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Area forecast discussion 
National Weather Service Billings Montana
231 PM MST Wednesday Dec 17 2014

Short term...valid for Thursday and Friday...

Weak upper low pressure system will move across northern Montana
tonight and will bring areas of light snow this evening across our
northeast zones. Snow is expected to be very light with no
accumulations. As the low moves to our east tonight...some
clearing is expected across our western and central zones. This
will allow for cooler overnight low temperatures with teens to
lower 20s. Hrrr is indicating fog to redevelop over southern
Powder River and Carter counties tonight as low level moisture
remains pooled over these areas. Did included patchy fog for
portions of southeast Montana tonight. Weak short wave to move
through Thursday which which will bring scattered snow showers to
our Southwest Mountains. Dry weather and slowly warming
temperatures will continue into Friday as short wave ridging moves
in over the region. High temperatures will be in the upper 30s to
lower 40s both Thursday and Friday. Richmond

Long term...valid for Sat...sun...Mon...Tue...Wed...

Guidance continues to be in good agreement into early next week.
While the finer details may differ..the overall unsettled pattern
in the extended continues. After the ridging Friday...a weak
shortwave will cross the state...bring another chance for light
precipitation to the mountains. Upper level flow begins to increase
Saturday night as a Pacific jet starts moving into the state. Lee
side troughing develops...with a surface low developing over
southern Alberta. In response...the pressure gradient tightens
over southern Montana...resulting in stronger winds developing
first in The Gap areas...then spreading out to around Billings.
Mex MOS for Livingston has winds increasing into 30 miles per hour to near
40 miles per hour range Sunday afternoon. Still keeping grids sub advisory
given this is still four days out...but if current trends
hold...looking at another wind event during the day Sunday.

As the low tracks out of Canada into the northern plains
Monday...a cold front moves through the area. With ample moisture
still bring transported into the area...probability of precipitation continue Monday into
Tuesday. Temperatures will remain relatively much of the
central zones still look to get rain. Farther east wards Miles
City and Baker...where temperatures are a bit cooler...may see
some freezing rain. Winds will also be more north
not as much of an up slope flow event. Things begin to tapper
off...with temperatures cooling back into the 30s for highs.

Looking ahead to Christmas evening and Christmas...another low
develops and tracks across the area a shot at
more precipitation. With the system...the air mass in place will be
colder...with 850mb temperatures below freezing. The the GFS and
European model (ecmwf) are suggesting a shot at a white Christmas...will continue
to watch this. Reimer &&


Conditions have improved this afternoon...generally MVFR to VFR.
Expect flight conditions remain VFR/MVFR overnight and into
tomorrow. Some patch fog will be possible south of Miles
City...but will likely not impact any terminals. With some middle level
clouds...some mountain obscuration will continue to be possible.

Preliminary point temp/pops...

Thursday Friday Sat sun Monday Tuesday Wednesday
bil 023/038 023/038 027/041 027/046 033/045 026/038 022/033
00/b 00/b 11/b 13/west 32/west 21/north 23/j
lvm 022/042 024/040 027/043 028/046 035/045 022/039 023/035
01/north 11/north 21/b 24/west 43/west 21/north 33/j
hdn 013/037 015/037 020/040 021/044 029/043 021/037 020/034
10/b 00/b 01/b 13/west 33/west 21/b 22/j
mls 017/038 019/037 021/040 022/042 029/040 025/036 020/031
20/b 00/b 11/b 13/west 22/west 11/b 11/east
4bq 015/041 017/040 019/041 022/044 030/042 024/037 019/033
20/b 00/b 11/b 12/west 23/west 21/b 22/j
bhk 015/036 019/037 019/040 021/042 026/037 021/033 017/027
20/b 10/b 01/b 02/west 22/west 11/north 11/b
shr 015/041 015/038 020/040 019/043 030/042 022/037 019/033
10/b 10/b 11/b 13/west 34/west 32/j 22/j


Byz watches/warnings/advisories...



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