Supercells are the mightiest of the thunderstorms. They can roll for hours while maintaining tornadoes and damaging hail.

The same storm produced baseball-sized hail. The rotating thunderstorm churned over entirely empty prairie lands.

Prior to severe thunderstorms in Cumberland and Sampson counties Sunday evening, some of you saw a unique cloud formation. Mammatus clouds will sometimes form within the anvil of a thunderstorm.

Spring storms bring severe weather threats to West Texas, with tornado warnings issued and potential for hail and strong ...

LA PLATA, Md. — On a Sunday evening in late April 2002, a deadly supercell storm tore across the DMV, killing five people and causing millions of dollars worth of damage. Twenty-three years ago ...

A supercell thunderstorm, which brought almost hurricane-force straight-line winds, was responsible for a 300-mile swath of damage across northern Maryland and southern Pennsylvania on Saturday ...

A stock image of a supercell thunderstorm in Michigan. A stock image of a supercell thunderstorm in Michigan. Meindert van der Haven/Getty "Prepare immediately for large hail and damaging winds ...

Multiple tornadoes were reported Thursday evening from two supercell thunderstorms that traveled from Nebraska into Iowa. At least six reports came from southwest Iowa, although the National ...

High temperatures, humidity and an approaching cold front are expected to brew up some of the most severe thunderstorms seen in the province so far this year on Tuesday afternoon, according to ...