Amami Oshima’s Climate
Seasonal monsoons and the warm waters of the Kuroshio current give Amami Oshima a subtropical oceanic climate. The island is warm and humid year-round, with many rainy days. The average temperature is around 21°C, and the annual rainfall can reach up to 3,000 millimeters. Even in the winter months of January and February, the temperature rarely drops below 10°C. March and April are warmer and often rainy, but the true monsoon season begins in May and runs until the end of June. The summer months are hot and sunny, and most islanders prefer to stay indoors during the peak daylight hours.
Typhoon Alley
Like most of Japan’s southern islands, Amami Oshima is located on the northbound route of tropical storms that form in the mid Pacific. From midsummer through fall, it is frequently hit by the strong winds and heavy rainfall of the worst of these storms, which become typhoons. While these can damage the island’s communities and infrastructure, they also ensure a consistent water supply throughout the year, and support the island’s lush foliage. The people of Amami Oshima are used to typhoon-related hardships, such as transportation delays and shortages of imported goods and services, but empty store shelves may catch visitors by surprise.