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Area forecast discussion 
National Weather Service Billings Montana
305 am MST Friday Nov 27 2015

Short term...valid for today and Sat...

Stubborn upper low continues to linger over the Great Basin in
the short term periods. We are generally north of any dynamics
for today so a dry forecast continues to look on target. A little
concerned for high temperatures today as many locations will be
starting off quite cold /below zero in some cases/ and there is
not an obvious reason to be much warmer than yesterday. I shaved a
few degrees off average guidance to account for this cold start
and lack of boundary layer mixing. We may see some increase in
high clouds from the south tonight which prevents the Mercury
from dropping quite as hard as Thursday nights temperatures...but this
may only be true for southern half of our forecast area.

Saturday...models tend to agree that the upper low will meander
north/northeast slightly. Proggs suggest this will eventually
wrap some moisture into the region from the south by Saturday
afternoon and into the night. Isentropic lift associated with this
pattern will gradually shift north as well and should provide
enough ascent into southern Montana and northern Wyoming for
measurable snowfall. The northern extent of this precipitation is
questionable as Standard deviations for the ensembles remain
rather high for short term periods. So our probability of precipitation are relatively
low...but we could certainly see a couple of inches in the big
horns region and maybe in southern sections of Powder River
County. North of these areas I would not be surprised to see some
flurries including the Billings vicinity Saturday night...but the
chance of measurable snowfall at this time looks pretty low. Bt

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

Not many changes required to the long term package. A slow warm
up trend is still expected through next Friday after some early
week snow in southeast Montana.

The stubborn upper level low will still be in place over Utah
Sunday afternoon. Weak piece of energy will feed into the bottom
of the trough over the weekend and this will help eject this upper
level low eastwards by Tuesday afternoon. Ahead of this ejection
weak ripples of energy and some enhanced divergence aloft will
help initiate an isolated chance for snow showers across the area
Sunday...though the best chances appear to be east and south of
Miles City...Hardin...and Sheridan. Model quantitative precipitation forecast placement is highly
dependent on the eventual path of the upperlow so slight chance
probability of precipitation are broadbrushed across the central and eastern zones as
ensemble guidance is in good agreement of at least some quantitative precipitation forecast in
these regions. As surface cyclogenesis picks up across northern
Colorado and western Kansas early Monday...we could see intensity
of precipitation pick up through Monday afternoon. With this in
mind I have raised probability of precipitation slightly over Miles City and Ekalaka for
that period. Snow chances should begin to end late Monday as the
upper level disturbance begins to pull away.

Upper low kicks out Tuesday afternoon and in its wake expecting
seasonable conditions with high temperatures in the 40s through
Friday. Morning lows could be chilly across extreme southeast
Montana on Wednesday morning..especially in locations that see
good snowfall amounts. Dobbs



VFR conditions and light winds will prevail across the region
through the taf period. Dobbs


Preliminary point temp/pops...

Today Sat sun Monday Tuesday Wednesday Thursday
bil 023 006/030 013/031 016/035 021/040 024/042 027/044
0/u 01/b 21/b 11/b 10/b 00/u 00/b
lvm 023 011/032 012/032 014/035 020/037 022/040 025/042
0/u 01/b 21/b 11/b 00/b 00/u 01/b
hdn 027 000/030 011/031 014/035 018/041 018/043 020/044
0/u 01/b 21/east 22/j 10/b 00/u 00/b
mls 026 901/030 010/029 015/033 017/039 018/043 020/042
0/u 00/b 11/east 33/j 21/b 00/u 00/b
4bq 026 005/029 011/028 014/031 018/038 017/041 018/041
0/u 02/S 22/j 33/j 31/b 00/u 00/u
bhk 026 004/031 011/030 016/032 018/036 017/042 020/042
0/u 00/u 11/east 33/j 31/b 10/u 00/u
shr 023 004/028 011/029 010/032 016/040 014/043 019/043
0/u 02/S 32/j 23/j 21/b 00/u 00/b


Byz watches/warnings/advisories...



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