In early summer, most part of Japan get visited by
the rainy season caused by collision of cold
northerly air mass and warm southerly mass which
stay long. The rainy season usually lasts from the
beginning of June until mid July. It does not rain
every day. How often and how heavily it rains
depends on year.
As the rainy season ends, full summer begins. Both
temperature and humidity rise considerably. Fewer
plants are seen in flower in lowland area.