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Area forecast discussion 
National Weather Service Billings Montana
822 PM MST Friday Mar 6 2015

Update...
winds have died down quite a bit since sunset but remain a little
gusty along the foothills and over the ridges. Weak shortwave in
northwest flow aloft is dropping into the Dakotas. There are some echoes
on the Bowman radar but ceilings are at least 7-8kft above ground level...so might be
a glancing sprinkle at Baker but thats about it. Behind this
energy are 1 mb/hour pressure rises in NE Montana. So a period of veered
winds and modest cold advection in store for our east half
tonight. Pressure rises will move quickly east later tonight with
Lee side pressure falls once again associated with next shortwave
in northern Alberta. This wave will bring a better chance of light
shower activity tomorrow afternoon and evening.

Have made a few minor tweaks to winds...sky and temperatures tonight.
Have also raised highs a bit tomorrow in our west with prefrontal
conditions...and a frontal passage expected not until late in the day. Could
see near 60f again on Saturday.

Jkl

&&

Short term...valid for Sat and sun...

Strong mixing today has caused a breezy day across most of the
forecast area. Surface pressure falls over the Dakotas indicate a
shifting east of the surface trough over central Montana and a
weakening surface pressure gradient the rest of the afternoon and
this evening. This will allow winds to decrease early this
evening.

Northwest flow will be over the forecast area this weekend. A
weak shortwave will drop down in the flow aloft Saturday afternoon
and evening. There will be some qc forcing and weak frontogenesis
with the wave that swings across central and eastern zones. The
deepest moisture will slide over the east and this is where the
best chance of precipitation will reside. A weak cold front backs
into central zones Saturday evening...so will keep low probability of precipitation for
central zones...although the forcing will be waning at that time.
Mixing will not be as deep Saturday...so expect a slightly cooler
day.

Sunday will be mild again as northwest flow dries out. A Lee
trough forms again Sunday night...so winds should increase for
western locations such as Livingston and Big Timber. Twh

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

Models are in good agreement through the majority of the
extended. Current forecast looks to be in good shape so have only
made a few minor adjustments. A weak northwest flow aloft will be
over the forecast area Monday as high pressure ridging begins to
build across the West Coast. This ridge builds across the northern
rockies through Wednesday resulting in dry and mild conditions.
Weak Lee-side troughing will set up during this period as well
resulting in breezy conditions at times. Models bring a weak upper
level disturbance across the forecast area Wednesday night into
Thursday bringing a slight chance for a shower. Models then show a
strong ridge building across the northern rockies by the end of
next week into next weekend. Outside of the Wednesday
night/Thursday shower chance...dry conditions will prevail through
the period along with above normal temperatures. Hooley

&&

Aviation...

Some low-level wind shear is expected across much of southern Montana
and north central Wyoming until between 06 and 10 UTC now that surface
winds have decoupled from stronger winds aloft. Otherwise...there
will be minimal weather impact to aviation the next 24 hours with
prevailing VFR conditions and only a relatively low probability of
high-based showers Saturday afternoon and evening. Schultz

&&

Preliminary point temp/pops...

Sat sun Monday Tuesday Wednesday Thursday Friday
-----------------------------------------------------------
bil 030/058 030/056 035/062 035/064 036/062 036/063 037/059
01/east 20/u 00/u 00/u 01/b 12/west 22/west
lvm 034/057 027/055 035/059 037/060 039/063 036/059 034/058
00/north 10/u 00/u 00/north 01/b 12/west 22/west
hdn 027/057 027/057 031/063 032/066 033/063 032/064 034/062
01/east 20/u 00/u 00/u 01/b 12/west 22/west
mls 027/051 027/053 032/061 033/062 032/060 034/060 032/057
04/west 20/u 00/u 00/u 01/b 11/b 21/b
4bq 024/052 024/052 028/061 030/063 030/063 031/062 032/059
02/west 20/u 00/u 00/u 00/b 11/b 22/west
bhk 025/049 022/051 029/059 031/060 029/057 029/058 030/053
04/west 20/u 00/u 00/u 00/b 11/b 11/b
shr 026/052 025/051 027/060 029/062 031/063 031/061 033/059
00/b 20/u 00/u 00/u 01/b 12/west 22/west

&&

Byz watches/warnings/advisories...
Montana...none.
Wyoming...none.

&&

$$
Weather.Gov/Billings

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