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Area forecast discussion 
National Weather Service Billings Montana
930 am MST Friday Feb 12 2016

Update...
water vapor imagery and upper air analysis show a ridge axis over
the Great Basin and northern rockies with a 500mb height in excess
of 570dam over south central Montana. Cold upper low dropping into the
north central Continental U.S. Has allowed for some colder low level air and
east winds to push into our County Warning Area since last night...undercutting
what is a rather strong ridge aloft. Moist overrunning of this
shallow colder airmass has allowed for areas of light precipitation in the
form of rain/snow to develop since last night. Latest radar trends
suggest an eastward movement of the precipitation already...and looks like
our western foothills will be mainly dry from this point on as
baroclinity shifts east. Have lowered probability of precipitation for our west...
including Billings which may see a little very light rain or snow
through early afternoon...but otherwise this is looking more like
a dry day for the Billings metropolitan area. There is still potential
for light snow to mix with light freezing precipitation over our east
tonight as a warm layer overruns the shallow cold...with below
freezing surface temperatures likely to occur across our east tonight. Will
need to monitor this but precipitation should remain light and somewhat
spotty...reducing the potential impacts. Temperatures today will hang in
the 30s to middle 40s across our central and eastern parts...with a
persistent light easterly wind...but should see 50s emerge along
our foothills as downslope winds develop. Jkl

&&

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

A couple of systems will impact the forecast area through the
short term. The first system is starting to make its way across
southwest Montana and approaching our far western counties. Radar
echoes are increasing but cloud bases still remain fairly high as
no precipitation has been reported across the Livingston and Bozeman
areas. Further east toward the Dakota border...a cold front backed
its way into that area yesterday and has made its way westward
past Billings early this morning. Satellite is showing a low
stratus deck from about Miles City eastward but no precipitation nor fog
has been reported. The hrrr model brings some very light shower
activity into our western areas this morning but it doesn't make
it as far east as Billings. However...the GFS and European model (ecmwf) keep
scattered areas of precipitation across our entire area today with the
best chances across our west this morning and eastern zones this
afternoon and evening. As a result...we have removed precipitation
chances this morning across the east and lowered chances just a
bit elsewhere. There will be a large contrast with temperatures
today with Baker only seeing temperatures around 30 while
Livingston could see 50 degrees.

For Saturday...a much stronger system within a northwest flow
aloft moves southeast across our area during the day and lingering
across our far eastern counties into tonight. We will continue
with a high pop chance across most areas through the day with
likely probability of precipitation across Custer and Fallon counties into tonight.
Soundings from Miles City to Ekalaka and points east show the
possibility of some light freezing rain after midnight tonight so
area roads may be slick. Temperatures Saturday will warm back into
the 50s with 40s along the Dakota borders. Hooley

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

Warm and above average temperatures will continue through next
week as a ridge of high pressure to our west is stubborn to erode.
Not expecting conditions to be as warm as this past Tuesday and
Wednesday...but temperatures will still be in the upper 50s to
near 60 in the downsloping northwest flow.

Several disturbances will push through the area during the week.
The first one will move through Monday night through Tuesday.
Expecting mostly rain with this system as air and ground
temperatures should stay above freezing. Pretty good pressure
rises behind this system also bring about the chance for some
gusty conditions late Monday through Tuesday afternoon. Though
with the best pressure rises appearing to move through at night
will not issue any highlights at this time. In addition...strongest
middle-level winds look to stay mostly west of Billings and Roundup.
A weak wave moves through Wednesday but little moisture and upper
level forcing should keep shower chances low. Last system
approaches from the southwest towards the later part of the week.
Better dynamics with this system are expected but the splitting
and weakening nature of this system should just allow for a slight
chance of probability of precipitation in the plains...with most of the western terrain
seeing any appreciable precipitation. Dobbs

&&

Aviation...

MVFR conditions possible today. Rain/snow showers possible this
morning from klvm to kmls...eventually shifting to areas east of
kbil-kshr for this evening. Light freezing rain and patchy fog are
possible east of kbil-kshr tonight. MVFR conditions then possible
at times again on Saturday across southern Montana and north-
central Wyoming. Snow showers possible Sat morning across southern
Montana...then rain showers possible Sat afternoon for southern Montana and
north-central Wyoming. Rms/jkl

&&

Preliminary point temp/pops...

Today Sat sun Monday Tuesday Wednesday Thursday
-------------------------------------------------------
bil 044 034/052 033/054 038/058 041/059 038/060 037/055
2/o 13/west 23/west 24/west 22/west 11/east 11/east
lvm 057 037/048 034/049 040/055 045/056 041/056 036/052
2/r 04/west 35/west 34/west 32/west 11/north 22/west
hdn 045 029/053 031/054 034/058 037/059 034/060 034/054
3/o 14/west 23/west 24/west 32/west 11/east 11/east
mls 037 026/050 029/052 033/054 037/054 034/055 033/053
3/S 46/west 21/b 23/west 22/west 11/east 11/east
4bq 038 028/051 030/050 032/053 037/055 034/059 033/055
3/S 34/west 32/west 24/west 32/west 11/b 11/east
bhk 030 018/043 028/047 028/048 032/049 030/050 029/050
1/east 46/west 31/b 12/west 22/west 11/b 11/east
shr 046 027/052 027/049 032/054 034/056 032/058 031/054
2/o 13/west 53/west 23/west 22/west 11/b 11/east

&&

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

&&

$$
Weather.Gov/Billings

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