A "dynamic" weather system sparked a "historic" tornado outbreak across the U.S. and has already left 16 people dead.

A rare Level 5 out of 5 severe weather threat looms over the South as a dangerous line of storms threatens strong, long-track tornadoes and damaging wind gusts through Saturday.

The violent storm has left 'multiple' people dead after tornadoes touched down in Missouri and an extreme fire risk warning was issued to South-Western states.

A dangerous Saturday into Saturday night is set to unfold across the Deep South and into parts of the Southeast as a prolific tornado outbreak hits at least half a dozen states. Threat level: The NOAA Storm Prediction Center has issued a rare "high risk" outlook indicating forecasters' confidence in numerous,

Forecasters expect the thunderstorms to swamp the South and move toward the East Coast on Saturday night into Sunday. Although the tornado threat is expected to decrease, the East Coast will likely face hail and potentially damaging wind gusts.