Area Forecast Discussion
Issued by NWS San Angelo, TX
FXUS64 KSJT 200512
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1112 PM CST Fri Dec 19 2014
Stratus will continue to spread over the area through tomorrow
morning accompanied by MVFR ceilings. Visibilities will begin to
degrade over the area by 09Z...lowering to 2SM or less around 12Z.
Visibilities will begin to clear and ceilings will lift to VFR
.PREV DISCUSSION... /ISSUED 722 PM CST FRI DEC 19 2014/
Will update to increase clouds overnight, and to warm lows up a
degree or two. Patchy areas of fog, mainly 3 to 5 miles is also
possible towards morning...with the best potential along the I-10
corridor, Mason and Menard counties.
PREV DISCUSSION... /ISSUED 514 PM CST Fri Dec 19 2014/
The southern-most terminals have improved to VFR the last several
hours. However, stratus will redevelop this evening and return all
terminals to MVFR through the remainder of the evening and through
tomorrow morning. Winds will remain light and variable through the
PREV DISCUSSION... /ISSUED 401 PM CST Fri Dec 19 2014/
(Tonight and Saturday)
The visible satellite imagery was showing stratus across much of the
northern 2/3 of West Central Texas. The southern 1/3 of the area is
mostly clear. Temperatures were cool due to mainly the low clouds,
with readings in the mid to upper 40s. However, Sonora has warmed
into the upper 50s.
For tonight, the main challenge will be how the low clouds set up.
The NAM and GFS models indicate moisture surging back to the west at
925 MB between the 06Z to 12Z time frame. Looks like the Big Country
will pretty much remain cloudy due to current satellite trends. Low
clouds will increase again across the remainder of the area,
especially along the I-10 corridor which is currently mostly clear.
A shallow cool airmass will result in temperatures falling into the
mid and upper 30s by Saturday morning.
For Saturday, expect widespread low clouds across much of the area
during the morning hours. There will be some breaks in the clouds by
the afternoon and possibly mostly sunny across the western 1/3 of
the area. Highs will be in the 50s.
(Saturday night through Friday)
Seasonably mild to warm temperatures will continue through Christmas
Day. A shortwave trough and associated vort max approaching the
region from our west Saturday night, will cross the area on Sunday.
A weak cold front will also drop south during the day Monday. None
of these features are expected to bring any rainfall to the area.
Westerly surface winds ahead of the cold front will result in a
down-sloping wind across the area. This, combined with compressional
heating, will allow gusty winds to develop. This will help warm
temperatures to near 70 degrees, with the warmest readings/higher
wind gusts across the western half of the area. For Monday
night/Tuesday, a vort max rounding the base of a Central Plains
trough will pass by to our north/east. This may generate enough
forcing for a few showers to develop. The models have come into
better agreement with this. Thus, showers were added to the
forecast for areas along/north of Interstate 20; this matches
well with surrounding offices.
For the middle to end of the week, a progressive shortwave trough
will cross the region and strengthen some as it crosses the Central
Plains by week`s end. A strong vort max in the base of the trough
will be crossing Arizona Thursday, which will dampen out as it
lifts east/northeast away from West Central Texas Friday, sending
a weak cold front south towards the area. Similar to earlier in
the week, compressional heating ahead of this front and a
southwest wind with its associated down-sloping effect, will again
warm temperatures for Christmas Day. Thus, highs near 70 degrees
.PRELIMINARY POINT TEMPS/POPS...
Abilene 46 38 54 42 60 / 10 5 5 5 5
San Angelo 51 36 58 42 63 / 10 5 5 5 5
Junction 55 37 58 40 60 / 10 5 5 5 5