lahar

Where I live in the US we have visible disaster plans for lahars[0] because there is a severe lahar risk; most Americans don't even know what a lahar is.

Supposedly the lahar from a major earthquake could wipe out Sea-tac airport and all the communities south of Seattle.

That house isn't designed to withstand a lahar, or the glass doors wouldn't be at ground level.

On this date in 1985 a town in Colombia was wiped out by a lahar from a nearby volcano.

But if it did, and you had a lahar on top of a major earthquake, well, nothing good would happen.

The Sandy River is named as such because of a lahar from a decade prior.

If you live in one of the valleys around Rainier there's a reasonable chance of seeing a lahar in your lifetime.

That could also potentially trigger the lahar that is waiting on Mt Rainier.

The suburbs southeast of Seattle are maybe at risk of lahar flows.

The most recent Lahar on Mt Rainier was in 1947.

I did the lahar hike to the 'now closed off' johnson observatory.

So certainly possible for non-expulsive activities to trigger a lahar and for consequences that sound like they are more from a disaster movie then real life to occur.

We're more worried about earthquakes causing a "lahar" mud slide off Rainier and plowing through lowlands.

It doesn't even mention the expectation of the "big one" triggering a reaction from Mt Rainier, causing a "burp" and a lahar landslide.

As far as lava/ash risk -- generally the biggest risk is from explosive eruptions forming into a fast-moving cloud of ash and mud called a "pyroclastic flow" or "lahar".