Taking into account the local weather in South Cle Elum can help you maximize your time at the pool during your trip. The hottest months are usually July and August with an average temp of 60°F, while the coldest months are December and January with an average of 27°F. The snowiest months in South Cle Elum are January, December, February, and March, with each month seeing an average of 7 inches of snowfall.