What is that awful sound? Could it be a huge train barreling down the mountain?

Watch out—it’s a MUDSLIDE!

The mud-river roars. It looks like a big, brown snake slithering across Mount Shasta, the four-foot-deep water carrying boulders with it.

But where did the water come from? California has had a three-year drought, so we can’t blame this muddy mess on the rain. Scientists think it came from a chunk of underground ice called a glacier.

Three years of hot sun may have made part of the glacier melt—then, pop! Water surged out like a bottle had been uncorked.

Nobody has been hurt by this mudslide, though some roads are in a big mess. Will cold winter weather make the glacier freeze again? Time will tell.