If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Cle Elum: The hottest months are usually July and August, with an average temperature of 16°C, while the coldest months are December and January, with an average of -3°C. The snowiest months in Cle Elum are January, December, February and March, with each month seeing an average of 17 cm of snowfall.