539
FXUS64 KEWX 201721 AAA
AFDEWX

Area Forecast Discussion...UPDATED
National Weather Service Austin/San Antonio TX
1221 PM CDT Thu Jun 20 2024

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

.SHORT TERM...
(Today through Friday)
Issued at 340 AM CDT Thu Jun 20 2024

Key Messages:

*Moderate rainfall will continue this morning in the western half of
the area.

*The threat for widespread flooding has ended and the Flood Watch
has been cancelled.

*Scattered showers and thunderstorms are forecast today and with
tropical moisture still in place, could produce locally heavy rain.

Discussion:

Rain associated with Tropical Storm Alberto continues to move west
across South Central Texas early this morning. Due to westward track
of this storm, storm total precipitation has remained on the light
to moderate side given our proximity from the center circulation.
The eastern half of the area will see dry conditions through this
morning, while beneficial rainfall continues in the west through the
morning hours. With current rain rates remaining tame and the
general lull in the east, have opted to cancel the Flood Watch
early.

Rain chances do return across a majority of the area today in the
form of scattered showers and thunderstorms. Moderate CAPE but
little shear will keep any storms non-severe with locally heavy rain
the main threat given PWATS still on the order of 1.75-2.25 inches.
Widespread flooding or flash flooding is not anticipated with this
activity. Mostly cloudy skies will help keep temperatures below
average again today, generally ranging from the mid 80s to low 90s.
Any showers or thunderstorms will dissipate around sunset with
another mostly dry period in the forecast through Friday morning.
Remnants from Alberto will keep deep, tropical moisture in the area
with showers and thunderstorms possible again Friday. With little
upper level support, expect more isolated coverage of any storm
activity. Cloud cover will be more scattered this afternoon as well
which will bump afternoon highs up 2 or 3 degrees from those seen
today.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 340 AM CDT Thu Jun 20 2024

The center of the Subtropical Ridge shifts west over Texas to over
the southwestern states this weekend and remains there through the
middle of next week. A potential tropical system indicated in the
southwestern Gulf of Mexico should move west into Mexico early next
week. NHC currently (20/06Z) has a 50 percent chance of tropical
cyclone development. Its only impact on South Central Texas will be
a resurgence of tropical moisture on Sunday into Monday. An
unseasonably moist airmass with PWs of 1.4 to 2.2 inches remains
over South Central Texas through the period. While the Ridge will
provide some subsidence to inhibit convection, heating of the
increased PWs should be able to overcome this for low chances of
daytime showers and thunderstorms over our far southern areas on
most days, though up to the I-35 corridor Sunday and Monday. Locally
heavy downpours are possible Sunday and Monday due to the increased
PWs. Near to slightly above normal temperatures prevail through the
period. With the recently increased soil moisture and the increased
PWs, daytime mixing should be less efficient causing heat indices to
possibly reach advisory levels on Monday through Wednesday along and
east of the I-35 corridor.

&&

.AVIATION...
(18Z TAFS)
Issued at 1216 PM CDT Thu Jun 20 2024

The primary focus for the operational period will be the threat for
VCTS/TSRA through 03Z followed by the formation of MVFR CIGS and
perhaps some visby reductions at AUS after 08Z-09Z. Odds are favoring
widely scattered storms through the afternoon, so will opt to go
with prevailing FM group of TSRA at AUS, SAT, and SSF through the
evening hours. Winds will remain out of a 060-090 direction at 10-20
kts with a few gusts here and there. After MVFR CIGS tonight, we
should see a return to VFR CIGS by 16-18Z Friday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              75  92  74  95 /  30  20   0   0
Austin Bergstrom Intl Airport  73  91  72  93 /  30  20   0   0
New Braunfels Muni Airport     75  91  72  93 /  30  30   0   0
Burnet Muni Airport            73  89  73  92 /  20  10   0   0
Del Rio Intl Airport           77  93  77  95 /  60  40  20  10
Georgetown Muni Airport        72  91  72  92 /  20  10   0   0
Hondo Muni Airport             75  89  73  91 /  30  30   0  10
San Marcos Muni Airport        72  89  70  91 /  30  30   0   0
La Grange - Fayette Regional   74  89  72  91 /  20  30   0   0
San Antonio Intl Airport       75  90  74  92 /  30  30   0  10
Stinson Muni Airport           76  91  75  93 /  20  30   0  10

&&

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

$$

Short-Term...27
Long-Term...04
Aviation...MMM