SAN FRANCISCO -- Howard Kuljian and his family were out for a walk on a damp, overcast morning at Big Lagoon beach, playing fetch with their dog as 10-foot surf churned the water just feet away like a washing machine.
Signs near the beach warned of "sneaker waves," the kind that suddenly roar ashore.
Kuljian tossed a stick that took their dog down to the water's edge, and in an instant, authorities said, a wave swallowed it, setting off a nightmarish scramble early Saturday in Arcata.
"Everything kind of snowballed from there," Coast Guard Lt. Bernie Garrigan said.
Kuljian's son ran to save the dog and struggled as he was captured by the surging surf. Kuljian followed, and later his wife. On shore, his 18-year-old daughter and his son's girlfriend could only watch.
Both parents' bodies were later recovered, but the boy -- presumed dead -- is still missing.
The dog, identified by the boy's friend as "Fran," eventually made it back to shore.
Students at the high school that Kuljian's son, Gregory, attended wore green in his memory.
By late Monday afternoon, more than 1,300 people "liked" a Facebook page set up by the teenager's friends called "Wear Green for Geddie" -- using his nickname. Dozens tweeted tributes with the hash-tag #WearGreenGorGeddie.
"I will always remember him no matter how long," wrote Emmalaya Owen on the Facebook page. "Especially how he was such an upbeat happy person or how he tried to put up 'Be Happy' propaganda posters he drew around school."
Others were trying to come to terms with the deaths. His sister, Olivia, graduated from the school last year.
"He was just a friendly guy, and everyone who knew him liked him, and his family was very close," said Day Robins, a high school senior. She said Gregory and his family were active in school athletics and sailing.
Big Lagoon beach is a short drive from Arcata. Signs are posted near the parking lot warning beachgoers not to turn their back to the surf and to pay special attention to "sneaker waves," Garrigan said.
"Because the beach is designed that way, when that 10-foot wall breaks, it surges up on the beach and surges back really fast," he said. "It's like a cyclical washing machine."
As the family walked along the beach, Howard Kuljian threw the stick, and the dog gave chase, said Dana Jones, a state parks district superintendent.
Seeing his son in the water, Howard Kuljian, 54, leapt to action and disappeared into the frigid water.
Gregory managed to pull himself back onto the sand, but after realizing his father was drowning, both he and his mother, 57-year-old Mary Scott, went in to the cold sea to save him.
As Olivia and the girlfriend watched in horror, a nearby bystander called police.
By the time help arrived, it was too late. Jones said the officer wasn't able to get to the family members because of the high surf.
Garrigan said the search for the teenager was stopped because a person without a wetsuit could not survive for long in the surf because of the temperature of the water.
The Coast Guard deployed a helicopter and two motor life boats to search for the teenager, but thick coastal fog made the search difficult. The parks department has also called off its search.
"When there is shorebreak like that, you don't even have to go into the water to be pulled into the sea," Jones said. "It's a reminder to be real careful around the ocean."