446
FXUS65 KRIW 110447
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
947 PM MST Wed Dec 10 2025

.KEY MESSAGES...

- Light snow showers linger overnight across Yellowstone and the
  Bighorns ending before sunrise Thursday morning.

- High Wind Warnings remain in effect across southern WY where
  periodic gusts of 50 to 60 mph or more will be possible
  overnight, to include the Wind River Basing through midnight.

- Mild, dry, and breezy conditions prevail across much of the
  Cowboy State through the upcoming weekend.

&&

.UPDATE...
Issued at 1233 PM MST Wed Dec 10 2025

Not much to add in terms of the short term forecast. The bulk of the
precipitation across western WY has come to an end as of this
afternoon. As a result of this, Winter Weather Advisories and Winter
Storm Warnings across western WY have been cancelled early. A Winter
Weather Advisory is still in effect across the western Bighorns due
to some additional light snow accumulation of 1 to 3 inches through
the afternoon. Otherwise, the High Wind Warning over southern
Lincoln County has been cancelled. This is the result of lesser
chances for winds of 50 mph or more. Gusty winds are still forecast
but currently only ranging from 25 to 35 mph with periodic gusts
around 40 to 45 mph. Besides a few changes in highlights the
forecast remains mainly unchanged with well above normal
temperatures persisting across the area through the weekend.
Precipitation chances continue to be nearly non existent across
much of the state with the one exception being western WY.
Looking ahead, this pattern is expected to prevail through much
of next week with a possible shift by the second half of the
week.

&&

.DISCUSSION...
Issued at 218 AM MST Wed Dec 10 2025

The broad ridge across the western US continues to impact the
overall lack of any semblance of a winter season so far across
Wyoming, and does not look to improve this outlook for at least
the next week. The current tap of moisture off the Pacific has
been able to produce snowfall for the western mountains, but the
warm lower valley temps keeps any precip as rainfall. A passing
wave to the north will continue produce another 3 to 6 inches
of snowfall for the western mountains, but the western ridge
will build slightly this afternoon, pushing the moisture tap
farther north, ending precip by this evening. The passing wave
and cold front will keep the local gradient tight, resulting in
strong and gusty winds across southern WY. A High Wind Warning
remains in effect as gusts could still reach 60mph, but the
frequency could be lower this afternoon. Temperatures remain
particularly warm, with highs in the 40s and 50s for lower
elevations, running about 5 degrees under record levels.

Another cold front passes by to the north in Montana Thursday
through Saturday. The moisture and energy will just clip far
northern WY Thursday night into Friday morning, bringing another
quick round of snowfall to the YNP, the Absarokas and the
Bighorns, with minimal to no snowfall expected from the Tetons
southward. The only other area of concern would be northern
Johnson County, which could get a brief push of colder
temperatures Friday, and some brief snowfall and gusty northwest
winds could bring brief travel hazards Friday night along I-90.

For the remainder of the region, the ridge will keep the warm
temperatures in place through the weekend, with highs stuck in
the 40s and 50s. This is troublesome for anyone that actually
wants winter to arrive, especially local outdoor hockey teams
that still don`t have hockey rinks for practice!

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 945 PM MST Wed Dec 10 2025

VFR conditions at all TAF sites to start the period and much of
Thursday. Windy conditions persist at COD/CPR/RIW overnight with
a persistent westerly flow aided by a low level jet pushing
over Yellowstone. Mid and upper level clouds throughout the
period increasing in coverage late after 00Z with the next
system. With that, winds stay elevated at all TAF sites, highest
at RKS up to 30kts and other locations 18-25kts. With the
aforementioned system skirting to the north, only COD will see
a chance for snow on station after 03Z and into the next TAF
cycle. Indications are for at best MVFR conditions with possible
IFR after this point in time. Mid level ceilings at all other
sites linger overnight into Friday before lifting and all
remaining dry into the weekend.

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

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 5 AM MST Thursday for WYZ019-020-022-
028>030.

&&

$$

UPDATE...Dziewaltowski
DISCUSSION...Straub
AVIATION...Lowe