HONG KONG (AP) -- Tropical Storm Matmo edged closer to the Philippines on Thursday and was expected to intensify into a typhoon that could threaten southern China this weekend, just about a week after the region was battered by Ragasa, one of the strongest storms to hit Asia in years.

Matmo, which had maximum sustained winds of 65 kph (40 mph), is forecast to move west-northwest to the vicinity of Luzon, the Philippines' most populous region, at about 22 kph (13 mph), according to Hong Kong's observatory on Thursday morning. The country's central region was already grappling with the aftermath of an earthquake that killed dozens of people.

The Philippine weather agency said it may make landfall over southern Isabela province or northern Aurora province on Friday, and is expected to cross northern Luzon. It warned of a moderate risk of life-threatening storm surge in the next 36 hours in some low-lying areas, saying sea travel is risky for all types of vessels.

The Hong Kong observatory forecast Matmo will enter the South China Sea after hitting the Philippines and intensify into a typhoon, bringing winds and showers to the Asian financial hub over the weekend.

It is expected to hit coastal area of neighboring Guangdong province, the southern Chinese economic powerhouse, on Sunday before moving northwest into the Guangxi region and eventually dissipate around Yunnan province in southwestern China next week.

Some residents in southern China anticipated deteriorating weather as they mark the midautumn festival Monday, a time of family gatherings and lantern carnivals.

South China, including Hong Kong, has had an unusually high number of typhoons this year, far exceeding the seasonal norm, the City University of Hong Kong said last week. Its statement was issued as Super Typhoon Ragasa - the world's strongest cyclone of the year, which once packed maximum sustained winds reaching 265 kph (165 mph) -- approached the city before weakening and entering northeastern Vietnam.

Earlier this week, Typhoon Bualoi left a deadly trail of destruction in Vietnam.

Its prime minister ordered urgent relief efforts after flooding and landslides triggered by Bualoi struck 17 northern and north-central provinces. More than 158,000 houses were destroyed, damaged or submerged, thousands of roads were blocked and at least 27 people died in Vietnam.

Flooding in the capital, Hanoi, isolated many neighborhoods for more than a day. Though rains eased by Wednesday, large swaths of hard-hit Nghe An province remained deeply flooded.

___

Associated Press writer Aniruddha Ghosal contributed to this report from Hanoi, Vietnam.

Tropical storm edges toward the Philippines and may grow to a typhoon on path toward China