Late June or Early Aug?

Hello! We are planning our family vacation to Banff this summer. Want to ask for this group’s collective wisdom, whether going in late June/July 4th week would have substantially better chance to avoid wildfires/smokes? My husband prefers that time frame for wildfires concerns, i prefer early august instead. What’s the pros and cons? So far i know flights are more $$ around the July 4th holiday weekend/week.