I get conflicting thoughts on this... we have the chance to use some points to fly to Europe (from Canada) at the end of August. We'll go to Paris but were thinking about adding Rome as a second city... only we've had several people tell us it's unbearably hot. Should we avoid it? Or only go for a couple of days?
I guess a lot depends on what you consider "unbearably hot." As for the issue of many things being closed, you will have encountered far more closures in Paris in August, so you will be accustomed to it by the time you get to Rome.