The National Weather Service issued an ice storm warning​ for parts of the area and winter weather advisories for other areas in western Pennsylvania.

The storm left trees and roads in several mid-Atlantic states coated in ice before warmer temperatures moved in.

Storms spawned at least one tornado, sent creeks over their banks and caused flash flooding Thursday in portions of West Virginia and Kentucky, while a wintry mix coated trees and roads in ice and even dropped "thunder ice" in several states.

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.

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.

Starting with an ice and snow storm Thursday, a series of winter systems is forecast to slam parts of the Midwest, Northeast and Mid-Atlantic with dangerous travel conditions through the middle of next week,