326
FXUS65 KRIW 050431
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
931 PM MST Wed Nov 4 2026

.KEY MESSAGES...

- High clouds continue to push through from the south and east
  with the upper level low over Colorado making its slow
  eastward progression overnight. Isolated (<10%) showers
  across Sweetwater County but rest of CWA will be dry with
  seasonable overnight low temperatures.

- Another weak shortwave pushes in from the Southwest with
  isolated showers (<10%) west of the Divide, mainly higher
  elevations Thursday afternoon. Overall, most will be dry with
  seasonable temperatures continuing.

- Overall dry conditions and light winds with seasonable
  temperatures continue through the rest of the week. Above
  average temperatures expected starting Sunday into the middle
  of next week.

&&

.UPDATE...
Issued at 1139 AM MST Wed Nov 4 2026

A quick-moving low is traversing eastwards across Utah and Colorado
today. Clouds associated with this system are seen on current
satellite over the southern half of Wyoming, as high pressure to the
north keeps moisture suppressed. Some very light returns are seen on
radar from Afton to Rock Springs, with little to no impacts. This
system is the extent of weather for the next 24 hours, as otherwise
dry and seasonal conditions are in place.

&&

.DISCUSSION...
Issued at 121 AM MST Wed Nov 4 2026

Conditions remain quiet this morning, as high clouds have moved over
areas west of the Divide in the last several hours since Tuesday
evening. These are due to a closed low pressure system that is
moving over northern UT currently and will continue to track
eastward through the day today. Isolated light rain showers will be
possible along and south of a Afton-to-Rock Springs line this
afternoon as this system moves over CO. Little to no impacts will
occur due to a lack of instability and any possible measurable
precipitation is likely to occur closer to the low center over
southern Sweetwater County. Otherwise, conditions will be benign
across the CWA with seasonal temperatures and light winds. These
conditions will be in place again Thursday as an area of high
pressure shifts over eastern MT/the western Dakotas. Above
normal temperatures will return for much of Johnson County as a
result.

A trough will move over the region on Friday, shifting the area of
high pressure over the Dakotas and Upper Midwest. No significant
impacts are expected with the passage of the trough, however the GFS
is progging a low chance for rain over northern portions. A broad
ridge will then build over much of the Intermountain West and extend
over the Northern Rockies by Saturday keeping conditions dry.
Temperatures then trend above normal across the CWA by Sunday and
remain in place through the middle of next week as the ridge folds
over. Conditions also look to stay dry through this period, with a
weak trough possibly moving over the area on Tuesday.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 930 PM MST Wed Nov 4 2026

VFR conditions expected for the entirety of the period at all
TAF sites. Light winds less 10kts throughout outside of a gust
up to 18kts at CPR during peak heating of the afternoon
Thursday. Otherwise, mid level ceilings after 18-20Z west of the
Divide with showers in the vicinity of JAC through 00Z but
mainly hearing the higher terrain. This will cause some lower
but VFR ceilings and mountain obscuration along the Tetons to
Gros Ventres, as well as near the northern Winds for BPI/PNA.
Dry conditions elsewhere with no other weather elements expected
at this time.

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.

&&

$$

UPDATE...Wittmann
DISCUSSION...LaVoie
AVIATION...Lowe