Japan’s Meteorological Agency announced today the official arrival of the annual rainy season started on June 14 for the Tokai Region, which encompasses Aichi, Gifu, Mie and Shizuoka Prefectures.
The agency noted that this year’s start is eight days later than the average start date, and is even one day later than last year’s starting date. The rainy season tends to end around July 19 coinciding with the national holiday Marine Day.
According to the Ministry of Land, Infrastructure, Transport and Tourism, the rainy season is a phenomenon seen only in East Asia, and is caused by the formation of a stagnant weather front called the “rainy season front.” This front stretches from east to west between the North Pacific High Pressure point (Ogasawara air mass) in the south and the Okhotsk Sea High (Okhotsk air mass) in the north. Toward the end of the rainy season, torrential rains sometimes occur in western Japan causing flooding and mudslides.