Best places to visit between Florence and Rome in February?

I loved Orvieto but don't know that it is a few days city. Verona, Vicenza, Padua are all lovely.0

How many. nights do you have before heading to Rome, 5 or 7?
Consider visiting Siena & Orvieto.
If you have more time, also consider visiting Assisi after Orvieto.
All these places are easily reachable by public transportation. You’d take the bus from Florence to Siena, then a train to Orvieto, then train to Assisi, and finally a train to Rome,

Enjoy your time in beautiful Italy!

Weather is more dependent on luck than on geography. In February I don't think there's likely to be much difference. Venice can be cold and windy or warm and sunny (i've been several times in February and had both - though more sun than rain). Because of its topography, Florence can be quite cold in winter. I wonder if Orvieto is a good choice - there's a lot of up and down which can be difficult in wet weather and a hill town might get a lot of gusty wind, also don't expect beautiful views when the trees and vines are bare.

You might find Bologna to be a good alternative. While it's low key and doesn't have great sights, it does have a few worth visiting and the historic center is charming. And it is lined with porticos offering great protection from the rain. You can day trip to a lot of other towns by train that are not hill towns but have lots to offer. If you choose Bologna, it would obviously be between Venice and Florence.

Tuscany/Umbria are not at their best in February as the vineyards and trees are bare of leaves and it’s all a bit dreary. Visiting a city or two would probably be more pleasant at that time of the year - Bologna, Padua, Ravenna, or head south to Naples where it is likely to be a bit warmer.

Although I'm a big fan of Bologna, Padua and Ravenna, they are not (geographically) between Florence and Rome.

Orvieto has a surprising number of interesting sights for a place of its size; I could keep myself busy there for two full day (three nights), ideally in reasonably good weather--though there are some good museums available for bad weather conditions. I found Orvieto quite a pleasant place just for wandering around, bit I imagine it could be pretty busy with local (Roman) tourists on a nice weekend in February.

If you haven't been to Siena, it's another possibility, as are Arezzo and Perugia. I haven't checked travel times to those places. Florence to Rome is very fast by Freccia train. A stop in one of the smaller towns will add significantly to your travel time.

You could also go from Florence down to Naples before heading back up to Rome. However, you'd have to be selective in your sightseeing with only 2 or 3 days in Naples.

Orvieto or Perugia/Assisi