Italy’s climate is mild and temperate, though there are more extreme fluctuations in the mountainous regions and coastal areas. Northern Italy is warm in the summer, central Italy is humid and southern Italy is very dry and hot. In the winter, the north is cold and damp, the central part of the country can reach near freezing temperatures and the south is generally fairly warm. Coastal temperatures are largely the same throughout the country and there is greater change in seasons as you climb higher into the mountains. The Italian Alps frequently experience snow squalls as early as September.
Peak and off peak seasons for flights to Italy depend largely on where you want to go. On the coast, expect the largest crowds between June and September, while mountain ski resorts are bustling from December through to April. The inland cities are busiest between April and October, despite the uncomfortable heat and humidity of mid-summer. Venice is a popular destination during the Carnival celebrations in February or March, so if you want to stay away from crowds and enjoy the best weather, the ideal times to book flights to Italy are between April and May or September and October.
Typically, the Italian off-season lasts from early November to the middle of December and then again from Christmas to the end of March. During the winter, most major attractions limit their hours or shut down for annual renovations. This can be a great chance to book cheap flights to Italy and obtain deep discounts on hotel accommodation.