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fxus65 kbyz 172146 
afdbyz

Area forecast discussion
National Weather Service Billings Montana
246 PM MST sun Nov 17 2019

Short term...valid for Mon and Tue...

Shortwave was moving across southern Canada, with a plume of
moisture on its south flank. This moisture was showing up as snow
in the mountains and scattered areas of rain in the lower
elevations of the west. Models keep this precipitation mainly over
western and central zones, but energy does drop into southeast
Montana overnight for pop inclusion there. Otherwise, clouds will
be decreasing overnight. Monday looks dry with warmer
temperatures. Highs should be able to reach the mid 50s for most
locations. The east will be slightly cooler in sharper northwest
flow. The next system approaches the west Monday night as energy
pushes out ahead of a trough moving into western Washington.
Timing looks a little slower compared to earlier runs, so backed
off a bit on scattered pops over the west Monday night.

Now to winds: highlights have been verified at Livingston and
around Harlowton with gusts near 60 mph. Ascent with clouds and
areas of rain have kept some of the stronger winds aloft, but as
some subsidence works in late this afternoon, along with strong
700mb winds, feel the best opportunity for the strongest winds
will be late this afternoon and early this evening. Winds were
already starting to pick up some at Big Timber, with gusts in the
mid 50s. Expect a drop off of wind activity late this evening and
overnight as 700mb winds decrease. Will keep wind highlights in
place. Twh

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

By Tuesday, a split trough is progged to move into the region with
the area under the northern branch with a cut off low developing
over California in the southern branch. Rain and snow look to
spread across the area Tuesday night and Wednesday as a cold front
drops south through the region bringing colder temperatures.
Precipitation chances diminish by Wednesday evening as forcing
wanes and high pressure begins to build in from the west. At this
time, precipitation and snow amounts look to be on the lighter
side. Freezing drizzle over eastern areas Wednesday morning still
looks like a possibility and have kept it in the forecast.

Drier and warmer conditions look to prevail over the area Thursday
through the weekend, with high pressure building in over the
northern rockies. There are some indications that a few showers
could impact the mountains and foothills on Sunday. Otherwise,
with high pressure west of the area and Lee side troughing progged
to develop over central Montana, surface pressure gradients will
tighten bringing a period of increased winds to The Gap areas
Friday into Sunday. Have maintained higher winds for the western
foothills. High temperatures are forecast to range from the 40s
and 50s on Tuesday, cooling into the 20s and 30s for Wednesday.
Temperatures will slowly rebound Thursday into the weekend with
highs mainly in the 40s. Low temperatures are forecast in the 20s
most nights, with Wednesday night seeing teens for some areas. Stp

&&

Aviation...

Strong west to southwest surface winds from klvm to k6s0 and up
to khwq will continue through early evening, with gusts of 50 to
55 kts. Winds will decrease overnight. Elsewhere winds will be
weaker, with gusts 15 to 20 kts. Low level wind shear remains possible around
mainly kmls to kshr tonight. Scattered areas of rain and mountain
snow, will provide brief MVFR conditions late this afternoon and
this evening. Mountain obscurations are expected. Twh

&&

Preliminary point temp/pops...

Mon Tue Wed Thu Fri Sat sun
-----------------------------------------------------------
bil 042/058 035/051 029/035 022/040 026/048 028/048 031/046
20/u 14/o 64/S 20/u 00/north 00/u 12/o
lvm 040/056 037/052 027/035 017/041 024/047 026/046 027/044
20/north 26/r 54/S 10/u 00/north 00/north 12/o
hdn 039/058 032/052 026/036 018/040 021/048 023/048 026/047
20/u 13/o 54/o 20/u 00/u 00/u 12/o
mls 040/054 031/049 027/035 019/038 022/044 024/045 027/044
10/u 03/r 53/S 10/u 00/u 00/u 02/r
4bq 041/055 030/052 026/035 018/037 021/046 023/046 026/045
30/u 01/b 33/S 20/u 00/u 00/u 02/r
bhk 038/050 027/045 025/032 017/036 021/042 023/042 025/042
30/u 02/r 43/S 10/u 00/u 00/u 02/r
shr 035/055 029/053 024/034 016/037 016/047 020/047 022/045
40/u 01/b 35/S 40/b 00/u 00/u 12/r

&&

Byz watches/warnings/advisories...
Montana...High Wind Warning in effect until 6 am MST Monday for zones
63-141-172-228.
Wind Advisory in effect until 6 am MST Monday for zones
65-66.
Wyoming...none.

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