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000
FXUS64 KEWX 210541
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1241 AM CDT Sun Apr 21 2024

...New AVIATION...

.UPDATE...
Issued at 649 PM CDT Sat Apr 20 2024

A quick update issued to reduce the fog potential and clean up some
of the PoP/WX/Temp/Dew Point trends. San Antonio area continues to
under-perform what the rapid refresh models had in store, but late
evening to around 1 AM should be their best opportunity to get storms
and heavy downpours. A low end severe threat for mainly hail
continues this evening for most areas.

&&

.SHORT TERM...
(Tonight through Sunday night)
Issued at 143 PM CDT Sat Apr 20 2024

We`ll continue to monitor two main areas for additional shower and
thunderstorm development through the afternoon and evening. The
first area is across the Coastal Plains and portions of the I-35
corridor where southerly warm air advection continues around 850mb.
This has already led to the development of some light streamer
showers over the last few hours, and the potential for thunderstorms
will continue to increase due to both increasing lift and
instability in advance of a 500mb shortwave moving in from the west.
The other area we`ll be monitoring is the ongoing convection across
the Big Country which is expected to continue to develop and push
south/east into the Edwards Plateau and Hill Country in the coming
hours. The upper level shortwave and a reinforcing shot of cooler
air at the surface will both push convection south and east across
the area this evening and overnight, with generally dry conditions
expected by the daytime hours Sunday.

As far as the thunderstorms that are expected over the next 12 hours
or so, both shear and instability parameters continue to support a
marginal severe threat (isolated hail and damaging wind gusts).
Additionally, there is a slightly more concerning heavy
rainfall/flash flood threat with PWATs generally ranging from 1.5-
1.7" across south-central Texas. We are not confident that instances
of flooding will be widespread enough to warrant the issuance of a
Flash Flood Watch, but isolated pockets of 3+" inches could cause
some localized issues. While heavy rainfall will be possible with
any thunderstorm, the HREF Probability Matched Mean continues to
favor eastern portions of our CWA for the greatest rainfall amounts.

As mentioned above, the daytime hours on Sunday are looking dry,
though mostly cloudy skies and a decent northeasterly breeze will
make for a chilly day (at least for this time of year) with highs
across northern and eastern areas only in the 60s. Lows will dip
into the 40s and 50s areawide for Monday morning

&&

.LONG TERM...
(Monday through Saturday)
Issued at 143 PM CDT Sat Apr 20 2024

A mid-level ridging pattern establishes much of next week across
South-Central Texas while within the lower levels of the atmosphere
a light to moderate south-southeasterly onshore flow returns with
surface high pressure sliding to the east. With the southerly flow,
steady moisture recovery will be expected through early week as dew
points climb into the mid to upper 60s by Wednesday afternoon. The
dew points remain high through the rest of the period. An uptick in
cloud cover along with occasional stray opportunities for light mist
or drizzle may evolve mid to late week with the low-level moisture
advection coming off the gulf. A pair of upper level systems pushing
into or across the Four Corners region late week into the weekend
could help to induce slightly better opportunities for shower and/or
convection at the end of the forecast period across northeastern
most counties. Some differences exist in the medium range guidance
on these systems but those details will be ironed out with time in
the days ahead. Afternoon highs will steadily rise through the long
term with values into the mid 80s to mid 90s by Friday and Saturday.
Overnight lows also rise back into the 60s and even the low 70s by
the end of the period as well.

&&

.AVIATION...
(06Z TAFS)
Issued at 1237 AM CDT Sun Apr 21 2024

Strong to severe TSRA currently moving through the KSAT/KSSF area
will move east of there by 07Z or 08Z, then slowly weaken.
Otherwise, a mix of LIFR/MVFR CIGs with local reductions to VSBY will
prevail overnight through much of Sunday. CIGs/VSBYs then rise to VFR
later on Sunday. Northerly winds of 10 to 20 KTs with a few gusts to
30 KTs overnight into Sunday, decrease to less than 10 KTs Sunday
night.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              49  73  54  80 /   0   0   0   0
Austin Bergstrom Intl Airport  46  72  51  79 /   0   0   0   0
New Braunfels Muni Airport     48  74  53  80 /   0   0   0   0
Burnet Muni Airport            47  72  54  79 /   0   0   0   0
Del Rio Intl Airport           57  76  60  88 /  10   0   0   0
Georgetown Muni Airport        45  70  52  79 /   0   0   0   0
Hondo Muni Airport             49  74  53  80 /   0   0   0   0
San Marcos Muni Airport        46  73  51  79 /   0   0   0   0
La Grange - Fayette Regional   47  72  52  78 /   0   0   0   0
San Antonio Intl Airport       50  73  55  79 /   0   0   0   0
Stinson Muni Airport           52  74  56  80 /   0   0   0   0

&&

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

$$

Short-Term...04
Long-Term...29
Aviation...04