703
FXUS65 KRIW 192315
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
515 PM MDT Wed Jun 19 2024

.KEY MESSAGES...

- Today begins the warming trend, which will persist into the
  weekend. The first triple-digit temps of the season are
  possible Sunday and Monday.

- A wetter plume will push into WY beginning Thursday afternoon,
  with best chances for precipitation occurring Friday
  afternoon.

- Hot and dry weather will occur through the weekend and into
  the early part of next week with low confidence in any relief
  coming.

&&

.DISCUSSION...
Issued at 226 PM MDT Wed Jun 19 2024

We remain cooler than normal today as cloud cover across much of the
region has limited warming. The warmth will return though, with
temps climbing to much above normal values by the weekend. We may
even see our first triple-digits across portions of the Bighorn
Basin Sunday and Monday. The Basin/Greybull to Lovell area is the
most likely to see 100+ temps (50 - 60% chance) Sunday and Monday.
Temperatures look to moderate slightly after Tuesday, but extended
range model solutions are not showing any strong indications of a
longwave trough or moisture plume that would bring much in the way
of relief from the heat.

Before we really start to bake and dry out this weekend, we will
have one last chance for some moisture with a push of Gulf moisture
beginning Thursday evening. Today, the moisture flow will generally
be to our east, though there is a 20 chance that some isolated
showers could develop along Casper Mountain or perhaps the southern
Bighorns later this afternoon. The trough to our west will regress
westward tomorrow and even further east for Friday, allowing widely
scattered shower activity to spread into the region. Best chances
for precipitation will come Friday. Best wetting rain (>0.1 in.)
chances will be east of the Divide, particularly off the lee of the
Winds, Bighorns, and Casper Mountain. Shower chances continue
through Friday evening, then taper off after sunset. Then Saturday,
the ridge begins to build and the real warmup begins.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 515 PM MDT Wed Jun 19 2024

Weak high pressure and a fast southwest to northeast mid-level flow
over the area is keeping VFR conditions across western and central
WY through at least late Thursday afternoon. Dry conditions persist
across western WY, with somewhat moister air along and east of the
divide. Late this afternoon into the early evening may see some
moderate cumulus with light showers and very isolated thunder over
the northeast Absarokas as well as around Casper Mountain, though
they have a very low chance (10%) to impact KCOD and KCPR other than
some gusty outflow. Winds are light to breezy today with some gusts
reaching 20 kts. Some gusty east winds are likely across central WY
overnight. Clouds should increase Thursday morning, especially east
of the divide, as moisture increases from a disturbance over CO.
Isolated storms should develop over parts of central WY and the
northern WY mountains late in the afternoon Thursday, with showers
persisting overnight. While KRKS should see gusty SW winds during
the afternoon, gusty east winds will increase across central WY.
Localized MVFR conditions are possible from 20/22Z-21/06Z due to the
isolated thunderstorms and showers.

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

&&

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

&&

$$

DISCUSSION...Hensley
AVIATION...McDonald/Rowe