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Area forecast discussion...updated 
National Weather Service Austin/San Antonio Texas
1213 PM CST Monday Nov 30 2015

/18z tafs/
MVFR conditions will prevail across the area terminals through
late this afternoon. VFR conditions return this evening continuing
through Tuesday along the I-35 corridor. Kdrt could see MVFR ceilings
from 13z through 18z Tuesday. A weak cold front is forecast to
push across The Hill Country by midnight/early Tuesday...along
I-35 around 07z. Northeasterly winds will prevail across the I-35
sites while southeasterly winds dominate across the Rio Grande and


Previous discussion... /issued 518 am CST Monday Nov 30 2015/

Aviation discussion...for 12z taf period...
continued poor flying conditions persist through the morning hours
but improvement is expected finally today. Through the morning
hours...IFR/LIFR ceilings and MVFR visible are expected at the i35
corridor terminals. Current observation at surrounding sites indicate this
will occur within the first hour or two of the period. By late
morning...the trend of improvement will begin as MVFR ceilings will
prevail through the afternoon hours. An approaching front should
begin clearing skies from the northwest by this evening and
improvement to VFR is expected by or just after nightfall tonight.

Previous discussion... /issued 411 am CST Monday Nov 30 2015/

Short term (today through tuesday)...
upper level low currently over the northern/central rockies moves
out into the plains this afternoon with a moderate upper level
jet streaming across Texas. The cold front that moved through on
Friday has pushed a bit further out into the northwestern Gulf of
Mexico. A fairly moist lower level airmass lingers across south
central Texas early this morning. Weak isentropic lift allows for
patchy drizzle...along with isolated light rain showers across
eastern areas this morning. The lift ends this afternoon ushering
in a slightly drier airmass ending the precipitation. Patchy fog
can also be expected this morning. Tonight into Tuesday...upper
level low moves into the Midwest with a developing trough dropping
southeast into the southern rockies. Isentropic lift develops as
the front pushes back closer to the coast as a warm front to
generate light rain showers near the coastal plains overnight.
Lift strengthens on Tuesday with the rain showers pushing west of
I-35 to along the Escarpment and southern parts of the Rio Grande
plains by late in the day. Some clearing allows for warmer
afternoons. However...well below normal temperatures continue.

Long term (tuesday night through sunday)...
as the upper level low moves from the Midwest to across the Great
Lakes it forces a cold front as well as The Rockies upper level
trough across Texas late Tuesday night and Wednesday. Dynamic and
isentropic lift peak Tuesday night allowing for isolated to
scattered showers over all areas...except for the Rio Grande into
the Edwards Plateau where a drier airmass will remain. Weak
instability and only near seasonal precipitable waters keep thunderstorms out of
the forecast. Surface high pressure behind the front brings a
drier airmass to all areas on Wednesday with rain showers ending
from north to south in the morning to midday. Rainfall totals from
late tonight through Wednesday will generally be less than one
quarter inch. Ridging at the surface and aloft takes hold Thursday
into Friday for fair weather. Lower dewpoints and light winds
allow for freezing temperatures in parts of The Hill Country
Thursday and Friday mornings. Another upper level trough moves to
the east across the Southern Plains Sunday into Monday. Southerly
flow returns on Saturday bringing increasing moisture leading to
slight chances of showers for Sunday into Sunday night. This
trough is deeper and may create better instability due to colder
temperatures aloft to allow for thunderstorms. For now...however
will leave mention out of forecast to await more consistency
and consensus in the models. Generally below normal temperatures
are expected.


Preliminary point temps/pops...
Austin Camp Mabry 56 46 56 46 58 / 10 10 20 20 10
Austin Bergstrom international Airport 55 46 56 45 59 / 10 10 20 30 10
New Braunfels Muni Airport 56 48 57 47 59 / 10 20 20 30 20
Burnet Muni Airport 56 41 57 42 56 / 10 - 10 20 10
del Rio International Airport 61 49 62 48 62 / - - 10 10 10
Georgetown Muni Airport 56 43 56 41 56 / 10 10 20 20 10
Hondo Muni Airport 61 49 59 47 61 / 10 10 20 20 10
San Marcos Muni Airport 56 47 57 46 59 / 10 10 20 30 10
La Grange - Fayette regional 55 49 57 48 59 / 20 20 30 40 20
San Antonio International Airport 59 50 58 48 60 / 10 10 20 30 10
Stinson Muni Airport 58 51 58 49 61 / 10 20 20 30 20


Ewx watches/warnings/advisories...


public service/data collection...Treadway

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