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Area forecast discussion...updated 
National Weather Service Billings Montana
925 am MST Monday Nov 30 2015


A quiet day is in store and the previous forecast has this
covered well. Stubborn upper low currently over Nebraska and Iowa
will continue to rotate clouds westward across southeast Montana
today. Clouds are expected to be of the middle level variety so no
precipitation is expected so snow shower chances were removed for this
area. Some clouds will linger over the mountains and foothills
areas throughout the day. Web cams not showing much happening at
all so snow shower chances were lowered to just a slight chance
for this morning. The other adjustment with this update was to
tweak sky cover with most areas seeing a partly to mostly sunny
day. Updated forecast has been sent. Hooley


Short term...valid for today and Tuesday...

Pattern synopsis...the upper low thats been over the Great Basin
for the past week is sitting over central Wyoming tonight...and
will be slowly wobbling its way east to Iowa by midday Tuesday. As
it meanders east we will be affected by weak spokes of energy
rotating from east to west across our forecast area.

One of these spokes of energy was tracking over southeast Montana
overnight. We have seen some decent radar echoes in our Red Lodge
and beartooth foothill zones...but little of this has translated
into much measurable precipitation as noted on area web cams and
observations. Cross sections provide a clue as to why...with
upslope and saturation only at levels above about 8500 feet...and
downslope winds prevailing in the lower levels. So northern faces
of higher elevations are looking at a few inches but we do not
expect much snowfall accumulation in the foothills or nearby lower

The next spoke rotating through our forecast area will begin to
affect our eastern border counties around midday...and into the
foothills again by late afternoon/evening. Cross sections indicate
the best moisture is even higher than its predecessor. So we may
not see much more than virga with this afternoon spoke. Then the
last measure of energy to wrap into our region is Tuesday.
Moisture levels and upslope flow may be able to generate some
light snowfall over our far eastern border will
continue to carry some low probability of precipitation late Monday night through Tuesday
morning along eastern border.

Temperatures will continue to gradually warm as the upper low
pulls away. Bt

Long term...valid for Wednesday...Thu...Fri...Sat...sun...

No major changes to the long term forecast this update. Long term
period will feature ridging and accelerated flow aloft thanks to
several Pacific systems rounding the western Continental U.S. Ridge. This
type of flow can provide good downslope conditions and warmer
temperatures. Maximum temperatures will start out in the middle 40s on
Wednesday and warm into the upper 40s by the weekend. 50s are
certainly possible by Saturday. Precipitation chances should
stay mostly west of the forecast area through the long term but
high elevation snow is possible Friday and early Saturday.

While temperatures will be cover and periods of
wind could lessen the perceived warmth when the wind chill is
factored in...putting a damper on the weekend warmth. For now
winds are below advisory levels in our favored gap flow locations
such as Livingston and Nye but will monitor in case we need to
elevate winds in future updates. Dobbs



VFR conditions are expected through the taf period. Southwest
winds are expected to turn southwest in klvm late this
evening...and increase overnight...with gusts to approaching 30
knots by Tuesday morning. Otherwise no aviation hazards are
expected across the region. Gilstad


Preliminary point temp/pops...

Today Tuesday Wednesday Thursday Friday Sat sun
bil 032 018/039 021/043 024/045 030/048 028/046 026/047
1/b 00/north 00/u 00/b 01/b 11/u 00/b
lvm 031 021/035 021/040 024/047 031/047 025/042 026/045
1/b 00/north 00/north 00/north 01/north 11/north 00/north
hdn 033 011/038 012/040 016/044 020/047 024/044 019/044
1/b 00/b 00/u 00/u 00/b 11/u 00/b
mls 026 009/033 013/038 018/042 021/048 025/042 023/044
0/b 00/b 00/u 00/u 00/b 11/b 00/b
4bq 029 014/035 013/042 019/044 027/050 027/045 023/046
0/b 00/b 00/u 00/u 00/b 11/u 10/u
bhk 025 011/031 014/041 018/044 023/047 024/043 021/046
0/b 11/b 00/u 00/u 00/b 11/b 00/u
shr 030 014/038 015/042 017/043 023/047 022/043 020/046
1/b 00/b 00/u 00/u 00/b 11/u 10/u


Byz watches/warnings/advisories...



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