A major storm in the US killed two people after hitting northern California and the Pacific Northwest.
It moved south overnight, prompting evacuation orders in areas prone to floods and mud flows.
The National Weather Service forecast the system to track through southwestern California, bringing the possibility of strong thunderstorms, as well as waterspouts and small tornadoes along the coast.
As the storm loomed, officials in the Los Angeles suburb of Lendora issued a mandatory evacuation order in the area hit by a fire that burned some 2,000 acres in January.
The Riverside County Sheriff's Department also ordered some residents in San Jacinto, which sparked mud flows during a large storm last week, to evacuate.
The latest storm drenched northern California, flooding some streets and intersections in the San Francisco area.
Many local schools were closed.
The city saw about 8.6cm of rain today nearly surpassing a one-day record and 240 departing and incoming commercial flights were cancelled at San Francisco International Airport while others were delayed for more than two hours officials said.
The harsh weather also hit Washington state, where over 165,000 customers were without power as of early today, according to local utility companies
In southern Oregon, a homeless man camping with his 18-year-old son was killed yesterday morning when a tree toppled on to their tent, the Jackson County Sheriff's Office said.
Elsewhere, Portland police said a tree fell on a car that then swerved into another tree, killing the teenage passenger and seriously injuring the adult driver.
Portland General Electric Co and Pacific Power reported nearly 41,000 customers remained without power, as a storm system with wind gusts of 130km/h moved through Oregon.
"In certain parts of the west coast this could be the most significant storm in 10 years," National Weather Service meteorologist Eric Boldt said.
Police in the central California city of Santa Cruz, said a tree fell on an 11-year-old student, pinning his arm and shoulder until emergency workers could cut him free with chainsaws.
The child's injuries were not believed to be life threatening.
The storm was expected to provide little relief from California’s record, multi-year drought that has forced water managers to sharply reduce irrigation supplies to farmers and prompted drastic conservation measures state wide, weather officials said.
