Cody, Wyoming 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

233
FXUS65 KRIW 191531
AFDRIW

Area Forecast Discussion
National Weather Service Riverton WY
931 AM MDT Sat Jul 19 2025

.KEY MESSAGES...

- Coverage of showers and thunderstorms increases between 1 PM
  and 2 PM Saturday. These showers and storms continue before
  decreasing quickly between 6 PM and 7 PM. Gusty outflow wind
  of 40 to 55 mph is possible, even with weak showers.

- Less coverage of showers and thunderstorms Sunday with a focus
  over southwest Wyoming. Elevated to near-critical fire
  weather conditions will be widespread as well.

- Drier conditions in place Monday, with chances for afternoon
  and evening showers and thunderstorms Tuesday through
  Thursday.

&&

.DISCUSSION...
Issued at 133 AM MDT Sat Jul 19 2025

Showers will continue to wane this morning, with light showers
lingering over portions of Sweetwater County and finally ending
shortly after sunrise. Another round of showers and thunderstorms
will develop across the area today, starting over western and
central portions by 18Z/19Z. A weak shortwave will be moving over
western portions of the CWA around this time, providing the
necessary lift for initiation. High temperatures in the 80s and 90s
will return this afternoon. Although moisture will be limited with
MLCAPE values of 100-500 J/kg in place across much of the area,
dewpoints will range from the middle 30s into the middle 40s. These
factors will lead to high-based showers and thunderstorms producing
wind gusts of 50 to 55 mph through the afternoon and early evening.
An isolated gust of 60 mph will not be out of the question. There
will be pockets of PWATs around 0.80" across the forecast area
today. However, due to the progressive nature of the storms today
heavy rain is not expected. With that said, there is still a 20%
chance for heavy rain to occur with these storms this afternoon due
to the abnormally high PWATs. Coverage for these showers and
thunderstorms will increase and move eastward through the afternoon,
as the shortwave tracks across the forecast area. Stronger storms
with small hail will be possible over far western portions, where
locally higher CAPE values around 1000 J/kg will be in place.
Convection will quickly end across the area around sunset this
evening, as diabatic heating is lost and the dynamical lift provided
by the shortwave ends as it exits over eastern portions of the
state. Skies will clear through the overnight hours, with mostly
clear skies across central and southern portions by sunrise Sunday
morning.

Drier and warmer conditions return Sunday, with elevated to near
critical fire weather conditions in place for most areas. Critical
RH values, as low as 11 percent, will be widespread across areas
east of the Divide as well as Sweetwater County and portions of
Sublette and Lincoln counties. West to southwest winds, with gusts
of 20 to 25 mph, will also be widespread in the afternoon. Higher
gusts up to 35 mph will occur over the western mountains, especially
across Yellowstone and the Absarokas. A weak shortwave will track
northward over the Uintas, leading to isolated virga showers/dry
thunderstorms over southwestern portions through the afternoon. Wind
gusts around 55 mph will once again be possible.

A closed low will develop over the PACNW from a broad trough over
southern Canada during the day Monday. Heights will increase over
the Cowboy State as a result, as winds aloft turn more
southwesterly. This will lead to a ridge axis to be in place,
extending from a strong high over the Gulf Coast. Hot and dry
conditions, with elevated fire weather conditions occurring once
again. Any precipitation chances look to be very isolated (15% or
less) at this point. Similar conditions will be in place Tuesday.
The aforementioned closed low will fill and lift over MT during the
day Tuesday. Showers and thunderstorms will be possible over
northern portions from the trough extending from the exiting low.
Afternoon showers and thunderstorms will then be possible Wednesday
and Thursday as shortwaves from the Great Basin move northward over
the region.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 457 AM MDT Sat Jul 19 2025

Fog could develop at KPNA and cause MVFR visibilities through
14Z, however, confidence is too low to include in TAF.
Otherwise, VFR flight conditions are anticipated this TAF
period. Light winds increase from the west after 16Z with gusts
generally around 20-25kts at all terminals except KWRL. Gusty
winds decrease between 01Z-03Z.

Isolated to scattered showers and thunderstorms are expected to
develop around 19Z-20Z across Wyoming. However, confidence remains
low (30% chance) in direct impacts to terminals so thunderstorm
chances are reflected in PROB30 groups at all terminals except KCOD.
Thunderstorms could be capable of at least 25-35kt gusty winds.
Shower and thunderstorm chances diminish between 23Z-24Z.

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...LaVoie
AVIATION...Gerhardt