874
FXUS65 KRIW 082044
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
244 PM MDT Sat Jun 8 2024

.KEY MESSAGES...

- Isolated showers and thunderstorms will continue to bubble up
  across southern and western WY this afternoon. These should
  dissipate around sunset.

- More widespread showers and thunderstorms return during the
  day Sunday and continue into Monday. Some thunderstorms on
  Sunday could produce locally gusty winds and small hail.

- High pressure builds into the middle of the week, bringing
  warmer temperatures and dry conditions.

&&

.DISCUSSION...
Issued at 159 PM MDT Sat Jun 8 2024

Showers have been able to develop in a band of instability
across southern WY this afternoon, aided by sfc temperatures in
the 80s. A few of these thunderstorms may still produce gusty
winds, and a few storms moving into southwest WY may bring some
isolated small hail as well.

Sunday will see the ridge shift just to the east, opening the
door for the next wave to sweep by to the north. The ridge
placement will also bring a push of deeper moisture into the
state, with forecast PW values above 0.7 inches. These factors
will bring increased instability, resulting in more numerous
showers and thunderstorms across most of the state. SPC has
expended the marginal severe threat to cover the northern 2/3 of
the state, with the main threat being gusty winds and isolated
hail. The impact will start across NW WY later Sunday, spread
east overnight, the focus impacts east of the Divide on Monday
as the trough sweeps east.

Once the trough moves east Monday evening, ridging returns to
the northern Rockies, turning off the moisture feed and letting
temperatures jump again into the 80s, possibly lower 90s through
the remainder of the week.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1123 AM MDT Sat Jun 8 2024

FR conditions are expected through the period. Usual locations will
see afternoon breezes with gusts around 20 to 25kts. Winds will
taper off after 02Z and return to light drainage flows overnight. A
few weak showers and isolated weak thunderstorms will develop across
the south this afternoon, but no impacts are expected at any
terminals. KCPR and KRKS have a 10% chance of seeing a brief shower
or gusty outflow wind from these showers, but not enough confidence
to include in the TAFs for now.

Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for
the latest information on smoke, icing, and turbulence
forecasts.

&&

.HYDROLOGY...
Issued at 207 AM MDT Sat Jun 8 2024

Rivers and creeks will remain on the high side today at Action Stage
or below, but look to remain steady for now. SnoTel sites above
9000 ft continue to drop and are now below 10 inches of SWE. At
this rate, the remaining snow at these sites could be gone in
the next couple of days. The notable exception is sites in the
Tetons and portions of Yellowstone NP, where 20-30 inches of
snow remain on the ground. Will keep the Flood Advisories in
effect as a result, likely continuing through the weekend.

&&

.RIW WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Straub
AVIATION...Hensley
HYDROLOGY...LaVoie