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Area forecast discussion 
National Weather Service Great Falls Montana
423 am MST Monday Nov 30 2015

..update to aviation...


Today through upper ridge over southwest Canada
and a closed low currently over Wyoming will continue to influence
Montana weather. The upper low continues to move slowly eastward
into the northern plains and will keep Montana beneath a dry
northeast flow aloft. Inversions in southwest valleys will keep
areas of fog in place this morning. Have issued a freezing fog
advisory for the Helena valley where visibilities have been near
or below one quarter of a mile for much of this morning. In
addition, am still expecting a slight chance for a few light snow
showers near Yellowstone Park. Westerly flow aloft returns for
Tuesday and Wednesday as the low moves eastward and combines with
falling pressure in Alberta for increasingly breezy conditions
along the east slopes of The Rockies. Temperatures remain quite
cool beneath the inversion in southwest valleys but increasing
temperatures are likely across north central by Wednesday as
breezy conditions bring warmer air to the state. Mpj

Wednesday night through Monday...
models continue to remain in decent agreement that the ridge of high
pressure that has been residing over the area for the last few days
will finally exit the region to the east as the next trough moves
inland over the Pacific coast by Friday morning. The next weather
system does not look to produce any significant moisture over the
lower elevations at this time... but it does look like some windy
conditions will be possible by Friday evening and overnight into
Saturday as the pressure gradient increases ahead of the energy
moving across Montana. Throughout the time period temperatures look
to stay near seasonal average with some additional warming on Friday
as the wind does produce some downslope warming. While some mountain
precipitation will be possible throughout this time frame no
significant precipitation is anticipated at the lower elevations
through next weekend. Suk


Aviation...updated 1123z.

High pressure aloft will keep the airmass dry with mostly clear
skies for widespread VFR conditions. At lower levels, moisture is
available for areas of fog with LIFR/vlifr conditions in some
valleys and near rivers, including vicinity khln this morning and late
tonight. Mpj


Preliminary point temps/pops...
gtf 28 13 33 24 / 0 0 0 0
ctb 39 14 39 23 / 0 0 0 0
hln 18 1 22 17 / 0 0 0 0
bzn 19 -7 22 9 / 0 0 0 0
wey 21 -10 20 -2 / 20 10 0 0
dln 18 -6 21 10 / 0 0 0 0
hvr 26 4 31 18 / 0 0 0 0
lwt 33 13 38 23 / 0 0 0 0


Tfx watches/warnings/advisories...
freezing fog advisory until noon MST today for mtz014.




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