Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX

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936
FXUS64 KEWX 221127
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
627 AM CDT Tue Apr 22 2025

...New AVIATION...

.SHORT TERM...
(Today through Wednesday)
Issued at 111 AM CDT Tue Apr 22 2025

Key Messages:

- Very humid and warm conditions will rule with returning low to
medium (20-60%) rain and thunderstorm chances

- There is a level 1 to 2 out of 5 risk for severe thunderstorms
late this afternoon through tonight across the southern Edwards
Plateau and western Hill Country

Rapid dew point recovery is ongoing across the region as a front
slides northward as a warm front, and with the southeasterly low-
level flow in wake of the boundary. With the returning low-level
moisture, low stratus will quickly establish and expand over the
region by sunrise. Patchy fog will become possible as well across
portions of the coastal plains, southern Edwards Plateau and the
western Hill Country. Isolated low topped showers below the cap
could also establish this morning as well in those areas. With
daytime heating this afternoon, the potential could exist for
isolated to widely scattered storms to develop across the area.
However, not all short term models show the local development of
storms this afternoon with either too much capping or the lack of
enough forcing. The primary region where storms are more likely
develop will be across West Texas and Mexico from late this
afternoon through the evening with the closer proximity of the
dryline and the higher terrain influence. While short term models
lack any good consistency on movement and placement, storms could
attempt to make a run across the Rio Grande sometime around or
beyond sunset. Additionally, the activity across West Texas, may
also attempt to congeal into a single mesoscale convective system
that could slide southeastward towards and into the region from
tonight into early Wednesday. The environment with MLCAPE in the
1500 to 2500 J/kg range and deep layer bulk shear around 35 to 40
knots is enough to support severe thunderstorms. The latest SPC
convective outlook has added a level 2 of 5 risk across Val Verde
County while a level 1 of 5 risk extends eastward into the Hill
Country and south along the Rio Grande into Maverick County. The
primary hazards are large hail and damaging winds. However, any
storms will also be capable of locally heavy rain and frequent
lightning as well.

The rain/storm chances Wednesday will be highly dependent on the
evolution of the storms today through tonight. If a mesoscale
convective complex does move through the region, it may zap the
available instability and overwork the atmosphere. This would
decrease storm chances. Otherwise, if local instability does
maintain, then shower and thunderstorms could develop with the
daytime heating. At this time, Wednesday`s forecast calls for
medium  (30 to 60 percent) chances for rain and storms.

High temperatures will top out from the mid to upper 80s for the
majority to the low to mid 90s along the Rio Grande. Expect the
overnight lows tonight to only fall to the mid 60s to near 70
degrees. The highs on Wednesday become dependent on if a storm
complex moves across the region or now as well. If so, then the
highs will trend lower. For now, the forecast calls for highs
into the low to upper 80s area wide.

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 111 AM CDT Tue Apr 22 2025

Key Messages:

- Chances for showers and thunderstorms continue Wednesday night
  through Friday.

The western part of the country will be under a broad, shallow upper
trough at the start of the long term period. Winds will be from the
southwest. Southwesterly upper flow will continue through the end of
the work week. Beneath this upper pattern the low level flow will be
from the southeast during the same time period. This will keep a
warm, moist airmass in place over South-Central Texas. Forecast
soundings showing this airmass to be conditionally unstable with a
good cap above the boundary layer. Models are in good agreement that
the dryline over West Texas will stay out there. So any convection
will likely be driven by upper level shortwave troughs moving through
the pattern or weak outflow boundaries left over from earlier
convection. This will lead to a forecast problem best solved in the
short term. Thus we are left with broad areas of 30%-60% PoPs each
day Thursday and Friday. Given the forecast situation, these PoPs can
best be thought of as coverage since there are no foci for
convection. There will also be some chance that if storms can form
they could be strong to severe. By the weekend an upper level ridge
will build over Texas from the south. This will end any chances for
rain starting Saturday night and continuing through the end of the
period. Temperatures will warm over the weekend reaching the upper
80s to lower 90s by Sunday and adding a couple of degrees Monday.

&&

.AVIATION...
(12Z TAFS)
Issued at 615 AM CDT Tue Apr 22 2025

Low stratus has built across the region with MVFR to IFR ceilings.
Patchy fog may also develop over portions of the southern Edwards
Plateau and western Hill Country. Conditions improve back to VFR
levels this afternoon. There may be a few weak low topped rain
showers this morning otherwise rain chances are low end this
afternoon. Better chances of scattered showers and storms will be
expected this evening into tonight. There is low confidence with
placement and timing of activity. Have elected to maintain the
PROB30s featuring -TSRA tonight into Wednesday morning at each of
the TAF sites. KDRT has the slightly earlier start as storms may
approach the Rio Grande from Mexico by around 00Z. Low stratus
otherwise returns overnight with MVFR to IFR ceilings. Winds will
generally remain light to moderate from the east-southeast and
southeast through the period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              88  69  84  69 /  20  30  60  20
Austin Bergstrom Intl Airport  89  68  84  68 /  20  30  60  20
New Braunfels Muni Airport     88  68  84  69 /  20  30  50  20
Burnet Muni Airport            87  67  82  68 /  20  40  50  30
Del Rio Intl Airport           89  70  85  72 /  20  40  20  40
Georgetown Muni Airport        89  68  83  68 /  20  30  60  30
Hondo Muni Airport             88  68  84  68 /  20  30  40  20
San Marcos Muni Airport        88  68  84  68 /  20  30  60  20
La Grange - Fayette Regional   88  70  84  70 /  30  30  60  20
San Antonio Intl Airport       88  69  83  71 /  20  30  50  20
Stinson Muni Airport           89  70  85  71 /  20  30  40  10

&&

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

$$

Short-Term...Brady
Long-Term...05
Aviation...Brady