463
FXUS65 KRIW 281719
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
1019 AM MST Fri Feb 28 2025

.KEY MESSAGES...

- Pleasant, sunny, and mild end to February across the Cowboy
  State today.

- Quiet, dry, and mild conditions prevail through the weekend
  with highs well above normal especially east of the Divide.

- A shift in the weather pattern is expected to develop for the
  start of next week with cooler temperatures and multiple
  chances for rain/snow.

&&

.DISCUSSION...
Issued at 138 AM MST Fri Feb 28 2025

All in all, the reasoning of the forecast remains the same. Through
Sunday, it looks fairly quiet. Ridging will dominate the weather
across western and central Wyoming, bringing a period of quiet and
mild weather, with most locations seeing temperatures averaging 10
to 20 degrees above normal. A weak cold front will try to move
southward into eastern portions of the county warning area
today, possibly as far south as Casper by this evening. But the
only impact would be to knock temperatures back down toward
seasonal normals. No precipitation is expected, just an increase
in some clouds. Temperatures will warm back up for the weekend
though.

The only threat would be local flooding with the warm temperatures.
The chance has decreased in northern Wyoming, where the recent warm
weather has melted out almost all of the lower elevation snow. We
can`t rule out some local ice jam flooding, but this is looking more
unlikely by the day. The main threat for this looks to shift further
south, mainly across southwestern Wyoming. The main concern is in
southern Lincoln County, where there is still a decent amount of
snow water equivalent and the Bear River has shown some rises. Any
flooding at this time would more than likely be minor.

Things still look to turn more active early next week as the ridge
shifts to the east and is replaced by a trough and a series of
waves. We have the some problem today as yesterday. Most areas will
have a chance of some snow, with some rain at the onset in areas
East of the Divide as it will still be fairly mild on Monday in that
vicinity. The problem is there is still a lot of disagreement on the
details and with this many moving parts, details on timing and
especially potential snowfall amounts are still highly uncertain. A
first look at probabilistic guidance from Monday morning through
Tuesday night shows at last a 1 in 3 chance of an inch of snow or
more across many of the lower elevations through this period. The
chances of 3 inches fall substantially though. There are some models
showing a period of northerly upslope developing, and this is where
the best chance of 3 inches in the lower elevations is. This is
mainly in locations like Lander, Thermopolis and the south side of
Casper, but even here the chance is less than 1 out of 3 at this
time. The chance of a foot of snow or more is very small, at most
only 1 out of 4 and only over a small portion of the Wind River
Range. So, the generally outlook is most areas will have a chance at
some snow, but amounts look moderate at best and light for most
locations at this time. Temperatures will fall on Tuesday,
especially on Tuesday. However, this air is of Pacific origin so
very cold weather is not expected. Temperatures look below normal
on Tuesday  before rebounding to near normal levels for the middle
of the week.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1019 AM MST Fri Feb 28 2025

All terminals to be VFR through the forecast period. Passing mid and
high clouds will stream across the region in northwest flow aloft as
a ridge axis remains to our west. Surface winds will generally be
10kts or less with the exception of 10-13kt southwest wind
developing at KCPR late Saturday morning.

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...Hattings
AVIATION...CNJ