What are lahars?

A lahar is like a fast-moving river made of mud and rocks that comes down from a mountain during or after a volcano erupts.

Imagine you're playing with a big pile of dirt, sand, and pebbles in your sandbox. Then someone shakes the sandbox really hard, all the stuff inside starts to flow out like a wave. That’s kind of what happens with a lahar.

A lahar happens when water mixes with volcanic ash, dirt, and rocks on a volcano's slope. This mix can be from rain, melting snow, or even the volcano itself erupting.

It moves really fast, like a river that’s also full of rocks and boulders, and it can sweep everything in its path away, including houses, trees, and even people.

If you've ever been caught in a sudden flood in your neighborhood, you know how powerful water can be. A lahar is like that, but much bigger and messier, it feels like being pushed by a wall of wet mud and rocks all at once!