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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1102 am CST sun Dec 21 2014

Aviation...
IFR/MVFR ceilings continue to encompass south central Texas. Kaus and
ksat have lifted into MVFR while kssf and kdrt continue with IFR
conditions. These two sites should improve within the next hour
or two. MVFR will continue for most of the remainder of the
afternoon and evening. Models seem to be too optimistic with
lifting the ceilings to 5kft and will keep higher MVFR prevailing.
Should see ceilings lower into low MVFR then possibly IFR once again
tomorrow morning. The wind component will become more
southwesterly tomorrow which should begin to scatter things out a
bit better.

Hampshire

&&

Previous discussion... /issued 950 am CST sun Dec 21 2014/

Update...
overcast skies continue across all of south central Texas.
Overrunning conditions will continue today as surface ridge axis
along the coastal plains slowly shifts east and return flow
develops at the surface and middle levels. This overrunning will allow for
some light patchy drizzle the next hour or so in a few spots but
not heavy enough to mention in the forecast at this time. Models
show the overrunning clouds will continue over the eastern half of
the County Warning Area all day while thinner moisture out west will mix out by
the afternoon giving way to some sunshine. Latest hrrr models
shows this as well. Made some minor adjustments to the grids but
overall current forecast trend is good.

Previous discussion... /issued 535 am CST sun Dec 21 2014/

Aviation.../12z taf cycle/
MVFR prevails across central taf sites with stratus ovc015 ceilings on
average with lower IFR ceilings at kdrt near 600ft as of 12z. Expect
kdrt to improve through late morning/after to VFR. Central sites will
be tricky with model guidance in disagreement on whether VFR
conditions will return feel stratus deck will erode in West Texas
and with weak S/SW flow will help more clearing towards ksat/kssf
than yesterday but it will be close. Feel kaus has least chance of
going VFR with high end MVFR through the afternoon. Expect central
sites to fall back to low MVFR to possibly IFR overnight. Have
followed more of NAM/rap consistency for kdrt with MVFR possibly
returning overnight as well. Much quicker clearing expected Monday
with VFR likely for all sites by noon.

Surface winds will be S/SW at 10 knots or less through the afternoon
and overnight. /Allen/

Previous discussion... /issued 357 am CST sun Dec 21 2014/

Short term (today through monday)...
patchy fog has developed in some spots and will maintain mention
through middle morning. An upper level trough developing over the
central states gets an enhancement from a couple short-waves
moving across Texas and a stronger short-wave currently moving
into the Pacific northwest. Weak isentropic lift maintains mostly
cloudy skies and near average temperatures today. A southwesterly
lower level flow develops on Monday as surface low strengthens in
the plains leading to well above average temperatures and warmest
of the next week as clouds erode.

Long term (monday night through saturday)...
the above mentioned Pacific northwest short-wave forces a strong
cold front south across south central Texas late Monday night into
early Tuesday. Then the upper level trough moves through later on
Tuesday. Some light rain showers are possible across eastern areas
with the front Tuesday morning. There may be a few sprinkles with
the upper level trough. However...have not mentioned as the lower
levels will be drying. A strong pressure gradient creates breezy
conditions with gusts up to 30 miles per hour Tuesday. Temperatures fall back
to below average for Tuesday into Wednesday. Some low lying spots
in The Hill Country and along the Escarpment will drop to freezing
Wednesday and Christmas mornings as winds decouple somewhat as
surface high moves across our area. The high moves off to the east
with southerly lower flow warming temperatures back to above
average for Christmas afternoon. Another strong cold front moves
across the area Friday leading to below average temperatures for
next weekend. No rain expected with this front due to limited
moisture. Beyond this forecast period...some models are showing
even colder air for next week in the days before the New Year.

&&

Preliminary point temps/pops...
Austin Camp Mabry 60 51 71 50 58 / - - - 10 10
Austin Bergstrom international Airport 60 48 71 49 59 / - - - 10 10
New Braunfels Muni Airport 61 50 73 51 60 / - - - 10 10
Burnet Muni Airport 58 47 72 46 55 / - - - 10 10
del Rio International Airport 64 45 75 49 60 / - - 0 - 10
Georgetown Muni Airport 59 49 71 48 56 / - - - 10 10
Hondo Muni Airport 62 48 74 47 61 / - - 0 - -
San Marcos Muni Airport 61 49 71 50 59 / - - - 10 10
La Grange - Fayette regional 62 51 73 54 58 / - 10 - 10 20
San Antonio International Airport 61 51 73 50 61 / - - 0 10 10
Stinson Muni Airport 62 50 74 50 61 / - - 0 10 10

&&

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

$$

Mesoscale/aviation...29
synoptic/grids...09
public service/data collection...33

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