Contrary to popular belief, it does get kinda cold in Phoenix. But "cold" is relative to each individual, as our brethren to the east can surely attest to. Having lived in AZ for several years (prior to the smoking ban), I'd have to say that most establishments are inclined to dealing with hot weather as opposed to cold..............i.e. covered patio/bars with misting coolers. So I don't think that it's the heat that affects business as much as colder weather does . Go figure.