The police, coast guards and a Marines diving team were searching on Sunday for a family of seven at Taal Lake in Batangas.
“The waters from the mountains hit their home in Balete town, causing it to be swept away with them possibly inside,” Malinao, the provincial police chief, said.
Most of the deaths in Batangas have been attributed to rain-induced landslides.
More than 20 bodies were pulled from heaps of mud, boulders and fallen trees, while police said at least another 20 people in the province are still missing.
“We will continue searching until all bodies are retrieved,” Malinao said.
The national disaster agency said Sunday that about 560,000 people had been displaced by floods, which submerged hundreds of villages in swaths of the northern Philippines.
About 20 big storms and typhoons hit the archipelago nation or its surrounding waters each year, damaging homes and infrastructure and killing dozens of people.
A recent study showed that storms in the Asia-Pacific region are increasingly forming closer to coastlines, intensifying more rapidly and lasting longer over land due to climate change.