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Area forecast discussion...updated 
National Weather Service Billings Montana
914 am MDT Thursday Oct 2 2014

Update...

Minor update this morning for slightly slower frontal timing. Cold
front is located just north of a Livingston to Billings to Miles
City line at 9am. Ahead of the front gusty west to southwest winds
are developing as the lower atmosphere begins to mix out some with
partly cloudy to mostly sunny conditions. Behind the front gusty
north to northwest winds and light snow can be found as
temperatures are in the low to middle 30s. Strongest pressure rises
are located between Havre and Great Falls so probably a couple
more hours before this front really surges to the southeast. Once
it does expect cloud cover to fill in and scattered showers to
develop a couple hours behind the front. Temperatures this
afternoon will hold steady or fall with most areas in the low to
middle 40s by middle afternoon and some 30s possible across the northern
tier from Harlowton to Miles City. Wet bulb temperatures support
a mix of rain and snow this afternoon over foothills with snow in
above 7000 feet. However just about anyplace could see a few snow
flakes mixed in with rain showers today. Mention of rain/snow in
the forecast is confined to those areas with the best chance of
seeing this mix. Do not expect any significant snow accumulation
below 7000 feet today or tonight. The big horns and Pryor
Mountains will see the heaviest snow accumulations based on the
northwesterly winds...could see 2 to 4 inches in these areas with
locally heavier accumulations possible. This system will quickly
exit the area this evening with a mostly clear and cold night
expected. Temperatures in the low to middle 20s can be expected in
many areas tonight. Chambers

&&

Short term...valid for today and Friday...

Active weather today as a strong jet dives south out of British
Columbia. The jet will bring a strong short wave and cold front
through our area. The cold front is expected to arrive in the
Billings area around 16z and Sheridan by 19z. There will be strong
cold air advection behind the front and this will limit heating
for the remainder of the day. Soundings indicate nearly saturated
air mass with strong Omega field from the surface to 600 mb. Weak
middle-level cape was also depicted. This forcing will bring a mix of
rain and snow showers today. The best chance for light snowfall
accumulations will be along the foothills where upslope flow as
well as the northeast Big Horn Mountains. Pressure rises along
with strong cold air advection will take place with the frontal
passage and this will create gusty north to northwest winds. The
winds and precipitation will be ending by sunset as strong
subsidence moves in. Temperatures will cool significantly tonight
and a few areas will see a hard freeze. Temperatures will fall
into the low to middle 20s for Livingston and Sheridan with upper 20s
in Miles City. Livingston will be near a record low tonight.

Friday will be dry as a ridge of high pressure begins building
over the area. Did lower high temperatures for tomorrow with 850
mb readings prognosticated to remain in the single digits. Overnight lows
Friday night will be much warmer with readings in the upper 30s
to lower 40s. Richmond



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

Seasonably warm and mainly dry weather is expected during the long
term with highs above 70 f in the lower elevations on many days as
air originating across the Pacific Ocean streams across the region
and is compressed further in large-scale downslope flow. The winds
will likely be gusty during peak heating/mixing some days too with
the highest probability of stronger winds likely to be over south-
eastern Montana on sun and Monday. It/S on those days that 00 UTC guidance
suggests a weak shortwave trough or two embedded in northwest flow
aloft may graze the area...enhancing middle-level winds.

On the large-scale...the flow will deamplify with time as a trough
becomes established over Alaska by middle to late week. Confidence in
forecast details decreases a bit in step with the transition...but
right now it merely looks like all it will mean is somewhat cooler
weather and a slightly higher chance of showers by late next week.
Schultz

&&

Aviation...

A fast-moving cold front will cross the area today...causing winds
to shift to the north or northwest with gusts between 30 and 35 knots
in many places after 18 UTC. Scattered showers are expected behind
the front along with lowering ceilings...and brief MVFR to perhaps
IFR conditions and mountain obscurations are possible. The wind...
showers and clouds will all quickly decrease this evening. Schultz

&&

Preliminary point temp/pops...

Today Friday Sat sun Monday Tuesday Wednesday
-------------------------------------------------------
bil 052 030/056 045/074 048/070 046/069 049/074 048/071
3/west 10/u 00/b 11/u 10/u 11/u 11/u
lvm 054 025/062 040/070 040/070 042/070 044/072 043/070
2/west 10/u 00/b 11/u 11/u 11/u 11/b
hdn 055 027/057 040/074 046/071 044/069 046/074 045/072
4/west 10/u 00/b 11/u 11/u 11/u 11/u
mls 051 028/054 038/070 046/069 045/067 046/070 045/067
3/west 00/u 00/b 11/north 11/b 11/b 11/b
4bq 057 029/052 037/067 045/066 043/066 044/071 045/070
4/west 20/u 00/b 11/north 11/b 11/u 11/b
bhk 052 028/047 031/065 043/062 041/063 041/067 043/065
3/west 00/north 00/b 11/north 11/north 11/b 11/b
shr 057 026/053 037/071 043/069 042/069 044/073 043/072
6/west 40/u 00/b 11/u 10/u 11/u 11/b

&&

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

&&

$$
Weather.Gov/Billings

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