368
FXUS64 KEWX 212327
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
627 PM CDT Sat Sep 21 2024

...New AVIATION...

.SHORT TERM...
(Tonight through Sunday night)
Issued at 108 PM CDT Sat Sep 21 2024

Daytime mixing will continue to scatter out low clouds and produce
partly cloudy, and then mostly clear, skies late this afternoon into
early evening. The general pattern of low-level clouds returning by
late evening and persisting overnight into the next morning will
continue, but lower boundary layer humidity should result in less
fog along and east of I-35/I-37 Sunday morning.

The approach of a longwave trough and near-surface cold front will
bring sufficient lift for showers and a few thunderstorms across the
northern Rio Grande Plains, Edwards Plateau, and western Hill
Country Sunday evening into the overnight hours. Rainfall will be
spotty and average 1/10 inch or less. Daytime temperatures will be 2-
4F cooler across the entire area on Sunday because of additional
cloudcover.

&&

.LONG TERM...
(Monday through Saturday)
Issued at 108 PM CDT Sat Sep 21 2024

A much-needed pattern change appears to be on the way for the
last full week of September. A mid-level trough will gradually erode
the 500mb high that`s been keeping things hot and dry for the last
couple of weeks in South Central Texas. On Monday, a cold front will
start sliding southward into the Hill Country and Southern Edwards
Plateau. Model trends continue to bring this front to a halt over the
Hill Country late Monday and it is unlikely to make much progress
until late Tuesday per the latest Canadian/ECMWF runs. The GFS is not
as aggressive with forcing the boundary south, but the trend is your
friend, and this time of year usually calls for frontal boundaries
sliding further south the global model guidance usually suggests. In
any matter, cooler temperatures, ample cloud cover, and an
overrunning regime should result in scattered showers and the
occasional isolated thunderstorm Monday afternoon, Tuesday
afternoon, and again Wednesday afternoon and evening.

By Thursday, the mid-level trough should start to finally shift
eastward into the Ohio Valley, resulting in a drying trend for the
region. Dewpoints will be much more manageable, as slightly cooler,
more so drier air, will work its way south with the frontal boundary.
Expect more seasonable high and low temperatures in the 80s
Wednesday, with mid to upper 80s and perhaps some lower 90s
Thursday-Saturday.

&&

.AVIATION...
(00Z TAFS)
Issued at 620 PM CDT Sat Sep 21 2024

VFR flight conditions persists into tonight with few to sct mid-
level cumulus before low clouds develop and increase overnight into
Sunday morning with mainly MVFR ceilings. The MVFR ceilings should
improve to VFR levels at the TAF sites by Sunday afternoon. Winds
remain out of the south-southeast to east-southeast of light to
moderate speeds. Speeds will be greatest to around 12 to 13 knots
with occasionally higher gusts from the late afternoon through the
evening hours.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              75  96  74  93 /   0   0  10  10
Austin Bergstrom Intl Airport  73  95  73  93 /   0   0   0  10
New Braunfels Muni Airport     74  96  73  95 /   0   0   0  10
Burnet Muni Airport            73  92  71  87 /   0   0  20  20
Del Rio Intl Airport           79  95  76  91 /  10   0  30  40
Georgetown Muni Airport        73  94  73  90 /   0   0  10  10
Hondo Muni Airport             74  94  72  93 /   0   0  10  10
San Marcos Muni Airport        73  94  71  93 /   0   0   0  10
La Grange - Fayette Regional   73  94  72  93 /   0   0   0  10
San Antonio Intl Airport       76  94  75  93 /   0   0  10  10
Stinson Muni Airport           76  95  74  96 /   0   0   0  10

&&

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

$$

Short-Term...Zeitler
Long-Term...MMM
Aviation...Brady