Visitor numbers peak between May and September, as do hotels rates. It is for a good reason: at this time of year, you can expect the same pleasant sunshine and mild temperatures enjoyed by Renaissance artists. The warm weather will also likely inspire you to savor many deliciously refreshing gelato. April is an interesting time to travel, as temperatures are on the rise and hotels rates are still adjusting from the colder months. Just be mindful to avoid school holidays, unless you are travelling with children, in which case it could be a perfect time. Winter is not as cold as most northern European cities, so Florence gets a lot quieter and hotel rates reflect this.