958
FXUS64 KEWX 221732
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1232 PM CDT Wed Jul 22 2026

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

.KEY MESSAGES...
Updated at 1230 PM CDT Wed Jul 22 2026

- Major to moderate flooding will continue on the Nueces through the
  remainder of the week while the remainder of the rivers will
  continue to improve.

- Extreme Heat Warning in effect for the Austin Metro and Coastal Plains
  through 8PM this evening, and a Heat Advisory in effect for the
  I-35 Corridor, Hill Country, and Coastal Plains through 8PM
  Thursday.

- Tropical Storm Bertha moves through the Gulf today and tomorrow
  and some tropical downpours are possible, primarily Thursday
  afternoon and evening over the Coastal Plains.

&&

.SHORT TERM...
(Tonight through Thursday night)
Issued at 1230 PM CDT Wed Jul 22 2026

Largely cloud free skies and strong subsidence is noted over South
central Texas early this afternoon. A 596dm Subtropical High is
centered over southwest Oklahoma and will be responsible for our
Extreme heat today and tomorrow and in response to continued very
hot signal, we`ve opted to expand the Heat Advisory both spatially
and temporally. Additionally, an Extreme Heat Warning is now in
effect for the Austin Metro and Coastal Plains as heat indices climb
into the 113-115+ range this afternoon and evening. The NBM has been
handling surface dewpoint fairly well recently and paints a rather
humid picture this afternoon. Dewpoints are unlikely to mix out
significantly, and in combination with ambient air temperatures in
the 100-106 range, heat indices will climb to 108-115+ at times over
most of south central Texas. Winds have been fairly light so far
today, which will limit mixing, and with area soils still fairly
saturated from recent rains (NASA SPoRT LIS 0-100cm soil moisture is
between 75-100% over much of the Edwards Plateau, Rio Grande Plains,
and Hill Country), thinking that models may be slightly
underforecasting dewpoints. Basically, high dewpoints=higher heat
indices. With regard to the Heat Advisory, we opted to extend it
through the overnight hours as near all-time record warm low
temperatures are expected at San Antonio and Austin, with lows in
the 78-83 range. For reference, the all-time warmest low temperature
at San Antonio International is 82 and the warmest lows at Austin
Bergstrom and Austin Camp Mabry are 83 and 84 respectively. We want
to stress heat safety, particularly in areas that are cleaning up
from last weeks flooding as heat illness doesn`t take long in these
conditions, as well as the threat for little to no break from the
humidity and heat in the overnight hours tonight and stretching into
the day Thursday.

Turning our attention to the northern Gulf, Tropical Storm Bertha
remains rather disorganized with a notable convective burst over the
northern Gulf and the storms center located due east of New Orleans
and just to the south of Biloxi, MS. Bertha is currently experience
moderate to high northeasterly shear from the Subtropical Ridge
centered over southwest Oklahoma. This is expected to continue and
keep Bertha on the weaker side through the next 24-36 hours as it
tracks west and slowly weakens over the northern Gulf. The 12Z HREF
members are in fairly good agreement on scattered showers and storms
developing over the Houston CWA this afternoon and early evening and
sliding west. These are expected to weaken as they move west and
encounter more subsidence under the aforementioned ridge. However,
as Bertha starts to work a bit further west and under this ridge,
PWATs should climb back above 2" at times, particularly over the
Coastal Plains and I-35 Corridor overnight and into the day
Thursday. As of the latest 12Z CAMS, concerns for locally heavy
rains with a quick 1-2" possible are over the Coastal Plains, but
could stretch a little further north to the San Antonio metro on
Thursday evening. However, with strong ridging to our north and a
weakening storm moving inland, we are not anticipating significant
rainfall that would lead to any sort of flooding concerns. Some
gusty winds to 30+ mph are also possible in any showers/storms as
they move through the region.

&&

.LONG TERM...
(Friday through next Wednesday)
Issued at 1230 PM CDT Wed Jul 22 2026

Ridging is the predominant feature of the long term period with
mainly hot and dry conditions continuing across South Central Texas.
The exception will be some lingering low rain chances Friday over
the Coastal or Rio Grande Plains associated with the current
Tropical Storm Bertha. Right now, any scattered showers Friday are
expected to only bring meager rain amounts over these areas though
we will need to continue to monitor the track and intensity of
Bertha which could change this forecast. The heat remains intact
through the period with high temperatures this weekend into next
week in the mid and upper 90s. Dew points decrease a bit which will
bring heat indices down slightly, though many locations still will
see maximum values in the 100-105 degree range.

&&

.AVIATION...
(18Z TAFS)
Issued at 1230 PM CDT Wed Jul 22 2026

VFR will prevail through the forecast period at all TAF sites with
generally light winds below 10 knots. MVFR ceilings are expected to
remain well south and east of the TAF sites, with low probabilities
(20% or less) closer to the immediate Texas coast. Some patchy fog
cannot be ruled out as winds become calm to variable below 3 knots
tonight.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              81 100  80  95 /  20   0  30  10
Austin Bergstrom Intl Airport  81  99  80  95 /  20   0  30  10
New Braunfels Muni Airport     81 100  79  95 /  20   0  30  10
Burnet Muni Airport            79  99  78  94 /  10   0  20  10
Del Rio Intl Airport           83 102  79  96 /   0   0   0   0
Georgetown Muni Airport        80  99  80  95 /  20   0  20   0
Hondo Muni Airport             79 100  79  94 /   0   0  20  20
San Marcos Muni Airport        81 100  78  95 /  20   0  30  10
La Grange - Fayette Regional   82  99  79  96 /  20   0  30  10
San Antonio Intl Airport       82 100  80  94 /  10   0  30  20
Stinson Muni Airport           82 100  80  95 /  10   0  30  20

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT Thursday for TXZ171-172-186>191-
203>208-218>224-228.

Extreme Heat Warning until 8 PM CDT this evening for TXZ173-
192>194-209-225.

Heat Advisory from 8 PM this evening to 8 PM CDT Thursday for
TXZ173-192>194-209-225.

&&

$$

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