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(East Asian) rainy season (in Japan, usu. from early June to mid-July)
rain during the rainy season
今年の黴雨は例年より長く続いている。
This year's rainy season is lasting longer than usual.
黴雨が明けたらすぐに夏が始まるだろう。
Summer will probably start as soon as the rainy season ends.
黴雨の時期は洗濯に困る。
Doing laundry is hard during the rainy season.