Llano, Texas Weather Forecast Discussion

155
FXUS64 KEWX 211741
AFDEWX
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1241 PM CDT Sun Sep 21 2025
.KEY MESSAGES...
- Above normal temperatures continue, culminating with late
  season triple digit heat on Tuesday.
- Confidence increasing in rain chances Tuesday through Thursday
  (currently 20-60%).
- Possible active pattern returns late September/early October.
&&
.SHORT TERM (THROUGH MONDAY NIGHT)...
The seabreeze has picked up steam this afternoon as showers and
isolated thunderstorms develop over the middle Texas coast. Some
of this activity is expected to push off some outflow which may
allow showers to develop as far west as the I-35 Corridor this
afternoon and early evening before all activity weakens with
loss of diurnal heating.
Monday will be yet another hot day with highs in the 90s area
wide. Mid-level ridging will strengthen a bit on Monday as
the high moves a bit further north and east. That should put a
cap on any seabreeze activity moving as far inland as the I-35
Corridor. Still, the Coastal Plains should see some activity
Monday afternoon.
&&
.LONG TERM (TUESDAY THROUGH SUNDAY)...
Our eyes remain fixed on a cold front that continues to get
pushed back, but may have finally settled on an early Wednesday
passage. Before it gets here though, compressional warming and
mid-level ridging ahead of the approaching 500mb trough will
lead to hopefully the last truly hot day of the Summer/early
Fall season. Temperatures will climb into the upper 90s to
around 101-102 Tuesday afternoon, particularly over the Rio
Grande Plains and I-35 Corridor. We may be getting close to Heat
Advisory criteria, but it would still be rather sparse given
heat indices mostly less than 108. Still, it`ll be a very hot
afternoon as well as a humid one.
The cold front should finally start moving into the region on
Wednesday morning, with a peak in convection expected Wednesday
afternoon during peak heating over the region. Showers and
storms could become heavy late Wednesday evening as they move
south through the southern half of the CWA. It`ll provide
welcome relief from the heat, but the cooldown behind this front
will be more felt in the mornings than the afternoons.
Temperatures should fall to the 60s for most in the mornings
with afternoons in the mid to upper 80s and lower 90s Thursday
through next Sunday.
Beyond this forecast period, increased moisture from the Pacific
and a deepening trough over the western CONUS will result in a
more active pattern for late September and early October.
&&
.AVIATION (16Z SUNDAY THROUGH MONDAY)...
VFR conditions will prevail through the afternoon and evening with a
scattered cumulus field. There is a 20-40% chance of isolated SHRA
20Z-01Z this afternoon and early evening across the Coastal Plains
and 10-20% near the I-35 corridor. Stratus is forecast to develop
overnight and early Monday morning along the escarpment, producing
MVFR ceilings at SAT/SSF/AUS. This will scattered out late Monday
morning.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              74  97  76  99 /   0  10   0  10
Austin Bergstrom Intl Airport  74  97  75 100 /   0  10   0  10
New Braunfels Muni Airport     72  97  74  99 /  10  10   0  10
Burnet Muni Airport            72  93  74  96 /   0   0   0  10
Del Rio Intl Airport           76  98  77  99 /   0   0   0   0
Georgetown Muni Airport        73  96  74  98 /   0   0   0  10
Hondo Muni Airport             71  96  73  99 /   0   0   0  10
San Marcos Muni Airport        72  97  73  99 /  10  10   0  20
La Grange - Fayette Regional   73  94  74  97 /  10  20   0  30
San Antonio Intl Airport       75  96  76  99 /   0   0   0  10
Stinson Muni Airport           75  98  77 100 /   0   0   0  10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...MMM
LONG TERM...MMM
AVIATION...76

NWS EWX Office Area Forecast Discussion