Moderate Climate

As part of the Willamette Valley, Wilsonville is within the marine west coast climate zone. Summers are generally warm, but temperatures year-round are moderated by a marine influence from the Pacific Ocean. Wilsonville receives most of its precipitation during the mild to cool winter months, with the wettest period from November through March. July and August are the warmest months with an average high temperature of 80°F, while December is the coolest month with an average low of 33 F. On average, December is also the wettest month with 6.75 inches of precipitation.