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000
FXUS64 KEWX 101727
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1227 PM CDT Mon Aug 10 2020

.AVIATION...
Our stagnant weather pattern will continue for the next TAF period.
VFR conditions will prevail through the afternoon and evening at all
area airports. Winds will be out of the south at 10 to 15 kts with
gusts up to 25 kts this afternoon and early evening. MVFR ceilings
will develop overnight in Austin and San Antonio lasting until late
morning Tuesday. DRT will stay VFR through the entire period.

&&

.PREV DISCUSSION... /ISSUED 342 AM CDT Mon Aug 10 2020/

SHORT TERM (Today through Tuesday)...
The Subtropical Ridge remains centered generally over far western
Texas. Subsidence under the Ridge keeps rain out of most areas. The
seabreeze will not be as efficient on forcing due to weaker
convergence from a stronger surface pressure gradient. Also,
moisture levels (PWs) are forecast to be near or perhaps slightly
below seasonal levels. Regardless, similar to the last several days,
heating should be sufficient for a few showers and thunderstorms
during the afternoon into early evening hours. The model consensus
shows most activity over or near Lavaca county, however cannot rule
out an isolated shower closer to the I-35 corridor late afternoon or
early in the evening. All activity will dissipate by sunset with
loss of heating.

With the thermal ridge lingering across our area, persistence will
be followed on temperatures. Near seasonal humidity levels are
expected as dewpoints mix out each afternoon resulting in heat index
values only slightly warmer than actual temperatures. A few spots
closer to the Coastal Plains may not mix as efficiently with heat
index values flirting with advisory levels of 108 for an hour or
two. Fortunately, the stronger surface pressure gradient will bring
breezy and gusty winds during the afternoon into evening hours to
take the edge off the heat.

LONG TERM (Tuesday Night through Sunday)...
The subtropical ridge will continue to remain the dominant weather
feature through the forecast period. The center of the ridge will
initially reside over far west Texas/northern Mexico early this week,
and will then gradually strengthen while moving northward into the
desert southwest. For our region, we will continue to see above
normal temperatures across all areas. Our current thinking is the
heat will likely peak during the Wednesday through Friday time
frame with temperatures only easing slightly as we head into the
upcoming weekend. We could be flirting with Heat Advisory criteria
across the coastal plains along with a few spots east of the
I-35/I-37 corridors during the middle of this week and we will
continue to monitor.

There will be a low chance for some afternoon convection near the
coastal plains on Wednesday and Thursday. Some of this convection
could make it slightly farther north along the Highway 77 corridor
late this week, but overall rain chances will remain very low (~20%).
Just beyond the current forecast period, the models continue to
suggest a weakness in the upper ridge will develop over the western
Gulf of Mexico. This may allow for some isolated shower and
thunderstorm activity to develop farther inland, but rain chances
still do not look too favorable.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              78 101  77 103  77 /   0   0   0   0   0
Austin Bergstrom Intl Airport  77 100  76 100  76 /   0   0   0   0   0
New Braunfels Muni Airport     77 100  75 102  75 /   0  -    0  -    0
Burnet Muni Airport            76  98  75  99  75 /   0   0   0   0   0
Del Rio Intl Airport           78 103  79 104  79 /   0   0   0   0   0
Georgetown Muni Airport        78 100  77 101  76 /   0   0   0   0   0
Hondo Muni Airport             76 101  75 103  76 /   0   0   0   0   0
San Marcos Muni Airport        77 100  75 100  75 /  -   -    0   0   0
La Grange - Fayette Regional   78  99  77 100  77 /   0  -   -   -    0
San Antonio Intl Airport       78 100  77 101  77 /   0  -    0  -    0
Stinson Muni Airport           78 101  77 101  77 /   0  -    0  -    0

&&

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

$$

Short-Term/Aviation...05
Long-Term...YB
Decision Support...KCW