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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
1009 am MST Monday Nov 30 2015

issued at 1005 am MST Monday Nov 30 2015

The satellite pictures put the center of the upper closed low now
getting into south central Nebraska. There is still some light
snow falling over the eastern border counties of the County Warning Area right
now. The winds are pretty light and variable over most of the
County Warning Area...however the far east does have 10-25 knot northwesterlies.
The orographic enhanced snows in the mountains have not kick in
yet. Will adjust some grids with the exiting storm at hand.


Short term...(today and tonight)
issued at 329 am MST Monday Nov 30 2015

An upper low over central Wyoming is swinging a lobe of energy across
the state right now continuing to bring snow to northeastern
and north central Colorado. This lobe will be quickly exiting the
area to the east with strong downward qg vertical motion moving in
behind. This will shut off snow from southwest to northeast this
morning...with only a slight chance of snow over the far northeast
corner by noon. Expect an inch or less of additional accumulation
over the plains...with the greatest amounts toward the NE and Kansas
borders. Clouds will be clearing as well this morning from the
foothills east to the state border by the late afternoon.
Temperatures today will be slightly warmer today over yesterdays
readings as the storm system exits and skies clear...generally
right around 30 for the plains.

Snow over the mountains will decrease this morning...then increase
across the high slopes through the afternoon and evening as winds
aloft switch from southwesterly to the orographically favored
northwest direction. Expect another 1 to 3 inches today over the
higher peaks then another inch or two tonight.

As the storm system heads further east...high surface pressure
builds over western Colorado and our area ends up under the left
entrance region of a jet streak....west winds will begin to
increase late this afternoon and especially tonight. Cross
sections show 50 knots mountain top winds with a mean state critical
layer above...helping to force these winds down the east of the
Front Range mountains and foothills. Look for gusty west winds 25 to
40 miles per hour sustained with gusts to 60 miles per hour tonight. This will create
areas of blowing snow in the aforementioned areas as well as down
into the far western urban corridor.

Long term...(tuesday through sunday)
issued at 329 am MST Monday Nov 30 2015

Strong and gusty winds will continue into Tuesday morning in/next
to the Front Range mountains and foothills. Cross sections now
indicate the development of a mean state critical layer...remaining
in place through most of the day. This would allow normally
vertically propagating wave energy to be deflected and enhanced
at the surface. Even with 30-35 knots of Cross Mountain component
could see gusts in this regime reach the 60 plus knot range in
wind prone areas...approaching high wind criteria. The gusty winds
will produce areas of blowing snow from the mountains and
foothills across the nearby adjacent plains including Highway 93
between Boulder and Golden. Park County will also be susceptible
to blowing snow given the fresh snowfall there. Winds are expected
to gradually weaken Tuesday afternoon into Tuesday evening as flow
aloft begins to diminish.

Otherwise...look for dry conditions through Friday with a gradual
warming trend and lighter winds. Highs in the upper 30s and lower
40s on the plains Tuesday should rise into the lower to middle 50s
and possibly even warmer by Friday with continued warm advection
and Lee troughing.

By this weekend...a weak upper level trough is expected to move
into the region. This should bring cooler temperatures and just a
slight chance of snow showers. All models continue to show this
system being relatively moisture starved...with only the European model (ecmwf)
showing much threat of light precipitation on the plains. Thats
just enough to warrant some low probability of precipitation for now.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 944 am MST Monday Nov 30 2015

Ceilings are slow in lifting at the big Airport. May need to keep
some in the broken-2- to bkn040 range well into the afternoon
hours...say 21z. No more visibility restriction however. Winds are
expected to remain light the rest of the day with varying


Bou watches/warnings/advisories...


short term...kriederman
long term...barjenbruch

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