File photo. Photograph:( AFP )
Heavy rains are forecast to swell rivers, cut off roads and threaten low-lying communities in Cagayan province, where officials guided residents towards shelter
Kalmaegi is expected to batter the nation's lightly populated far north with 120 kilometres (75 miles) per hour winds, the national weather service said.
Heavy rains are forecast to swell rivers, cut off roads and threaten low-lying communities in Cagayan province, where officials guided residents towards shelter.
"We're expecting falling trees and houses that could be inundated by floods," provincial police chief Ariel Quilang told AFP.
Forecasters believe a second tropical storm could make landfall in the same province by Thursday.
The disaster-prone nation is hit by an average of 20 storms and typhoons each year, killing hundreds and condemning many areas in their path to perpetual poverty.
The weather bureau raised landslide warnings across the mountainous interior of the country's north, also warning of floods and waves up to two metres (6.5 feet) high in coastal areas.
At least a dozen domestic flights have been cancelled and schools shut down due to Kalmaegi, while small sea vessels were ordered to stay ashore with gale conditions forecast at sea.
The Philippines' deadliest cyclone on record was Super Typhoon Haiyan, which left more than 7,300 people dead or missing in 2013.