A mudflow that recently burst through the banks of a volcanic lake in New Zealand gave scientists an up-close and personal view of the freak event and a chance to test their disaster warning systems.

In the shadow of Washington State’s Mount Rainier, about 90,000 people live in the path of a potential large lahar—a destructive, fluid and fast-moving debris flow associated with volcanic slopes. At ...

An outpouring of magma isn’t the biggest risk to people downhill from Mount Rainier. The active volcano’s greatest danger comes from lahars — amalgams of mud, rock and water that are as dense as wet ...

TROUT LAKE — As Pat Arnold plucked weeds from her yard with a view of snow-capped Mount Adams, she navigated around large boulders that hint at the volcano’s destructive past. Over the course of ...

Mount Rainier National Park will hold a virtual public meeting in June so people can learn more about the proposed expansion of a system that monitors and provides alerts of volcanic mudflows. The U.S ...