Area Forecast Discussion
Issued by NWS Austin/San Antonio, TX

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS64 KEWX 230445
AFDEWX

Area Forecast Discussion
National Weather Service Austin/San Antonio TX
1045 PM CST Sun Nov 22 2020

.AVIATION.../06z TAFs/
Not much change to the ongoing TAF forecast. AUS and SAT are already
MVFR so have indicated the earlier onset there. Also bumped up MVFR
beginning at SSF to 07z. The rest of the Sunday night and Monday
morning forecast remains the same with ceilings dropping to IFR by
14z across South Central Texas, then gradually improving through late
morning and into early afternoon Monday. Ceilings should remain, but
now look to rise briefly to VFR Monday evening, before MVFR sets in
again Monday night with the return of southerly flow. Northerly winds
have been gusty this evening, but should calm by the morning and
then turn easterly and eventually southeasterly through the day on
Monday.

&&

.PREV DISCUSSION... /ISSUED 538 PM CST Sun Nov 22 2020/

AVIATION.../00z TAFs/
VFR conditions continue across South Central Texas this afternoon.
The front currently bisects South Central Texas and will continue the
southward progression through the evening and early overnight hours.
Weak easterly winds persist ahead of the front, with north winds
gusty at times prevail behind the front. GOES satellite images show a
decent cloud shield behind the front so think that MVFR cigs will
build in between 08z and 10z tonight, with period of IFR ceilings
beginning between 13z and 14z. Models have also become more bullish
keeping clouds around for most of Monday. Based on this have improved
all terminals to MVFR by 18z, but believe these ceilings will stick
around through the reminder of the TAF period while winds go back
easterly and eventually southeasterly. There are a few showers around
this evening, with additional showers possible overnight, but they
are very sparse and should have little to no impact at the terminals
so no precipitation has been mentioned in the TAFs.

PREV DISCUSSION... /ISSUED 138 PM CST Sun Nov 22 2020/

SHORT TERM (Tonight through Monday Night)...

A weak cold front sits just north of our CWA currently. A general
consensus was for the front push farther into South Central Texas
before dissolving. There has been very little progression with this
front this morning and early afternoon. Deep moisture has allowed for
light shower activity in our eastern counties, as well as along the
front. As clouds scatter out in some areas this afternoon ahead of
the front, widespread low clouds will be carried in behind the front
as it slowly progresses. Northeasterly winds behind the front will
bring in slightly drier and cooler air, though not enough for any
long term lowered temperatures. Tonight, lows in the 50s with mostly
cloudy skies. Tomorrow, the winds return back out of the southeast,
and temperatures will have only dropped a few degrees with highs in
the low 70s in the Hill Country and mid to upper 70, elsewhere.
Tomorrow night, the abundant return of moisture will bring back
patchy fog overnight.

LONG TERM (Tuesday through Sunday)...

Tuesday morning, the upper level pattern is expected to consist of
ridging over the OH Valley and a trough pushing across the Rockies.
In response to this trough, ongoing lee cyclogenesis will lead to
strengthening southerly flow over south-central TX. Some isolated
streamer shower activity is possible in the morning over the Hill
Country and along and east of I-35. Breezy conditions are expected
during the day with sustained 10-20 mph southerly winds gusting to
25-30 mph, and this will help bring well-above normal temperatures
into the 75-85 degree range.

As the low pushes across the Plains towards the Great Lakes Tuesday
night and Wednesday, it will send a cold front across our region.
NAM frontal timing suggests the front will be about halfway through
the CWA at 12Z Wed. Some shower activity is possible along the front
mainly east of I-35 in the early morning, and an isolated
thunderstorm cannot be ruled out across our far eastern zones, but
in general its not expected to bring much in the way of
precipitation. Cooler highs in the upper 60s to near 80, then
overnight lows into the 40s and lower 50s for Thanksgiving morning.

By Thursday afternoon, as post-frontal high pressure exits to the
northeast, southerly flow will begin to return and as a result temps
will again warm into the 70s and lower 80s for most on Thanksgiving
Day and Friday. Another, more potent trough and cold front are
expected to move across the central US on Friday and Friday night,
this time with better chances for appreciable rainfall (>0.5")
across primarily eastern portions of the region ahead of and along
the front.

While confidence is moderate to high in cooler temperatures for next
weekend, confidence in rainfall is lower due to the tendency for
global guidance to overestimate precip this far south after day 5.
Could be our best chance for thunderstorm activity in over two
months, but no guarantee right now. At this time, the GFS solution
has become more progressive, with the front and any associated precip
long gone by sunrise Saturday, while the ECMWF and CMC are both
slower with this system and thus keep precipitation in the forecast
into the early part of next weekend. Any rain we can get would be
quite helpful, but it appears chances are very slim for any notable
accumulations across the areas that need it most (west of San
Antonio) over the next 7 days. Either way, overnight lows Sunday and
Monday morning next week will again dip into the 30s over the Hill
Country.

PREV DISCUSSION... /ISSUED 1120 AM CST Sun Nov 22 2020/

AVIATION...
Widespread, multi-layered clouds are draped across Texas. Terminals
are slowly recovering from IFR conditions from this morning. A slow
improvement over the next couple of hours will then be short-lived.
A weak front will reach the area later this afternoon and give a more
easterly wind component. AUS looks to be the only site that has a
shot of a stray shower with this front this afternoon, but with
minimal chances have left out the mention of precip in the TAF.
Anticipating another round of low stratus overnight tonight with
IFR/MVFR ceilings building in.

&&

.PRELIMINARY POINT TEMPS/POPS...
Austin Camp Mabry              76  53  72  61  80 /  20  -    0  -   10
Austin Bergstrom Intl Airport  77  52  74  60  81 /  20  -    0  -   10
New Braunfels Muni Airport     80  56  77  63  84 /  10  10   0  -   10
Burnet Muni Airport            74  50  69  60  78 /  20  -   -   -   10
Del Rio Intl Airport           79  60  77  63  84 /  -   20  10  -    0
Georgetown Muni Airport        76  50  71  59  79 /  20  -    0   0  10
Hondo Muni Airport             79  55  77  61  84 /  -   10  -   -   10
San Marcos Muni Airport        78  53  75  60  81 /  10  10   0  -   10
La Grange - Fayette Regional   79  55  76  61  81 /  20  -    0   0  10
San Antonio Intl Airport       79  55  75  63  81 /  10  10   0  10  10
Stinson Muni Airport           79  56  77  63  83 /  10  10   0  10  10

&&

.EWX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

Short-Term/Aviation...Treadway
Long-Term...05


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.