Mayoworth, Wyoming Weather Forecast Discussion

230
FXUS65 KRIW 121121
AFDRIW
Area Forecast Discussion
National Weather Service Riverton WY
521 AM MDT Fri Sep 12 2025
.KEY MESSAGES...
- Another day of afternoon showers and thunderstorms with gusty outflow
  winds being the main concern.
- A second round of showers and storms moves through the state
  during the late evening with higher chances for measurable
  rainfall.
- Chances for showers and thunderstorms persist through Saturday with
  a lull in activity for Sunday.
- Cooler temperatures will lead to light snow accumulation
  across the higher elevations mostly above 10000 feet.
&&
.SYNOPSIS...
Issued at 128 AM MDT Fri Sep 12 2025
A trough continues to dig across the Great Basin today gradually
making its way eastward. Impacts as a result of this disturbance
have continued to lessen over the past few days. Originally two lows
were expected to develop across the northern and southern portions
of the trough. However, recent trends have shown the southern low
quickly becoming disorganized west of the area and possibly not
reorganizing until its to the east of the area. As a result the bulk
of the impacts will remain to the north and south of the CWA.
Embedded shortwaves associated with the trough will move
through the region bringing chances for precipitation in the
form of daily showers and thunderstorms. Long range models
indicate the chance for another disturbance arriving by the
first half of next week. As of this morning impacts have shifted
slightly south bringing chances for precipitation into parts of
central WY.
&&
.DISCUSSION...
Issued at 128 AM MDT Fri Sep 12 2025
Showers and thunderstorms return to the state today with coverage
being more widespread as the trough axis nears. Cooler temperatures
slightly below normal are forecast west of the Divide with highs in
the upper 60s to low 70s. East of the Divide remains warm but with
temperatures beginning to gradually cool as highs range in the upper
70s to low 80s. Winds increase during the afternoon with occasional
breezes mainly around 20 mph. The atmosphere remains dry but not to
the same extent as Thursday with lesser dewpoint depressions of only
30 to 40 degrees. Showers and thunderstorms will be possible once
again starting in the early afternoon and spreading to the
northeast. Strong gusty outflow winds of 40 to 50 mph nearby any
showers or storms will be possible. Moisture looks to increase
during the evening as a second round of showers and storms moves
across the state. The influx of moisture should allow for rainfall
to reach the surface resulting in some measurable precipitation.
These showers and storms look to gradually move out of the area
by the late evening into the early morning hours on Saturday.
The trough axis enters the area by Saturday with shortwaves moving
across the state through the day. This will lead to continued
chances for showers and thunderstorms Saturday through Sunday
morning. Temperatures will continue to cool over the weekend with
highs west of the Divide in the mid 60s and highs east of the Divide
in the mid to upper 70s. Some high elevation mountain snow is
possible as these showers move through on Saturday. Snow
accumulation will be very minimal and limited to the highest
elevations above 10000 feet.
Long range models show a brief lull in activity for most of Sunday
before the next disturbance moves in from the PACNW. The exact
impacts from this disturbance remains uncertain at this time but
trends have shown a slight shift south. If this were to occur
precipitation chances would not only be limited to northern and
western WY but also central WY. Cooler temperatures will be
associated with this disturbance for the middle of the week leading
to below normal highs for much of the CWA. Along with cooler highs
overnight low temperatures may be chilly in some areas, leading to
the potential for morning frost, especially across western and
southern WY. These cooler temperatures will increase the chances for
some more light snow accumulation across the highest elevations
mainly above 10000 feet as this disturbance enters the region.
At this time confidence remains low regarding the track of this
disturbance and its impacts. Depending on its track we could see
cooler temperatures and greater chances for precipitation or
the opposite.
&&
.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 517 AM MDT Fri Sep 12 2025
Light showers continue to drift to the northeast across western
WY this morning, but have had minimal impact on local airports.
Expect showers and thunderstorms to become more numerous this
afternoon, moving from SW to NE through the afternoon and
evening. Chances for precip at some locations has increased, so
have brought VCSH and TEMPO groupings for most areas today for
increased confidence. Some shower activity will again last
beyond 00Z, and may continue well into the overnight hours.
&&
.RIW WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SYNOPSIS...Dziewaltowski
DISCUSSION...Dziewaltowski
AVIATION...Straub

NWS RIW Office Area Forecast Discussion