(CNN) -- Torrential rainfall unleashed flooding and spawned a rare tornado warning in California on Tuesday as a series of storms moved through, with more expected Wednesday and Thursday.
Weather-related problems also affected Northern California, where Fresno's Yosemite International Airport lost the ability to send passengers through security because of a power outage.
Landings and takeoffs were not affected, because a backup system kicked in, said Vikkie Calderon, airport spokeswoman. However, the backup system for the lobby did not kick in.
Airlines were remotely checking passengers in Tuesday afternoon, but the outage prevented security screenings until power was restored, Calderon said. By midafternoon, security screenings had resumed.
In Southern California, a possible tornado was reported in Huntington Beach by the Orange County emergency manager, the National Weather Service reported. Boats in the nearby harbor and some buildings in the area were damaged, and a vehicle was flipped.
As of Tuesday afternoon, about 50 people were in the process of being evacuated from homes in the San Pedro area of Los Angeles because of severe flooding, according to Los Angeles Police Department Officer Gregory Baek. About 20 vehicle rescues took place in the same area, he said.
Video from CNN affiliate KCAL showed flooding in Long Beach, where a boater was using a raft to navigate flooded streets lined by cars with water up over their headlights.
A rare tornado warning was issued Tuesday afternoon for southeastern Orange County, including the cities of Mission Viejo and San Clemente, and northwestern San Diego County, including the cities of Oceanside and Carlsbad. The National Weather Service said radar indicated a severe thunderstorm capable of producing a tornado.
A 93 mph wind gust was reported by lifeguards at the Newport Beach pier, the weather service said. Gusts of 72 mph and 73 mph were also measured.
Piers in Orange County were closed because of high surf, according to the Orange County Fire Authority. There were some reports of damage and flooding, but no known injuries, officials said.
Forecasters warned the rainfall could trigger slides in recent burn areas and also warned about damaging winds. Some areas received as much as 3 inches of rain on Monday and could see an additional 2 inches Tuesday, the weather service said. Even stronger storms, with heavy rain and powerful winds, are forecast to hit the region Wednesday and Thursday.
Wind and rain prompted power outages Monday in Southern California, according to Southern California Edison.
CNN's Sara Pratley, Chad Myers, Rosalina Nieves and Lynn Lamanivong contributed to this report.