Tokyo lies in the humid subtropical climate zone (Koppen climate classification Cfa), with hot humid summers and generally mild winters with cool spells. Annual rainfall averages 1,380 mm (55 inches), with a wetter summer and a drier winter. Snowfall is sporadic, but does occur almost annually. Tokyo is an example of an urban heat island; the city's population is a significant contributor to its climate. Tokyo has been cited as a "convincing example of the relationship between urban growth and climate". Tokyo also often sees typhoons each year, though few are strong. The last one to hit was Fitow in 2007.

Tokyo was hit by powerful earthquakes in 1703, 1782, 1812, 1855 and 1923. The 1923 earthquake, with an estimated magnitude of 8.3, killed 142,000 people.