Dates of Rainy SeasonThe Japanese word for rainy season is tsuyu (梅雨) ~ literally "plum rain". The rainy season coincides with the ripening of plums in Japan. The exact dates vary by year and location.
|Okinawa||early May ~ late June|
|Kyushu||late May ~ mid July|
|Shikoku||early June ~ mid July|
|Osaka, Kyoto, Kobe||early June ~ mid July|
|Tokyo, Yokohama, Chiba||early June ~ late July|
|Tohoku||mid June ~ end of July|
|Hokkaido||no rainy season|
Japan's Meteorological Agency calls the start and end of the season each year. It's a great relief to everyone when it's over.
What to ExpectRainy season happens when cold air from the North and warm air from the South converge in the late spring and early summer. The primary effect is reliably cloudy weather.
The rain isn't all that bad during rainy season. For example, Tokyo gets more rain in September than in the rainy season months (June 167.7 mm, September 209.9 mm). However, there are far more sunlight hours in September than in June or July.
Nevertheless, it does rain a great deal in rainy season. It also feels as if it's always cloudy and gray.
Travel During Rainy SeasonThere's no bad time to visit Japan. Generally, Japanese school kids are still in school during rainy season — that means that prices are reasonable and attractions aren't too crowded.
August is incredibly hot and humid in Japan. Prices shoot up dramatically in August due to school and Obon holidays.
If you don't mind carrying an umbrella — you may save a great deal of money by traveling during rainy season. It depends on your personal tastes — some people enjoy activities such as onsen in the rain.
Other Bad WeatherKeep in mind that Japan's typhoon season is May - October. Typhoons are most likely to strike in August and September.
On average 3 typhoons hit Japan directly and 11 strongly affect Japanese weather each year.