Weather is probably a major factor when you plan your trip to Oshima-gun Amagi-cho, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July, with an average temperature of 28°C, while the coldest months are January and February, with an average of 17°C. The rainiest months in Oshima-gun Amagi-cho are June, May, July and August, with each month seeing an average of 307 mm of rainfall.