Temperatures in Venice are much more moderate than in Florence or Rome. But personal experience tells me that when it's moderately hot in Venice, you swelter. It's the humidity; Venice is classified as having a Humid subtropical climate. There are between 6.5 and 9 precipitation days in most months, the exception being August, with fewer than two precipitation days.
Unlike the other cities of Italy's "Big Three," Venice's rainfall is pretty well distributed throughout the year, totalling just over 32 inches on average. You'll find thunderstorms, particularly in Spring and Autumn. The biggest holiday periods in Venice feature its worst weather: Christmas (wet and cold), Carnevale in early Spring (foggy and cold), and Venice Film Festival time in August (hot and humid).
The historic climate charts below tell the story of Venice Weather.
Venice: Best Time to Visit
The best times of the year to visit Venice are from May through early June, then September and October.
Venice's high water, or Acqua Alta, generally occurs in spring or fall. November seems to be the worst time for high water, which peaked at high levels in that month in 1996 as well as 2012. Today, over 60 occurrances of high water are expected each year.
Venice has a system of warnings for residents and visitors, and inexpensive rubber boots are available for sale or are given out by hotels to guests when acqua alta occurs. For more, see: Acqua Alta in Venice.
Venice is one of the best walking cities in the universe. As a sea power, the wealth of ideas it brought back from its excursions, especially to the east, resulted in a city whose art and arcitecture is unique, interesting, and diverse. Wander the city, get away from Piazza San Marco and the tourists and squeeze through the narrow passageways for a day. Then, when you want it all explained to you, take a tour. We prefer the scholarly tours put on by Context Travel, where you can find out about Byzantine or Medieval Venice, or find out how the Plague influenced life in Venice, or simply explore a Venice neighborhood of your choosing. See: Context Travel Venice Tours.
It takes a lot of exploring to put Venice in perspective. You might want to stay in a vacation apartment or house, expecially if it has an altana, a typical Venetian rooftop terrace, great for when the weather is warm and you want a view over the city and lagoon: Venice Vacation Rentals.
Escaping the tourist hordes? Perhaps you'd rather stay at the beach: Venice Lido.
Venice Travel Information
More information on planning your vacation to Venice, Italy.
Venice Airport Hotels (Marco Polo Airport VCE)