Tornadoes have swept through the Dallas area leaving substantial damage and at least seven people dead either from the storm or related traffic accidents, in the latest of a succession of freakish winter weather events across the country that on Sunday also could include heavy snow and massive flooding.

The Texas tornadoes that touched down after dark on Saturday followed days of tumultuous weather in the Southeast including unusual winter tornadoes that left 18 people dead there over the Christmas holiday period.

National Weather Service Meteorologist Anthony Bain in Fort Worth said several tornadoes touched down in the Dallas area, although the full extent of damage would not be known until daylight Sunday.