Taking the local weather in Ketchikan into account is an important factor for planning your visit, especially if you plan to spend your trip by the pool. The hottest months are usually July and August, with an average temperature of 13°C, while the coldest months are February and December, with an average of 2°C. The rainiest months in Ketchikan are November, January, October and September, with each month seeing an average of 395 mm of rainfall.