Area forecast discussion
National Weather Service Austin/San Antonio Texas
313 am CDT Monday may 20 2013
Short term (today through tuesday)...
subsident westerlies aloft will keep Gulf moisture capped today. Low
clouds will begin lifting by late morning with diurnal heating becoming
partly to mostly sunny area-wide. Drier air over western sections
will result in temperatures well above normal with readings again
near the century mark. The continued Gulf moisture advection pattern
will moderate temperatures over The Hill Country as well as over
central and eastern sections where lower 90s will prevail. The
aforementioned upper level cap will keep convection from forming but
further north over west central Texas...lowered heights from slight
cooling aloft and a dry line focus over west central Texas may be
enough to spur development with the upper winds bringing potential
storms into The Hill Country by late afternoon. Late afternoon
prognostic soundings in The Hill Country show convective available potential energy above 3000 j/kg
with very little cap. Subsequently we will mention a low chance of
severe storms for late afternoon into early this evening over
portions of The Hill Country. The approaching upper trough over New
Mexico will enhance low level upslope flow over the Mexican mountains
tonight which may aid in development of late evening to early
morning thunderstorms. On Tuesday...the upper trough will shift east
across North Texas sliding a cold front into our northwest County Warning Area late
in the day. Very unstable air will be in place ahead of the front
(prog soundings indicated 4000 j/kg. Capes) so can certainly see
development of thunderstorms along the front and moving east across
The Hill Country by late in the day. Some of these storms could be
severe with the main threats being large hail and damaging winds.
&&
Long term (tuesday night through sunday)...
continued upper level disturbances and cooling aloft will continue
aiding thunderstorm development tomorrow night with some of the
storms becoming severe. Storms will exit to the east Wednesday
morning as disturbances push east. Upper ridging will begin
building over the area by late in the day. Highs Wednesday ranging
from near 90 over The Hill Country and eastern portions to the middle
to upper 90s over south central and western sections. As ridging
dries the air-mass...with lighter winds...slightly cooler Wednesday
night with lows in the upper 60s Hill Country...near 70 along the
I-35 corridor. The upper ridge will dominate much of the south
central United States Thursday through Saturday with continued
southeast winds and Gulf moisture for our region. Late night and
morning low clouds becoming partly cloudy afternoons will be the
pattern. Lows in the middle to upper 60s Hill Country...upper 60s to
near 70 I-35 corridor to low 70s elsewhere Thursday through
Saturday. Highs Thursday through Saturday will be in the upper 80s
to near 90 Hill Country...low 90s I-35 corridor and middle to upper
90s elsewhere. There may be a few sea breeze type showers which
may move north into our eastern sections with a slight increase in
southerly flow...but will now go with silent 10 percent probability of precipitation due
to uncertainty of enough coastal low level convergence. GFS model
wants to continue building the ridge over northern Mexico across
Texas next Sunday with a continued warm...dry weather pattern.
&&
Preliminary point temps/pops...
Austin Camp Mabry 93 72 93 72 92 / - - 20 40 -
Austin Bergstrom international Airport 92 71 91 71 91 / - - 20 40 -
New Braunfels Muni Airport 93 71 93 71 92 / - - 20 40 10
Burnet Muni Airport 91 69 90 68 90 / 20 20 20 40 -
del Rio International Airport 100 74 99 74 98 / - 20 10 20 -
Georgetown Muni Airport 90 70 89 70 89 / - 10 20 40 -
Hondo Muni Airport 97 72 96 71 95 / - 10 10 30 -
San Marcos Muni Airport 91 72 90 72 90 / - - 20 40 -
La Grange - Fayette regional 91 75 91 75 90 / - 10 20 30 20
San Antonio International Airport 93 73 93 72 92 / - - 20 40 10
Stinson Muni Airport 93 73 93 72 91 / - - 10 30 10
&&
Ewx watches/warnings/advisories...none.
&&
$$
Mesoscale/aviation...18
synoptic/grids...02
