Tornado Hits Town of Aumsville Oregon : watch video

A tornado that caused substantial damage in Aumsville late Tuesday morning likely was caused by unstable cold air slamming into the unseasonable warm, moist air mass that has lingered in the Willamette Valley for several days, climate experts said.

Tornadoes in Oregon are unusual, though not exactly rare. “Oregon’s moderate climate and topography are not conducive to frequent powerful tornadoes,” explained Kathie Dello, a research scientist with the Oregon Climate Service at Oregon State University. “The Pacific Ocean moderates the climate and the Coast Range protects us.”


A tornado ripped through Aumsville, Oregon just before noon today. A tornado warning was in effect for Marion and Clackamas Counties until about 12:30PM. The National Weather Service lists recent tornadoes in Oregon, including a December 2008, F2 tornado near Newberg described as “the most powerful tornado in Oregon in many years.” We had a lot of warm, moist air that had settled in the valley beneath a cold pool of air aloft, and a very strong low-pressure system that created a wind shear. Aumsville Oregon.