Weather in Tokyo varies greatly. If you visit, you will be spending a lot of time walking from subway stations to your destinations, so plan accordingly.
Tokyo winters are dry, with maybe one or two light snowfalls a year. Temperatures in January usually range from 32 to 48 degrees Fahrenheit, but the wind can make it seem colder. Bring a heavy coat.
Around the beginning of April, cherry trees start blooming. To enjoy the white-pink bursts of petals, people have picnics in parks or even go on tours. Temperatures in April usually range from 48 to 67 degrees Fahrenheit. A light jacket should be the only extra clothing necessary.
In June and July, rain pummels Tokyo. Be sure to pick up an umbrella from a convenience store or 100-yen shop.
July and August are the worst months to visit Tokyo. The city is hot and steamy, and the packed subway cars are unbearable. Temperatures in July usually range from 72 to 86 degrees Fahrenheit.
Around October, Tokyo returns to pleasant weather. As in spring, people like to go tree-viewing, this time for fall leaves (called koyo). Temperatures in October usually range from 55 to 72 degrees Fahrenheit. Again, a light jacket is all you need.