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afdewx

Area forecast discussion
National Weather Service Austin/San Antonio Texas
657 PM CDT sun may 28 2017

Aviation...
scattered to numerous rain showers/thunderstorms and rain continued across The Hill Country,
central Texas, and the Austin area. These will gradually push to the
east/southeast across the remainder of south central Texas as a surface trough
currently developing between San Antonio and del Rio shifts east. Have
gone with thunderstorms and rain at kaus to start the taf period, tempo at kdrt for
00z-02z, and ksat/kssf for 02z-06z. After that chances are uncertain
as surface trough focuses best chances southeast of I-35. VFR cigs
will prevail, except brief MVFR cigs/vsbys in shra/tsra. Some areas
of MVFR/IFR cigs may develop overnight into Monday morning. Cigs will
lift to VFR midday on Monday. Wind gusts up to 60 kts and gr/gs are
possible in the strongest tsra, otherwise winds will be 10 kts or
less.

&&

Previous discussion... /issued 320 PM CDT sun may 28 2017/

Update...
we've issued a Severe Thunderstorm Watch for the entire County Warning Area until 10
PM. Storms have developed along the front and will continue into the
evening. We have already issued a couple of severe thunderstorm
warnings and expect this to continue.

Previous discussion... /issued 250 PM CDT sun may 28 2017/

Short term (tonight through Monday night)...
upper air analysis this morning showed west-southwesterly flow over
Texas with a trough from central Canada to The Four Corners. At the
surface, a cold front was moving into our northwestern counties.
Winds ahead of the front were from the east to southeast and dewpoint
temperatures were in the lower to middle 70s. The upper level trough
will move across Texas during this period. With the upper flow nearly
parallel to the front, it will move slowly through the area tonight
and Monday. This will mean showers and thunderstorms will be likely
tonight and Monday. At the start of the period, model soundings show
cape around 4000 j/kg, but with 0-6 km wind shear only 20-30 kts.
This could produce strong to severe thunderstorms with large hail as
the mostly likely threat this evening. Atmosphere is fairly uniform
across the cwa, so where storms are worst will depend on how things
develop with small scale features that are not well resolved now.
Storms should weaken below severe strength by midnight. Expect
convection to continue overnight and during the day Monday. Monday
night chances will decrease with slight to low chance pops.

Long term (tuesday through sunday)...
the pattern will remain unsettled through the week with west-
southwesterly flow aloft. A series of short wave troughs will move
through the pattern bringing chances for convection. Wednesday night
and Thursday a stronger short wave will bring a better chance for
showers and thunderstorms and some higher rainfall totals. The
overall pattern will change little toward the end of the period and
low chances for convection will remain in the forecast until the end
of the forecast.

&&

Preliminary point temps/pops...
Austin Camp Mabry 70 82 67 85 68 / 70 50 30 40 30
Austin Bergstrom Intl Airport 69 81 66 85 67 / 70 50 30 40 30
New Braunfels Muni Airport 70 80 66 84 68 / 70 60 30 40 30
Burnet Muni Airport 67 80 65 83 66 / 60 40 20 30 30
del Rio Intl Airport 70 84 69 84 70 / 60 30 30 30 40
Georgetown Muni Airport 68 81 65 83 67 / 70 40 30 40 30
Hondo Muni Airport 69 83 68 86 68 / 70 40 30 40 30
San Marcos Muni Airport 70 80 66 85 68 / 70 60 30 40 30
La Grange - Fayette regional 71 81 68 85 69 / 70 70 30 40 30
San Antonio Intl Airport 70 82 68 85 70 / 70 50 30 40 30
Stinson Muni Airport 72 80 69 84 70 / 70 50 30 40 30

&&

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

$$

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