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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1239 PM CDT Tuesday Jul 26 2016

Aviation...
for this taf period the main concern will continue to the
scattered to widespread showers and thunderstorms. Activity has
already begun to develop, mainly along and south of Interstate 10.
Showers and storms will drift westward through the afternoon and
into the evening hours. Thunderstorms in the vicinity has been included at all terminals
through the afternoon to cover the isolated nature of the storms,
with the best chance being at Sat/ssf. Because of these the San
Antonio terminals include a tempo group for thunderstorms from 18z
to 22z. As confidence increases tafs for the terminals will be
amended if storms approach.

Shower and thunderstorm activity will diminish through the
evening hours with a dry forecast overnight. Another round of high
end MVFR stratus cigs is possible across the I-35 corridor, so a window
of MVFR cigs is reflected in aus/Sat/ssf.

Tomorrow afternoon will see a return to VFR during the afternoon with
another chance of isolated showers and thunderstorms. Given the
uncertainty of the location and coverage of these storms have not
mentioned them in this taf package, but they will be reflected in
later tafs.

&&

Previous discussion... /issued 655 am CDT Tuesday Jul 26 2016/

Aviation...
although patchy fog has not developed at any of the I-35 taf sites
despite developing at some nearby sites, MVFR ceilings have
developed at ssf and aus. All I-35 taf sites should develop MVFR
ceilings by 14-15z that should last until around 17z. Winds should
generally remain easterly around 5-10 knots this morning.

The main aviation concern for this afternoon will scattered to
widespread showers and thunderstorms that develop generally after
17z for the I-35 taf sites and 19z for drt. Rain chances are
greatest at Sat/ssf which is in closer proximity to outflow
boundaries left behind by yesterday's convection and the ongoing
complex of storms along the southeast Texas Gulf Coast associated
with the broad inverted trough. There is more uncertainty at aus
which may be too far north of the remnant boundaries and drt where
coverage will be more isolated or scattered. Tafs are written to
reflect this and will be amended as confidence increases.

Previous discussion... /issued 346 am CDT Tuesday Jul 26 2016/

Short term (today through wednesday)...
yesterday evening's complex of storms that moved through the I-35
corridor continues to decay early this morning as it moves toward
the Rio Grande. Additional showers are re-developing early this
morning across the northern coastal Bend and Upper Texas coast
closer to a low level moisture convergent axis. The broad mid and
upper level low centered across the northwest Gulf of Mexico will
elongate westward today, with another spoke of energy wrapping
into portions of south Texas. A healthy 2.1-2.3 inches of
precipitable water is pooled today across the southern half of
the County Warning Area.

Through the next few hours showers should be focused across the
coastal plains and southeast Texas, closer to the aforementioned
convergent axis. As de-stabilization takes place midday through
the afternoon coverage of showers and storms should increase
northwest into the I-35 corridor and Hill Country. Best chances
today for rainfall will be generally along and south of a
Kerrville to New Braunfels to Hallettsville line. Storms late
afternoon and evening should focus across the southwest County Warning Area as
indicated by several hi res models, before gradually dissipating
after sunset.

A few storms yesterday developed some stronger downdrafts and
wind gusts up to 50 mph. Forecasted dcape values this afternoon
are not quite as high as yesterday, nevertheless a few stronger
wind gusts are possible. A few pockets of 2-3 inches of rainfall
are possible today given the moisture profile, with averages of
1/2 to 1 inch.

Tonight and Wednesday the low opens with the main energy pivoting
into the lower Mississippi River valley. A broad weakness is left
behind over south-central and with precipitable water values
decreased slightly, but still above 2 inches in some areas.
Expected another round of afternoon showers and storms on
Wednesday. Coverage should be slightly less than today.

Long term (wednesday night through monday)...
drying occurs Thursday and Friday with low chances for showers
mainly focused with what is left of the moisture pool and weakness
aloft across the eastern County Warning Area. Over the weekend the ridge nudges
back into the area. Temperatures warm and look to creep back up
above normal over the weekend and into early next week.

&&

Preliminary point temps/pops...
Austin Camp Mabry 95 76 96 76 96 / 40 20 40 20 30
Austin Bergstrom Intl Airport 94 75 94 76 96 / 50 20 40 20 30
New Braunfels Muni Airport 93 75 95 75 96 / 60 30 40 20 20
Burnet Muni Airport 93 74 93 75 95 / 30 20 40 20 30
del Rio Intl Airport 97 77 96 78 98 / 50 30 30 20 10
Georgetown Muni Airport 93 75 94 76 95 / 30 20 40 20 30
Hondo Muni Airport 94 76 94 75 96 / 60 40 40 20 20
San Marcos Muni Airport 92 75 94 75 96 / 60 30 40 20 30
La Grange - Fayette regional 92 76 94 77 96 / 50 20 40 20 30
San Antonio Intl Airport 93 76 94 77 96 / 60 30 40 20 20
Stinson Muni Airport 94 77 96 77 98 / 60 30 40 20 20

&&

Ewx watches/warnings/advisories...
none.
&&

$$

Mesoscale/aviation...Treadway
synoptic/grids...24
public service/data collection...30

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