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Area forecast discussion
National Weather Service Denver/Boulder Colorado
312 am MST Mon Jan 22 2018

Short term...(today and tonight)
issued at 312 am MST Mon Jan 22 2018

Strong winter storm will continue to move northeast today and
exit the region this morning. Radar and web cameras are showing
light snow and blowing snow over far eastern Colorado at this
time. Didn't see any blizzard conditions late this evening, so let
the Blizzard Warning expire and issued a Winter Weather Advisory
through 5am for the snow and blowing snow. Snow is expected to end
by 12z. Conditions are slowing improving and expect to let the
advisory expire at 5am. Gusty northwest winds will continue to
produce areas of blowing snow into the morning hours.

Northwest flow aloft will keep temperatures cool today with highs
in the 30s to lower 40s over northeast Colorado. Light snow will
be possible over the mountains this morning before drier air moves
in. A weak wave embedded in the flow aloft will increase mid
level moisture tonight. This is expected to produce snow showers
in the mountains. Meanwhile, the lower elevations will remain dry.
Northwest facing slopes may see up to 3 inches of snow overnight.

Long term...(tuesday through sunday)
issued at 312 am MST Mon Jan 22 2018

A weak shortwave trough moved along by 45-60 kt nwly mid-level
flow is still forecast to pass over north central and northeast
Colorado Tuesday morning. Models show the bulk of the q-g ascent
and instability with this system...albeit weak...passing to our
north Tuesday morning. And, yet many of the models continue to
generate light quantitative precipitation forecast...about a tenth of an inch or so...over the
northern mtn ranges by midday. Appears orographics and cold air advection will be
the primary producers of snow with this system, and the snowfall
that manages to form will probably be scattered over the higher
terrain where an inch or so of snow is possible. Elsewhere,
downslope flow off the Front Range mtns will keep the plains dry
on Tuesday, although cannot rule out a stray snow shower or two
across the far northeast corner of the state before noon on
Tuesday as the trough passes overhead. Otherwise a cool day
Tuesday with temperatures running 2-5 deg f below average.

On Wednesday warm-up begins as heights rise with an upper level
building to our west. A low-level southwesterly downslope flow
will also add to warming on the plains. Could see Max temps jump
at least 10 deg f from the day before, and with the upper ridge
passing on Thursday, could see another 4-7 degs added to that.
May also become a bit more breezy in the mtns and along the
Palmer Divide. Nothing terribly strong, but mtn tops could see
southwest winds approaching 45 mph by the afternoon.

All this warming and wind will precede our next storm system to
swing down across the region on Friday. It now does not look as
impressive in the models as it did yesterday. Models show this
system remaining an open wave with the bulk of its energy and
moisture passing over Wyoming. Could see some snow and gusty winds
in the high country, and perhaps a shower or two moving off the
Front Range and out over the plains. Once the trough axis passes
by late on Friday, could see several hours of gusty bora-type
winds in and near the Front Range foothills Friday night. Except
for a few lingering snow showers in the high country Saturday, the
weekend looks dry with below average temps to start and near
average temps on Sunday.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 312 am MST Mon Jan 22 2018

VFR conditions will prevail through tonight. Clouds will continue
to decrease with mostly sunny skies prevailing today. Mid and
high clouds will increase tonight with passage of a weak system.
There is a slight chance ceilings fall as low as 6000 feet. A
westerly wind component will persist today and then turn southerly
around 02z. Winds speeds are expected to stay under 20 knots.


Bou watches/warnings/advisories...
Winter Weather Advisory until 5 am MST early this morning for



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