佛罗伦萨 can be extremely hot and humid in july because it's in

because it's in a small basin encircled by hills.  We visited Tuscany in summer for 6 weeks back in 2010's and the hottest days were reaching 40C so we spent a lot of time in the pool.  July is also expensive and VERY crowded in Florence.  you get far better experience visiting this beautiful city in April-June Sept Oct.