San Francisco residents were woken up by a tornado warning early Saturday morning during a powerful storm system that battered the region with heavy rain and wind.

A powerful storm swept through parts of Northern California early Saturday, knocking down trees, causing widespread power outages and prompting weather officials to issue what they said was the first-ever tornado warning for San Francisco.

For the first time in recorded history, downtown San Francisco was included in a tornado warning on Saturday as severe storms swept through the city, just one week after a tsunami warning triggered widespread panic in the region.