Area Forecast Discussion
Issued by NWS San Angelo, TX

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FXUS64 KSJT 290524

Area Forecast Discussion
National Weather Service SAN ANGELO TX
1124 PM CST SAT NOV 28 2015

/06Z TAFS/

Ceilings remain below 1000 feet at 0515z at most terminals. The
except to this is KSJT, where ceilings are currently near 2000
feet. Doppler radar indicates rain approaching from the west and
we expect this teminal`s ceilings to drop to around 800 feet in
the next few hours. The latest model data suggests all terminals
will maintain similar ceilings overnight and through much of much
of the day Sunday.


.PREV DISCUSSION... /issued 847 PM CST SAT NOV 28 2015/

Light rain continues to increase over West Central Texas this
evening, namely over the Big Country and western Concho Valley.
This is in response to a strong shortwave lifting northeast across
the Four Corners along with a southwesterly 140 kt jet streak.
This rain is expected to continue most of the night, likely
increasing in coverage as it progresses to the north and east.

The primary concern is the potential for light ice accumulations.
Temperatures are in the mid and upper 30s across most of the CWA,
but portions of the Big Country are hovering around 32-33 degrees.
The mesonet stations at Clyde and Sweetwater 11SW are registering
32 at this time. These sites are located a slightly higher
elevations than the Abilene and Sweetwater, and with temperatures
not expected to change much overnight, freezing temperatures
should be largely tied to locations on the Callahan Divide just
south of I-20. Light rain OR freezing rain was included from just
south of Sweetwater, to Buffalo Gap, to Clyde.

Any ice accumulations are expected to affect mainly elevated
surfaces. This includes power lines, trees, and vehicles. At the
surface, ground temperatures remain at or just above freezing and
should preclude widespread travel problems. The main area to watch
will be bridges and overpasses. Will continue the Special Weather
Statement tonight given that reasoning. The other significant
update is an increase in overnight PoPs.


PREV DISCUSSION... /issued 545 PM CST SAT NOV 28 2015/

/00Z TAFS/

Ceilings will continue to hover in the MVFR/IFR range (generally
between 800 to 1200 feet) over the next several hours. These
ceilings will drop to around 500 feet later tonight at KABI and
KSJT. Rain currently developing near KMAF and KFST will affect
these terminals after 05z. Carrying light rain at those terminals
with visibilities falling to near 2 miles after 04z. Farther
south, have inserted VCSH at the southern terminals as
precipitation timing/duration is a little more uncertain.

PREV DISCUSSION... /issued 331 PM CST SAT NOV 28 2015/

(Tonight and Sunday)

Cold rain continues tonight...

A cold airmass remains entrenched across West Central Texas this
afternoon...with light rain/drizzle continuing over much of the
area. Temperatures have "warmed" into the mid to upper 30s this
afternoon...and most of the ice in trees and on powerlines has
melted across the Big Country.

Do not expect to see much drop in temperatures overnight...with
dewpoints in the mid 30s and extensive cloud cover expected.  The
upper low will lift slowly northeast overnight...but southwesterly
flow aloft will continue with a good fetch of moisture over west
and central Texas. Will likely see light to moderate rain
redevelop overnight with isentropic upglide over the cold airmass
at the surface. Have continued with high precipitation chances
overnight...with rainfall amounts generally less than 1/2 inch.
Despite the warmer temperatures...we could still see a few patches
of ice on elevated surfaces again overnight and in the morning.
Will also see patchy fog toward there could still be
a few travel concerns in the morning. Will cover with a Special
Weather Statement.

For tomorrow...a little more improvement in temperatures, with
highs warming into the 40s by the afternoon. Still expecting lots
of cloud cover and light rain around...but this should be the last
of the precipitation for this the rain heads out
tomorrow afternoon/evening.


(Sunday night through next Saturday)

The upper low will move from the central Rockies into the central
Plains on Monday. A few lingering light rain showers are possible
in the southeastern part of our area Sunday night. Per the model
low-level moisture fields, low cloud cover will remain over our
area Sunday night and early Monday morning. Clearing skies are
expected from the west during the day Monday, with the advection
of drier air on westerly low/mid level flow. With increased
sunshine and drier air, temperatures will be appreciably warmer
Monday and should reach the lower 60s across much of the southern
half of our area.

A weak cold frontal passage early Monday night will shift winds to
the north. Temperatures will be a little cooler Tuesday, as a weak
surface high moves across the southern Plains and North Texas.

Rainfall prospects look reduced with the midweek system. An upper
shortwave trough is progged to move east across our area late
Wednesday evening. With weak lift ahead of the trough and marginal
moisture availability Tuesday into Wednesday, any rainfall in our
south and southeast counties will be light.

Dry conditions are expected for our area Thursday and Friday.
Temperatures should approach the 60 degree mark for highs Friday
with mostly sunny skies, as a shortwave ridge aloft traverses Texas.

The next rain chance may develop next weekend. An upper trough is
progged to deepen into the southwestern states, with a closed low
developing. The 12Z ECMWF is faster with progression of the upper
trough and develops the closed low over New Mexico, while the GFS
has a closed low developing just north of Las Vegas before tracking
it slowly east across Arizona and New Mexico. Although at the end
or just beyond the range of this forecast, the setup looks more
favorable with the moisture return and possibility for



Abilene  33  41  36  58 / 100  70  10  10
San Angelo  36  45  37  63 /  80  60  10   5
Junction  38  46  39  61 /  70  70  10  10


.SJT Watches/Warnings/Advisories...


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