If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Naha: 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 19°C. The rainiest months in Naha are June, May, August and October, with each month seeing an average of 294 mm of rainfall.