Weather Words: Frost Quake

Some of you may have experienced an earthquake, but what about a frost quake?

A frost quake, also called a cryoseism, is a rare weather phenomenon that occurs during extremely cold winter conditions. It’s not a true earthquake, but it can sound and feel like one.

Frost quakes happen when water trapped in the ground freezes and rapidly expands. This sudden expansion puts enormous pressure on the surrounding soil and rocks.

When the frozen water cracks the earth, it releases energy in the form of a sharp, booming sound and sometimes even ground vibrations.

Frost quakes tend to occur during the coldest nights of the year, particularly after a thaw when water has seeped into the ground and then freezes again. Homeowners sometimes report rattling windows, shaking walls or even cracks in driveways, making frost quakes a startling, if harmless, winter spectacle.

Scientists continue to study frost quakes to understand the exact mechanics and predict when they might occur. While they are startling, frost quakes typically do not cause extensive damage like earthquakes — they’re essentially nature’s way of letting off a little winter pressure.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.