777
FXUS65 KRIW 081733
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1033 AM MST Fri Nov 8 2024

.KEY MESSAGES...

- Chilly start to the day today, with a gradual warming of
  temperatures expected into the weekend. Highs nearing the 50s
  in some locations with an overall quiet and pleasant weekend
  expected.

- Western mountain snow makes a return to end the weekend. An
  unsettled weather pattern looks possible for next week but
  high uncertainty remains with the exact impacts and timing.

&&

.DISCUSSION...
Issued at 116 AM MST Fri Nov 8 2024

Another chilly morning across the Cowboy State today. Lows will
range from the teens west of the Divide to low to mid 20s east of
the Divide. Fortunately, temperatures look to continue to warm into
the upcoming weekend as high pressure builds back in over the
region. Highs today range from the upper 30s to low 40s west of the
Divide and low to upper 40s east of the Divide. Conditions will be
fairly pleasant to end the work week, with mostly sunny skies and
dry conditions.

The weekend will see mostly quiet weather, with warming temperatures
and dry conditions. A large and potent low pressure system that is
bringing snow to portions of eastern CO and northern NM is expected
to remain too far south for any impacts to the area. The only thing
to note regarding this system is the slight chance (20-40%) of an
isolated shower across far southeastern portions of the CWA
early Saturday morning through Saturday afternoon. Otherwise,
much of the state remains quiet for the weekend with warming
temperatures nearing the mid 40s west of the Divide and low 50s
east of the Divide.

Sunday brings the chance for some precipitation across
western parts of the state starting in the morning as a weak
shortwave moves over the region. Impacts look very minor with light
snow in the western mountains and light snow/rain in western
valleys. There looks to be a brief lull in the action come Sunday
night before more precipitation takes aim at western WY. Currently
much of the state will see little to no impacts, but it does
look like western WY has the best chance of seeing more high
elevation snow. This is due to predominately westerly and
southwesterly flow developing across the region ahead of a deep
trough that begins to move into the PACNW. This favorable flow
will aid in producing accumulating snow across much of the
western WY mountain ranges for the first half of the week.
Snowfall will be periodic with heavy rounds of snow possible at
times starting Monday afternoon lasting into Wednesday morning.
Models are showing western slopes of the Teton, Absaroka,
Wyoming, Salt, and Wind River Ranges having at least a 30-60%
chance of seeing 6 or more inches of snow come Wednesday. The
remainder of the state looks to be mostly dry with much of the
moisture being confined to western WY. The one thing to monitor
for areas east of the Divide will be strong gusty winds as the
deep trough over the PACNW nears the area. Models are showing a
greater than 30% chance of widespread wind gusts exceeding 30
mph at times starting late Monday through late Tuesday. The
trough looks to make its way into the region by mid week with
very low confidence in the forecast at this time as models have
a loose grip on possible outcomes. Overall, things look to be
trending drier with a less likely chance of seeing widespread
precipitation as the trough moves through.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1033 AM MST Fri Nov 8 2024

VFR conditions will prevail through the forecast period. Winds will
remain less than 10 kts at all terminals through the period. The
exception will be KRKS, where southwest winds of 10 to 12 kts are
possible by 13Z Saturday. High cloud cover (around FL200 to FL250)
will increase in coverage from east to west through the afternoon as
an upper low moves north out of Colorado this afternoon.

There is a 50% chance of precipitation at KCPR after 11Z Saturday as
a result of the aforementioned weather system. Notably,
precipitation type will be highly dependent on surface temperatures.
Precipitation should generally prevail as rain, however, there is a
30% chance that rain could fall as freezing rain or freezing drizzle
early Saturday morning. There is only a 10% chance that
precipitation type will be snow. Precipitation will continue through
18Z Saturday.

There is also a 20% chance of fog or low clouds developing at KJAC
Saturday morning. Not enough confidence to include a PROB30 group,
but have mentioned a FEW002 group to hint at the potential for low
clouds.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for
the latest information on smoke, icing, and turbulence
forecasts.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Dziewaltowski
AVIATION...Hensley