651
FXUS64 KEWX 211816
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
116 PM CDT Fri Aug 21 2026

...New SHORT TERM, LONG TERM...

.KEY MESSAGES...
Updated at 108 PM CDT Fri Aug 21 2026

- Heat Advisory in effect form the northern Hill Country, I-35
  Corridor, and Coastal Plains Thursday-Sunday.

- Brief and isolated storms possible over Central TX Saturday.

- August heat wave continues with no significant rain or heat
  relief in sight.

&&

.SHORT TERM...
(Tonight through Saturday night)
Issued at 108 PM CDT Fri Aug 21 2026

An upper level high is centered over the southern Rockies with the
ridge extending over Texas where the flow is weakly anticyclonic.
At the surface, high pressure centered over the Gulf is producing
winds from the south. The airmass over South-Central Texas remains
hot and moist with little change in temperatures or dewpoints over
the last 24 hours. The upper ridge will continue to dominate
through the short term period. We expect very little change to the
weather. Although a front will move into north Texas Saturday with
convection possible into central Texas. We have continued to show
15%-20% POPs over the northeastern counties Saturday afternoon and
early evening. High temperatures might be a degree or two warmer
Saturday and a few spots could reach 105 degrees, but we will
stick with the Heat Advisory with limited coverage for the highest
temperatures.


&&

.LONG TERM...
(Sunday through next Friday)
Issued at 108 PM CDT Fri Aug 21 2026

The upper ridge will remain over Texas through the long term. We
expect only minor changes through the period. Subsidence will
prevent any convection through next week. Temperatures may
fluctuate a few degrees up or down each day, but generally highs
will be around 100 each day for most of the area outside the
highest parts of the Hill Country and southern Edwards Plateau.
Models show some better vertical mixing bringing lower dewpoint
air to the surface and thus lower heat indices. If this pans out
we will not need Heat Advisories.

&&

.AVIATION...
(18Z TAFS)
Issued at 1221 PM CDT Fri Aug 21 2026

Very little if any change from the previous forecast. VFR ceilings
are expected along with winds out of the southeast. Some low
clouds may form at AUS, SAT, and SSF overnight, but MVFR stratus
is not expected at this time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              80 105  80 105 /   0  20  20   0
Austin Bergstrom Intl Airport  79 104  79 104 /   0  20  20   0
New Braunfels Muni Airport     77 104  77 103 /   0  10  10   0
Burnet Muni Airport            76 104  77 102 /   0  20  20   0
Del Rio Intl Airport           78 105  77 103 /   0   0   0   0
Georgetown Muni Airport        79 104  80 104 /   0  20  20   0
Hondo Muni Airport             76 103  75 102 /   0   0   0   0
San Marcos Muni Airport        76 103  77 103 /   0  10  10   0
La Grange - Fayette Regional   78 104  78 104 /   0  20  20   0
San Antonio Intl Airport       78 103  78 103 /   0   0  10   0
Stinson Muni Airport           78 104  77 104 /   0   0   0   0

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT Sunday for TXZ171>173-191>194-
205>209-220>225.

&&

$$

SHORT TERM...05
LONG TERM....05
AVIATION...MMM