the first half of summer is tsuyu, or the rainy
season, in Japan. It is caused by a collision that
arises between two different air masses of the same
strength, that is, a cold northerly mass and warm
southerly mass. The crash forms a stationary front
that moves slowly between the south and north. This
stationary front makes the cloud cause rain that
lasts long. It finishes by late June in Okinawa and
usually ends in Shimane by the middle part of July.
As the rainy season ends, full summer begins. The
summer is sweltering and humid, but green leaves
around are so beautiful.