511
FXUS64 KEWX 121758
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1258 PM CDT Sat Sep 12 2026

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

.KEY MESSAGES...
Updated at 1252 PM CDT Sat Sep 12 2026

- Heat Advisory in effect through 7 PM for areas generally along
  and east of the Interstate 35 corridor. Above normal
  temperatures will persist into early next week, with additional
  heat headlines possible.

- Low chance (15 percent) for isolated thunderstorms this
  afternoon and evening from the Hill Country east.

- Most areas remain dry into next week, except for some low rain
  chances over the coastal plains.

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 1252 PM CDT Sat Sep 12 2026

Lingering cloud cover over the portions of the I-35 corridor and
coastal plains provided a "cooler" start to the day than seen
yesterday, though temperatures are still expected to climb into the
upper 90s and triple digits later this afternoon. Highs were lowered
about a degree over the I-35 corridor but we are still expecting
heat index values to rise into the 108-111 degree range for a good
portion of the Heat Advisory area which remains in effect through 7
PM.

Ridging continues to build over the area today from the west which
will limit the coverage of storm development this afternoon and
evening. That said, hi-res guidance continues to indicate at least a
few isolated showers or thunderstorms today aided by peak heating.
If a few storms develop, the main focus will be from the Hill
Country and locations to the east. Have capped the PoPs at 15
percent due to the isolated nature of any activity.

The elongated ridge will be over North Texas Sunday keeping rain
chances low again (mainly limited to the coastal plains) and
temperatures hot. Highs should decrease slightly for tomorrow but no
hover near Heat Advisory levels. With more sparse coverage for Heat
Advisory conditions expected at this time, have held off on any
product issuance for Sunday but we will continue to monitor for the
I-35 corridor and coastal plains.

&&

.LONG TERM...
(Monday through next Saturday)
Issued at 1252 PM CDT Sat Sep 12 2026

Above normal temperatures persist next week. An upper level ridge
will be centered northeast of our area Monday through at least the
middle of next week, eventually expanding further west late week.
Highs will continue to range from the mid 90s to slightly above 100
degrees each day through mid-week with heat indices hovering around
the 105-108 degree mark near the I-35 corridor and coastal plains.
Some seabreeze showers and thunderstorms may impact the coastal
plains each afternoon/evening, otherwise expect mainly dry
conditions. The forecast does bring a slight decrease in
temperatures (at least staying below 100 degrees) late week along
with some better coverage of rain chances, but there remains decent
uncertainty in the pattern this far out.

&&

.AVIATION...
(18Z TAFS)
Issued at 1231 PM CDT Sat Sep 12 2026

The forecast remains on track with VFR ceilings expected through
the rest of the afternoon and evening hours. Winds will turn more
southeasterly at AUS by 21Z while they remain southeasterly at
SAT and SSF through the entire forecast period. Have continued
with the PROB30 this afternoon and evening for AUS, SAT, and SSF
to account for the threat for thunderstorms and gusty winds. The
trend is your friend and MVFR ceilings can be expected overnight
first at SAT and SSF followed by AUS then eventually DRT for a
short time.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              78 101  78 100 /  20  10   0   0
Austin Bergstrom Intl Airport  77 100  77  99 /  20  10   0  10
New Braunfels Muni Airport     76 100  76  99 /  20  10   0  10
Burnet Muni Airport            75  97  74  97 /  20  10   0   0
Del Rio Intl Airport           79 101  77 100 /   0   0   0   0
Georgetown Muni Airport        77 100  77  99 /  20  10   0   0
Hondo Muni Airport             75 100  75  99 /  20  10   0   0
San Marcos Muni Airport        76 100  76  99 /  20  10  10  10
La Grange - Fayette Regional   77 100  77  99 /  20  20   0  30
San Antonio Intl Airport       78  99  78  99 /  20  10   0  10
Stinson Muni Airport           78 101  78 100 /  20  10   0  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 7 PM CDT this evening for TXZ173-191>194-
205>209-220>225.

&&

$$

SHORT TERM...27
LONG TERM....27
AVIATION...MMM