Stormy weather since late December has killed 56 people in the Philippines and left at least 19 missing, mostly fishermen lost in rough seas, disaster authorities said Tuesday.

Rescuers in Davao del Sur province, one of the areas hit hard by stormy weather in the Philippines, help children to an evacuation centre. (Froilan Gallardo/Associated Press)

Raging floodwaters and landslides from unseasonable rains that hit 25 provinces in the central and southern Philippines accounted for most of the deaths, according to the government's National Disaster Risk Reduction and Management Council.

The coast guard said four fishermen were missing from a boat that capsized and broke apart Sunday in stormy waters off Palawan province southwest of Manila. Thirty-three men were rescued.

Lt.-Cmdr. Armand Balilo, a coast guard spokesman, said the boat captain and his surviving crew members were able to paddle their lifeboats to an island.

An additional 13 fishermen have been missing since Sunday in the Bicol region southeast of the capital, the regional Office of Civil Defence said.

Two other men are missing in flooded villages in a southern province.

The disaster council said in a report early Tuesday that 53 people have been killed since late December.

Three others, including a one-year-old infant girl, drowned in a flash flood that hit their village outside Santa Cruz township in southern Davao del Sur province late Monday, said Minda Quejada, a midwife who supervised relief assistance for 810 families who fled their homes. These deaths have not yet been included in the council's casualty report.

The floodwaters in Santa Cruz were neck-deep in some areas and inundated a highway on Tuesday, stranding thousands of commuters in hundreds of vehicles that lined a five-kilometre stretch of the road waiting for the flood to recede.

About 1.6 million people have been affected by the rains and more than half a million were provided relief assistance, the disaster council said.

The unusually heavy rains at this time of the year have been caused by a cold front that has been aggravated by the La Nina weather phenomenon,which refers to cooler-than-normal surface temperatures over parts of the Pacific Ocean, said Graciano Yumul, chief of the national weather bureau.

"[The year] 2011 for the Philippines appears to be a wet year," he said, adding that typhoons expected this year will be more intense because of La Nina.