Extreme weather and powerful winds predicted for 100 million Americans

Sprawling storm system to affect vast swath of territory from Canada to Texas with tornadoes threatening in south

The National Weather Service has predicted extreme weather across a vast swath of the US encompassing more than 100 million people, with powerful winds gusts up to 80mph (130km/h) being forecast from the border with Canada to Texas.

A sprawling storm system crossing the US on Friday overturned semitrucks on highways and fanned wildfires in Texas and Oklahoma, where officials called for evacuations in at least one town. Tornado threats loomed for the Mississippi valley into the night and the deep south on Saturday.