068
FXUS65 KRIW 101937
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1237 PM MST Wed Dec 10 2025

.KEY MESSAGES...

- Isolated snow/rain showers will linger across portions of
  western and northern WY this afternoon.

- High Wind Warnings remain in effect across southern WY where
  periodic gusts of 55 mph or more will be possible today into
  Thursday morning.

- 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 /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1055 AM MST Wed Dec 10 2025

MVFR flight conditions and light rain/snow at KJAC should begin to
improve to VFR around 20Z as winds begin to pick up. Confidence in
MVFR ceilings this afternoon is 20%-30% at KJAC, KRKS, KBPI, and
KPNA so a SCT030 or SCT035 has been added to reflect this potential.
Any low cloud/MVFR ceiling potential is forecast to end between 23Z-
02Z, with high confidence (90%+) in VFR flight conditions persisting
the remainder of the TAF period.

Gusty winds are expected at all West of the Divide terminals (KJAC,
KRKS, KBPI, KPNA), KCPR, and KCOD this TAF period. Gusty winds at
KBPI and KPNA begin to diminish between 00Z-01Z, with winds at all
other aforementioned terminals remaining gusty the entire TAF
period. However, there is a 20% chance in gusts diminishing
after 08Z at KCOD, but given confidence is low in this occurring,
opted to keep persistent gusts in TAF at this time. Winds
remain around or less than 12 kts at KRIW, KLND, and KWRL but
an occasional gust around 20kts is not out of question (30%
chance).

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...
Winter Weather Advisory until 5 PM MST this afternoon for
WYZ008.

High Wind Warning until 5 AM MST Thursday for WYZ019-020-022-
028>030.

&&

$$

UPDATE...Dziewaltowski
DISCUSSION...Straub
AVIATION...Gerhardt