162
FXUS65 KRIW 112323
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
523 PM MDT Sat May 11 2024

.KEY MESSAGES...

- Generally quiet weather, with above normal temperatures
  expected through the week, with weak ridging in place.

- A series of weak shortwave will bring afternoon shower chances
  (15 to 25%) to the higher terrain through the weekend.

- Stronger shortwaves early and mid-week will promote more
  widespread shower and thunderstorm chances.

&&

.DISCUSSION...
Issued at 1256 PM MDT Sat May 11 2024

Our weather remains quiet, which means that the mostly clear skies
that we had all night will continue through today. The clear skies
last night allowed us to view Nature`s light show, and what a show
it was. If you didn`t catch the aurora last night, another night of
mostly clear skies will allow you another chance tonight. Weak
ridging will keep mostly quiet weather and warm temperatures across
the region through the weekend and even through much of next week.

Temperatures today will be around 5 degrees above normal with
widespread 70s east of the Divide and upper 60s to near 70 across
lower elevations west of the Divide. Temperatures will be another
few degrees warmer Tomorrow and even warmer yet on Monday. Highs on
Monday will be close to 15 degrees above seasonal normals across
much of the region. A slight cool down back to near normal temps
looks to occur mid-week, but temps quickly warm back up late in the
week. Flow remains weak, so winds will be light through the week as
well.

Now, it won`t be perfectly quiet weather, as there are a series of
shortwaves that will pass through the region, one per afternoon
through Tuesday. Today`s will be limited to a few very isolated
showers across thigh northern mountain peaks. Perhaps up to a 20%
chance of showers for a brief time this afternoon in the highest
peaks of the Bighorns and Absarokas. Tomorrow will be a very similar
situation, however, PoPs are more in the 30 to 40% range for the
Bighorns. Could even see some showers develop off the Bighorns and
slide across Johnson County (20% chance). Overall though, no real
impacts. Monday`s shortwave will be a bit more potent, and showers,
along with thunderstorms, look to be more widespread across areas
east of the Divide, particularly the Bighorn Basin and Johnson and
Natrona Counties. Tuesday`s will be even more potent, with showers
and thunderstorms looking to be widespread across the region,
especially east of the Divide, with showers continuing through the
day Wednesday. Thursday and Friday look to be quieter on the
precipitation front, though westerly winds do look to increase
slightly as the gradient tightens with a messy cluster of low
pressure systems to the north over Canada. Details with any of these
shortwaves (particularly the more potent ones Monday and Tuesday)
are not able to be resolved yet, so strong thunderstorm chances,
precipitation amounts, and impacts are still uncertain at this
time.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 522 PM MDT Sat May 11 2024

VFR conditions will continue through the TAF period, with clouds
scattering out and skies becoming mostly clear again after 06Z.
There is a chance the aurora returns tonight, so this would be
favorable for any viewing. CU clouds begin to develop over the
mountains after 18Z. There will be a 10-20% chance for showers and
thunderstorms from these CU clouds, with the better odds occurring
over the Bighorns. Again, no direct impacts from this convection is
expected at any terminal.

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...Hensley
AVIATION...LaVoie