Active volcanoes dominate the skyline in many parts of the Pacific Northwest.
Many of these volcanoes have erupted in the recent past and will erupt again in the foreseeable future. The time between eruptions is usually measured in decades or centuries, so eruptions are not a part of our everyday experience. However, in 1980 Mount St. Helens vividly demonstrated the power that Cascade volcanoes can unleash when they do erupt .