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Area forecast discussion 
National Weather Service Riverton Wyoming
237 PM MST sun Dec 28 2014

Short term...tonight through Monday

Winter weather advisories remain in place across the area for tonight
and for areas east of the Continental Divide for Monday morning.
Most of the mountain areas receiving light snow today and Arctic
cold front set to surge south across the area tonight with widespread
light snow...fog...and areas of blowing snow developing through
the evening. Strong north northeast winds will produce bitter cold
wind chill temperatures. As the Arctic high pressure settles in
over the area on Monday...winds will decrease and light snow will
taper off to flurries and ice fog with thin stratus hanging over
the valleys and basins with partial clearing over the mountains.

Long term...Monday night through Sunday

Snowfall will weaken across the area Monday night as the creating
system moves further away from the area. Though snowfall will
weaken...the Arctic related temperatures will continue...with frigid
temperatures expected Monday and Tuesday nights. Temperatures will
struggle to reach the single digits during the day on Tuesday with
many areas remaining subzero.

Temperatures will be able to warm Wednesday...but kept some areas
below guidance due to expected snow depth. Clearing skies are also
noted...which may result in areas of fog across the favored low
lying areas. Fog may be fairly constant between Wednesday morning
and Thursday morning.

Models begin to significantly diverge Friday afternoon...with models
showing drastically different solutions. The European model (ecmwf) shows a building
area of high pressure with dry conditions and warming temperatures
Friday and through the weekend. The GFS...meanwhile shows another
approaching system...which could produce some widespread snowfall
across the forecast area. Took a more middle ground solution to the
precipitation forecast next weekend in hopes that agreement improves
between the model solutions.

&&

Aviation.../00z issuance/

East of The Divide...kcod/kcpr/klnd/kriw/kwrl routes

MVFR to IFR ceilings and visibilities reduced in snow...fog and
areas of blowing snow will become widespread from north to south
behind an Arctic cold front that will move across the area from
00z to 06z. Gradual improvement will occur as the Arctic high
pressure center settles in across the area Monday from 18z to 00z
Tuesday and partial clearing occurs.

West of The Divide...kbpi/kjac/kpna/krks routes

MVFR to IFR ceilings and visibilities reduced in snow...fog and
areas of blowing snow will be widespread. An Arctic cold front
ill move across the area from 03z to 09z. Gradual improvement
will occur as the Arctic high pressure center settles in across
the area Monday from 18z to 00z Tuesday and partial clearing
occurs.

&&

Fire weather...

Widespread snow cover with Arctic air spreading light snow...fog
and areas of bl0wing snow...will make for bitter cold temperatures
Monday and Tuesday. Very low mixing heights with poor smoke
dispersal are expected into middle week.

&&

Riw watches/warnings/advisories...
Winter Weather Advisory until noon MST Monday wyz003>011-026>030.

Winter Weather Advisory until noon MST Monday wyz015>020-022.

Winter Weather Advisory until 5 am MST Monday
wyz001-002-012>014-023>025.

&&

$$

Short term...c.Baker
long term...branham
aviation...c.Baker
fire weather...c.Baker

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