010
FXUS65 KRIW 011023
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
423 AM MDT Mon Sep 1 2025

.KEY MESSAGES...

- Smoke from wildfires will continue across the area today.

- Dry conditions, seasonable temperatures and light winds also
  return today. However, fire weather conditions will be
  elevated in the central basins and across southern portions.

- A cold front drops highs by up to 6 degrees on Wednesday. This
  also brings low chances (15%) for showers and storms Wednesday
  and Thursday afternoon, with better chances Saturday.

&&

.DISCUSSION...
Issued at 133 AM MDT Mon Sep 1 2025

Conditions will remain mostly dry today and are expected to remain
so through at least Thursday. Temperatures will be somewhat
seasonal, ranging from the upper 70s to upper 80s. Today and Tuesday
will be the warmest days, especially in the Bighorn Basin where
highs will approach the 90 degree mark. Winds will stay light,
with periods of high clouds from time to time. Elevated fire
weather conditions will also return to the central basins and
southern portions of the CWA this afternoon, as RH values become
critical in these areas. There is a 10 to 20% chance for virga
showers to develop over the Bighorn, Absaroka and Wind River
Mountains this afternoon, but these chances could go down later
today, as confidence remains low due to the overall dry
conditions. The synoptic pattern through much of the week will
be 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 by Thursday and Friday. The smoke that moved into the
area yesterday will remain in place today, keeping skies hazy.

The anticipated cold front looks to move across areas east of the
Divide starting Wednesday morning and quickly exiting the area
to the south by early afternoon. Temperatures will be slightly
cooler as a result, but will have the biggest impact over
northern Johnson County where highs will be in the lower 70s
(about 12 degrees cooler from Tuesday). A second surge of cooler
air looks to move over the Cowboy State Friday, resulting in
highs in the 70s to near 80 degrees. The ridge will begin to
shift eastward over the state by Saturday, bringing the next
chance for widespread precipitation to the CWA. Most of this
looks to be confined to areas west of the Divide for now.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 422 AM MDT Mon Sep 1 2025

VFR conditions expected throughout the period for all TAF sites.
Light winds overnight and mainly clear skies. Winds by 17Z-19Z
will remain light around 10kts or less expected. Increasing
high clouds late in the period after 00Z towards sunset as winds
decrease to 5kts or less as wind decouples. Mainly clear sky
should appear for all TAF sites between 06Z and 10Z.

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