Tropical storm "Maring" (international name "Kompasu") has merged with the remnants of tropical depression "Nando" and started moving north-northwestward over the Philippine Sea before Sunday noon, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said in its 11 a.m. bulletin.
Tropical cyclone wind signal number 1 is currently in effect in 17 areas due to the anticipated direct effect of the merger cyclone.
PAGASA raised Signal No. 1 over Batanes, Cagayan including Babuyan Islands, Isabela, Apayao, Abra, Kalinga, Mountain Province, Ifugao, northern portion of Benguet, Ilocos Norte, Ilocos Sur, Catanduanes, Eastern Samar, eastern portion of Northern Samar, eastern portion of Samar, Dinagat Islands, and Surigao del Norte.
Possible landfall over mainland Luzon 'not ruled out'
As of 10 a.m., the center of tropical storm Maring was estimated at 730 kilometers east of Tuguegarao City.
PAGASA said Maring will likely move west-northwestward toward the extreme northern Luzon in the next few hours.
Afterward, the storm may move generally westward over the Luzon Strait and pass close or over the Babuyan Islands between Monday evening, Oct. 11, and Tuesday, Oct. 12.
However, PAGASA maintained that the possibility of landfall over mainland Luzon is not ruled out at this time.
The merger cyclone is seen to gradually intensify and may be upgraded into a severe tropical storm category within the next 24 hours.
Maring remained a tropical storm with maximum sustained winds of 85 kilometers per hour (kph) near the center and gustiness of up to 105 kph before Sunday noon.
Heavy rains, strong winds prevail
PAGASA said Maring is enhancing the southwesterlies, which may bring rains over Western Visayas, Zamboanga Peninsula, Palawan, and Occidental Mindoro in the next few hours.
Maring may also bring moderate to heavy rains over Catanduanes, while light to moderate with at times heavy rains may prevail over the rest of Bicol Region and the Visayas.
PAGASA advised affected residents to remain vigilant against possible isolated scattered flooding, including flash floods, and rain-induced landslides especially those in areas that are highly susceptible to these hazards.
Moreover, strong winds with higher gusts will prevail in areas where Signal No. 1 is currently in effect.
However, due to the expansive wind field of the tropical storm and the gradual enhancement of the southwesterlies and northeasterlies, PAGASA said that occasional gusts reaching strong breeze to near-gale in strength will likely be experienced over the coastal and upland or mountainous areas of Mimaropa (Oriental Mindoro, Occidental Mindoro, Marinduque, Romblon, Palawan), Bicol Region, Visayas, Caraga, and Northern Mindanao even in the absence of wind signals.