THE WEATHER FACTOR

Five different climatic zones exist within the Japanese archipelago:

• the subtropical zone, including the Ryukyu and Ogasawara islands groups (resulting in the Nansei Islands climate);
•  the warm-temperature zone of broad-leaved evergreen forests, which covers the greater part of southern Honshu, Shikoku, and Kyushu (the Sea of Japan climate);
•  the cool temperature zone of broad-leaved deciduous forests, which covers central and northern Honshu and the south-eastern part of Hokkaido (the Pacific Ocean Coast climate);
•  the subalpine zone, which includes central and northern Hokkaido (the Hokkaido climate);
•  the alpine zone in the highlands of central Honshu and the central portion of Hokkaido (the Alps climate). 

  The 5 zones notwithstanding, Japan has four distinct seasons except for the southernmost islands and is thus classed as a northern temperate country.

Whatever the Weather… The climate can be surprising depending on where you live in Japan.  Since Japan spans a distance of 3,500 km from north to south, between the northern latitudes 45 and 20 degrees, people living in the different regions of Japan would experience different types of climate. If you lived at the southern or southwestern ends of Japan, for example, the weather is subtropical in Kyushu or Okinawa where it is always warm with an average temperature of over 22 degrees Celsius throughout the year. 

If you lived in Hokkaido, you would experience snow four, or even five months out of twelve in a year. Much of Hokkaido has a sub-arctic weather pattern and ice floes are commonly seen on the northern coasts facing the Sea of Okhotsk. The cold Siberian winds from the north pick up moisture crossing the Sea of Japan which then fall as rain and snow when encountering the Central Alps and other mountain barriers which run along the center of Japan.   

 

 

Most places in northwestern Honshu facing the Sea of Japan are snowy regions as well. The heaviest snows are in Nagano Prefecture where 8 to 10 m can be common. Japan has more than 300 ski resorts, and one of the snowiest regions in the world. 

The climate of Japan is thus influenced by the country’s location on the edge of the Pacific Ocean, its closeness to Asian continent and to the mountain ranges that run through the spine of the islands.    

Japan is the wettest temperate country in the world. Some places in Japan, eg. Kii peninsula experience as much rainfall as 4,002 mm while the average annual precipitation measures 1,700 mm, about twice the worldwide average. 

Find out more in other weather pages: What is “kosa” or yellow sand?