January is generally cold, with the freezing tramontana wind sweeping down from the north. January 29, 30 and 31 are supposed to be the coldest of the year.
A winter vacation has some advantages, however: once the Christmas holidays are over (after January 6), the sights are almost deserted and you will find a warm welcome everywhere. In our holiday homes, low season is synonymous of very low prices.
Italians say that February is "corto e maledetto" - short and accursed. It can be almost as cold as January.