Concrete, Texas Weather Forecast Discussion

279
FXUS64 KEWX 221921
AFDEWX
Area Forecast Discussion
National Weather Service Austin/San Antonio TX
221 PM CDT Mon Sep 22 2025
.KEY MESSAGES...
- The heat continues through Tuesday across all of south
  central Texas.
- A cold front brings temperature relief to some areas Wednesday
  along with rain chances into Thursday.
&&
.SHORT TERM (THROUGH TUESDAY NIGHT)...
A stable pattern regarding the large-scale flow remains intact
through Tuesday with the mid and upper level subtropical high
over central and northern Mexico remaining the dominant weather
feature. Little change in the air mass will result in continued
above normal high and low temperatures for the first couple days
of the Fall season. The NBM guidance has been a little low with
regards to temperatures, so we will nudge the NBM values upward
to account for this trend. The heat combined with continued
southerly flow in the lower levels may push afternoon heat index
values close to 108 degrees in the coastal plains on Tuesday.
We also expect to see a few showers and storms today from the
coastal plains to near the I-35 corridor. The last few runs of
the HRRR are highlighting a small area (Burnet, Blanco & Kendall
counties) over the Hill Country for some possible showers and
storms today. We have updated the forecast to add a low chance
for some afternoon convection today. For Tuesday, we will keep
rain chances confined to near the coastal plains given any lift
will be limited to the sea breeze.
&&
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
An increase in mid and upper level troughing across the southern
plains states will bring a change to our weather pattern
beginning Wednesday. A cold front will accompany the above
mentioned weather system, but some timing differences are noted
among the global and hi-res models. Will tend to side with the
faster southward movement of the front on Wednesday, with some
relief from the hot temperatures in store from the southern
Edwards Plateau eastward into the Hill Country and I-35 corridor
from Austin northward. Farther south, the heat will likely
continue for one more day as highs top out in the mid to upper
90s along and south of U.S. Highway 90.
While our region will be on the southern edge of where the
stronger forcing for ascent will reside, we do expect to see a
good chance for rain across south central Texas as the front
makes steady southward progress during the daytime hours on
Wednesday. A few strong storms will be possible, especially
during the afternoon hours, generally along and south of a Del
Rio to San Marcos to Giddings line. The flow aloft will be
fairly weak across south central Texas, so any concerns for
strong storms will likely be relegated to the peak heating hours
as the front drops southward. Given little shear, the main
severe weather concern would be for locally strong wind gusts.
We will also see some enhanced moisture levels along and just
behind the boundary, so some locally heavy rainfall will be
possible for areas generally along and south of a Pearsall to
Hondo to Austin line. At this time, it does not look like a
widespread, heavy rain event. However, some pockets of heavy
rain can be expected given the front, enhanced moisture and
slow-moving storms.
Drier and cooler air in the lower levels will filter in behind
the boundary on Thursday and this will bring a decreasing chance
of rain from north to south as the day progresses. All areas can
finally expect a break from the heat on Thursday as highs
generally top out in the 80s under partly to mostly cloudy
skies.
Dry weather develops behind the front on Friday into Saturday as
mid and upper level ridging briefly develops over the region.
We will keep a low chance for showers in the forecast across the
southern Edwards Plateau Saturday afternoon as southwesterly
flow aloft begins to develop to our west. Through the remainder
of the forecast, the current round of GFS and ECMWF ensemble
guidance both show an upper low developing over the desert
southwest or southern California. Moisture levels associated
with this pattern appear to remain higher out west along the Rio
Grande, so we will keep some low rain chances in the forecast
for this area as we head into early next week. High temperatures
are expected to stay at or just above normal, while overnight
lows will likely stay below normal for most areas, except out
west along the Rio Grande.
&&
.AVIATION (18Z MONDAY THROUGH WEDNESDAY)...
MVFR ceilings have finally lifted at SAT and SSF with VFR expected
through the remainder of the day. Winds will start more southerly
early this afternoon and switch to southeasterly by late evening and
overnight, ushering in additional low level moisture, resulting in a
return to MVFR ceilings after 08Z at AUS, SAT, and SSF. DRT should
remain VFR but there is a low chance MVFR could develop briefly
after sunrise. Otherwise, VFR ceilings return by mid to late morning
Tuesday followed by an increase in south to south-southwesterly
winds Tuesday afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              76 100  76  93 /  20  10  20  70
Austin Bergstrom Intl Airport  75  99  76  93 /  20  10  20  70
New Braunfels Muni Airport     74  99  75  95 /  20   0  10  70
Burnet Muni Airport            74  95  74  85 /  20   0  30  70
Del Rio Intl Airport           78  99  78  95 /   0   0  10  50
Georgetown Muni Airport        75  98  75  89 /  20   0  30  70
Hondo Muni Airport             74  98  74  95 /   0   0  10  60
San Marcos Muni Airport        74  99  74  95 /  20  10  10  70
La Grange - Fayette Regional   74  96  75  93 /  20  20  10  80
San Antonio Intl Airport       76  99  77  95 /  10   0  10  60
Stinson Muni Airport           77 101  77  98 /  10   0  10  60
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Platt
LONG TERM...Platt
AVIATION...MMM

NWS EWX Office Area Forecast Discussion