Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 122300

Area Forecast Discussion
National Weather Service Grand Junction CO
400 PM MST Thu Jan 12 2017

.SHORT TERM...(Tonight through Friday night)
Issued at 400 PM MST Thu Jan 12 2017

Latest IR satellite this afternoon shows a well defined stream of
moisture moving in from the southwest. This has resulted in steady
showers across northern portions of our forecast area over the
past several hours; northeast Utah in particular. An area of low
pressure over California will continue to drop south over the
next few days with models keeping the center of it well out of
our forecast area. We will still feel the effects of this system,
though, as the low keeps pumping moisture into the forecast area
through the short term and into the long term period. In
particular, the abundance of moisture will keep skies overcast and
allow overnight lows tonight to warm slightly.

As far as highlights go, made no changes to the winter advisories
and warnings issued late this morning. Showers will taper off in
the eastern Uinta Basin this evening, so the Winter Weather
Advisory should still be able to drop at 11 pm. Coverage and snowfall
rates will pick up over the northern and central mountains tonight
and early Friday morning with high-resolution models picking up
on a band stretching across I-70. Overall, accumulations on the
magnitude of 6 to 12 inches are expected for these areas through
Friday. Locally higher amounts will be possible, especially at
elevations above 9000ft and on western and southern facing
slopes. Lighter accumulations are expected in the San Juans
tonight and Friday before the heavier precipitation arrives Friday
night into Saturday.

.LONG TERM...(Saturday through Thursday)
Issued at 400 PM MST Thu Jan 12 2017

By Saturday, the aforementioned closed low will be south of the
CONUS and start to move back inland on Sunday. The track of this
low will allow for showers to wind down over the northern
mountains Saturday morning while activity persists over the
central and southern mountains. An additional 5 to 10 inches will
fall over the southwest San Juan mountains Friday night and
Saturday. Additional accumulations greater than 12 inches will be
possible above 10000ft, resulting in storm total snowfall
exceeding two feet.

The low will progress across the Texas panhandle by the beginning
of the work week with some wraparound moisture resulting in
lingering showers down south. Weak transitory ridging builds
across the area on Wednesday seeing the return of benign weather
for the first time in a while! This break will be short-lived,
however, as a broad upper level trough moves onshore and brings an
increased chance for clouds and showers for the latter half of the
work week.


.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1043 AM MST Thu Jan 12 2017

Moist upper level west southwest flow is interacting with a
surface boundary to support mid and high clouds across the
forecast area today. A threat of rain for the lower elevations and
mountain snow, heavy at times, will prevail at a majority of the
terminals through the overnight hours. Otherwise anticipate MVFR
to VFR conditions to prevail through the next 24 hours.

Forecast confidence is moderate to high.


CO...Winter Weather Advisory until 5 PM MST Saturday for COZ009-012-

     Winter Storm Warning until 5 PM MST Saturday for COZ019.

     Winter Weather Advisory until 2 PM MST Friday for COZ003-004-013.

UT...Winter Weather Advisory until 2 PM MST Friday for UTZ025.

     Winter Weather Advisory until 11 PM MST this evening for UTZ024.

     Winter Storm Warning until 5 PM MST Friday for UTZ028.



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