Mount St. Helens, Washington simplified hazards map
Mount St. Helens, Washington simplified hazards map showing potential impact area for ground-based hazards during a volcanic event. Mauve indicates areas at risk from lava flows and avalanches of hot rock and gases call pyroclastic flows. Bright red areas that fads to orange and yellow indicate potential routes for lahars (volcanic mudflows)? Not shown are areas subject to hazards from volcanic ash. Volcanic ashfall is often a nuisance but can be a more serious hazard during large explosive eruptions.