Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 021636

Area Forecast Discussion
National Weather Service Billings MT
936 AM MST Fri Dec 2 2016


Quick update this morning to clean up pops across the region.
Western zones are clearing pretty quickly...while eastern zones
may still be seeing some isolated light snow. Chose to clear
western plains of pops...based on clearing. Kept slight pops in
eastern plains through the morning. Also pared back mountain pops
slightly. Otherwise... the going short term forecast appears on
track...with strong gusty winds expected across western
zones...especially areas impacted by gap Livingston
and Nye. AAG


.SHORT TERM...valid for Tdy and Sat...

Weak upper trough was pushing through southern Montana early this
morning and was producing some light snow showers over mainly
central zones. Activity was pretty weak and will continue to shift
southeast with the trough and weaken through the morning. Will
keep the afternoon dry as the trough sinks into Wyoming. Several
waves of energy will move across the area in northwest flow
through Saturday night, but activity will be weak and limited in
moisture availability, so will keep PoPs low. Low level downslope
flow will continue and provide seasonal to slightly above seasonal

Main weather story for the short term will be winds near
Livingston and Nye. Surface pressure gradient progged to tighten
significantly tonight through Saturday morning. This will allow
winds to hit advisory criteria, mainly overnight tonight and
Saturday morning, but possibly as early as this evening. The
gradient relaxes Saturday afternoon before tightening again
Saturday night for another round of strong winds. Will keep
advisory in place and maintain the wording for a brief lull in
activity Saturday afternoon. TWH

.LONG TERM...valid for Sun...Mon...Tue...Wed...Thu...

Gap areas winds around 50 mph taper off as a strong upper low
approaches the region from the northwest on Sunday afternoon. Snow
moves into the Absarokas and Beartooths on Sunday afternoon before
spreading over the Plains on Sunday night. Models have varied over
the last several days with the exact handling of the precip
associated with this system. GFS has come more in line with the
Euro, with a surface low progged over the Dakotas, which is
further south than yesterday`s run. The Euro is still persistent
with post frontal snow on Monday although the latest run is a bit
quicker to clear things out. Meanwhile, the GFS has trended a bit
wetter than previous runs with more precip being generated ahead
of the approaching arctic air mass. Consensus for now is
accumulations generally in the 2 to 4 inch range for the foothills
and Plains. However, given the model variation still a lot of
uncertainty in the exact evolution of the snowfall Sunday-Monday.

Continued agreement that we will see below normal temperatures as
we head into the work week. Temperatures will struggle to get out
of the single digits in most places Tuesday morning through
Thursday morning due to overcast skies, snow covered ground, and
an intruding arctic air mass. The coldest day still appears to be
Wednesday morning with lows 5 to 10 degrees below zero in most
areas. Temps begin to trend back toward normal conditions by
Friday just in time for the next strong low pressure system to
slide in by the weekend. Walsh



IFR/LIFR conditions this morning will improve to MVFR conditions
around 19z over far eastern zones including KBHK. MVFR/VFR
ceilings over the rest of the area this morning will scatter out
by 19z leaving VFR conditions this afternoon into this evening.
Southwest winds gusting to 40kts will develop this evening over
western foothills zones including KLVM, with strong wind gusts
expected there through the weekend. Chambers


    Tdy Sat     Sun     Mon     Tue     Wed     Thu
BIL 038 026/043 028/044 023/026 004/007 905/004 002/019
    1/B 22/J    23/W    54/J    31/E    11/B    11/B
LVM 036 033/040 031/043 022/022 901/010 907/012 001/022
    1/N 33/W    45/W    53/J    31/B    11/B    12/J
HDN 035 022/043 027/046 024/027 004/009 905/003 000/018
    1/B 13/W    22/W    44/J    32/J    11/B    11/B
MLS 035 022/041 025/043 022/025 002/007 907/002 905/011
    2/J 03/W    12/W    34/J    32/J    11/B    12/J
4BQ 031 017/040 023/042 022/025 000/008 908/003 907/014
    2/J 02/W    11/E    24/J    32/J    21/B    11/B
BHK 031 016/038 022/040 020/023 000/006 909/001 908/009
    2/J 02/W    11/B    25/J    42/J    11/B    11/B
SHR 037 015/041 020/044 023/026 002/012 907/008 903/020
    2/J 02/W    11/E    23/J    32/J    11/B    11/B


MT...Wind Advisory in effect from 6 PM this evening to 6 PM MST
      Sunday FOR ZONES 65-66.


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