The system will put over 100 million people at risk of severe weather, from blizzard conditions in the northern Plains to tornadoes in the South.

A potent March storm continued its cross-country trek Thursday, a system that could bring "the most significant severe weather outbreak of the year" to portions of the central and eastern U.S. on Friday and Saturday,

Scientists said the storm's strength and potential for far-reaching impacts is notable, but its timing isn't unusual.