070 
FXUS65 KMSO 091044
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
344 AM MST Sun Dec 9 2012

.DISCUSSION...Snow showers that developed last evening are still
bringing light snow to western Montana early this morning.
Accumulations have been light in most cases, although, there has
been an area of snow that stalled south of Bigfork near Woods Bay,
so a few inches of snow likely fell. Slick road conditions due to
this snow are likely on that portion of highway 35 near Woods Bay.
Light snow showers will continue to weaken through this morning.

There will only be a brief break between systems since the next one
is quickly approaching. Light snow will arrive by this afternoon
in northwest Montana and this evening for north central Idaho and
west central Montana. Initially there will be plenty of cold air
for snow production to be efficient with accumulations possible
through this evening. Model guidance agree that north central
Idaho will fall in the favorable portion of this system to receive
majority of the snow accumulations overnight tonight. Moisture
becomes more limited at mid levels, so there is still a slight
chance for freezing rain to develop briefly Monday morning.
Moisture will again increase through the day Monday so snow
chances will remain into Tuesday.

Wednesday through Friday...A somewhat progressive flow with
several weak to moderate disturbances moving through a general
northwest flow under a long wave trough across the Northwestern U.S.
Though the overall synoptic pattern does not look overly strong
the subtle features will have to be monitored closely. These
northwest flow patterns with weak to moderate short waves can play
havoc in the valleys of Western Montana. It is much too early to
have any confidence with timing of the potential subtle features
so stay tuned to the latest forecasts and discussions by midweek.

Saturday and Sunday...Models continue to show a potential for a
couple of strong systems developing accompanied by a strong jet
stream aloft. However confidence is still low for timing, location
and strength of these potential systems. If these storms come to
fruition then the mountains of central Idaho and western Montana
could see some significant snowfall.


&&

.AVIATION...Snow showers continue to bring lowered ceilings and
visibilities to portions of western Montana, but these showers are
beginning to weaken. Locations that have had limited cloud cover
overnight have produced patchy fog that will last into this
morning. There does not appear to be any considerable time-frame
without cloud cover today. Lower cloud cover being formed by
upslope flow will continue over much of the terrain of Idaho and
western Montana and cloud cover with the next system is just off
to the west. There will also only be a short period of time later
this morning with limited precipitation since model guidance agree
that light snow will begin this afternoon. Widespread light snow
should be expected this evening and tonight with low ceilings and
visibilities common through Monday morning.






&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$

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