ARLINGTON, Va. − A wall of snow, ice and rain was sweeping across the Northeast on Thursday, the first in a series of storms forecast to wallop much of the nation's northern tier over the next several days.

Thunderstorms caused flash flooding in portions of West Virginia and spawned a tornado in Kentucky, while a wintry mix coated trees and roads and even dropped “thunder ice” in several

Residents and storm spotters in portions of Indiana, southern Michigan, Ohio and Pennsylvania reported the unusual mix of freezing rain accompanied by flashes of lightning in the unstable air.