A massive rogue wave overrode coastal barriers and sent onlookers scattering in the California beach town of Ventura.
Eight people were sent to the hospital in the incident, according to the Ventura County Fire Department.
“For your safety, please avoid the area near the ocean, as it can be quite dangerous,” the department wrote on Facebook alongside a video of the freak occurrence.
Powerful storms in the Pacific have sent waves as large as 40 feet tall into the California coast this week.
“It was a combination of many factors that brought about that surge in Ventura and Ventura Harbor,” Ariel Cohen of the National Weather Service told SFGate. “At the time of high tide, we had a tremendous amount of wave energy … and the collection of all that energy resulted in a surge of water that extended into coastal Ventura. It was midday when this happened; the flooding was occurring at other points during the day as well.”
Elsewhere, sneaker waves jumped sea walls and soaked onlookers in Santa Cruz and at the famed big-wave surfing locale Mavericks in Northern California.
National Weather Service flood and high surf warnings are in effect through Saturday in Northern California and Monday morning in Southern California.
“Dangerously large breaking waves of 28 to 33 feet with isolated waves up to 40 feet,” may occur, the NWS said of conditions in Northern California.
“Large breaking waves may sweep people off jetties and docks,” it added of conditions in Southern California. “Strong rip currents will pose a risk of ocean drowning. Beach erosion is likely.”
Flooding has already occurred in the cities of Aptos, Ventura, and Oxnard.
Residents of Ventura were seen paddleboarding through flooded streets.
"The waves were big," Ventura resident Brian Scott told ABC7. "I mean, I’m a water guy. I sail, scuba dive. These were 15+ foot waves this morning at high tide. Never seen that. We’ve been here for 10 years."
The risky conditions were also seen in Hawai’i, where Honolulu Ocean Safety lifeguards on Oahu rescued 20 people as of Wednesday.
