Before the summer starts in Japan, there is a rainy season called 梅雨/つゆ/Tsuyu. It is also read as ばいう/Baiu. 梅雨(Tsuyu) starts at the beginning of May in Okinawa, which is the southernmost tip of Japan. 梅雨前線/ばいうぜんせん/Baiu zensen, which is weather front that causes rainy season in Japan, slowly moves up from Okinawa to the North of Japan. The main island of Japan enters the rainy season at the beginning of June. North end of Japan, Hokkaido rarely experiences rainy season. The rainy season continues for about a month to a month and a half. In Okinawa, 梅雨(Tsuyu) ends at the end of June but other places experience it until mid-July.
梅雨(Tsuyu) is written Plum Rain in Kanji. It is said that the name came from the fact that the rainy season starts around the time when plum fruits start to ripe. Another explanation is that it derived from 黴雨/ばいう/Baiu, 黴 means moulds because this time of the year has high humidity that causes mould to grow. And it changed to 梅雨 which has the same reading.
During 梅雨 (Tsuyu), it rains frequently and humidity is high, and everything feels sticky. This is not only uncomfortable, but it is easier for things to get mouldy. Unlike typhoons, there is no strong wind. During the rainy season, the Kushu region experience a quarter of the total annual precipitation and the Kanto region experiences a fifth of annual precipitation.
During the rainy season, people often visit places that look beautiful in wet weather. For example, Kamakura, a Japanese traditional town in Kanagawa prefecture, is famous for hydrangeas. Flowers of hydrangeas look magnificent in the rain. Kamakura is one hour by train from Tokyo, so many people decide to visit there for a short trip. But if you want to avoid rain, it would be best to visit Hokkaido because there is no rainy season.
There are many countries that experience the rainy season but it differs slightly. For example, Thailand has a rainy season that lasts more than a month and during the rainy season, there is a lot of sudden showers. There are such differences so it might be interesting to compare them.
Once the rainy season is over, Japan enters the hot summer season with more sunny days and higher temperatures than before the rainy season.
Example sentences that have 梅雨(Tsuyu)
6gatsu ni hairu to sorosoro tsuyu iri da
It's June and the rainy season is about to begin.
Tsuyu wa sentakumono ga kawakinikui
It's hard to dry clothes in the rainy season.
Tsuyu ga owattanode seiten no hi ga hueta.
The rainy season is over and we have more sunny days.