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Area forecast discussion...updated 
National Weather Service Billings Montana
1004 am MST Sat Nov 28 2015


Minor adjustments to the going forecast. Latest met came in with
temperatures significantly colder than the mav for Billings...due
to persistent drainage wind out of the Bighorn valley. The mav
also has this wind direction so split the difference and lowered
temperatures into the middle 20 for highs. For the rest of the area
temperatures should be about 5 degrees warmer than yesterday with
higher hills even warmer than that. Already in the low to middle 20s
in the western foothills. Energy wrapping around the stagnant
upper low to the southwest is pushing a band of light snow
northward through Wyoming. Models in pretty good agreement with
this band reaching areas along the Montana/Wyoming border before washing
out. Bumped up precipitation chances along the border and Sheridan
County to account for this snowfall. Still expect an inch or less
accumulation from this activity...but travelers could experience
some snow covered roadways and reduced visibility at times. Light
snow chances will continue over southeast Montana and northern
Wyoming tonight. Chambers


Short term...valid for today and sun...

Upper low continues slowly rotating over the Great Basin and will
gradually shift into the central rockies in the short term. Models
generally show a similar scenario with an area of q vector forcing
rotating around the upper low into our forecast area today...and
remaining entrenched through the weekend. Despite
this...ageostrophic circulations are not impressive on cross
sections and vertical column never becomes completely saturated in
the lower levels. So I expect to see this band of
precipitation rotate into our region and produce a
continuous...albeit light snow late today through the rest of the
weekend. Best chance of measurable precipitation remains over the
south/southeast zones...and especially into the higher elevations
of the big horns where there will also be some upslope flow out of
the east and northeast. I expect maybe occasional flurries
elsewhere...including Billings. Over time we may accumulate a few
inches in the big horns with around an inch in nearby foothills
and over the southeast sections of our forecast area.

Temperatures will very gradually warm through Sunday...but
otherwise remain below normal. Bt

Long term...valid for Monday...Tue...Wed...Thu...Fri...

Significant changes were not needed for the long term forecast.
Somewhat unsettled weather affects eastern Montana Monday
afternoon and then a warm up occurs through the work week.

Upper level low will depart the region to the east through the
afternoon on Monday. Snow...if southeast Montana will
quickly decay and move east by late Monday. Not expecting
significant accumulations in Carter and Powder River counties...though
there is still some model uncertainty. The trend has been towards
lower amounts and further southeastward so felt confident
lowering probability of precipitation.

On Tuesday a ridge axis moves into the western Continental U.S. And then the
warm up will begin. The warmup will be fairly slow with maximum
temperatures starting out in the middle 30s Monday warming up to the
middle 40s by Friday. Nighttime lows will start out cool in the teens
but will warm up to the upper 20s by next Saturday morning. Enjoy
the warmer weather! Dobbs



VFR conditions will prevail across most of the region today...but
with increasing clouds from south to north. Southwesterly winds around
15 kts are expected to persist around kbil today...while most
other locations will see light winds. Light snow will move into
the kshr area by middle afternoon...and will spread north and east
into extreme southern Montana by late this evening. MVFR/IFR
conditions are possible with the snow. Flurries to light snow is
possible as far north as kbil and kmls overnight tonight.
Mountain obscurations are expected to increase along the
beartooths and Big Horn throughout the day. Gilstad


Preliminary point temp/pops...

Today sun Monday Tuesday Wednesday Thursday Friday
bil 026 010/030 016/032 020/037 024/041 026/041 027/044
0/u 12/S 11/east 10/b 00/u 00/b 01/b
lvm 030 009/032 014/033 017/033 021/036 023/039 027/042
1/u 00/b 11/b 00/u 00/u 01/b 12/west
hdn 028 007/029 010/031 012/037 016/040 019/043 018/043
1/b 22/S 21/east 10/b 00/u 00/b 01/b
mls 027 004/026 008/028 012/035 016/040 020/041 020/042
0/u 23/S 21/east 11/b 00/u 00/b 01/b
4bq 028 014/028 010/028 013/035 017/040 019/042 022/044
3/S 33/S 22/j 21/b 00/u 00/u 01/b
bhk 030 009/027 010/028 014/033 016/039 020/041 021/041
0/u 33/S 22/j 21/b 10/u 00/u 01/b
shr 027 012/028 009/029 012/038 013/041 017/043 021/043
5/S 43/S 21/east 11/b 00/u 00/u 01/b


Byz watches/warnings/advisories...



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