Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 281740

Area Forecast Discussion
National Weather Service Grand Junction CO
1040 AM MST Mon Nov 28 2016

Issued at 1040 AM MST Mon Nov 28 2016

Added UTZ028 to a Winter Weather Advisory in effect now until
Tuesday morning. The La Sal mountains in southeast Utah look
favored for periods of heavy snowfall in this northwest flow with
the next disturbance approaching the area and moving through this
afternoon and evening. Currently thinking 5 to 10 inches of snow
looks likely for the La Sals today with lesser amounts of 3 to 6
inches in the Abajo mountains. Kept this advisory above 8000 feet
and did not include the Highway 191 corridor through Monticello.
Only expecting an inch or less here and little impact with road
accumulations minimal. Updated grids through Tuesday morning to
reflect current and latest trends. Also, enhanced pops and snow
amts a bit tonight through Tuesday morning in the Uncompaghre
Gorge area in the northwest San Juans as this area will be favored
for heavier snowfall as the flow shifts to northerly.


.SHORT TERM...(Today through Tuesday)
Issued at 223 AM MST Mon Nov 28 2016

The last wave to affect the area is now exiting the region though
favorable northwest flow will allow orographics to keep snowfall
in the picture over the higher terrain. From now until about
noon, a downturn in intensity and coverage is expected as
widespread lift decreases. QG Omega and cross sections agree
showing minimal lift.

The next wave has already set its sights on eastern Utah and
western Colorado, however. Infrared and water vapor imagery
clearly show this next wave already dropping down into Nevada and
Utah and reaching our area from about midmorning onwards.

By noon today, the next shot of snowfall will begin and
persist through Tuesday morning. Cross sections show the highest
omega values through and above the dendritic growth region which
should make for some efficient snow making. Some of our southern
advisories and warnings were set to expire this morning but
instead of dropping them, went ahead and extended them through
Tuesday morning. Granted, there will be a break in snowfall for
quite a few areas but it shouldn`t last long, a short 6 hours or
so, before the snow gets going again. Northwest slopes of the San
Juans will get the most snow from this wave with a gorge event
certainly possible. As far as the Upper Gunnison Valley, areas to
the west of Gunnison will be favored especially Cerro Summit and
the Blue Mesa areas. Snowfall amounts with this next wave look to
be on the order of 6 to 10 inches with higher amounts possible.
Once the storm is finally over, storm total snowfall amounts will
probably be pretty impressive!

By daybreak tomorrow morning, most energy will have shifted to
our east with models highlighting only the northern and central
mountains seeing any appreciable snow. The warnings and advisories
for the San Juans, Gunnison area, and Uncompahgre will expire at
6AM while the remaining highlights will end at noon. They can be
pulled down sooner, if needed. For the rest of Tuesday, plenty of
clouds will remain with only some light snowshowers to contend

As far as temperatures are concerned, each wave continues to bring
in colder air so expect high temperatures anywhere from 5 to 10
degrees below normal.

.LONG TERM...(Tuesday through Sunday)
Issued at 334 PM MST Sun Nov 27 2016

Precipitation will generally favor areas north of I-70 Tuesday
with showers lingering along the Colorado Divide through early
Wednesday. Looking at the forecast for the rest of the work
week...a transition to west-northwesterly flow aloft will bring a
return to dry and near seasonal weather for the rest of Wednesday
and Thursday. Long-range models begin to diverge after this
period: the GFS shows a cutoff low dropping into the Great Basin
early Friday while the Euro keeps it as an open wave. Until we see
better model agreement, have gone ahead and kept POPs conservative
for the latter half of the week with a chance for some mountain


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 940 AM MST Mon Nov 28 2016

The brief break in precipitation is coming to an end this morning
as the final round of snow with the current storm system moves in
from the northwest. MVFR and occasional IFR conditions are likely
this afternoon and early evening with Ceilings at or below 1kft at
RIL, EGE, ASE, and TEX. Valley terminals may also see reduced
visibility at times through 0z with snow showers to the valley


CO...Winter Weather Advisory until 6 AM MST Tuesday for COZ014-017.

     Winter Storm Warning until noon MST Tuesday for COZ004-009-010-

     Winter Storm Warning until 6 AM MST Tuesday for COZ018-019.

     Winter Weather Advisory until noon MST Tuesday for COZ002-003-

UT...Winter Weather Advisory until 6 AM MST Tuesday for UTZ028.



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