Weather is probably a major factor when you plan your trip to Taegangjin, and keep 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 temp of 72°F, while the coldest months are January and February with an average of 34°F. The rainiest months in Taegangjin are July, August, September, and June, with each month seeing an average of 9 inches of rainfall.