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Area forecast discussion 
National Weather Service Great Falls Montana
1025 PM MST Sat Nov 22 2014

Aviation section updated


The surface low and upper level trof that caused widespread high
winds this afternoon is tracking further away through southern
Saskatchewan. The surface pressure gradient has weakened, as has
the Post-frontal subsidence. Observed winds are now all below high
wind criteria. Strong gusty winds will continue through early
Monday, but expected to trend lower. Therefore, have dropped the
High Wind Warning and lowered the forecast wind speeds accordingly.
A subtle shortwave feature is producing snow over central Idaho.
Short term model guidance moves this feature with light snow
showers across south- central and southwest Montana through Monday
morning. Additional snow accumulation will be less than 2 inches.
The Winter Weather Advisory in this area will continue through
Monday morning for snow and blowing snow. Light flurries also
continue over the northern rockies, but dropped the Winter Weather
Advisory here as little, if any, new snow accumulation is
expected. Nutter


updated 0525z.
Surface pressure gradient and winds aloft associated with the
upper-level trof that moved through the region earlier today
continue to steadily decrease tonight, allowing wind gusts to drop
below 25 kts over all but a handful of locations. Expect VFR
conditions with a mix of scattered to overcast mid-level (generally above 5000
ft) over central and southwest Montana tonight. Small area of -rasn
south and west of khvr will persist and may drift toward khvr so
will keep mention of vcsh until Sun morning. A weak trof currently
over western Montana will cross the Continental Divide later tonight,
bringing some scattered -shrasn and ceilings lowering to around
3500-4000 ft at khln/klwt/kbzn starting around 10-12z.


Previous discussion...
/issued 435 PM MST Sat Nov 22 2014/

Tonight through Monday...the cold front has moved through most of
north central and southwest Montana as of 3 PM. Strong gusty west
winds will continue across most of north central Montana through
the evening, so will let the High Wind Warning continue there
through 10 PM. Spotty strong wind gusts are expected across
southwest Montana, but they will likely remain below high wind
criteria. Overall, winds will decrease overnight, but breezy
westerly surface winds will persist into the beginning of next
week. The shortwave trough associated with the cold front is also
moving through the area, and a disturbance in the resulting
northwesterly flow aloft will keep a chance of snow showers across
much of the area overnight. Although additional snowfall in the
mountains will be only a matter of 1 to 3 inches, the fact that
snow showers will likely continue overnight is enough to keep the
Winter Weather Advisory in effect through tonight. A series of
disturbances in the northwest flow will keep at least a chance of
snow showers around through Sunday night, especially in the
mountains. However, am not anticipating enough snowfall to warrant
further winter weather highlights at this time, but the situation
will continue to be monitored. Temperatures in the wake of the
cold front will likely only cool to just below seasonal averages.

Monday night through Saturday...unsettled weather continues into
the long term forecast as northwesterly flow aloft will allow for
some instability to move across the area Monday night and Tuesday.
Models have tended to come into a little better agreement with a
cooler and wetter solution for Wednesday through Friday and have
trended the forecast that way. Some decent snowfall amounts are
expected in the higher terrain at this time but models differ on
the details of how much will fall and where the heaviest snow will
be. It now appears that travel plans could be affected at least
over mountain passes and winter weather highlights might
eventually be needed. Blank/suk


Preliminary point temps/pops...
gtf 50 27 39 25 / 20 10 10 20
ctb 43 23 36 24 / 20 20 10 10
hln 48 28 39 27 / 50 20 20 30
bzn 47 18 34 18 / 90 30 20 40
wey 35 11 25 11 / 100 50 40 60
dln 43 20 32 16 / 90 30 20 30
hvr 51 26 35 22 / 20 40 20 30
lwt 50 26 36 24 / 20 30 30 30


Tfx watches/warnings/advisories...
Winter Weather Advisory until 5 am MST Sunday for US 89 over
Kings Hill Pass.

Winter Weather Advisory until 5 am MST Sunday Beaverhead...




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