776
FXUS65 KRIW 070849
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
249 AM MDT Fri Jun 7 2024

.KEY MESSAGES...

- Above normal temperatures will continue the threat of rising
  rivers and minor flooding today.

- Isolated thunderstorms are possible today and Saturday, with a
  better chance of storms for Sunday and Monday.

- Drier and warmer weather is likely to return for the middle of
  next week.

&&

.DISCUSSION...
Issued at 242 AM MDT Fri Jun 7 2024

We have two main concerns with the weather this morning. The first
is the potential for convection and the second is for flooding
concerns. I will address the flooding in a separate hydrology
section though.

Radar currently shows a few light showers across southwestern
Wyoming early this morning. These should not cause to much impact.
An approaching cold front, although a weak one, will bring a chance
for convection this afternoon and evening. There is not a ton of
moisture to work so coverage should be fairly sparse and
largely confined to in and near the mountains (the chance is
less than 1 out of 4 in most locations). There is a concern
though with the threats. The Storm Prediction Center has put
southwestern portions of our area under a marginal risk of
severe weather. With soundings showing the inverted V signature,
there could be strong wind gusts with any thunderstorm or even
innocent looking shower, those infamous little green blobs.
This looks largely like a diurnal event, but a few showers could
linger in eastern Sweetwater Count late tonight with some upper
level divergence from a weak right rear / left front jet
couplet. Otherwise, it looks like another warm to hot day with
our warmer spots likely taking another run at 90. Wind will also
be breezier than yesterday with the approaching front, but high
wind is not expected.

Saturday looks to be a slightly cooler day. There will be a few
showers and storms around again. Most guidance is focusing the
best coverage on southern portions of the area with a small jet
stream moving through the flow. The best chance of showers and
storms looks to be Sunday and Monday as a deeper trough
approaches the area with more moisture. Placement of heaviest
precipitation is still in flux though. With more cloud cover.
temperatures look near to below normal through the these two
days.

Following that most guidance of the deterministic and ensemble
varieties shows the ridge building back northward, bring a return of
above normal temperatures and lesser chances of precipitation. There
could be a chance of a shortwave moving through from time to time,
but there is little model agreement on this. The best chance
would be across the north but even here most areas should stay
dry on any given day. We made few chances to continuity as a
result.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 943 PM MDT Thu Jun 6 2024

VFR conditions throughout the entirety of the period. Light
winds and mainly clear skies overnight ahead of a weak upper
level system that will skirt by to the north. Models have
indicated a bit stronger winds Friday afternoon gusting up to
18-25kts at all locations by 18-21Z behind a weak frontal
boundary. Otherwise, dry conditions with winds diminishing after
01-03Z with radiational cooling and a  gradient behind the
surface boundary. No other weather elements are expected at
this time.

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 242 AM MDT Fri Jun 7 2024

Another day of temperatures averaging 10 degrees above normal will
continue high elevation snowmelt will continue the trend of rising
rivers and minor flooding. We will continue the flood advisories for
Medicine Lodge Creek, Ten Sleep Creek and the Popo Agie Rivers.
Larger main stream rivers, especially the Wind and Little Wind
Rivers, are seeing rises and will have to be monitored for possible
rises today and into the weekend.

&&

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

&&

$$

DISCUSSION...Hattings
AVIATION...Lowe
HYDROLOGY...Hattings