Austin, Texas 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

516
FXUS64 KEWX 281731 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1231 PM CDT Wed May 28 2025

...New AVIATION (18Z TAFS)...

.SHORT TERM...
(Today through Thursday)
Issued at 122 AM CDT Wed May 28 2025

Key Messages:

- Severe Thunderstorm Watch through 8 AM along the Rio Grande, with
  large hail and damaging wind gusts primary threats along with
  pockets of heavy rainfall leading to isolated instances of flooding.
- Level 2 out of 5 risk for severe storms late this afternoon and
  evening across Llano, Burnet, and Williamson County with large hail
  the primary threat and isolated instances of flooding.

Convective chances through the overnight and during the day on
Wednesday will be highly driven by mesoscale features. Thunderstorms
currently moving through the southern Edwards PLateau and far
northern Hill Country are riding along a stalled frontal boundary.
CAMs generally indicate this weakening as it moves into the northeast
Hill Country and Central Texas early this morning. Farther south, a
complex of storms coming out of Mexico into southern Maverick and
Webb counties has generated a MCV. The MCV is in the process of
pivoting into far southern Maverick and Dimmit counties and could
result in damaging wind gusts and large hail, along with heavy
rainfall. This complex is indicated by most cams to track east into
South Texas through the overnight hours. In between, we have finally
seen some upscale growth of storms across northern Coahuila that are
tracking into Val Verde County. CAMs don`t have a good handle on
this, and there is uncertainty with how much this fills in between
the MCV to the south, which could cut off richer inflow, and storms
in the far northern Hill Country. The forecast currently calls for at
least scattered activity pivoting into the I-35 corridor and Coastal
Plains pre-dawn through the morning hours. The afternoon forecast is
much lower confidence, highly conditional on what plays out the next
6-12 hours.

Also, we will be watching another cluster of storms late afternoon
to the northwest, indicated by several CAMs to come out of west-
central Texas southeast into at least Llano, Burnet, and Williamson
counties late afternoon into the evening. A Level 2 out of 5 risk for
severe storms is forecast across or near these counties, with large
hail the primary threat and pockets of heavy rainfall. This activity
is forecast to weaken after sunset as it moves southeast.

Northwest flow aloft continues into Thursday, but lack of surface
features, and the next front still north of the region, indicates
convective coverage would be isolated at best.

&&

.LONG TERM...
(Thursday night through Tuesday)
Issued at 122 AM CDT Wed May 28 2025

Key Messages:

- Active weather pattern continues through the week with rain/storm
chances and slightly cooler temperatures.

On Thursday night, a deep-layer trough over the Midwestern US is
expected to amplify and rotate east, producing a flow that favors
the southward push of a frontal boundary from North Texas into our
area. Northwesterly to west-northwesterly flow at 500mb with a
proclivity for shortwave progression along the broader trough
encountering moderate to high instability (especially earlier
Thursday evening) will support chances for at least isolated showers
and thunder, with adequate deep-layer wind shear along the front to
support some severe potential. However, there are significant
uncertainties concerning convective coverage, with the possibility
of pre-frontal activity along the Coastal Plains and I-35 corridor
potentially throwing a wrench into the setup. In turn these
uncertainties will affect timing and progression of the front
through our area Thursday night into Friday morning. For now, rain
chances during the overnight period are held at about 20 to 30
percent, favoring the northwestern half of our CWA along the slow-
moving front.

Mid-level ridging quickly wedges in behind the outgoing trough, so
the post-frontal airmass looks to give only a glancing pass of South-
Central Texas. The upper-air arrangement is more conducive to the
front stalling and washing out or reversing course over our area.
Lingering cloud cover is expected Friday, along with low chances for
isolated showers mainly closer to the Rio Grande where veering flow
behind the front is most favorably positioned for isentropic upglide
both during the day and overnight. High temperatures during the day
look to settle generally in the 80s for the most... a slight
downtick from Thursday, accompanied by slightly lower moisture
courtesy of the post-frontal air.

Surface high pressure briefly swings over East Texas Friday night
into Saturday, bringing low temperatures in the mid-60s north of I-
10. While the upper-air pattern over CONUS would typically support a
quieter Saturday with large-scale subsidence for our area, mid-level
moisture from a possible recurving and yet-to-develop tropical
cyclone over the Eastern Pacific may stream into or near our area as
a cut-off low over the Baja California provides a corridor of
southwesterly mid-level winds. The general synoptic setup better
favors the bulk of this moisture passing to our south over deep
South Texas, but a more amplified and closer cut-off low could
foreseeable drive more of this moisture into our region and increase
rain chances. The evolution of the synoptic pattern and where the
tropical disturbances consolidates and tracks will ultimately guide
where the moisture is distributed, and could influence our weather
through Sunday.

Heading into next week, amplifying large-scale troughing is
anticipated over the Western CONUS, which should lead to a
strengthening of southerly flow over South Central Texas and provide
opportunities for shortwave disturbances to spark occasional rounds
of thunderstorms Monday and perhaps again Tuesday. This return flow
looks to also promote an increase in daytime highs back into the
90s.

&&

.AVIATION...
(18Z TAFS)
Issued at 1225 PM CDT Wed May 28 2025

A somewhat tricky forecast for this evening as thunderstorm coverage
is uncertain and confidence in timing and extent is low. Will opt for
PROB30s to cover this uncertainty at AUS, SAT, and SSF with generally
light winds less than 10 kts through the period. MVFR ceilings are
expected to develop late tonight over all sites and even closer to
sunrise at DRT. Otherwise, have kept the forecast dry for Thursday
but PROB30s may need to be utilized in future forecasts once again
for storm chances if confidence increases.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              70  90  71  86 /  30  20  20  20
Austin Bergstrom Intl Airport  68  90  69  85 /  30  30  20  20
New Braunfels Muni Airport     70  90  71  87 /  20  20  10  20
Burnet Muni Airport            68  88  68  83 /  30  20  20  20
Del Rio Intl Airport           74  93  75  91 /  20   0  30  40
Georgetown Muni Airport        68  88  68  81 /  40  20  20  20
Hondo Muni Airport             70  92  72  87 /  20  10  10  20
San Marcos Muni Airport        69  90  71  86 /  20  20  10  20
La Grange - Fayette Regional   70  88  72  86 /  20  30  10  20
San Antonio Intl Airport       72  90  73  88 /  20  20  10  20
Stinson Muni Airport           73  91  75  89 /  20  20  10  20

&&

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

$$

Short-Term...76
Long-Term...Tran
Aviation...MMM