218
FXUS64 KEWX 192322
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
622 PM CDT Wed Aug 19 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 618 PM CDT Wed Aug 19 2026

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

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

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 123 PM CDT Wed Aug 19 2026

Regional satellite imagery clearly depicts the 500mb ridge centered
over Arizona early this afternoon. The ridge itself is a bit more
elongated from west to east, stretching over Texas. Underneath it, a
weak tropical wave is moving inland over South Texas, but this will
only send some mid to upper level cloud cover our way. Rain chances
remain zero. Today will be yet another scorcher with highs ranging
from 97 to 103, with heat indices higher in the Coastal Plains were
mixing will be a bit lower.

On Thursday, we have opted to go with a Heat Advisory for Llano and
Burnet, in addition to the I-35 Corridor and Coastal Plains. This
advisory will stretch all the way through Sunday, and while
temperatures should cool into the 70s for most at night, it`s the
rapid warm-up and steady rise in ambient air temperatures that makes
things a bit more concerning from a safety aspect. Thursday won`t be
as hot as Friday-Sunday, but temperatures ranging from 100-104 are
likely with heat indices climbing to 108-110 at times, particularly
over the Coastal Plains. Once again, dry weather is expected with no
rain chances in the forecast.

&&

.LONG TERM...
(Friday through next Wednesday)
Issued at 123 PM CDT Wed Aug 19 2026

The 500mb ridge steadily migrates eastward and by Friday/Saturday,
it will be centered over the Texas Panhandle. At the 700mb level,
the thermal ridge will be centered directly over Texas, so strong
subsidence and sunny skies should be the normal through the weekend.
Heat advisories will continue this weekend and actual air
temperatures may approach warning levels (105+) for the Austin metro
this weekend. Trends will be monitored for a possible upgrade to
Extreme Heat Warning, but for now, expect highs in the 99-104 range
for most locations through Sunday. Unfortunately, despite a brief
lull and advisory level temperatures Monday-Tuesday, ridging will be
in even greater control by mid to late next week, and highs in the
100-106 range look like a good bet. At this distance, little relief
is in sight through the end of August, but a pattern change may be
in the works as El Nino continues to strengthen over the Equatorial
Pacific, which may result in increased rain chances in early to mid-
September.

&&

.AVIATION...
(00Z TAFS)
Issued at 618 PM CDT Wed Aug 19 2026

Mostly clear and VFR conditions are expected throughout the region
tonight into Thursday afternoon. Typical increase in southeast
wind is expected at KAUS/KSAT/KSSF generally 02Z-06Z with the
seabreeze before winds lessen. Onshore moisture will be higher and
could produce a brief window of MVFR CIGs east of KAUS/KSAT near
12Z. However, chances are generally below 30 percent.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              78 103  78 104 /   0   0   0   0
Austin Bergstrom Intl Airport  77 103  77 103 /   0   0   0   0
New Braunfels Muni Airport     76 102  76 102 /   0   0   0   0
Burnet Muni Airport            75 101  75 101 /   0   0   0   0
Del Rio Intl Airport           78 102  78 102 /   0   0   0   0
Georgetown Muni Airport        78 102  78 102 /   0   0   0   0
Hondo Muni Airport             73 100  73 102 /   0   0   0   0
San Marcos Muni Airport        76 102  76 102 /   0   0   0   0
La Grange - Fayette Regional   77 103  77 103 /   0   0   0   0
San Antonio Intl Airport       78 102  77 102 /   0   0   0   0
Stinson Muni Airport           77 103  77 103 /   0   0   0   0

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 2 PM Thursday to 7 PM CDT Sunday for
TXZ171>173-191>194-205>209-220>225.

&&

$$

SHORT TERM...MMM
LONG TERM....MMM
AVIATION...Tran