If you’re hoping to get lost in the rain on your romantic getaway, check out these details about year-round temperatures in Gangneung: The hottest months are usually August and July with an average temp of 71°F, while the coldest months are January and February with an average of 34°F. The rainiest months in Gangneung are August, July, September, and June, with each month seeing an average of 8 inches of rainfall.