193
FXUS64 KEWX 211041
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
541 AM CDT Tue Jul 21 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 538 AM CDT Tue Jul 21 2026

- The Nueces and Frio River Basins continue to see Major-to-
  moderate river flooding and while water levels in most rivers
  remain high, expect steady improvement over the coming days.

- High temperatures will continue to intensify through the middle of
  the week. Heat index values will be highest on Wednesday and
  Thursday, particularly along and east of I-35.

- Tropical Storm Bertha has formed in the northeast Gulf and will continue
  to slowly push westward through the week. We are keeping a
  close eye on this system for any potential impacts to our
  region.

&&

.SHORT TERM...
(Today through Wednesday)
Issued at 1217 AM CDT Tue Jul 21 2026

Upper-level low over western Texas will continue to push westward
and should be out of our area by early Tuesday morning. In response,
upper-level ridging will be able to take further hold on the region.
This will bring a hot and generally rain-free pattern through the
middle part of the week. Subsidence should continue to suppress any
convection while simultaneously helping temperatures to climb into
the upper 90s to around 100 degrees today. The exception will be for
portions of the Southern Edwards Plateau, where temperatures could
remain closer to the lower and mid 90s. Max heat index values on
Monday were pretty close to (if not lower in some locations where
some much lower dewpoints settled in) what we had in the forecast.

That being said, heat index values will be higher across the region
for today, with most of the area reaching the 100 degree mark this
afternoon. After seeing how things trended Monday, I am going to
hold true to what we have in there for today and will elect not to
issue a Heat Advisory at this time. This does not mean a few places
might briefly reach 108 degrees, but it is not widespread enough for
me to have enough confidence to issue one. Wednesday will easily be
the warmest day of the week, especially for the Rio Grande Plains
and areas along and east of the I-35 corridor where afternoon highs
will reach into the lower 100s to some areas hitting the middle
100s. We will see an increase in mid-level moisture on Wednesday,
which will help max heat index values to reach Heat Advisory
criteria levels.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 1217 AM CDT Tue Jul 21 2026

We could see some expanding of a potential Heat Advisory across more
of the region for Thursday and heat index values will once again
reach that critical threshold of 108 degrees although ambient
temperatures will be slightly lower than that on Wednesday. Right
now it will be tough to pinpoint much else in way of temperatures
for the rest of the week as we continue to monitor what is now
Tropical Storm Bertha. Bertha became a little more organized between
normal advisory times, so a special advisory was issued to name it.
What we do know, Bertha will bring some Tropical Storm conditions to
portions of the Gulf Coast from Alabama westward to southeastern
Louisiana. What we don`t know, is how this system will impact our
area. Right now trends are shifting the track a little further to
the north, which would be good for limiting the impacts we see here
in Texas. What you should do, continue to monitor the forecast for
the latest information as things could change throughout the next
few days. Otherwise, temperatures will remain elevated and near or
above normal through the long-term period and mostly dry conditions
(Tropical Storm Bertha dependent) will remain in place for our
region.

&&

.AVIATION...
(12Z TAFS)
Issued at 538 AM CDT Tue Jul 21 2026

VFR conditions are forecast to prevail across the local area
terminals through this cycle. Southerly wind flow of 5 to 10 knots
are forecast through the period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry             100  80 102  83 /   0   0   0   0
Austin Bergstrom Intl Airport  99  79 101  82 /   0   0   0   0
New Braunfels Muni Airport     98  77 101  81 /   0   0   0   0
Burnet Muni Airport            99  78 101  80 /   0   0   0  10
Del Rio Intl Airport           97  75  99  77 /   0   0   0   0
Georgetown Muni Airport       100  81 102  82 /   0   0   0   0
Hondo Muni Airport             97  75  99  80 /   0   0   0   0
San Marcos Muni Airport        99  77 101  81 /   0   0   0   0
La Grange - Fayette Regional  101  77 103  82 /   0   0   0   0
San Antonio Intl Airport       98  78 100  83 /   0   0   0   0
Stinson Muni Airport           97  78 100  82 /   0   0   0   0

&&

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

$$

SHORT TERM...17
LONG TERM....17
AVIATION...17