085 

FXUS65 KRIW 050852

AFDRIW



Area Forecast Discussion

National Weather Service Riverton WY

252 AM MDT Fri Jun 5 2026



.KEY MESSAGES...



- Very warm Friday and Saturday as ridging builds across the

  Rockies. Highs today reach the 80s, with a few low 90s in the

  Bighorn Basin. Temperatures will be even warmer Saturday, 

  with highs in 80s and 90s, with a few 100 degree readings 

  possible.



- Dry and windy conditions today and tomorrow will lead to

  elevated to near-critical fire weather concerns across the

  state.



- Ridge shifts east next week, bringing better moisture into

  western mountains. Afternoon showers and thunderstorms are

  expected over higher terrain.



&&



.DISCUSSION...

Issued at 224 AM MDT Fri Jun 5 2026



The trough that has been lingering in the vicinity that past

couple days is finally moving to the east, which will open the

door for the next system to impact the NW Rockies. This system

is just starting to drop down the West Coast, and will 

gradually buckle a ridge ahead of it across the Rockies during 

the next 48 hours. Today will start with flat ridging, with 

nearly clear skies and temperatures in the 70s and 80s. West

winds will be lighter than yesterday, but a few gusts near 20

mph are possible across the usual areas of central WY.



The ridge then starts to build in the vicinity tonight into

Saturday, with increasing temperatures aloft. Still noting H7 

temps of 16 to 19C, which translates to mid to upper 80s west of

the Divide and into the 90s to the east. There remains an 

outside chance of triple digit readings, mainly on the open 

ranges of Johnson County and the lowest elevations of the 

Bighorn Basin. The placement of the ridge is centered on the 

Central Plains, so a weak impulse may nudge into the NW WY Parks

during the afternoon, bringing some cloud cover and a shower or

two, and will hold temps there down in the 70s. 



Saturday will also see increasing southwest winds ahead of the

next system. Widespread gusts of 30 to 40 mph are expected

across the state. This southwest flow will also be modified

desert air, so humidity levels will be falling to 5 to 10

percent across a wide swath of the state. These will result in a

near-critical fire weather day across the state. 



The ridge shifts to the east Saturday night, shifting the

moisture tap from the southwest across a larger part of western

WY. The first piece of the western trough races across the

state, bringing a good chance for showers and thunderstorms. 

The southwest flow will continue into the middle of next week, 

which is setting up as a pattern where daytime heating sparks 

showers and thunderstorms along the highest terrain in the 

afternoon, dissipating each evening.



&&



.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...

Issued at 1031 PM MDT Thu Jun 4 2026



Mostly SKC skies currently in place this evening. The lower

clouds that were expected at KCPR dispersed earlier as the cold

front reach the Divide around 03Z. The cold front will reach  

KRIW shortly after the start of the forecast, washing out after

sunrise. Conditions will remain dry through the TAF period. 

Most terminals will have wind gusts around 20kt by 17Z, becoming

light (10kt or less) again by 02Z.





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...

None.



&&



$$



DISCUSSION...Straub

AVIATION...LaVoie