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fxus65 ktfx 181423 

Area forecast discussion
National Weather Service Great Falls Montana
823 am MDT Wed Sep 18 2019


Fair weather prevails this morning. Clouds will gradually increase
from the west today. Overall forecast represents the situation
well, but still sent an update to freshen with respect to current


a southwesterly flow aloft will reside over the region today. As a
result, expect increasing clouds and slightly warmer temperatures
this afternoon. There will be a chance for a rain shower or
isolated thunderstorm tonight and into Thursday as an upper level
disturbance moves through the region. The chance for rain will
continue into Friday over central and southwest Mt, along with
slightly cooler temperatures. Snow will be possible in the
mountains of southwest Mt, mostly above 8000 feet.


updated 520 am MDT Wed Sep 18 2019 (12z tafs)

VFR conditions should prevail over the region into this afternoon,
with the small exception for some patchy morning fog, mostly in the
West Yellowstone area. Expect showers/lowering ceilings to move into
the western portions of the region by late afternoon and into this
evening, with showers continuing into Thursday. Some near MVFR
conditions are possible by evening, mainly west of a line from Havre
to Stanford. Some mountains/passes could start to become obscured by
this evening. Brusda


Previous discussion...
/issued 520 am MDT Wed Sep 18 2019/
today through Friday...a southwesterly flow aloft has developed
over the region. Expect increasing clouds over the region today,
with a chance for a shower by late afternoon in the Glacier park
region. Showers/isolated thunderstorms will move from south to
north through the region tonight and into Friday as an upper level
trof moves through the region. Afternoon temperatures will be a
touch warmer today, but then cool off a few degrees for Thu/Fri.
The chances for precipitation look to be the highest on
Friday/Friday evening over central/southwest Montana. The air mass will
be cold enough that some accumulating snow will be possible over
the mountains of southwest Mt, mostly above 8000 feet, but snow
could mix in as low as about 6500 feet or so. Thus impacts from
snowfall at this time look low.

Saturday through Sunday...a northwesterly flow aloft will reside
over the region on Saturday, allowing for the air mass to be a bit
unstable. Thus a few passing showers will be possible on Saturday.
An upper level ridge starts to rebuild over the region on Sunday,
allowing for dry/warmer conditions to develop.

Monday through Wednesday...overall an upper level disturbance
will slide to our south on Sunday night, resulting in a westerly
flow aloft developing over the region. Generally near normal
temperatures are expected for the first half of next week, with
just low chances for a passing shower. Overall the nbm is on track
during this period with little changes made. Brusda


Preliminary point temps/pops...
gtf 71 46 61 42 / 0 60 40 40
ctb 64 42 60 40 / 40 80 20 10
hln 71 45 61 41 / 10 50 60 70
bzn 73 41 63 40 / 0 0 50 80
wey 65 30 59 30 / 0 0 40 60
dln 67 41 56 37 / 0 80 70 70
hvr 74 46 68 43 / 0 30 30 20
lwt 70 42 63 41 / 0 0 20 40


Tfx watches/warnings/advisories...

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