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000
FXUS64 KEWX 251117
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
617 AM CDT Thu Apr 25 2024

...New AVIATION...

.SHORT TERM...
(Today through Friday)
Issued at 236 AM CDT Thu Apr 25 2024

Low clouds and breezy southerly flow continues across South-Central
Texas overnight with cloudy conditions, wind speeds near 15 to 25
mph and mild temperatures in the lower 70s. As the low-levels
saturate further into the morning hours, we are likely to see some
patchy areas of drizzle and perhaps some fog mainly around the I35
corridor and Hill Country. Not likely to see much in the way of
accumulations from this activity other than possible trace amounts
to a few hundredths of an inch. Cloud cover is expected to hold on
throughout the day today but with continued southerly flow, expect
temperatures today to warm into the lower 80s to near 90 degrees
across the area.

The focus for any appreciable thunderstorm chances is towards the
west later today. The dryline is expected to remain west of Val
Verde County today with some high-res models showing convective
initiation well northwest of our area during the late evening hours.
There is a smaller chance of a storm developing west of the the Rio
Grande with a small chance of moving east into the CWA in the
evening hours. Overall chances of this are low but will mention some
silent 10 PoPs in the west through the evening hours. The slightly
better chances for rainfall in our CWA will come after midnight and
closer to daybreak as that activity mentioned earlier developing
near the dryline to our northwest possible makes it into the western
Hill Country before decaying and dissipating. Will mention some 20-
30 PoPs in the Edwards Plateau and Hill Country for this possible
scenario. Can`t completely rule out a strong storm but during the
late afternoon and overnight period from the mentioned
possibilities, but overall chances are 5 percent or less. Lows
tonight will be in the upper 60s to lower 70s across the area once
again.

On Friday, a weak shortwave should help induce some shower and
possible thunderstorm activity across the area. Most of the high-res
guidance shows this activity as showers as a decent cap above 800 mb
is evident in the forecast soundings. The cap is weaker for our
northern counties and will leave the mention of thunderstorms in
addition to the showers there. Rain amounts are not expected to be
too high generally less than 0.2` for most locations. The coverage
of the shower and thunderstorm activity will be diminishing after
21z as the 850-700mb layer dries out a bit as winds become more
southwesterly in that layer. If any updrafts can become sustained
within in the afternoon hours, can`t rule out an isolated strong to
severe storm in the noon-5 pm time frame for mainly our northern
areas where the cap is weakest and the environment would be
supportive of organized convection. Otherwise, highs will top out in
the lower 80s to middle 90s with the warmer temperatures in the
drier airmass near the Rio Grande.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 236 AM CDT Thu Apr 25 2024

Another upper level low is forecast to dig into the Four Corners
Friday night and take a track northeast through the Rockies and into
the central and northern Plains over the weekend. The dryline
retreats back west Friday night, with any remaining isolated
convection dissipating overnight. Patchy drizzle and isolated
streamer showers are possible Saturday morning beneath the cap along
and west of the I-35 corridor. Otherwise, warm, breezy and humid
Saturday east of the dryline and hot near the Rio Grande where drier
air is in place. High temperatures Saturday along the Rio Grande are
forecast to reach the upper 90s to near 100. The hot temperatures
and low humidity in the afternoon could lead to elevated fire weather
conditions across this region. Wind speeds should be weaker in the
afternoon across this region than farther east, but are forecast to
increase Saturday evening, when a brief period of near-critical fire
weather conditions will be possible before relative humidity
recovers with surging dew points.

Attention turns to Saturday night along the dryline located across
west-central Texas and into the southern Edwards Plateau. As forcing
in the tail end of the aforementioned upper level disturbance
approaches, convective initiation is expected along the dryline to
the north late Saturday afternoon and early evening. Convection is
forecast to unzip south into the southern Edwards Plateau late
evening assisted with the low level jet increasing to around 40-50KT
into a cold front catching up with the dryline as well as large scale
ascent increasing. Forecast soundings across portions of the
northern Hill Country and southern Edwards PLateau are favorable
initially for a few severe supercells, with large hail, damaging wind
gusts, and an isolated tornado all threats. Convection may congeal
and become linear overnight through the Hill Country, and potentially
decay/weaken into the I-35 corridor early Sunday morning where it
encounters increasing convective inhibition with the cap. SPC has
placed the Hill Country and portions of the southern Edwards Plateau
and Rio Grande in a Level 2 out of 5 risk for severe storms Saturday
night.

Sunday`s forecast confidence is lower, and conditional on how far
east any complex of storms and the surface dryline/cold front
makes it Saturday night. Generally higher rain chances Sunday will
be located along and east of I-35

The forecast next week is very low confidence. There is a large
spread in the global models, but generally low rain chances are in
the forecast every day, potentially increasing Wednesday into
Thursday.

&&

.AVIATION...
(12Z TAFS)
Issued at 613 AM CDT Thu Apr 25 2024

MVFR stratus remains in place across the area with some pockets of
IFR around the area. Starting to see some radar returns near the San
Antonio sites at the present time and will continue to mention some
light drizzle at the San Antonio sites. Should see some improvement
to VFR by the early afternoon with breezy southerly flow at the
surface. Another round of nocturnal stratus is expected tonight with
MVFR or IFR ceilings. Scattered showers and perhaps a thunderstorm
will be possible as well for the I35 sites tomorrow morning into the
early afternoon hours.


&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              84  71  84  71 /  20  10  60  10
Austin Bergstrom Intl Airport  84  72  83  70 /  20  10  60  10
New Braunfels Muni Airport     85  72  86  70 /  20  10  40  10
Burnet Muni Airport            81  69  82  69 /  10  30  60  10
Del Rio Intl Airport           90  74  96  73 /  10  10   0   0
Georgetown Muni Airport        83  71  82  70 /  20  10  70  10
Hondo Muni Airport             88  71  88  70 /  10  10  30  10
San Marcos Muni Airport        84  71  84  70 /  20  10  50  10
La Grange - Fayette Regional   84  72  84  73 /  10   0  30  10
San Antonio Intl Airport       85  72  85  71 /  20  10  40  10
Stinson Muni Airport           87  72  87  72 /  20  10  40  10

&&

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

$$

Short-Term...29
Long-Term...76
Aviation...29