Maybe, it's hard to say, lots of the population lives around SLC and Provo. Provo lies in the middle of a basin, surrounded by huge mountains that create a tra

Maybe, it's hard to say, lots of the population lives around SLC and Provo. Provo lies in the middle of a basin, surrounded by huge mountains that create a trap for smog inversion layers. You'd need data to know, not my anecdata :)