Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 281017

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

.SHORT TERM...(Today and tonight)
Issued at 241 AM MST Mon Nov 28 2016

The flow aloft will remain northwesterly through tonight. The next
disturbance embedded in the flow aloft will drop out of the
northern Rockies and move north to south across western Colorado
this afternoon and evening. Best mid level QG ascent will be
around 00z so could see snowfall pick up around that time. Prior
to that, there will be weak subsidence this morning associated
with a short wave ridge. Similar circumstances will occur after
midnight tonight. No changes regarding the current highlights at
this time. Gusty northwesterly winds in the 40-50 mph range will
continue above timberline today, then weaken tonight. Across the
northeast plains of Colorado, cool and dry with just a slight
chance of snow along the Wyoming border late tonight.

.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 12Z TAFS through 12Z Tuesday morning)
Issued at 241 AM MST Mon Nov 28 2016

VFR conditions should persist through 12z Tuesday morning.
Primarly west/northwest surface winds through much of the period
strongest late this morning and afternoon, 10-15 kts at KDEN and
KAPA with 15-20kts at KBJC. Otherwise wind speeds will be in the
4-8kt range.


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

Winter Storm Warning until 5 AM MST Tuesday for COZ031.



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