The Columbian reported that a U.S. Geological Survey report said such quakes are common in areas around Mount St. Helens and Oregon's Mount Hood.
The latest southwest Washington quakes included a 3.7 magnitude jolt at about 2:30 p.m. Friday, followed by a 3.4 and a 3.1, both on Friday evening.
The quakes occurred at a depth of about 8 miles. There were no reports of damage.
The USGS said volcano-related seismic activity was at normal background levels.
More Northwest Headlines
Sheriff: Port Orchard man stabbed when he asked for money back after sex 'It's only Aug. 24': Fires expected to burn for months Seattle teachers vote to continue bargaining Oregon: mobile pot cart illegal 2nd deer shot by poacher in Bellingham city limits Bellingham man dies after Alaska bridge jump NRA sues over Seattle’s adoption of ‘gun violence tax’ Fishing gear theft leads to high-speed chase, van fire in Port Orchard
Our new comment system is not supported in IE 7. Please upgrade your browser here.