We will be traveling to Venice, Rome and Florence in mid February. Any tips on weather expectations?
It can vary quite a bit. Google for what is has been like the past few years. It seems like when I head to Florence in February it rains but I might just be unlucky.
Aside from this year's crazy weather - which looks like only a forerunner of next year . . ..
I've had lots of warm-ish, sunny days in all 3 cities in February, on multiple trips. Florence tends to be the coldest, due to its topography. I've also had snow in Rome (it was fabulous - snowed overnight, the next day was sunny, wonderful photos). I like to take a sturdy rain poncho which keeps my camera and backpack dry and both hands free. I also take a spare pair of shoes just in case mine don't dry out overnight - hasn't happened yet, but my feet seem to like different shoes after 2-3 days. Most important for me are the shearling gloves I bought in Florence which keep my hands warm and dry (though after they get wet a few times, they aren't as pretty) and are soft and pliable enough that I can use my camera while wearing them.