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fxus65 kriw 180322 

Area forecast discussion
National Weather Service Riverton Wyoming
922 PM MDT Tue Sep 17 2019

Short term...overnight through Wednesday
issued at 920 PM MDT Tue Sep 17 2019

The weather system has departed Wyoming this evening taking the showers
and storms with it. Parts of Big Horn County got a decent rainfall
with Greybull Airport logging 0.62 inches. Lingering clouds over the
north and northwest will gradually dissipate overnight. The gusty
wind has subsided in many locations, but some spots are holding on
to gusts as of 03z. Wind will subside as the night GOES on. Low
temps in the west will be in the 20s and 30s, with 30s and 40s east
of The Divide.

Wednesday will be dry with mild high temps. Flow aloft will become
SW in response to the digging trough of low pressure over the northwest U.S.
Some local breezes Wed afternoon in the normal wind corridor from
krks to kcpr.

Long term...Wednesday night through Monday
issued at 1151 am MDT Tue Sep 17 2019

The aforementioned trough will continue its track over the
northern Great Basin Thursday (similar to today's storm system).
The associated cold front will be along the Idaho/Wyoming border during
the day Thursday, gradually moving over western portions Thursday
night. The progression of this storm system will be slower,
compared to today's storm, and gradually make its way over the
cowboy state and over the northern plains by 12z Saturday. The
entire area will have increased precipitation chances from
Thursday night through Saturday. The northwest will see the most
precipitation through that period and Friday will be the wettest
day across the area. Snow levels will be variable, ranging between
9000 to 10kft for much of the area. Snow levels will range between
7500 to 8500ft over northwestern portions. Conditions will improve
across the area Saturday, as the storm exits toward the upper
Midwest. Sunday will bring a dry reprieve, right before yet
another system potentially impacts the region on Monday. Early
indications have this system cutting off over the Great Basin.


Aviation...for the 06z tafs through 06z Thursday
issued at 920 PM MDT Tue Sep 17 2019

VFR conditions will occur at the terminal sites through the period.
Local gusty wind at kcod, kriw, and kcpr will subside overnight.
Wednesday will see mainly clear conditions with light wind speeds.
Kcpr will see a gusty wind around 18z Wed through 01z Thursday.


Fire weather...
issued at 1151 am MDT Tue Sep 17 2019

A cold front will sweep across the region today, keeping
temperatures in the 50s and 60s during the day. This will keep
humidity values higher than the past couple days, with most areas
only falling to 25 to 35 percent during the afternoon. Areas of
zone 280 may still get warm enough for humidity to fall below 20
percent this afternoon. Southwest to west winds will increase
considerably this afternoon, with gusts reaching 40 to 50 mph,
especially from rks to cpr. Some gusts may reach above 55 mph
around any passing showers or thunderstorms, especially for zone


Riw watches/warnings/advisories...none.



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