Area Forecast Discussion
Issued by NWS San Angelo, TX
FXUS64 KSJT 190538
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
1138 PM CST THU DEC 18 2014
Forecast flight conditions are poor for the next 12-15 hours.
Ceilings between 400-1200 ft across most of the CWA have resulted
IFR conditions as of 05z. Visibilities are currently greater than 6
miles, but are forecast to diminish to 2-5 miles later tonight and
early Friday. Scattered light rain showers have developed south of
I-10 near the KSOA and KBBD terminals and will move to the north
and east overnight. The bet chance of rain will be at the KSOA,
KJCT, and KBBD sites, with only VCSH mentioned at KABI and KSJT.
As the shortwave trough axis moves east of the area (mid morning),
rain chances will shift east with ceilings gradually improving
throughout the day. IFR conditions are expected to persist through
late morning, with possible VFR conditions by late afternoon.
Expect light northeast to north winds throughout the TAF period.
.PREV DISCUSSION... /ISSUED 551 PM CST THU DEC 18 2014/
Flight conditions will deteriorate through the next 24 hours at all
terminals. We expect ceilings to drop to 700 feet with visibilities
as low as 2 miles at KSOA, KJCT, and KBBD, where rain is expected
with a few thunderstorms possible. The thunderstorms weren`t
included in the TAFs due to timing/location uncertainties. For KSJT
and KABI, ceilings will drop to 700 feet. However, these areas will
have a more showery nature to any rainfall, helping keep
visibilities at/above 4 miles.
PREV DISCUSSION... /ISSUED 348 PM CST THU DEC 18 2014/
(Tonight and Friday)
A weak cold front was moving south across the Big Country counties
this afternoon and will continue south across the rest of the area
through early evening. Meanwhile, a shortwave trough/upper level
disturbance was moving across the Desert Southwest and will track
east across the area late tonight and early Friday. Isentropic
ascent north of the front will increase this evening, with synoptic
scale lift increasing overnight as the aforementioned shortwave
approaches. This will lead to thickening and lowering cloud cover
this evening, with a chance for rainfall across the area overnight
The best chance for measurable precipitation will be across
southeast counties, where rainfall amounts between 1/4 and 1/2 inch
will be possible. Elsewhere, rainfall amounts should be light,
generally between 1/10 and 1/4 inch. Mid level lapse rates still
look steep enough for some isolated thunder across southern sections
after midnight and this was retained in the forecast. Lows tonight
will be in the 40s, with light northeast winds.
The upper level trough axis will move across the area Friday
afternoon, with precipitation ending from west to east. It will
be mostly cloudy and considerably cooler, with highs ranging from
the upper 40s north, to the lower and middle 50s elsewhere.
(Friday Night through Christmas Day)
Looks like a dry forecast and mainly above normal temperatures this
weekend through Christmas Day. Upper level west-northwest flow will
dominate with a only dry cool front moving through the area Monday
night. Highs will be in the upper 50s and 60s, with possibly a few
lower 70s Monday. Lows will be in the 30s and 40s.
.PRELIMINARY POINT TEMPS/POPS...
Abilene 42 49 35 55 38 / 30 30 5 5 5
San Angelo 45 54 35 59 38 / 40 30 5 5 5
Junction 48 56 37 60 39 / 70 50 0 5 5