Flights to Florence and Pisa

If you are going to Tuscany (Florence FLR) from Dallas DFW your best option are:
1. Air France via Paris CDG
2. Lufthansa via Frankfurt FRA (the portion from FRA to FLR is operated by Air Dolomiti, which is part of Lufthansa)

Florence FLR may be a better option than Pisa, since Pisa has fewer daily flights to Frankfurt and Air France has stopped flying to Paris from Pisa. Forget about the fog. There is no fog in October in Florence, and winds are a problem only on stormy days. I’ve flown to FLR dozens of times and the only time my flight was affected it was because of mechanical problem. The weather affects Florence primarily in winter, not when you go and even if it does they simply divert you to Pisa.

Air France is a partner of Delta, Lufthansa is a partner of United, in case mileage programs are important to you.

American/British Airways may or may not be a good option to Florence (or Pisa) because I think there is only a daily flight from/to London LHR from/to Florence (same from/to Pisa). If you must fly American/British (they are partners) Bologna is a better option because Bologna has 3/4 flights to London LHR with BA.

Frankfurt in an hour and a half is tight--"doable" but tight. There are often bus transfers from the flights, and it can be maddening.
I have not flown through Heathrow in a while, but I'd also be nervous about that layover time.
I agree, check Florence. Have you checked into Venice and out of Pisa or Florence?
I detest sitting in an airport, but I am looking for longer layovers for the first time in my life, as I often fly Lufthansa and Frankfurt is just a slog.

Whichever airport you have your layover, 1.5 hours is tight. CDG, FRA, LHR are all huge airports, and they often require transferring from terminal to terminal with the people mover train. Two hours min. would be my preference. But since there are multiple flights you can choose from once in Europe, if you miss your connection they will book you on the next flight.

I am thinking since we would like to go to Venice, maybe staying in Bologna the last 2 nights and making a day trip to Venice. We would then be in Bologna the night before we fly out. What should we look for booking to fly out of Bologna? (We would fly into Florence). The tips you have given me so far regarding certain airlines and airports were so helpful!

Also, as I was looking at October to come for a 10 day stay, what would be the latest we should come? Depending on flight prices, we may come late October and come home the first week of November.
Thanks!

What should we look for booking to fly out of Bologna? (We would fly
into Florence).
I don't know what you mean by this question. (I search my flights on Google--"multi-city"--but purchase them directly from the airlines.)
Why not fly into Venice? I have not been yet but I know from many many comments that just doing a day trip is shortchanging yourself.
I would not hesitate to go in early to mid October. Oct 26 is when daylight saving time ends.

How difficult would it be if you are staying in Venice to get to an early morning flight at VCE?
Thanks!

Bologna is certainly an option. There are multiple daily flights from/to Paris CDG (Air France) or Frankfurt (Lufthansa), just like Florence, so you can certainly arrive to Florence then fly out of Bologna (or viceversa), with either Air France or Lufthansa. As I said Bologna has multiple British Airways flights to London LHR as well (Florence only has one BA flight pair from/to LHR, in the middle of the day, but it could still work for arriving to FLR, although not to depart from FLR because you’d get to London too late for any connection to Dallas.

Departing from Venice is certainly possible. VCE is the 3rd most important international airport after Rome and Milan, so you have all options available (British, AirFrance, Lufthansa and more). VCE ha also non stop flight to the US but not to Dallas, only to New York, Atlanta, and Philadelphia, with Delta, United, American. As with all other airports flights to North America depart in the late morning, but if you must catch a North American flight in LHR, CDG, or FRA, you must leave from Italy with an early flight. The issue with Venice airport is that it takes more time to reach from the city center in the middle of the lagoon, since traveling by boat is slow, so an early flight from Venice means getting up at Zero Dark Thirty.

That’s why I said fly INTO Venice—start there, end in Florence, avoiding those early am flights.