Where I live in California on the northern Coast the air is washed by 6000 miles of Pacific Ocean before it gets here

 So, likely from where I am north along the coast the air is relatively clean and clear most of the year simply because the prevailing winds tend to be from the west heading east across the U.S. So, even during fire season (which now can literally be ANY time of year in Global Climate changes here in California, the majority of the time we don't have smoke here either because it tends to blow east on the winds (most of the time). 

So, because of this it's a nice place to live most of the year with very clear washed air that travels all the way across the Pacific Ocean on the prevailing winds.

The other interesting thing about the Northern California coast is that the fog brings moisture from the ocean to the trees and plants here and keeps them alive whether we get regular rain or not. So, even in a drought year things are still pretty green because of fog off the ocean, especially from about June through August. So, we have our winter in Winter and we sort of have a 2nd winter which can begin as early as April and last until the end of August which isn't usually as cold as the one in Wintertime. So, because of this most people don't have air conditioners because it seldom goes above 80 degrees ANY time of year and it very seldom goes down to freezing more than one day a year here on the coast. And when it does freeze (if it does that year) it would be sometime between Thanksgiving and March usually.