YOU MUST HAVE A VALID PASSPORT!
Closest airport: Florence, Italy (FLR)
You can also fly into Rome (FCO) and take a train to Florence.
If you have a layover in a different country, be prepared to go through customs.
This will take about 20 minutes to 1 hour depending on how busy it is.
Average High Temperatures in mid-May: low to mid 70s
Average Low temperatures in mid-May: low 50s
The electrical outlets in Italy and throughout Europe are different than in the U.S. Bring a voltage converter. Here is one on Amazon.
Bring some Euros (currency) ahead of time if you can. ATM's will charge a fee to withdraw cash and some places may not take credit (but most do).