074
FXUS65 KRIW 032207
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
407 PM MDT Mon Jun 3 2024

.KEY MESSAGES...

- Rain continues today. Chances decrease after sunset, lingering
  across northwestern and northern Wyoming through about
  sunrise Tuesday.

- Warm and dry Tuesday through the end of the work week.
  Warmest temperatures so far this year, with many locations in
  the upper 80s Thursday and Friday. A few places may hit 90.

- Elevated fire weather Tuesday and Wednesday as a result of dry
  and windy weather.

- Minor flooding concerns through this week as a result of rain
  today and warm temperatures the rest of the week.

&&

.DISCUSSION...
Issued at 1236 PM MDT Mon Jun 3 2024

An upper level low over Saskatchewan continues to bring rain over
western Wyoming as the associated trough swings through the state
today. Highest rainfall totals will be over the mountains, where
0.25" to 0.75" additional liquid is possible through tonight. The
highest peaks may see around an inch. Rain chances spread east of
the Continental Divide this afternoon. Latest high-resolution models
have 15% to 35% chances. These showers and thunderstorms will occur,
but look to be limited in coverage. Rain begins to decrease after
sunset, lasting longest over northwestern and northern Wyoming
through about sunrise Tuesday.

There are minor flooding concerns, as rain falls on snowy mountains.
The biggest areas of concern are the western mountains and northern
Bighorns. River rises are expected through this week due to today`s
rain and warmer temperatures. We will continue to monitor this
situation through the week.

Today also brings gusty winds. The strongest winds will be across
the Wind Corridor, from eastern Lincoln County, eastward through
southern Sublette County, and through Sweetwater and Natrona
Counties. Gusts to around 45 mph are possible. Locations like Red
Canyon and Outer Drive in Casper could see the strongest gusts, to
around 60 mph possible. Also of note is the central mountains, where
gusts near 50 mph are possible through tomorrow as jet energy moves
across the state.

Drier weather Tuesday and Wednesday as a ridge begins to build in.
Combined with gusty winds of 30 to 35 mph, elevated fire weather
conditions may be in place. Thursday looks drier, but winds are not
as strong.

As the ridge builds for the latter half of the week, temperatures
climb. Thursday and Friday currently look to be the warmest days,
with highs in the 80s for much of the area. East of the Divide, some
locations may see their first 90s of the year. These temperatures are
10 to 15 degrees above average. Rain chances are very limited during
this time. No precipitation is expected Wednesday or Thursday. A
little Pacific moisture may move into the area Friday and Saturday,
sparking afternoon convection, but chances right now look to be 25%
or less. Temperatures stay warm through the weekend, with highs
in the 80s.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 405 PM MDT Mon Jun 3 2024

An energetic weather system is moving from Idaho through
Wyoming and Montana this evening and overnight, continuing to
bring moisture from the WSW into western Wyoming. Light rain
continues across much of western Wyoming early this evening,
with brief periods of moderate rain possible through 02Z.
General VFR conditions may become MVFR at KJAC/KBPI/KPNA
through 03Z due to the precipitation and lowered ceilings and
visibilities. KCOD/KLND/KRKS also have a chance of showers at
varied periods this evening, with KCOD seeing the slight chance
of showers around 06Z. The mountains across western Wyoming
will be obscured through 12Z as the trough moves eastward into
the Northern Plains. Windy conditions of 15-20 kts with gusts
25-35 kts will continue at all TAF sites through 02Z-03Z. They
will decrease after sunset, but some sites will see breezy and
gusty winds through the night. Behind the trough passage Tuesday
morning, drier northwest flow moves over the forecast area. WNW
surface winds will again increase and be gusty from 15Z into
the afternoon, as isolated showers are only expected over far
northwestern WY.

Models are showing some indications of mountain wave activity along
the east slopes of the Wind River and Absaroka Mountains from
the start of the TAF period 18Z. This pattern could create
increased winds above the foothills, but at elevations of 3-8K
feet above the ground.

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.

&&

$$

DISCUSSION...Wittmann
AVIATION...McDonald/LaVoie