Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 130722

Area Forecast Discussion
National Weather Service Grand Junction CO
1222 AM MST Fri Jan 13 2017

Fixed all capitals in update.

UPDATE Issued at 1000 PM MST Thu Jan 12 2017

Snow continues to fall in Meeker and Craig according to local
webcams and calls to local emergency personnel. Radar shows what
looks like more bands to the south which matches up well with 00Z
NAM guidance. Plenty of new snow on the roads so certainly expect
some impacts in the morning. For these reasons, advisory has been
issued for zone 2 for 2 to 4 inches with higher amounts along the
Wyoming border through early Friday afternoon.

UPDATE Issued at 1000 PM MST Thu Jan 12 2017

Snow showers have tapered off across the eastern Uinta Basin with
areas of fog moving in. May see a few more showers lift north across
the basin later tonight, but significant accumulations are no
longer expected. Band of heavier snowfall will remain in place
across the mountains of east central Utah and western Colorado
through the early morning hours with scattered showers in the
valleys. Current mountain highlights look reasonable with new 00Z
NAM backing off heavier accumulations across our central zones.


.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 06Z TAFS through 06Z Friday night)
Issued at 1000 PM MST Thu Jan 12 2017

Strong upper level low pressure system just west of California
will drop south into the northern Baja region over the next 48
hours. Moisture wrapping around this low pressure system will
continue to impact aviation interests across our area with rain
and snow showers generating ceilings below ILS breakpoints with
areas of MVFR to IFR conditions as well. Focus of the heaviest
precipitation will shift south after 00z/Sat with slowly
improving ceilings expected north of Interstate 70. Mountains will
remain obscured in low clouds and snow showers.


CO...Winter Weather Advisory until 2 PM MST this afternoon for

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

     Winter Storm Warning until 5 PM MST Saturday for COZ019.

UT...Winter Weather Advisory until 2 PM MST this afternoon for UTZ025.

     Winter Storm Warning until 5 PM MST this afternoon for UTZ028.



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