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Area forecast discussion
National Weather Service Austin/San Antonio Texas
257 PM CST sun Feb 19 2017

Short term (tonight through Monday night)...
latest water vapor images show a long-wave upper level trough
axis extending from the intermountain west southeast into The
Four Corners region. This feature is forecast to split this
evening...sending the southern portion of the main trough/short-wave
across northeast Mexico and into our area overnight. At the surface,
a dry-line located across the extreme northwest Val Verde County as
of this writing, is expected to push further west. With that in main
and expected convection along and east of I-35 later tonight, Storm Prediction Center day
1 convective outlook has been updated and now covers most area with
slight risk of severe thunderstorms.

Dfx radar is already picking up light to moderate rain-showers along
the Rio Grande and Edwards Plateau areas. This trend is expected to
increase as the upper level short-wave moves to the east this
evening. A hand-full of hires models agree on scattered showers and
thunderstorms to develop across the Rio Grande later this afternoon
with widespread convection forming early this evening into the
overnight hours. By early this evening, increased instability and
with capping inversion eroding, expect storms to rapidly become
strong to severe. As the night progresses, the severe weather risk
diminishes and transition into a heavy rain event with isolated
strong storms mainly along and east of I-35.

Overall situation from early this evening into the overnight hours
is as follow: strong to severe thunderstorms are possible across most
areas across south central Texas (exception extreme northwest and e).
Primary threats will be wind gusts up to 60 mph and large hail up to
one inch in diameter. Also, heavy rain is expected as the storms move
along and east of Highway 281 due to the fact of well above
precipitable water values (1.4 to 1.7 inches). That said, storm total
rainfall amounts of 1 to 2 inches are possible with isolated pockets
of 4 to 5 inches mainly along and east of I-35.

The dry-line moves back to the east Monday morning with clearing
expected to begin out west and then into the I-35 corridor by noon
Monday. Since the upper level trough/cutoff low could be right on top
of US during the afternoon hours, decided to keep slight chances
for showers and storms mainly east of Highway 183.



&&

Long term (tuesday through sunday)...
the upper level system will continue to push to the southeast and
into the Gulf waters while ridging builds over the area Tuesday and
Wednesday of next week for dry and pleasant weather. Dry conditions
persist into next weekend. A cold front is expected to push across
the area late Sunday into Monday and brings our next chances for rain
across the area. Temperatures will be above normal values through the
extended period even with the passage of dry front on Friday and the
wet one late Sunday into Monday of next week.

&&

Preliminary point temps/pops...
Austin Camp Mabry 62 73 53 79 52 / 100 40 - - 0
Austin Bergstrom Intl Airport 61 71 52 78 50 / 100 50 - - 0
New Braunfels Muni Airport 61 72 53 79 51 / 100 40 - - 0
Burnet Muni Airport 58 71 49 76 48 / 100 20 - - 0
del Rio Intl Airport 55 77 50 82 48 / 50 10 0 0 0
Georgetown Muni Airport 61 71 51 77 49 / 100 40 - - 0
Hondo Muni Airport 59 74 49 81 48 / 70 20 - 0 0
San Marcos Muni Airport 62 71 53 79 51 / 100 50 - - 0
La Grange - Fayette regional 64 72 55 77 53 / 100 60 10 10 -
San Antonio Intl Airport 61 73 53 79 52 / 100 30 - - 0
Stinson Muni Airport 62 73 54 79 52 / 100 30 - - 0

&&

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

$$

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