In Japan, there's a custom observed in June known as koromogae that involves the changing of school uniforms and work clothes to accompany the change of the seasons. Said to have begun as an event in the imperial court during the Heian Era (794-1185), this custom could be considered characteristic of Japan, where life is so closely attuned to the seasons.

Koromogae generally refers to the switch from winter to summer clothes on June 1, but also applies to the change from summer to winter clothes on October 1. The simultaneous change to fresh summer wear at the start of June among students and company employees who were dressed for winter until the day before is a familiar sight for Japanese people, giving them the sense that summer is beginning.