Area Forecast Discussion
Issued by NWS Riverton, WY

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FXUS65 KRIW 170258

Area Forecast Discussion
National Weather Service Riverton WY
858 PM MDT SUN OCT 16 2016

.UPDATE...Added zone 23 to the Winter Weather Advisory as rain
has changed to snow in many places. Snow is also occurring
around Big Piney/Marbleton as well.

.SHORT TERM...Tonight Through Wednesday (Issued at 202 PM MDT)

The busy short term period continues. Winds have been rather robust
today with many areas gusting 40 to 50 mph with a few high wind
spots like Clark and Lander in the lower elevations and Chief Joseph
and Mt. Coffin in the higher mountains. Winds will continue to be a
concern through Monday. Next approaching system will push a front
across by Monday morning along with very strong mountain top winds.
Have issued high wind watches for Fremont and Sweetwater Counties
from 9 am Monday through 6 pm Monday. Western Hot Springs and
Southern Park look quite windy also with potential high winds. Snow
will be the concern out west. Tops are cooling over Northern Nevada
and up into far Srn Idaho. Yesterday`s front has stalled out over
the far southwest and this will be energized as this next shortwave
approaches this evening. Precipitation should increase in intensity
and coverage quickly this evening as the left front quad of the jet
coincides with the mid level convergence (sw-w winds). Best jet
divergence may end up being too far north but the upglide and mid
level convergence combined with the vort max should produce a
pretty significant swath of pcpn in the sw mtns tonight that will
gradually work nwd overnight into the Tetons. South Pass may be a
problem Monday morning with heavy snow and 50 mph winds. A swath
of cold rain or mixed rain and snow at slightly higher locations
will likely move east of the divide later tonight into Monday
morning. A little snow will likely linger out west Monday night in
advance of our next system for Tuesday. This one won`t have the
moisture or forcing that our tonight/Monday system will have but
it`ll be cold and unstable with frequent mountain snow showers and
a chance of snow showers elsewhere. Wednesday will be chilly and
unsettled in the cold nw flow with the potential for snow showers
across the mountains and lower elevations east of the divide,
especially the far north and east.

.LONG TERM...Wednesday Night Through Sunday

All in all a return to a fairly quiet period of weather after an
active beginning of the week. Any leftover showers with the
departing trough and unstable northwesterly flow should be ending
during the evening with mainly dry weather returning for later at

Following that, dry weather will be the rule. Thursday looks to be a
dry but cool day with chilly temperatures aloft, but warmer than on
Wednesday. As ridging continues to build across the state and flow
turns more westerly,temperatures should return to near or above
normal levels for Friday and Saturday. There will be some breezes in
the favored locations, but nothing out of the ordinary for Wyoming.
A weak cold front will approach the area late Saturday into Saturday
night. However, the front appears to be moisture starved with most
of the upper level support remaining in Montana. As a result, we
kept the forecast dry. Another front will approach from the
northwest late in the weekend. However, this far out there are some
timing differences with the European about 24 hours faster
than the GFS. For now, we kept the forecast dry with the best chance
of any showers likely holding off until Monday of next week.




Rain and snow in the west with snow in the mountains. MVFR
to IFR conditions will be common through Monday morning. Expect
mountains to be obscured. Conditions will improve after 18Z as
the snow shower coverage decreases in the valleys. Snow showers
will linger in the mountains through 00Z Tue, then decrease to
scattered snow showers. Strong wind is expected in southern WY
Monday with wind gusts to 55 mph. The wind will decrease after
00Z Tue.


Scattered rain showers overnight through Monday morning. Local
MVFR conditions may occur. Strong wind will develop after 15Z
as a cold front moves through the region. Wind gusts to 55 mph
are expected in some locations. The wind will decrease after
00Z Tue. VFR conditions will prevail at the terminal sites
through the period.



Fire danger low to moderate all areas through the beginning of the
work minimum RH values remain above 25 percent over those
areas in central Wyoming where fuels remain critical. That said, a
vigorous upper level weather system will begin to influence the
forecast area this evening with increasing precipitation west of the
Divide and strong winds east of the Divide through Monday. High
winds may occur again on Monday over Fremont and Sweetwater
Counties. Widespread snow will fall out west through Monday with
scattered rain and snow showers east of the divide Monday. Tuesday
will be cool and breezy to locally windy with a chance of mixed rain
or snow showers or just snow showers.


.RIW Watches/Warnings/Advisories...

High Wind Watch from Monday morning through Monday afternoon for

Winter Weather Advisory from 6 PM this evening to 6 PM MDT
Monday for WYZ012-014-023-024-025.



LONG TERM...Hattings
FIRE WEATHER...Skrbac is the U.S. government's official web portal to all federal, state and local government web resources and services.