Heavy rains brought by an approaching storm triggered flooding and multiple landslides in the southern Philippines, killing at least 31 people, a senior government official said on Friday, as rescuers searched for missing residents.

Authorities have evacuated thousands of people out of the path of tropical storm Nalgae, which could possibly make landfall Friday night in Samar province in central Philippines, disaster officials said.

Naguib Sinarimbo, interior minister of the Bangsamoro Autonomous Region in Mindanao (BARMM), said the rainfall in Maguindanao province had exceeded expectations.

"There were preparations made but unfortunately, the rainfall was more than what people had expected," Sinarimbo said.

In the southern province of Sultan Kudarat, rescue workers used rubber boats to get to residents trapped in chest-deep waters, images shared by the coast guard showed.

Landslides and floods are frequent in the Philippines, due in part to the growing intensity of tropical cyclones that regularly batter the country. The Philippines sees an average 20 typhoons a year.

Tropical storm Nalgae, packing winds of 75 km (47 miles) per hour, forced flight cancellations just as thousands of people were planning to travel to their home towns to observe All Souls Day. Schools were also shut down and some ports saw operations paralysed.

The storm could intensify further while moving over the Philippine Sea, the weather bureau said.