332
FXUS65 KRIW 131130
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
530 AM MDT Thu Jun 13 2024

.KEY MESSAGES...

- Weak convection over southern portions of the CWA Thursday.

- Some minor flooding issues due to snowmelt but most waterways
  are on the decline.

- Elevated fire weather risk Saturday afternoon.

- Cooler late weekend and into next week with low confidence
  return of moisture as well.

&&

.DISCUSSION...
Issued at 1250 AM MDT Thu Jun 13 2024

IR currently depicts mainly clear skies across the CWA with some
clouds pushing through the southern portions of the state. This
will be the area for some afternoon convection that will push
slightly north of east towards the Casper area into the evening
hours. Weak convection and short lived is expected with no
significant impacts. Otherwise, ridging will continue to extend
in from the south with a weak low over the southwestern US that
will push the aforementioned mid level support to spark a few
storms and sporadic rain showers. Much weaker winds with a more
relaxed gradient, so fire weather is not a concern.

Friday will see a bit more activity for areas east of the Divide
as a deepening low pushes out of the GOA towards the Pacific
northwest coast. A subtle shortwave looks to push through the
CWA off of it during the afternoon and early evening hours. Warm
temperatures continue with snowmelt becoming less of a concern
as waterway levels steadily decline as time goes on.

As the low slowly pushes further eastward and deepens due to
increasing divergence aloft, the gradient will tighten up on
Saturday. This will give way to some gusty southwest winds and
an elevated fire weather concern with humidity values dropping
with the warm temperatures. Troughing will continue to elongate
southward Sunday as a cold front drops through during the
afternoon hours that will make for a tricky temperature forecast
with cooler air behind it. Regardless of timing, below average
temperatures can be had to start next week and for a few days.
With the slowly approaching low as many models have it doing, an
increased chance in precipitation will follow. There is still
much discrepancy on how much and when through mid week. Nothing
looks to be a drought buster, but there should be at least some
measurable rain for most during that time span.

By mid week, the trough becomes more progressive as it speeds
into the upper Great Plains as ridging builds in behind it. This
will bring dry conditions and a warming trend once again to end
the work week and into the following weekend. All in all, mainly
quite weather conditions being hot and dry through the weekend
becoming cool and a bit wetter through mid next week before
reverting back to more of the same beyond.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 529 AM MDT Thu Jun 13 2024

Southern Wyoming is seeing scattered mid-level clouds with SKC
elsewhere. A low pressure system to the southwest will begin to
impact the area Thursday morning. This will bring more widespread
mid and high cloud coverage across the CWA. Isolated thunderstorms
will develop this afternoon and may impact KLND/KRIW/KCPR. Added a
prob30 group to Casper for 21-24Z, but less certain about TS on
station for the others. Wind will generally be 10 knots or less
across the sites unless impacted by thunderstorms/outflows. There
will be an increase this afternoon at KBPI/KPNA/KRKS, with sustained
wind of 10-15 knots, and gusts of 20-25 knots until 03Z/Fri.

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...Lowe
AVIATION...Rowe/Swanson