Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Austin/San Antonio Texas
232 PM CST Tuesday Dec 1 2015
Short term (tonight through Wednesday night)...
Quiet sensible weather over the next week as a dry front moves
through the region overnight into Wednesday morning with ample
sunshine expected Wednesday.
High clouds are streaming over the region from the southwest ahead
of a longwave trough axis over the four corner region per latest
water vapor and rap analysis. Surface observations this afternoon
place a weak cold front/dryline over the Panhandle of Texas
characterized with low teens dewpoints to the west of the boundary
and 30s/40s dewpoints to the east. This boundary will shift
through the entire region Wednesday morning to early afternoon and
bring some stronger north winds of 10-15 miles per hour. Drier air aloft has
been able to precede the front and this has acted to increase the
condensation pressure deficits with weaker isentropic upglide for
the coastal plains. While some virga will be likely overnight
ahead of the front...the lower levels per NAM/GFS soundings
suggest it will quite difficult for precipitation to reach the
ground. Have removed and weather mention for the overnight period
and reduced rain chances to only 10% for the coastal plains with
even less values farther west.
The clearing overnight and the drier air moving in will allow for
a cooler morning and have gone below superblend values that are
more in line with ensemble means which line up towards raw mav/met
MOS. Expect a decent warm-up Wednesday afternoon as ample sun combines
with the dry air in place. Highs should reach into the low to
Long term (thursday through tuesday)...
Continued quiet weather conditions are expected through at least
Saturday as clear skies and slightly below normal temperatures
occur. By Sunday into next week...another cold front is expected
but may also be on the dry side with only limited rain chances.
Thursday and Friday morning will be coolest of the period with
localized freezing pockets occurring in The Hill Country. Other
areas are expected to drop into the middle to upper 30s as clear
skies and high pressure allowing for near calm winds aids a good
radiational cooling set-up. Highs each day will warm back into the
low to middle 60s.
By late week into the weekend...a stronger shortwave trough will
shift across the central and Southern Plains that will help push
another cold front through the region by late Sunday into Monday.
Precipitable waters only recover to 0.5"-0.7" ahead of the front and it will be
quite difficult to get enough moisture squeezed out of the
atmosphere for rain chances. Have reduced rain chances Sunday to
the 10-15% range given the good model concensus of little to no
rain expected. There will be another likely chance of some
freezing temperatures in The Hill Country next Tuesday morning.
Preliminary point temps/pops...
Austin Camp Mabry 44 65 41 61 39 / - - 0 0 0
Austin Bergstrom international Airport 40 65 37 61 35 / - - 0 0 0
New Braunfels Muni Airport 44 65 38 62 37 / - - 0 0 0
Burnet Muni Airport 40 62 37 60 37 / - 0 0 0 0
del Rio International Airport 45 68 39 65 39 / - 0 0 0 0
Georgetown Muni Airport 40 62 37 59 36 / - - 0 0 0
Hondo Muni Airport 43 67 36 64 36 / - - 0 0 0
San Marcos Muni Airport 43 64 38 61 37 / - - 0 0 0
La Grange - Fayette regional 46 64 40 61 38 / 10 - 0 0 0
San Antonio International Airport 46 67 38 64 38 / - - 0 0 0
Stinson Muni Airport 46 66 40 64 39 / - - 0 0 0
public service/data collection...Treadway