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Area forecast discussion 
National Weather Service Great Falls Montana
417 am MST Sat Feb 28 2015

Discussion...

Today through Monday...the overall weather pattern changes little
today with an upper level trough extending from central Canada
southwestward into the SW US while at the surface, a cold airmass
remains in place over much of Montana. Upper level low located in the
SW extension of the large scale trough will continue to sink south
through the Great Basin today, allowing drier air in the mid to
upper levels to spread south into the region. This should bring an
end to most of the snow flurry/light snow shower activity by late
this afternoon with skies partially clearing from north to south.
The airmass continues to dry Sunday and Sunday night with some
warming as well as the cold airmass at the surface shifts east
into the northern plains states. Shortwave and upper level jet
energy currently moving over the top of a sharp upper level ridge
located around 140w dives south through western Canada Sunday
night, causing the downstream upper level trough to amplify/deepen
Monday. A strong Arctic cold front will surge south into north-central
Montana Monday afternoon with falling temperatures and increasing north
winds as surface pressure rises behind the frontal passage. Snow
will accompany and follow the front spreading south through
north-central and central Montana by late Monday afternoon. Hoenisch

Monday night through Saturday...a low pressure trof will move across
central Montana Monday night and the associated cold front, already
into the central zones, will move through the southwest zones during
the evening. Widespread snow will continue through the night but
begin to taper from the north towards morning. The trof will be east
of the zones Tuesday night, the airmass will dry and some clearing
skies are expected. The surface high will be over the zones and very
cold overnight lows are expected...negative numbers across the
region with some negative teens in southwest Montana. Winds will be
strong enough to create dangerous wind chills in some locations.
High pressure will continue over the West Coast Wednesday through
Saturday. This will generally put central Montana underneath
northwest flow aloft. Several disturbances will move through this
flow. The first of these on Wednesday will help deepen the surface
trof along the Lee of The Rockies. This will cause strong winds
across the slopes of The Rockies by late Wednesday. Another
disturbance aloft will strengthen winds across The Rockies again
Thursday night through Friday. This latter disturbance will also
bring a chance of snow across The Rockies into central and southwest
Montana Friday and Friday night. Zelzer

&&

Aviation...
updated 1116z.
The upper level low pressure trof over central Montana will move
east of the region by this afternoon. Moisture and lower cigs will
move east and most areas will see VFR conditions by morning. Ample
low-level moisture will remain, however, and areas of MVFR/IFR will
last into mid-morning. Especially near kctb, khvr, and klwt.

&&

Preliminary point temps/pops...
gtf 20 3 34 14 / 20 20 0 0
ctb 20 2 32 15 / 0 10 10 0
hln 25 4 34 14 / 20 10 0 0
bzn 24 0 31 9 / 30 10 0 0
wey 28 -10 32 4 / 30 10 0 0
dln 25 2 33 9 / 30 10 0 0
hvr 23 2 30 12 / 10 20 0 0
lwt 19 2 31 14 / 30 20 10 0

&&

Tfx watches/warnings/advisories...
none.
&&

$$

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