Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 281721

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1021 AM MST Mon Nov 28 2016

.SHORT TERM...(This afternoon through Tuesday)
Issued at 1020 AM MST Mon Nov 28 2016

Forecast on track with an increase in snowfall expected across the
mountains this afternoon and evening. Radar returns are already
beginning to increase across western Colorado as short wave
approaches from the northwest. Snowfall amounts this morning were
only around 1 inch, but should see another 1-4 this afternoon as
short wave, deeper moisture, and higher lapse rates move in. The
heavier snow rates should remain in place through the evening with
better orographic contribution as winds shift more northwesterly.
Moisture depth decreases later tonight but snow will continue with
modest orographics holding in place. Did bump up snow amounts an
inch or so tonight given the improved orographics and local
orographic snow model output.

The plains will remain mainly dry, with breezy to windy
conditions expected at times. Peak gusts already near 40 mph over
the plains and those should continue the rest of the afternoon.
Meanwhile, some areas closer to the Front Range are seeing lighter
winds like around Fort Collins and Greeley where airmass is not
yet fully mixed.

.LONG TERM...(Tuesday through Sunday)
Issued at 241 AM MST Mon Nov 28 2016

Northwest flow aloft around a low over the Northern Plains will
prevail over Colorado Tuesday. The northwest flow combined with
moisture over the mountains will keep orographic snow going over
north central Colorado. Up to an additional 4 inches of snow will
be possible in orographic favored areas. For the Front Range and
eastern plains, it will be windy. The strongest winds will be
found over the northeast corner of Colorado where northwest winds
around a strong low over the Northern Plains could bring wind
gusts to 50 mph. The northwest flow will also usher in cooler air
with highs in the 30s expected across northeast Colorado.

Northwest flow aloft will continue Tuesday night and Wednesday.
This will keep cool air over Colorado. Light snow/flurries will
remain possible over the mountains. Any new snowfall Tuesday night
and Wednesday is expected to be light.

Weak ridging will move across Colorado Wednesday night and early
Thursday as an upper level trough dives south across the western
states. This will bring dry conditions. Temperatures will remain
cool with highs in the 30s over northeast Colorado.

Flow aloft will be southwesterly late Thursday and become light
Friday as the upper level low drops into the Desert Southwest.
Still a good amount of uncertainty among the models on the track
of the upper level low. This system could bring light snow to the
mountains if it tracks far enough east. Models also showing this
system dragging a cold front south across eastern Colorado
sometime late in the week. Will have low pops in the forecast for
this. Moisture will be limited, so expected precipitation amounts
to the be light. Temperatures will remain cool.

For the weekend, models are not in great agreement but they are
trending towards a northwest flow aloft with possible ridging.
This favors dry conditions and warming temperatures at this time.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1020 AM MST Mon Nov 28 2016

West/northwest winds with speeds of 10-18 knots with peak gusts
in the 20-30 knots range should should contine at the Front Range
airports into the afternoon before decrease toward 23Z-00Z. Then
winds will become lighter with speeds 8-12 knots and no
significant gusts expected after 00Z. Otherwise VFR conditions
expected to prevail.


Winter Weather Advisory until 5 AM MST Tuesday for COZ033-034.

Winter Storm Warning until 5 AM MST Tuesday for COZ031.



SHORT TERM...Barjenbruch
AVIATION...Barjenbruch is the U.S. government's official web portal to all federal, state and local government web resources and services.