Violent weather has caused widespread disruption along much of the US west coast. The storms extended from Washington state to Southern California before moving inland and dumping heavy snow across the mountain states.

The weather system was powerful enough to spawn a tornado in Northern California near the town of Denair, near Modesto, on Sunday.

There were no reports of casualties, but it did damage buildings, down trees and cause power outages.

Nearly 18,000 customers were without power in Los Angeles, as the winds gusted in excess of 100km per hour.

On Monday, Department of Water and Power crews were still trying to restore power to more than a dozen neighbourhoods, including parts of Hollywood.

San Francisco was also badly hit. Authorities say nine people and a dog were rescued in two incidents as strong winds caused high surf conditions in the Bay Area.

The system is now in the process of moving inland and is increasingly turning to snow as it moves over the higher ground. The National Weather service expects up to 45cm of snow to fall over the Eastern Plains of Colorado.

Utah has already had a good covering of snow. In Parley's Canyon, several cars slid off the roads as they drove through the white-out conditions.

Snow was, however, welcomed at the ski resort town of Park City with 15cm falling by midday on Monday.

The snow is expected to melt at lower levels, but will stick around the higher ground. Elsewhere, warnings have also been issued for significant accumulations of snow and dangerous driving conditions in northern Arizona and New Mexico.

Source: Al Jazeera and agencies