FXUS64 KEWX 190434

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1034 PM CST Sat Jan 18 2020

Cold front that passed over the region this morning and afternoon
has cleared the coast. All sites are VFR and will prevail through the
period. North winds will slowly begin to weaken as surface pressure
gradient relaxes behind the front overnight. Expecting gusts to come
down overnight. As the surface high translates across the state
Sunday, winds turn to a more northeasterly direction tomorrow
afternoon. Return flow begins just beyond the 30 hour TAF period.


PREV DISCUSSION... /ISSUED 231 PM CST Sat Jan 18 2020/

SHORT TERM (Tonight through Sunday Night)...
The cold front has just about cleared the far southern CWA and will
continue south through the remainder of the afternoon. Residual
showers across the southeastern counties of the CWA will gradually
come to an end, with clearing across the remainder of the southern
and eastern CWA also taking place through the afternoon and evening.
Gusty north winds at times will continue through the afternoon.
While wind speeds will weaken slightly tonight, they won't
completely de-couple. Therefore despite a clear and colder night,
mixing should prevent temperatures from reaching freezing, with the
exception of the northern Hill Country. Elsewhere lows in the mid
30s to low 40s are forecast. Mostly sunny but cool conditions on
Sunday. Highs in the mid 50s to around 60 are forecast.

Winds are forecast to de-couple Sunday night and combined with the
dry airmass in place should result in colder temperatures than
tonight. We are currently forecasting low temperatures Monday morning
in the upper 20s to low 30s in some drainage areas of the Hill
COuntry and east of I-35/north of I-10 with mid to upper 30s
elsewhere. The one thing to watch that could influence the
temperature forecast warmer may be a quicker arriving and thicker
mid level deck of clouds that is indicated to possibly develop
across the western half of the CWA.

LONG TERM (Monday through Saturday)...
The upper high behind this weekend's cold front will shift east
across Texas during the day on Monday which will cause surface winds
to become more easterly. With the cool airmass in place temperatures
both Monday and Tuesday will continue to run a good 5 to 7 degrees
below normal, finally feeling like winter after several warm days.

A large upper trough with embedded shortwaves will approach late
Tuesday and interact with the increasing moisture across South
Central Texas due to the southerly return flow and produce showers
across the Rio Grande Plains into the Edwards Plateau. With the large
trough across the Central Plains the shortwaves in the larger scale
pattern will move across Texas Tuesday night through Wednesday night.
This appears to be the window for the best rain chances across the
area. The shortwaves exit during the day on Thursday concentrating
rain chances across eastern areas of South Central Texas. The large
scale trough finally drops into the Central Plains late Thursday into
Friday which will drag a cold front through the area Friday morning
clearing out precipitation. Temperatures that had warmed into the
upper 60s on Thursday due to the increased moisture will moderate
behind the front Friday and Saturday to near normal (in the low 60s).
All-in-all models have around an inch of rain for most of the area
for the middle to late part of next week. The GFS continues to be the
most progressive of the models and is weakest with the trough
producing the lowest QPF of the 3 main global models. The ECMWF and
Canadian are both much wetter, deeper, and stronger with as much as
2 inches along and east of Interstate 35 before the rain ends on
Friday. With the trough still in the days 4-6 time frame we will see
if models come to a consensus over the next 24-36 hours.
Precipitation through the period will be mostly showers, but a few
isolated thunderstorms will be possible, especially in the Wednesday
to Thursday time frame.


Austin Camp Mabry 38 57 35 56 38 / 0 0 0 0 0
Austin Bergstrom Intl Airport 37 57 32 58 36 / 0 0 0 0 0
New Braunfels Muni Airport 38 57 34 58 37 / 0 0 0 0 0
Burnet Muni Airport 34 54 33 55 36 / 0 0 0 0 0
Del Rio Intl Airport 39 60 39 57 42 / 0 0 0 0 0
Georgetown Muni Airport 35 55 34 56 37 / 0 0 0 0 0
Hondo Muni Airport 39 60 32 59 38 / 0 0 0 0 -
San Marcos Muni Airport 38 57 31 58 36 / 0 0 0 0 0
La Grange - Fayette Regional 39 57 32 58 37 / 0 0 0 0 0
San Antonio Intl Airport 40 58 37 57 40 / 0 0 0 0 0
Stinson Muni Airport 41 59 37 58 41 / 0 0 0 0 -




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