Kerama islands are located in the east of Eurasian Continent, north of northern circle, being influenced by the Japan Current and monsoons. The temperature in Kerama islands are more than 10 ºC higher than that of the mainland, Japan and the average temperature in a month is from 21.5 ºC to 23.8 ºC. Summer lasts longer than winter and there are few differences between seasons. The rainy season in Keramas starts anytime from May to June, which is one month earlier than that of main land, Japan. The rainy season in Keramas lasts around 30 to 60 nights. The days when temperature reads over 25 ºC are called tropical night and the days when it read over 30 ºC are called sweltering day. The temperature stays high even at night and it is humid. The days from the end of June to August are mostly tropical night and sweltering day. Typhoons come during July and October and seven or eight of the tropical depressions with maximum wind speeds of 17m/s moving from south east up to Keramas.
Climate 25% of the annual rainfall in Kerama islands are brought by typhoons. Because the rain fall is unstable during rainy season, drought sometimes occurs. When drought last long, a good deal of damage is done to the crops because the land are made up of the Ryukyu lime stone. Three months during December and February are the high season of winter monsoon. Because high pressure from the Continent comes down to Keramas, northern wind comes with coldness. As the wind go through over Japan Current, they receive moisture from the sea and rain continues over a few days. Although rainy days often come, they do not bring much rain.