Texas Tornadoes from above by Drone
An aerial image taken Sunday by drone, December 27, 2015 shows the path of a tornado in Rowlett, Texas. Violent storms ripped through the North Texas area late Saturday, spawning tornadoes that killed 12 people.
At least eight people died in Garland, near Dallas, five of them when their cars were blown off a motorway.
In west Texas, snow combined with high winds to cause drifts that left a number of roads impassable.
Heavy rains have caused flooding further north, leaving 12 people dead in Missouri and Illinois.