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Area forecast discussion 
National Weather Service Austin/San Antonio Texas
1111 PM CST Sat Dec 3 2016

Aviation...
not much change from previous taf package. IFR/LIFR will be the
most likely flying categories at all area airports for the next
24 hours. There will also likely be off and on rain into the
afternoon Sunday. It shouldn't have much effect on category.

&&

Previous discussion... /issued 949 PM CST Sat Dec 3 2016/

Update...
the upper level pressure system currently over northwest Mexico is
forecast to push to the southeast while sending several short-
waves overnight across our area. Latest hrrr and NSSL-wfr models
show convective initiation overnight into Sunday morning with
storms starting across the southwest counties/coastal plains area
and then moving and expanding across the I-35 corridor. With this
newly round of moderate to heavy showers possible affecting same
areas that received 3 to 5 inches of rainfall last night through
late this morning, we opted to issue a Flash Flood Watch which is
in effect through late Sunday night. As the upper low pushes
across the Rio Grande plains Sunday evening, yet another round of
moderate to heavy showers is expected along and east of I-35
Sunday evening into Monday morning. Weather conditions will
improve Monday west to east as the upper low moves into central
Texas.

Previous discussion... /issued 342 PM CST Sat Dec 3 2016/

Short term (tonight through Monday night)...
widespread light to moderate rain showers along with a few
thunderstorms continue across most of south central Texas this
afternoon. Radar trends do show a slight decrease in this activity
across the Rio Grande plains and southern Edwards Plateau. We do
expect a slight decrease in rainfall this afternoon and evening,
with mainly light rain expected. However, another round of
moderate to locally heavy rainfall is expected beginning late this
evening into early Sunday morning as the upper low over the
central Baja Peninsula nudges eastward. As deep layer forcing for
ascent spreads into the region, we expect an increase in coverage
of showers and thunderstorms. A brief lull in the activity is
expected Sunday afternoon before another round of lift moves
through with the main upper low. This should bring another round
of moderate to locally heavy rainfall to the region beginning
Sunday evening and continuing into early Monday morning. Given
saturated soils across the central portion of our area and
expected periods of heavy rainfall through Monday morning, we have
issued a Flash Flood Watch for portions of south central Texas.
The watch extends as far west as Bandera and Medina counties
eastward through the San Antonio Metro area into the Highway 77
corridor. Total rainfall amounts of 1 to 2 inches with isolated
amounts up to 4 inches are possible in the watch area from late
tonight into early Monday morning. The main upper low will move
east of the region on Monday and we will see a quick end to the
precipitation from southwest to northeast by early evening.

Long term (tuesday through saturday)...
westerly flow aloft behind the departing upper low along with
sunny skies and northwesterly downslope winds will allow a brief
warming and drying trend to take place on Tuesday. On Wednesday,
we should see enough moisture return to warrant a slight chance
for showers generally along and east of I-35. A weak cold front
along with an increase in cloud cover will also work to knock
temperatures back closer to climatological normals. A much
stronger cold front will move through Wednesday night bringing
gusty north winds and much cooler air to the region. Daytime highs
on Thursday and Friday will likely remain in the 40s to near 50
for most areas. We also expect good potential for a widespread
freeze Thursday night and Friday night across a good portion of
south central Texas. High temperatures are expected to remain
below normal on Saturday.

&&

Preliminary point temps/pops...
Austin Camp Mabry 48 54 47 58 46 / 100 80 90 60 -
Austin Bergstrom Intl Airport 48 53 47 58 44 / 100 80 90 60 -
New Braunfels Muni Airport 49 53 48 60 45 / 80 90 90 50 -
Burnet Muni Airport 46 51 44 54 43 / 80 70 90 70 -
del Rio Intl Airport 51 53 47 62 44 / 50 80 80 30 0
Georgetown Muni Airport 47 52 46 55 44 / 100 80 90 70 -
Hondo Muni Airport 50 55 47 62 43 / 40 90 90 30 -
San Marcos Muni Airport 48 54 48 59 45 / 90 90 90 50 -
La Grange - Fayette regional 49 54 49 58 46 / 90 90 90 50 -
San Antonio Intl Airport 50 54 49 60 47 / 80 90 90 40 -
Stinson Muni Airport 51 55 49 61 46 / 80 90 90 40 -

&&

Ewx watches/warnings/advisories...
Flash Flood Watch through late Sunday night for the following
counties: Bandera...Bastrop...Bexar...Caldwell...Comal...Fayette...
Gonzales...Guadalupe...Lavaca...Lee...Medina...Wilson.

&&

$$

Mesoscale/aviation...05
synoptic/grids...17
public service/data collection...Williams

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