How are tornadoes formed? Tornadoes come in many shapes and sizes and are often formed during severe thunderstorms, sometimes known as supercell thunderstorms.

Imagine a tornado spinning over an erupting supervolcano. The result would be catastrophic beyond comprehension. While such a ...

Is it right to say that meteorologists still do not know how, exactly, tornadoes form? Yes, believe it or not. Meteorologists still quite don’t understand the mechanism that triggers a tornado.

Landspout tornadoes typically form when a boundary causes air to come together underneath a cloud at the same time that there's some rotation in the lowest part of the sky.

A landspout tornado formed over Chicago's Southwest Side Tuesday afternoon. It was the first tornado to form within city limits since 2006, the National Weather Service said.

A storm scientist explains what’s been driving deadly tornado outbreaks and how tornado season has been changing.