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Area forecast discussion
National Weather Service Austin/San Antonio Texas
602 am CST Thu Dec 8 2016

Aviation.../12z taf cycle/

MVFR conditions along with strong north winds of 20-30 knots are
ongoing this morning as of 12z. Expect MVFR conditions to
continue through the morning and early afternoon hours till near
22-23z when VFR should occur. Expect low-level turbulence with
the strong and gusty winds through this afternoon. Some gusts
could reach upwards of 35 knots at times this morning and early
afternoon. Winds will decrease through the late afternoon hours.
Aircraft flying within the 4000-8000 foot layer could experience
light icing as below freezing and near saturated conditions will
exist through the next 12 hours.

Winds will decrease through the late afternoon hours but remain
out of the north at 10-15 knots before reducing further to 10
knots or less overnight into Friday morning. A widespread freeze
is expected at all terminals Friday morning with VFR conditions
occurring.

&&

Previous discussion... /issued 414 am CST Thu Dec 8 2016/

Short term (today through friday)...
the long awaited cold front is pushing south through central Texas
this morning with plenty of gusto. Gusty winds already this
morning behind the front to 30 mph have been observed so it looks
like the Wind Advisory will be right on track. The colder drier
air should arrive in the Austin area right around 12z likely
meaning the high temperature has already been reached this
morning for northern areas. Throughout the morning and into the
afternoon, a tight pressure gradient behind the front will keep
winds in the 20-30 mph sustained range with gusts potentially as
high as 40 mph. The gradient relaxes around mid afternoon bringing
winds below the 26 mph threshold for the Wind Advisory, hence the
expiration time of 22z.

On radar, an area of very light returns was currently located
north of the County Warning Area. The suite of hi-res models keep this area of
light precip well to the north of the County Warning Area and deteriorate this
substantially through the morning hours. As such, have lowered any
mentionable pops beyond 18z today.

As winds decrease overnight, temperatures should continue to
decrease and fall into the 20s for the plateau, Hill Country and
northern half of the County Warning Area. While lingering cloud cover could
prevent some areas in the far southern zones from realizing
freezing temps, most areas will likely see at least 32 degrees by
Friday morning. Planning on a freeze warning for much of the
remaining counties in the County Warning Area but held off on this shift due to
potential npw product complications. Will handle with an Special Weather Statement for
now.

Long term (friday night through wednesday)...
surface winds swing back to the southeast as the surface ridge
moves northeast Saturday allowing low level moisture advection to
begin and set up another overrunning pattern for late Saturday
night and Sunday. While models are depicting some quantitative precipitation forecast generation
across the eastern half of the County Warning Area due to a strong llj, believe
that due to the shallow moisture profile, only light rain or
drizzle will be the most likely scenario early Sunday.

Considerable model discrepancy exists towards mid week with the
handling of a cold front passage. At this time, the GFS is
significantly more bullish with the evolution and magnitude of the
front advertised whereas European model (ecmwf)/Canadian do not depict nearly as
significant a front. Seeking clarity in ensembles of both the ecm
and men have proved to be futile with 10-20 degree low temperature
separation in the hi/low members. Thus have gone with a consensus
blend for this time period until more clarity can be afforded in
later model runs.

&&

Preliminary point temps/pops...
Austin Camp Mabry 42 29 46 36 50 / 10 - 0 0 20
Austin Bergstrom Intl Airport 44 28 46 34 52 / 10 - 0 0 20
New Braunfels Muni Airport 44 30 47 35 51 / 10 - 0 0 20
Burnet Muni Airport 39 26 44 33 50 / 20 - 0 0 20
del Rio Intl Airport 45 31 46 34 54 / 20 0 0 0 0
Georgetown Muni Airport 40 27 44 34 50 / 20 - 0 0 20
Hondo Muni Airport 47 30 48 36 50 / 10 - 0 0 10
San Marcos Muni Airport 44 29 46 35 51 / 10 - 0 0 20
La Grange - Fayette regional 46 30 47 37 55 / 10 - 0 0 20
San Antonio Intl Airport 45 32 47 37 51 / 10 - 0 0 10
Stinson Muni Airport 47 32 48 37 51 / 10 - 0 0 10

&&

Ewx watches/warnings/advisories...
Wind Advisory until 4 PM CST this afternoon for the following
counties: Bastrop...Bexar...Caldwell...Comal...Gonzales...
Guadalupe...Hays...Lee...Medina...Travis...Williamson...Wilson.

&&

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