208
FXUS65 KRIW 141739
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1039 AM MST Fri Nov 14 2025

.KEY MESSAGES...

- Strong west winds gusting 35 to 45 mph from Muddy Gap through
  Casper and the Lee of the Absarokas today, with locally
  stronger gusts 50 to 60 mph possible.

- Light convective snow showers continue across the northwestern
  mountains today and this evening with snow levels generally at
  or above 9,000 feet.

- It remains warm, with near record high temperatures possible
  again today.

- There will be a transition into a cooler and more active
  pattern starting Sunday and continuing into next week.

&&

.UPDATE...
Issued at 1036 AM MST Fri Nov 14 2025

Light rain and mountain snow showers will persist across the
northwest through the evening. Snow levels generally remain above
9000 feet, with rain showers across the valleys. Precipitation will
be convective in nature, and there have even been a lightning strike
or two observed earlier this morning near the Beartooths. Brief
heavier snow showers across the higher peaks and mountain passes are
the main concern today and tonight. Snow accumulations above
9,000 feet will generally be minimal, only 1 to 3 inches.

Wind is the other concern over the next 12 hours, as this shortwave
pushes through. Gusts 35 to 45 mph will continue through much of the
day and into the evening along the Absarokas and from South Pass to
Casper. Isolated stronger gusts 50 to 60 mph are possible across
favored locations including Chief Joseph Hwy and the Clark area
(north of Cody) as well as Fales Rock and Casper Outer Drive (Hwy
258). Winds will gradually decrease after around 9-10PM this
evening, and will continue to decrease through the night.

The forecast remains on track for the next weather system moving in
for Sunday night. This will kick off a cooler and more active
weather pattern that looks to continue through much of next week.

&&

.DISCUSSION...
Issued at 251 AM MST Fri Nov 14 2025

More active weather has finally returned to the area after a long
lull. And, we have two concerns today, nothing earth shattering, but
something to talk about. That is why we write these discussions of
course. An approaching Pacific trough is the cause of this.

The first concern is snow. Radar shows some echoes over Idaho and
these will spread into western Wyoming this morning, although the
steadiest precipitation would be during the afternoon and early
evening. The best forcing looks to remain to the north, and as a
result so will the best snow. This will only be a concern for the
northwestern mountains. And, the chance of 3 inches or greater is at
most 1 out of 3 and this is in the Absarokas where impacts would be
slim to none. There is little no cold air with this system as well,
with 700 millibar temperatures only falling to minus 1, which would
keep snow levels to 8000 feet or higher. So, no highlights will be
needed. Downsloping flow should keep areas East of the Divide
largely dry though. But this leads into the second and possibly
greater concern.

And this concern is strong wind. We did give some thought to  a high
wind warning for Natrona County today. The 700 millibar winds have
increased to around 50 knots at times. There will also be an 110
knot jet moving across northern Wyoming, with that region in the
favored right front quadrant of it. It is a bit too far north though
for ideal forcing. As for the ensembles, the National Blend of
Models only gives around a 1 in 4 chance of wind gusts past 55 mph
along the south side of Casper, which is the main region of concern
in regards to impacts. Criteria is also higher here, needing gusts
to 65 mph. With this, we have decided to not issue. There could be
an isolated gust to 60 or 65 mph, but at this point this seems to be
the exception. The time of greatest concern may be this morning,
with gradually improving conditions later this afternoon. The
downsloping flow will also bring another unusually warm day, with
temperatures 20 degrees above normal. Some locations, like Casper,
could make a run at 70 with most lower elevations East of the Divide
having at least a 3 out of 4 chance of high temperatures over 60.

Ridging then builds back over the area for Saturday, bring a dry
day. Temperatures will be somewhat cooler, but still well above
normal for this time of year. The next weather maker in the form of
an upper level low moving northeastward from California will bring
the next chance of showers, this one more widespread than the system
today. There is somewhat better agreement today with the highest
amounts of precipitation across northern Wyoming with wrap around
moisture from a low developing in the Lee of the Rockies. Amounts
don`t look excessive at this time though. Temperatures will be
cooler with this system, but 700 millibar temperatures generally
remain above minus 4 through the period, so again it looks like
mainly rain for the lower elevations. There are still differences in
timing of the heaviest precipitation though, spanning anywhere from
later Sunday night through Monday evening. We will likely then see
more typical November weather, with near normal temperatures and a
few chances of rain and snow, although details are still fuzzy this
far out.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1036 AM MST Fri Nov 14 2025

VFR flight conditions are forecast this TAF period. KCPR and KCOD
will be the windiest terminals, with gusts ranging from 30kts-40kts
until around 02Z Saturday. Winds at KCPR remain gusty (around 25kts)
through the overnight hours. In addition to the gusty winds, LLWS is
expected at both terminals due to strong winds aloft at KCPR and
western mountain wave activity at KCOD. For all other terminals,
there is a 90% chance of wind gusts between 20kts and 30kts through
00Z before diminishing to around or below 10kts.

There are two separate light rain chances (30%) at KJAC this TAF
period, the first being 18Z-21Z and the second being 01Z-05Z
Saturday. PROB30 groups reflect both of these precipitation chances.
There are lesser chances (15-20%) of MVFR ceilings accompanying any
light rain. Where confidence is between 20-30% of MVFR ceilings, a
SCT030 or low VFR group is added. Mountain obscurations are expected
for most of the western mountains today.

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...
None.

&&

$$

UPDATE...Hensley
DISCUSSION...Hattings
AVIATION...Gerhardt