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fxus65 kriw 221023 

Area forecast discussion
National Weather Service Riverton Wyoming
323 am MST Fri Nov 22 2019

Short term...(today through saturday)
issued at 1259 am MST Fri Nov 22 2019

The main issue for today will how quickly the stubborn low clouds
and fog across central/southern areas dissipate today and the
impacts on highs. The northern areas will be sunny with seasonal
to above average temperatures.

Over the south and southwest, the clouds and flurries early this
morning are associated with a deformation axis and moisture on the
northern periphery of an upper low over eastern Colorado. This
flurries will come to an end quickly this morning with clouds
departing by midday to early afternoon as the low pushes into the

A decent inversion has set up east of The Divide with 700mb temps
0 to 2c. The will primarily impact the Wind River basin where
current low clouds and fog could be stubborn as it is caught
below a steep inversion, and has the potential to last longer than
clouds over the south where a steep inversion is not present.

The main issue late tonight will be the potential for some
breezy/windy conditions in Cody foothills to DuBois area as models
show a decent downslope flow/temp gradient. Overall the fog/low
cloud development in the basins/valleys look to be low.

Northwest flow will set up across the forecast area Saturday. Dry
and slightly warmer temperatures are expected with some increasing
clouds late in the period.

Long term...(saturday night through thursday)
issued at 1259 am MST Fri Nov 22 2019

After a dry Saturday, a cold front will approach the forecast area
with increasing pops beginning in the northwest early Sunday
morning, and then spreading across the west and north through the
day. The precipitation will then spread into central and southern
areas by Monday morning. The weather will be snow across the region,
with the highest amounts across the west. Models are overdoing the
quantitative precipitation forecast in the western valleys, so we lowered them for more reasonable
snow totals. Precipitation will decrease Monday evening and
overnight. An extensive trough will set up along the West Coast
Tuesday night setting up a strong southwest flow across the area.
This will funnel in quite a bit of moisture and bring more snow
showers to the area. These showers will spread across the state by
early Wednesday, with the majority of the snow again falling over
the west. Gusty winds will accompany both of these storm systems,
especially over the mountains and the southern wind corridor.

Cold temperatures will move in with these two systems with high
temperatures Monday through Thursday currently looking to be in the
20s and 30s with Tuesday the coldest day. As of now, most areas do
not look to even reach freezing on Tuesday. Overnight lows will drop
into the teens and single digits pretty much every morning next
week. The southwest flow will continue Thursday and Friday, with
continued moisture being pumped into the forecast area. It looks to
be a cold Holiday week with a decent chance of snow showers.


Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 1259 am MST Fri Nov 22 2019

The Wind River and the Upper Green river basins, including the
kbpi, klnd, kpna and kriw will have IFR ceilings and/or fog for
much of the morning. Most confident for the terminals in the Wind
River basin. Low ceilings over Star vally and the Upper Green
river basin are working northward to jac. Based on these trends
expect the low clouds ranging between 020-040 ft range to reach
kjac terminal by 12z. Once the low ceilings reach the kjac
terminal they could be stubborn to scatter out until early to mid

Kcpr and krks will see a gusty wind develop between 16z and 18z
and continue through 02z.


Fire weather...
issued at 1259 am MST Fri Nov 22 2019

Seasonally cool in most locations today. Poor smoke dispersal
across much of the area due to low mixing heights and mainly
light winds. Low clouds and some fog over central and southern
areas are expected to clear out in the afternoon. Slightly warmer
and dry on Saturday, but most locations will have poor smoke


Riw watches/warnings/advisories...none.



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