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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1137 PM CDT Tuesday Sep 30 2014

Aviation...
area VAD wind profilers so a slow strengthening to the low-level
winds just off the surface this evening. 2kft winds should peak
out around 20 knots near daybreak from the south and this should
allow for the formation of morning stratus. High-res model
guidance is picking up on this with an arrival time at the San
Antonio sites between 9 and 10z and into Austin about an hour
later. The depth of the moist layer will be rather shallow
according to forecast soundings. Will go with 1kft ceilings for
now for the I-35 taf sites but there is the possibility of IFR
conditions. With the depth of the cloud layer being small...all
stratus should dissipate/lift by 16 to 17z. Another round of
stratus is expected tomorrow night. Low level jet should be even stronger
which could keep clouds around a bit longer...but this is just
outside the current taf period.

Hampshire

&&

Previous discussion... /issued 918 PM CDT Tuesday Sep 30 2014/

Update...
just sent an update to re-trend forecast variables through 12z
Wednesday...but no major changes to the earlier forecast. We are
still expecting some patchy fog on the coastal plains east of the
I-35 corridor.

Previous discussion... /issued 334 PM CDT Tuesday Sep 30 2014/

Short term (tonight through Tuesday night)...
latest visible images and surface observations show a surface low
pressure system over the Brownsville area. Crp radar shows light
to moderate echoes along the coast as a weak sea-breeze convergence
zone takes place and slowly pushes to the north. Kept for the
remainder of this afternoon period a slight chance for isolated
showers/thunderstorms over the far southeast. Partly cloudy skies will
prevail this evening but becoming cloudy overnight across most of
the area as southerly flow returns and low level moisture increases.
After a cloudy morning on Tuesday and even some patchy fog across
the coastal plains...skies will become mostly sunny with highs in
the upper 80s across The Hill Country to lower 90s along
Interstate 35 and southern Rio Grande plains.

Long term (wednesday through monday)...
a zonal flow will dominate the area through early Thursday before
an upper level trough swings across central Texas between Thursday
evening and early Friday. A cold front will push across The Hill
Country Thursday evening and along Interstate 35 around midnight
Friday. It will continue to push southeast overnight and exit the
coastal plains by Friday morning. This system will bring rain
chances across south central Texas mainly over areas east of
Highway 281. With deeper moisture available across the coastal
plains...expect moderate rainfall amounts mainly east of a
Giddings to Seguin to Karnes City line. Storm total rainfall
amounts will generally be around one quarter to one half inch with
very isolated spots of one to two inches. Areas along and west of
Highway 281 will generally get few a hundredths of an inch or
less.

Weather conditions will rapidly improve in the wake of the cold
front with a drier and cooler airmass spreading across the region
on Friday and Saturday. Slightly below average temperatures are
expected on Friday and into the upcoming weekend with highs in the
low to middle 80s and overnight lows in the low to middle 50s across The
Hill Country.

&&

Preliminary point temps/pops...
Austin Camp Mabry 72 93 75 92 66 / - - - 20 40
Austin Bergstrom international Airport 69 92 72 92 64 / - - - 20 40
New Braunfels Muni Airport 70 94 73 94 66 / - - - 20 40
Burnet Muni Airport 69 91 73 91 62 / - - - 20 30
del Rio International Airport 71 92 74 92 66 / 0 - - 10 10
Georgetown Muni Airport 71 92 74 91 62 / - - - 20 30
Hondo Muni Airport 70 94 73 94 65 / 0 - - 10 30
San Marcos Muni Airport 70 92 73 92 65 / - - - 20 40
La Grange - Fayette regional 73 92 75 92 69 / 10 10 10 20 50
San Antonio International Airport 73 93 76 94 67 / - - - 20 30
Stinson Muni Airport 72 94 75 94 67 / - - - 20 30

&&

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

$$

Mesoscale/aviation...29
synoptic/grids...26

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