3.1 Climate
Japan is a temperate region with four distinct seasons, but because of its great length from north to south, its climate varies from region to region: the far north is very cold in the winter, while the far south is subtropical. The climate is also affected by the seasonal winds blown from the continent to the ocean in winters and vice versa in summers.
Late June and early July are a rainy season (except in Hokkaido), as a seasonal rain front or baiu zensen (梅雨前線) stays above Japan. In the late summer and early autumn, typhoons develop from tropical depressions generated near the equator, and track from the southwest to the northeast, often bringing heavy rain.
Japan's varied geographical features divide it into six principal climatic zones.
- Hokkaido: Hokkaido has a temperate climate with long, cold winters and cool summers. Precipitation is not heavy, but the islands usually develop deep snowbanks in the winter.
- Sea of Japan: The northwest wind in the wintertime brings heavy snowfall. In summers, the region is cooler than the Pacific area, but it sometimes experiences extremely hot temperatures due to the Foehn wind phenomenon.
- Central Highlands ( Chuo-kochi): A typical inland climate, with large temperature differences between summers and winters and between days and nights. Precipitation is light.
- Seto Inland Sea (Seto-naikai): The mountains of the Chugoku and Shikoku regions block the seasonal winds, bringing mild weather throughout the year.
- Pacific Ocean: Experiences cold winters with little snowfall and hot, humid summers due to the southeast seasonal wind.
- Nansei-shoto ( Ryukyu) or Southwest Islands: Has a subtropical climate with warm winters and hot summers. Precipitation is very heavy, especially during the rainy season. Typhoons are common; in 2004 a record number of 10 typhoons reached the main islands.
3.2 Prefectures and regions
The Local Government Law of Japan divides the country into 47 prefectures, which carry out administrative duties independently of the central government. From north to south (as listed in ISO 3166-2), these are:
Japan is also commonly divided into nine regions. From north to south, these are Hokkaido, Tohoku region, Kanto region, Chubu region, Kinki region (commonly called Kansai), Chugoku region, Shikoku, Kyushu, and the Ryukyu Islands.
