By Curtis Skinner
SAN FRANCISCO (Reuters) - A major storm that pummeled northern California and the Pacific Northwest with heavy rain and high winds and killed two people 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 late on Thursday and into Friday, brining 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 Glendora issued a mandatory evacuation order in the area impacted by the Colby Fire that burned some 2,000 acres in January.
The Riverside County Sheriff's Department also ordered some residents in San Jacinto, which saw mud flows during a large storm last week that damaged homes and vehicles, to evacuate.
The system drenched northern California on Thursday, flooding some streets and intersections in the San Francisco area. Many local schools were closed.
The city saw about 3.4 inches of rain on Thursday, nearly surpassing a one-day record, and some 240 departing and incoming commercial flights were canceled 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 Friday, according to local utility companies.
In southern Oregon, a homeless man camping with his 18-year-old son was killed on Thursday morning when a tree toppled onto their tent, the Jackson County Sheriff's Office said.
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 of early Friday, as a storm system with wind gusts of 80 mph (129 kph) 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 on Thursday morning, 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 statewide, weather officials said.
(Additional reporting by Dan Whitcomb in Los Angeles; Editing by Angus MacSwan)