Frequency of 400 mm or more rainfall per day Japan 2014-2023
In 2023, precipitation of 400 millimeters or more per day occurred 28 times in Japan. Within the past decade, this figure peaked at 47 days in 2019.
Most of the rainfall in Japan occurs during the rainy season, which lasts from early June to mid-July. Heavy rain is often caused by typhoons, which develop over the Pacific Ocean and regularly approach the archipelago between July and October.