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000
FXUS65 KMSO 081136
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
436 AM MST Sat Mar 8 2014

...The Little Bitterroot River is flooding from Hot Springs to
the Flathead River. The Little Bitterroot Road is closed due to
water passing over bridges and the roadway...

...Watch out for icy roads this morning, especially from Superior
to Lookout Pass on I-90...

...Flooding and avalanche concerns will again increase on Sunday
and Monday...

.DISCUSSION...Water on I-90 west of Missoula has turned into ice
and black ice this morning. Conditions from Superior to Lookout
Pass are very slick. Many locations will improve after sunrise but
shaded areas will likely remain icy through mid-morning.

A fair amount of cloud cover remains throughout northwest Montana
and into the Glacier region this morning, so this has inhibited
fog in many locations. Most of the region has conditions near
saturation so even a little clearing of the skies will allow for
fog to develop or maintain through the morning. Locations south of
I90 will see the sun into this afternoon, which should be a
welcome sight. Cloud cover will take back over ahead of the next
weather system by late afternoon.

A plume of moisture is still on tap to bring periods of moderate
to heavy precipitation near the Idaho/Montana border and across
northwest Montana tonight into Sunday. Snow levels will generally
be around 7,000 feet. Precipitation amounts will generally range
between 0.50 to 0.75". A few locations could see close to an 1.00"
or higher especially across the Cabinet & Coeur d`Alene
Mountains, central and eastern Clearwater County, Idaho and across
Glacier National Park through Sunday afternoon. Impacts related to
this event include an increased avalanche danger and an increase
of snow melt with a some increase in small stream levels.
Southerly winds will increase across the Camas Prairie and
Grangeville area late this evening through Sunday morning. Winds
could gust as high as 50 mph by Sunday morning which could cause
some dangerous cross- winds for high profile vehicles. Also strong
gusty westerly winds potentially in excess of 50 mph could pose an
issue on US-2 south and east of Essex to Marias Pass tonight
through Sunday afternoon.

Another weather system will move into the region Sunday night into
Monday. Weather models continue to show snow levels crashing with
a zone of heavy precipitation from Idaho County to southwest
Montana. This system has the potential to bring heavy wet snow to
even valley locations. This system will also bring an elevated
avalanche danger in these areas as well as an increase in small
stream flooding potential. Precipitation amounts will range from
0.30 to over an inch with this system. It`s a little early to
have increased confidence in snow amounts, but higher elevations
could easily see up to a foot of wet snow while lower elevations
see less.

Snow showers will linger on Tuesday under a cool northerly upper
level flow, but high pressure will build in and the region will dry
out by late in the day. General high pressure over the northern
Rockies appears to bring rather benign weather with temperatures
fairly close to normal, breezy afternoons, and a weak weather
system for Thursday.



&&

.AVIATION...Mid-level clouds are decreasing through northwest
Montana early this morning, which has inhibited many locations
from producing fog. There is a light surface pressure gradient
through western Montana resulting in some light wind that has
been keeping fog production down as well. Even with the light wind
and some cloud cover, most of the region has at to near saturated
surface conditions so many areas will have fog and freezing fog
into this morning. Since there are factors going against
widespread dense fog, any fog that does develop should begin to
lift and dissipate after mid-morning. Another than some fog,
conditions will be fairly nice through much of Idaho and western
Montana today with some sunshine early in the day and increasing
high to mid-level clouds late in the day.

The next weather system will arrive tonight with terrain obscurations
and moderate to heavy rain for north central Idaho and portions of
northwest Montana.


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...WINTER WEATHER ADVISORY until 11 AM MST this morning Lower Clark
     Fork Region.

ID...None.
&&

$$

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