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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
917 am CST Monday Dec 22 2014

Update...
with some locations on the plateau still reporting foggy
conditions at 15z. Extended patchy fog mention for these locations
another few hours. Also ran Standard update for hourly T trends
and dew T. Otherwise...forecast on track.

&&

Previous discussion... /issued 600 am CST Monday Dec 22 2014/

Aviation...
strong southeasterly flow above the surface has resulted in
IFR/LIFR ceilings this morning. Also seeing visible reduced in fog with
the worst visible at drt. Conditions should improve by around noon as
west winds move in. A cold front will move through the region
Tuesday bringing north winds by mid-morning.

Previous discussion... /issued 408 am CST Monday Dec 22 2014/

Short term (today through tuesday)...
fog covers most of south central Texas early this morning. A
deepening trough moving out into the plains will cause southwest
to westerly lower level winds. Low clouds and fog erode from west
to east by middle morning allowing temperatures to rise to well above
average this afternoon. A pre-frontal trough moves across our area
tonight...then a cold front early Tuesday with an upper level
trough late Tuesday. The front and upper trough generate upward
motion of sufficient moisture to produce slight chance to chance
probability of precipitation for showers northeast of a Rocksprings to New Braunfels to
Karnes City line. Rainfall will be light with amounts less than
one quarter inch. Cold advection and cloud cover will drop
temperatures to below average on Tuesday. Breezy conditions will
develop in the wake of the frontal passage due to tight pressure
gradient.

Long term (tuesday night through sunday)...
the breezy conditions continue into Tuesday night keeping the
temperatures from bottoming out...only flirting with the freezing
mark in some low lying and wind sheltered Hill Country spots
Wednesday morning. Below average temperatures continue Christmas
evening through Christmas morning. More widespread freezing
temperatures are expected Christmas morning as the surface high
settles over the area...but still mainly in low lying spots in
The Hill Country and along the Escarpment. The surface high moves
off to the east allowing a southerly flow and temperatures warming
to above average for Christmas afternoon. A zonal flow aloft
prevails Friday through Sunday with the models delaying the next
strong cold front until Friday night into early Saturday. Have
warmed Friday afternoon temperatures only slightly. Some models
are showing rain chances. However...moisture will be limited and
have not included probability of precipitation. Below average temperatures are expected
Saturday and Sunday which will likely continue beyond this
forecast through the New Year.

&&

Preliminary point temps/pops...
Austin Camp Mabry 73 49 56 38 56 / 0 10 30 - 0
Austin Bergstrom international Airport 72 47 57 37 56 / 0 10 20 - 0
New Braunfels Muni Airport 74 49 58 38 57 / 0 10 10 - 0
Burnet Muni Airport 71 46 54 36 53 / - 10 30 0 0
del Rio International Airport 75 48 59 37 59 / 0 - - 0 0
Georgetown Muni Airport 70 47 55 36 54 / 0 10 30 - 0
Hondo Muni Airport 75 46 61 35 59 / 0 - 10 0 0
San Marcos Muni Airport 72 48 57 36 56 / 0 10 20 - 0
La Grange - Fayette regional 73 52 57 38 56 / - 10 30 - 0
San Antonio International Airport 75 50 59 38 58 / 0 - 10 - 0
Stinson Muni Airport 75 50 59 38 59 / 0 - 10 - 0

&&

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

$$

Mesoscale/aviation...09
synoptic/grids...03
public service/data collection...33

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