http://www.newsweek.com/heavy-rainfall-climate-change-increase-volcano-danger-mount-st-helens-1727992

Heavy rainfall, which is expected to increase in certain areas in the future, can make the damage caused by volcanic eruptions worse.

According to research published in the journal Royal Society Open Science, climate change-induced rainfall increases will exacerbate volcanic hazards including dome explosions and flank collapses, potentially endangering a larger number of people living in the vicinity of volcanoes worldwide, including Mount St. Helens.