255
FXUS65 KRIW 311000
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
400 AM MDT Sun Aug 31 2025

.KEY MESSAGES...

- An isolated storm remains possible (10% or less) over the
  Bighorn, Absaroka and Wind River Mountains this afternoon.

- Smoke/haze will increase over western and central portions of
  the forecast area through the day.

- It will be dry Sunday through Tuesday of this coming week.
  Temperatures will be cool to seasonal with highs in the upper
  70s to upper 80s.

- A cold front will drop highs by up to 5 degrees on Wednesday
  and Thursday. This will bring low chances (20-30%) for showers
  and storms Wednesday afternoon.

&&

.DISCUSSION...
Issued at 130 AM MDT Sun Aug 31 2025

Conditions are expected to be mostly dry for the rest of the Labor
Day weekend and Tuesday, with temperatures ranging from the upper
70s to upper 80s. There is less than a 10% chance for showers to
develop over the Bighorn, Absaroka and Wind River Mountains this
afternoon. Winds will stay light, with periods of high clouds from
time to time. The synoptic pattern this week remains largely
unchanged: the Cowboy State will be sandwiched between an upper
level ridge to the west and a strong developing longwave trough to
the east. The influence of these two features could cause some
variability for each side of the Divide. The main wrinkle today
will be increasing smoke/haze across western and central
portions of the CWA through the day. Most of the smoke will be
from the numerous wildfires in central ID.

A cold front looks to move across areas east of the Divide by
Wednesday. Models are now in better agreement with the timing and
keep the colder air well to the east. The possibility for the first
shot of fall weather has gone down and does not look like it will
happen this week. Overall, the forecast looks to stay somewhat
stable this week with mostly dry conditions and light winds.
Additionally, these conditions will keep fire weather conditions
from going critical.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 400 AM MDT Sun Aug 31 2025

Weather conditions will be very uneventful over the next 24 hours
with mostly clear skies and light wind. There will be a
northwest breeze around 10 knots at KCPR Sunday afternoon, but
elsewhere wind will remain below 8 knots through the TAF period.
Areas of smoke may move toward the western TAF sites this
afternoon, but conditions are expected to remain VFR at this
time.

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.

&&

$$

DISCUSSION...LaVoie
AVIATION...Hattings