A supercell storm along the Mason-Dixon Line brought nearly hurricane-force winds through northern Maryland and southern PA ...

Tornadoes are primarily produced in two different ways: From supercell thunderstorms and from non-supercell thunderstorms. A supercell tornado is produced from a supercell thunderstorm.

Landspout tornadoes are usually weaker than supercell tornadoes, according to the government agency, and can be whipped up by relatively benign conditions, but they can still topple trees ...