539
FXUS65 KRIW 262248
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
448 PM MDT Fri Jul 26 2024

.KEY MESSAGES...

- Showers and thunderstorms are possible today, though
  confidence on timing and location remains low as models
  differ. Everywhere has at least a small of chance of rain
  today, though.

- Showers and thunderstorms possible again Saturday, starting
  mid-morning. Gusts up to around 50 mph are possible.

- A drying and warming trend begins Sunday, and especially into
  the workweek. Fire weather concerns starting Monday.

&&

.DISCUSSION...
Issued at 1226 PM MDT Fri Jul 26 2024

The cold front that passed through yesterday has brought seasonal
temperatures across the area today, with highs generally in the 80s,
with low 90s for the warmer favored locations. The main story for
today is scattered showers and thunderstorms, aided by the passage
of a shortwave this afternoon. Models continue to be variable in
their timing and coverage of storms this afternoon and evening.
Would say there is at least a 15% chance of rain anywhere in the CWA
today, though there will be many locations that do get a storm.
Though some of this convection could come with locally heavy rain,
(favored more for southern half of the area) gusty winds are the
main threat. Gusts 30 to 40 mph should be common with any storms
that develop, with gusts near 50 mph a real possibility. Some small
hail is also possible with some of the stronger storms. Overall,
support is not looking good for any widespread severe storms. Models
are consistent in ending convection by midnight.

Another shortwave moves through Saturday, this time in the morning.
This should kick off showers and thunderstorms earlier than normal.
Southwest Wyoming sees rain chances pick up after 5am MDT. These
chances spread east-northeastward through the morning, with another
day of widespread rain chances over the area for the afternoon. Like
today, models are showing various locations, coverage, and timing of
convection Saturday, so confidence is low on those aspects of the
forecast. However, it will be another day where everywhere has at
least a small chance of a storm. Gusts to 50 mph will be the main
hazard of concern again. The recent HRRR has a few gusts over 50
mph as well.

A ridge starts to build in from the south Sunday. This keeps the
best afternoon rain chances over the northern half of the area.
Otherwise, highs continue to be seasonal through Sunday. The ridge
continues to build in through next week. Temperatures climb a
little, with dry air returning. This increases fire weather concerns
starting Monday. The chance of any showers and thunderstorms also
remains very low for next week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 447 PM MDT Fri Jul 26 2024

Scattered rain showers and thunderstorms will wind down this
evening. Unless a thunderstorm moves directly over a terminal
conditions will be VFR, although smoke will move in today, so
reductions in VIS due to smoke/haze will occur at times, especially
for northern terminals KCOD/KWRL. For now have not included FU in
this TAF issuance due to uncertainty in how quickly it mixes down to
the surface.

An area of rain showers is likely (80%) to move through central
Wyoming Saturday morning, so have included -SHRA at
KBPI/KPNA/KLND/KRIW as this area of rain showers moves through. More
convection will develop Saturday afternoon, although it looks more
isolated, so only PROB30 groups at KRKS and KCPR. It will be breezy
at most terminals beginning late Saturday morning.

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...
Air Quality Alert from midnight tonight to 1 PM MDT Sunday for
WYZ001>013.

&&

$$

DISCUSSION...Wittmann
AVIATION...Rowe