The Philippines on Sunday braced for the arrival of Typhoon Utor, warning of heavy rains and potential floods in what is expected to be the strongest storm to hit the country so far this year.

The typhoon, packing gusts of up to 185 kilometres (115 miles) per hour, was 160 kilometres northeast of the nation's easternmost island Catanduanes as of 0200 GMT, the state weather bureau said.

"This is forecast to be the strongest storm to make landfall so far this year," bureau head Vicente Malano told reporters.

The typhoon is expected to make landfall in the north-eastern agricultural province of Aurora early morning on Monday, he said, adding that heavy rains are likely to cover a larger area including the capital Manila.

Utor, moving west-northwest at 19 kilometres per hour, was forecast to dump up to 25 millimetres of rain an hour within a 600-kilometre diameter of the typhoon, the bureau said.

"Residents in low lying and mountainous areas... are alerted against possible flash floods and landslides," it stated in an advisory.

The bureau also warned seafarers to remain at port due to strong waves, as the police, military and emergency relief authorities were placed on high alert.

The Philippines is hit by about 20 storms and typhoons each year, some of them devastating.

Nearly 2,000 were killed or went missing in flash floods and landslides when Typhoon Bopha cut across the southern island of Mindanao in December last year.

About 850,000 people were also displaced, and many of them remain in temporary shelters months after the typhoon.

The Hong Kong Observatory had classified Utor as a "severe typhoon" on its website Sunday.