for those with plans this
weekend for the Memorial Day holiday.

&&

.AVIATION...
(00Z TAFS)
Issued at 632 PM CDT Tue May 19 2026

Will keep to a general HRRR/RRFS trend on a convective complex
moving through the 4 TAF sites from 02Z to 07Z, catching the AUS
area first and SAT/SSF last. Leading edge of activity could
produce some 40 knot gusts, but will only show 30 knots in the
TEMPO groups. Somewhat fast evening arrival has us not expecting
any IFR CIGs for now and there could be some MCS stratiform rain
following the activity to preclude low cloudines after the thunder
stops. Will show some late morning MVFR cigs but keep a stable VFR
picture in the later periods, assuming we'll get over 80 percent
coverage of storms and a worked over air mass by early Wednesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              71  84  71  82 /  80  40  60  90
Austin Bergstrom Intl Airport  72  84  71  82 /  80  40  60  90
New Braunfels Muni Airport     71  84  70  83 /  80  40  60  80
Burnet Muni Airport            68  81  68  79 /  70  40  70  80
Del Rio Intl Airport           70  86  68  86 /  70  40  80  20
Georgetown Muni Airport        70  82  69  80 /  80  40  60  90
Hondo Muni Airport             70  84  69  82 /  80  30  80  70
San Marcos Muni Airport        71  84  71  82 /  80  40  60  90
La Grange - Fayette Regional   72  84  72  82 /  80  50  50  90
San Antonio Intl Airport       72  85  72  83 /  80  30  70  80
Stinson Muni Airport           72  85  72  84 /  80  30  70  80

&&

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

SHORT TERM...Tran
LONG TERM....Tran
AVIATION...18

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
819 PM CDT Tue May 19 2026

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

0811 PM     Flood            9 NNE Burnet            30.88N 98.15W
05/19/2026                   Burnet             TX   Fire Dept/Rescue

            Burnet County EM relayed a volunteer fire
            department report of flooding over County
            Roads 202 and 203.

&&

MO

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
823 PM CDT Tue May 19 2026

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

0819 PM     Hail             Andice                  30.78N 97.85W
05/19/2026  M1.00 Inch       Williamson         TX   Trained Spotter

            Quarter sized hail reported by trained
            spotter at Andice.

&&

MO

Special Weather Statement
National Weather Service Austin/San Antonio TX
823 PM CDT Tue May 19 2026

TXZ185-186-188-189-200215-
Gillespie TX-Kerr TX-Real TX-Kendall TX-
823 PM CDT Tue May 19 2026

...Strong thunderstorms will impact portions of Kerr, Gillespie,
northwestern Kendall and northeastern Real Counties through 915 PM
CDT...

At 823 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from Stonewall to near Tivydale to 12 miles south of
Telegraph. Movement was southeast at 25 mph.

HAZARD...Wind gusts up to 50 mph and penny size 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...
Kerrville, Fredericksburg, Comfort, Ingram, Hunt, Stonewall,
Tivydale, Kerrville-Schreiner Park, Rocky Hill, Kerr Wildlife
Management Area, Waltonia, Blumenthal, Center Point, Crabapple,
Grapetown, Cherry Spring, Luckenbach, Cain City, Old Tunnel State
Park, and Doss.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Severe Thunderstorm Watch remains in effect until 1100 PM CDT for
south central Texas. A Severe Thunderstorm Watch also remains in
effect until 100 AM CDT for south central Texas.

&&

LAT...LON 3050 9888 3011 9856 2992 9904 2991 9968
      3007 9976 3029 9976 3029 9930 3050 9930
TIME...MOT...LOC 0123Z 300DEG 22KT 3027 9866 3019 9915 3014 9993

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

62

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
856 PM CDT Tue May 19 2026

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

0851 PM     Tstm Wnd Dmg     2 NE Georgetown         30.67N 97.67W
05/19/2026                   Williamson         TX   Amateur Radio

            Amateur Radio Network report of a 12 inch
            diameter tree snapped at Stadium Drive and
            North Austin Avenue in Georgetown.

&&

MO

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
901 PM CDT Tue May 19 2026

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

0851 PM     Flash Flood      11 W Briggs             30.91N 98.10W
05/19/2026                   Burnet             TX   Emergency Mngr

            CR 208 reported as impassable by Northeast
            Burnet County Fire and Rescue.

&&

MO

Preliminary Local Storm Report
National Weather Service Austin/San Antonio TX
910 PM CDT Tue May 19 2026

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

0905 PM     Tstm Wnd Gst     4 W Sunset Valley       30.23N 97.87W
05/19/2026  E60 MPH          Travis             TX   Broadcast Media

            Power flashes in Oak Hill area of Austin. 50
            to 60 mph winds estimated by news media.

&&

MO