SAN FRANCISCO (AP) — Rescuers were still searching for three people missing after a boat involved in a memorial service sank in the cold, fast-moving waters of San Francisco Bay near Alcatraz Island, authorities said Wednesday.

One person was pulled from the water but later died, and 16 others were rescued Tuesday afternoon after the boat took on water and capsized in what witnesses described as “rough seas,” San Francisco Fire Chief Dean Crispen said. A dog on board also died.

Search teams were using thermal imaging, tide prediction and modeling to guide their efforts, the department said Wednesday. By Tuesday evening, authorities had been searching the open ocean west of the Golden Gate Bridge.

Sudden immersion in water under 60 degrees Fahrenheit (15 degrees Celsius) can lead to cold water shock, a condition where people lose dexterity in minutes, which can be dangerous or deadly when trying to escape a sinking watercraft.

Some of the swells on the bay were up to 5 feet (1.5 meters), said Lt. Joseph England of the Richmond Police Department, who responded to the scene.

"The wind was coming underneath the Golden Gate and blowing toward Alcatraz,” England said Wednesday. “If you have a smaller vessel and you don’t know what you’re doing and you’re hitting those swells sideways, it can lead to disaster.”

The vessel was a 50-foot (15-meter) pleasure craft with a cabin and upper deck named Volare, registered out of Stockton, California, said Lt. Mariano Elias, a San Francisco Fire Department spokesperson.

There was no small watercraft advisory at the time, which would warn boaters about weather hazards. Conditions on the bay weren't unusual, with winds around 17 mph (27 kph), said Roger Gass, a meteorologist at the National Weather Service.

“There weren’t any factors at play as far as the weather goes,” Gass said Wednesday.

The U.S. Coast Guard is leading a search and rescue effort with an 87-foot (26-meter) cutter named the Barracuda, other vessels and a fixed-wing aircraft, said Petty Officer Kenneth Wiese.

Wiese said the Coast Guard has been searching nonstop since Tuesday and hadn’t yet determined how long crews will keep looking before switching to a recovery effort.

“We want to consider every single option,” he said.

England said no one was aboard by the time his department’s marine unit reached the vessel. The crew found the boat nearly submerged, with cushions, chairs and other debris floating nearby.

Initial callers reported what appeared to be smoke coming from the boat, but San Francisco police officers who first reached the vessel determined it was steam.

The boat departed at or near the St. Francis Yacht Club, passed under the Golden Gate Bridge twice and visited Angel Island State Park in the bay before the apparent return trip, according to the ship-tracking website VesselFinder. A person who answered the phone at the yacht club on Tuesday said he had no information. Angel Island is the largest natural island in the bay, with sweeping views of the city.

The maximum-security federal prison at Alcatraz Island, which closed more than 60 years ago, was infamously inescapable due to the chilly waters and strong currents that surround "The Rock.” Designed to hold the nation’s intractable criminals, including Al Capone and George “Machine Gun” Kelly, it is now a popular tourist attraction. The island is about a mile (1.6 kilometers) off San Francisco.

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Associated Press writers Kathy McCormack in Concord, New Hampshire; Ed White in Detroit; and photographer Noah Berger in San Francisco contributed to this story.