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000 
FXUS65 KTFX 231153
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
453 AM MST Tue Jan 23 2018

...UPDATED AVIATION...

.SYNOPSIS...

Lingering mountain snow will diminish this morning...with mainly
dry conditions then expected across the area. Temperatures will be
near seasonal normals...with highs generally in the 30s. Some
breezy winds are also possible today...especially across northern
and central portions. Mainly dry conditions will again be found for
Wednesday...with gustier winds and warmer temperatures also 
expected. A cold front will then return a chance for snow on 
Thursday...mainly across central and southern portions.

&&

.DISCUSSION...

Today through Thursday...Flat ridging will diminish any lingering
mountain snow this morning...and leave us with mainly dry and 
seasonal conditions for today. Clearing skies could also cool off 
some southwestern valley locations just enough to see patchy 
freezing fog this morning. Impacts will be isolated and brief. 
Afternoon breezes may then pick up for the usual areas of 
northern and central portions today. Ridging stays in place for 
tonight...continuing the mainly dry conditions. Lingering breezes 
will also keep temperatures near seasonal to slightly above normal
readings. The mentioned ridge then pushes to our east on 
Wednesday bringing us southwest flow ahead of the next potential 
weather maker. Moisture in this flow could bring some mountain 
snow...especially along the Rocky Mountain Front. A strong 
gradient also begins to develop ahead of an approaching cold 
front...bringing the potential for gustier winds on Wednesday. 
Gusts look to be below High Wind criteria at this point...although
will be worth watching in the coming days. Temperatures will also
warm up in the down sloping flow...with some highs returning into
the 40s for the northern and central portions...and mid to upper 
30s across the southwest. Thursday then sees the passage of this 
weak pacific cold front. Right now the best chances for snow will
come across the Rocky Mountain Front and southwestern 
portions...with some scattered activity across central portions. 
Snow accumulations at this point look to be light...with perhaps 1
to 4 inches possible across the heavier hit areas of sw MT. 
Temperatures will be slightly cooler on Thursday...although still 
near to above normal. Anglin

Thursday Night through Tuesday...Cold front exits the region
Thursday night...ending the initial round of snow. Flat ridging
then leaves us in a zonal moist westerly flow for Friday. This
could bring scattered areas of light snow showers and lingering 
mountain snow. A pattern of brief ridging followed by moist 
westerly flow then looks to be the story of the weekend. A brief 
ridge moves through Saturday morning before moist westerly flow 
moves through the rest of Saturday. This combined with a weak warm
front boundary could bring more scattered snow showers and 
mountain snow on Saturday...with a similar pattern also expected 
for Sunday. A mainly dry and breezy pattern looks to be possible 
for Monday. Models are then indicating a larger wave and stronger 
cold front may then push across the region sometime early next 
week. The exact timing is still in disagreement...with some models
indicating impacts could be seen as early as Tuesday. If that is 
the case...this quick hitting system could bring chances for 
widespread snow and colder conditions. Temperatures Friday through
Saturday look to be near seasonal normals...with a slight warm up
on Sunday and Monday. After that models diverge...although it 
does appear perhaps a cool down is in store if the mentioned 
disturbance moves through. Anglin 

&&

.AVIATION...
Updated 1200Z.

Overall VFR conditions expected through the forecast period.
Patchy fog is possible across the southwestern valleys this
morning...although impacts look to be isolated and confidence was
to low to include in TAFs at this point. Lingering mid level
clouds could also briefly bring MVFR ceilings this morning to
southwestern sites. The rest of the day will see VFR
conditions...partly cloudy skies...and some breezy winds at times
to most sites. Mainly dry conditions are also expected to all
sites today...with only a few lingering mountain snow showers
possible this morning. Anglin

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  38  29  46  32 /  10  10   0   0 
CTB  35  24  41  26 /  10  10  10  10 
HLN  36  16  36  20 /  10  10   0  10 
BZN  32  15  37  20 /  10  10   0  10 
WEY  23  10  29  15 /  20  30  10  10 
DLN  31  18  38  24 /  10  10   0  10 
HVR  31  17  35  21 /   0  10  10  10 
LWT  34  25  42  26 /  10  10   0   0 

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.

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