Area Forecast Discussion
Issued by NWS San Angelo, TX
FXUS64 KSJT 071727
Area Forecast Discussion
National Weather Service SAN ANGELO TX
1127 AM CST Wed Dec 7 2016
MVFR with occasional IFR continuing through much of the day today
across all TAF locations. May see some brief improvement this
afternoon...but a strong arctic front will be moving through in
the 0Z to 6Z time frame. Winds will shift to the north with gusts
to 25 kt possible overnight. Expecting some mixed light
precipitation will develop after 09Z and continue off and on
through about 18Z mainly KSJT southward. Not expecting significant
accumulation, but could see a little light freezing drizzle/light
snow with IFR.
.PREV DISCUSSION... /issued 553 AM CST Wed Dec 7 2016/
LIFR to IFR stratus was affecting all but the Abilene terminal
at 11Z. However expect the stratus to advect north to KABI by
14Z. IFR Stratus should scatter out mid afternoon at KSJT and
southern terminals, but return tonight as an Arctic front moves
through the region. North winds around 12 KTS can be expected as
the front initially goes through, then increase to 15 to 18 KTS
with gusts to 25 KTS...2 to 3 hours after passage. There is a
slight potential for a mixture of sleet, freezing rain and snow
after 9Z tonight.
PREV DISCUSSION... /issued 503 AM CST Wed Dec 7 2016/
(Today and Tonight)
An arctic front will move into the Big Country early evening, moving
south of the I-10 corridor by midnight. There is the potential for a
wintry mix of light sleet, light snow, and even freezing light
freezing rain late tonight as an upper level trough approaches and
mid levels of the atmosphere saturate. Precipitation amounts will be
be light, ranging from a trace to 1 or 2 hundredths of an inch. With
warm ground temperatures, little or no accumulation is expected
tonight. Surface temperatures along the I-10 corridor may not fall
below freezing until after sunrise.
Today, ahead of the arctic front, a brief warm up is expected. A
weak surface low in the Permian Basin will bring southwest winds of
5 to 10 mph late morning, which should temporarily erode low clouds
in the Concho Valley and southward in the early to mid afternoon.
High/mid level clouds, however, will increase with skies remaining
cloudy. Highs today will range from the lower 50s in the Big Country
to around 60 in the Concho Vally southward to Ozona...Sonora...
Junction and Mason.
(Thursday through Tuesday)
.Much colder Thursday into Friday and light wintry precipitation
possible on Thursday...
In the wake of the arctic frontal passage, much colder temperatures
Thursday morning will be accompanied by brisk north-northeast winds.
Wind chill readings for the morning commute to work/school will be
in the teens from San Angelo and Brownwood north across the Big
Country area. Wind chill values will be in the 20-25 degree range
across our southern counties and along the I-10 corridor.
Temperatures will not make much of a recovery during the day, and
should only climb into the lower to mid 30s during the afternoon.
Light wintry precipitation is an increased possibility on Thursday
morning across much of our area, mainly south of I-20 and north of
I-10. Broad cyclonic flow aloft will be over much of the CONUS,
with weak shortwave energy affecting our area. Will also be in the
favorable RRQ of an upper level jet. The GFS and ECMWF have
been showing light QPF in parts of our area. From an examination
of point soundings, appears that the area south of Abilene to San
Angelo and Eldorado will have a brief window (few hours) for
sufficient saturation of the column, with temperature profiles
supportive of snow. Minor snow accumulation (trace up to a few
tenths of an inch) is possible, mainly on grassy surfaces. Farther
south into the southern part of our area, a combination of light
sleet and light freezing rain will be possible, and light rain if
temperatures are still above 32 degrees at daybreak and just
prior. Overall, with the precipitation expected to be light and
with warm ground temperatures, expect minimal impacts to travel
conditions. Having mentioned this, the possibility of a few slick
spots developing on a few elevated road surfaces like
bridges/overpasses cannot be ruled out. The chance for light
precipitation will end Thursday afternoon.We are continuing with
Special Weather Statements to address this potential, along with
the upcoming arrival of the much colder air.
We are still expecting temperatures to be rather cold Thursday
night, but with an increased possibility for lingering low cloud
cover over much of the central and southern part of our area, the
temperature drop across this area should be limited by a few
degrees. Overnight lows are expected to be in upper teens/near 20
across much of the Big Country from Abilene north and east, to
around Brownwood. Clearing skies are expected across that area,
facilitating better radiational cooling. For areas farther south
and west, overnight lows should be in the 21-24 degree range.
Light winds on Friday will become southeast during the day, but
temperatures will remain cold as some cloud cover lingers. Afternoon
highs are expected to be in the 40-45 degree range.
A warming trend is in store for the weekend, with dry conditions for
our area. Gusty south winds are expected on Saturday with lee
cyclogenesis to our northwest. An upper trough is forecast to move
east across the northern and central Plains Saturday afternoon and
evening, with associated cold front pushing south across our area
Sunday morning. A quiet pattern is indicated for our area early next
week, with mostly clear skies and a warming trend to above normal
temperatures by Tuesday.
.PRELIMINARY POINT TEMPS/POPS...
Abilene 54 27 35 20 / 5 20 20 0
San Angelo 62 31 34 22 / 0 20 30 0
Junction 61 35 35 24 / 0 20 20 5
Brownwood 56 27 35 20 / 5 20 20 0
Sweetwater 55 26 33 23 / 5 20 20 5
Ozona 60 32 35 24 / 0 20 20 5