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Area forecast discussion
National Weather Service Austin/San Antonio Texas
334 PM CDT Thu Mar 23 2017

Short term (tonight through Friday night)...
strong wind gusts have extended east of the advy area into the I-35
corridor, and sustained winds are on the cusp of reaching advy
criteria. Mixing occurred early along I-35 as opposed to out west, so
perhaps winds are topping out about now. Will leave the advisory as
is and hand off the dilemma to the next shift. Winds are expected to
relax late tonight as the surface low over the High Plains to the
north tracks east. Models show good consistency in bringing a broken
line of mostly weak convection through the northern 2/3 of the
forecast area late tonight into Friday. A Low Cape/high shear
environment and a modest amount of moisture for Spring standards
should make this round of convection mostly garden variety, but areas
near and to the east of aus by midday Friday could be able to tap
into slightly deeper moisture and with a more robust afternoon
convection. The Storm Prediction Center outlook remains reasonable for a low end slight
risk day for the eastern counties, but mesoscale model runs such as
the Texas tech WRF suggest the deeper convection and severe threat
should be less than the areas of north-central & East Texas.

Post frontal drying will be efficient with downsloping westerly
winds, but the mid-level low pressure being well to the north may not
mix the gusty winds from aloft to the surface as much as they are
expected to the weather forecast office counties to the north. A Fire Weather Watch is
for now, just north of our counties, and this may need to be reviewed
in more detail as we begin to see the strength of the surface to 850
mb winds in upcoming model runs. The potential for a low-end rfw
event should be mainly northwest of a drt to t82(fredericksburg) line.


Long term (saturday through thursday)...

Good drying from friday's strong Central Plains storm could leave
Saturday morning with the coolest morning of the next week,
especially over the northwest counties. Coastal plains counties may fail to
lose all the shallow moisutre. Moisture return will resume Sunday but
not fast enough to bring a significant rain chance as a
shallow/smaller upper disturbance passes through the Central Plains
Sunday night. The progressive pattern aloft could keep the nocturnal
jet active, so some low-end convection (primary rw, isolated trw)
looks reasonable for some northern counties Sunday night. While the
frontal wind shift in the wake of the Sunday system is weak, winds
will not shift to southerly but rather to the east in the advance of
a much deeper trough/upper low that reaches Texas by Wednesday. This
system remains poorly agreed upon by deterministic solutions, with
the GFS running slowest/wettest and the CMC running fastest/driest.
Feel a ecm type middle ground solution will narrow the window in
future with a thunderstorm likely type period Wednesday into Wednesday night;
for now will keep with the blended population schemes until the
model trends show more consistency.


Preliminary point temps/pops...
Austin Camp Mabry 66 83 56 83 59 / 20 70 0 0 0
Austin Bergstrom Intl Airport 65 82 54 82 56 / 20 70 0 0 0
New Braunfels Muni Airport 65 84 54 83 57 / 20 60 0 0 0
Burnet Muni Airport 62 83 50 80 56 / 30 60 0 0 0
del Rio Intl Airport 61 86 53 86 59 / 20 - 0 0 0
Georgetown Muni Airport 65 81 52 81 56 / 20 70 - 0 0
Hondo Muni Airport 64 86 51 86 57 / 20 40 0 0 0
San Marcos Muni Airport 66 83 54 83 57 / 20 70 0 0 0
La Grange - Fayette regional 66 80 58 82 59 / 10 70 20 0 -
San Antonio Intl Airport 65 84 55 85 59 / 20 50 0 0 0
Stinson Muni Airport 65 85 55 86 59 / 10 50 0 0 0


Ewx watches/warnings/advisories...
Wind Advisory until midnight CDT tonight for the following
counties: Burnet...Edwards...Gillespie...Kerr...Kinney...Llano...
real...Val Verde...Williamson.


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