Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 280314

Area Forecast Discussion
National Weather Service Denver/Boulder CO
814 PM MST Mon Feb 27 2017

Issued at 759 PM MST Mon Feb 27 2017

Some mtn areas north of I-70 have been receiving decent snow in
swly flow. With upper lvl jet fcst to remain in place overnight
could see some banded pcpn enhancing snow amounts so will issue an
advisory for zns 31 and 33. Axis of jet is fcst to shift a bit
further south late tonight so snow should increase in mtn areas
along I-70 as well and continue into Tue as main upper level
trough moves across so will include zn 34 as well.


.SHORT TERM...(This evening through Tuesday)
Issued at 300 PM MST Mon Feb 27 2017

Main concern over next 24 hours will be snowfall potential with
incoming system over mountains and portions of the plains.
Initially this afternoon, the upper level trof is over the Great
Basin with a strong southwest flow aloft. There is also a 140kt
jet that is lifting northward over Western Colorado. Snow showers
are increasing over the mountains this afternoon but webcams
showing snow mainly over the higher terrain and not much happening
on valley floors. Best chance of snow will be early this evening
before decreasing overnight with departing jet and northern
portion of the wave moves off.

Next batch of deeper moisture over Southern California will move
into area on Tuesday with moderate QG ascent even over east
central Colorado by afternoon. With shallow upslope and modest
lapse rates, models continue to show some light snow
accumulations for locations just East and South of Denver and
extending across the Palmer Divide. Will maintain these areas with
the higher chances of snowfall.

.LONG TERM...(Tuesday night through Monday)
Issued at 300 PM MST Mon Feb 27 2017

Snow and strong winds will continue in the mountains Tuesday night
with a push of stronger winds expected after midnight. Gusts of up
to 60 mph should occur down the east slopes of the Front Range
mountains, foothills and along the Cheyenne Ridge. An additional 2
to 4 inches of snow is expected over the high mountains. Over the
plains, decreasing snow showers are expected over areas south and
east of Denver. Up to an additional inch of snow is expected with
northerly winds of 20 to 30 mph decreasing and becoming westerly.

Northwesterly flow aloft will keep cooler temperatures over the
area with light orographic snow over the mountains Wednesday. A
shortwave upper ridge Thursday, followed by westerly zonal flow
Friday, then a larger upper ridge Saturday into Sunday will allow
for several days of warm and dry conditions across the area.
Models diverge on the next system with the Canadian and EC pushing
in the trough on Saturday night into Sunday for snow pushing into
the mountains, with the Canadian wanting to bring precipitation
across the plains Sunday. The GFS is much slower bringing in the
system and drier. Overall the system seems to be wanting to stay
too far north, with not a lot of moisture. For now, will only
allow a chance over the mountains Sunday and keep out any mention
of precip for the plains.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 759 PM MST Mon Feb 27 2017

Fnt is moving towards DIA fm the north which is 4 hours ahead of
schedule and should switch winds to a more nne direction by 04z
and then more ely by 06z. By 12z they will become more sely.




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