558
FXUS64 KEWX 300931
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
431 AM CDT Thu May 30 2024

...New AVIATION...

.SHORT TERM...
(Today through Friday)
Issued at 200 AM CDT Thu May 30 2024

A weak impulse has allowed for some isolated to scattered convection
to move into Maverick County overnight and this activity should push
southeast of the CWA shortly. Elsewhere, southeast winds are in
place across the area with an abundance of high clouds associated
with distant convection. Should begin to see some low-clouds develop
later tonight. Temperatures are in the upper 70s to lower 80s and we
will likely see low temperatures later tonight bottom out near 70 to
the upper 70s with the cooler temperatures expected in the Hill
Country. Most of the day should remain quiet but will carry some low
PoPs in the eastern counties. There is a boundary near Houston that
is slowly working west and this could provide some focus for shower
and storm activity during the today period. High temperatures today
will be similar to yesterday, topping out near 90 in the north to
near 100 along the Rio Grande.

The main focus for convection in the short-term will be during the
tonight period. CAMs are fairly consistent that thunderstorms will
develop in West Texas and the Panhandle along the dryline. However,
there are some differences between the members of the short-term
guidance about the overall evolution of any potential MCS once
storms develop and potentially transition into an MCS as the cold
pools become dominant. The ARW sends the system into the CWA early,
while the FV3/NAM keep the system a bit later and weakening as it
enters the CWA. The 00z HRRR has the MCS entering the Hill Country
around 1-2am and does keep it ongoing through daybreak Friday. Will
show PoPs in the 30-60 percent range tonight with the higher PoPs in
the Hill Country where probabilities are high that some sort of
effect from the system is likely. The latest Day 1 Outlook from SPC
has most of the CWA at least in a Level 1 (marginal) risk of severe
storms with a Level 2 (slight) risk in the northern Hill Country.
This seems reasonable as this area is most likely to see some sort
of impact from the potential MCS with the main question being the
overall strength of it by the time is enters the CWA. The main risk
with any storms will be damaging winds but hail and perhaps an
isolated tornado cannot be ruled out. Lows tonight will likely be
near 70 in the Hill Country ranging up to the upper 70s in the west
and southern counties. Lows will likely be influenced by convection
with potential rain cooling to the surface.

The forecast Friday will definitely be impacted by what occurs
tonight. Models that show decent widespread convection tonight show
little convection during the day on Friday as the atmosphere will
likely be pretty well worked over. Will undercut the elevated NBM
PoPs for now as we lean more to that solution. Highs Friday will be
in the upper 80s to upper 90s across the region.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 200 AM CDT Thu May 30 2024

The unsettled weather pattern continues at least through the first
half of the weekend. The timing and location of each round of rain
and storms will remain difficult to pinpoint and ultimately depends
on how well the atmosphere recovers from the previous rounds of
storms and/or outflow. The same general triggers for storms remain
in place across the state. This includes shortwave disturbances
embedded within the west-northwesterly mid-level flow above the
upper level ridge centered across Mexico, the dryline towards the
west, a lingering surface front to the north, and any remaining
outflow boundaries from previous rounds of convection. Storms will
be capable of becoming strong to severe with any round from the
result of moderate to strong instability and sufficient deep layer
shear profiles over the area. Storms will be capable of heavier
rainfall rates as well and could pose a risk of flooding pending
previous rainfall, speed of storms, and antecedent soil moisture.
Temperatures will continue to run a little above climatological
average through the weekend.

Medium range guidance, including the ensemble means, continue to
indicate some decline of the area rain chances and an increase in
the heat next week as the upper level ridge centered over Mexico
builds northward and transitions toward an Omega Block pattern.
Given that the ridge becomes more centered to our west, the flow
aloft turns more northerly across South-Central Texas. While the
rain chances generally do look to lessen, this is not expected to
completely eliminate them out of the forecast as that northerly
steering flow could help promote the approach of outflow and/or an
upper level disturbance or two advancing out of the central and
southern plains along the eastern periphery of the ridge. Some
guidance indicates this potential toward the middle of next week.
Afternoon highs climb back to the mid 90s for many near the I-35
corridor and up into the 100 to 105 degree range along the Rio
Grande. With the dew points forecast to remain elevated, the heat
indices could approach and/or reach Heat Advisory levels across
portions of the region at times next week. Overnight lows remain
elevated in the 70s to near 80 degrees as well.

&&

.AVIATION...
(12Z TAFS)
Issued at 428 AM CDT Thu May 30 2024

MVFR stratus is in place across most of the area this morning with a
pocket of IFR for AUS. Should see these restrictions continue
through at least the late morning hours before VFR returns. Another
round of MVFR ceilings and some possible showers and thunderstorms is
expected tonight. Will include PROB30 groups for now to cover the
threat for the storms and prevail the restrictions,

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              91  73  89  74 /  20  50  40  30
Austin Bergstrom Intl Airport  91  72  88  74 /  20  50  40  30
New Braunfels Muni Airport     95  74  92  74 /  20  50  30  30
Burnet Muni Airport            89  71  84  72 /  20  60  40  30
Del Rio Intl Airport          100  79  98  78 /  10  20  10  20
Georgetown Muni Airport        89  70  87  72 /  30  50  50  30
Hondo Muni Airport             96  75  94  75 /  10  40  20  30
San Marcos Muni Airport        93  72  91  74 /  20  50  40  30
La Grange - Fayette Regional   90  74  88  75 /  30  40  40  30
San Antonio Intl Airport       94  74  92  76 /  10  40  30  30
Stinson Muni Airport           96  76  94  76 /  10  40  30  30

&&

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

$$

Short-Term...29
Long-Term...Brady
Aviation...29