With the onset of the thunderstorm season in parched southern Idaho, the clean air is probably gone for the summer. I took the photo below June 9this year. It is of the Lost River Range from Copper Basin.
It is very hazy today in Pocatello, Idaho today due to all the wildfires lightning ignited yesterday. Just got a call from Stanley — very smoky there too. You can check for air clarity by clicking on the web cams I have linked to. I notice today that a number of them show degraded air quality.
The air may not be this clear again until late September. The photo is a medium telephoto.