MANILA - (UPDATE) Tropical storm Onyok has intensified into a severe tropical storm as it traversed the Philippine Sea towards extreme northern Luzon, the state weather bureau said early Sunday.

Tropical cyclone wind signal no. 1 was still hoisted over Batanes and Babuyan Islands.

As of 10 a.m., Onyok was last spotted 500 kilometers east of Tuguegarao City, Cagayan, moving northwest at 15 kilometers per hour (kph) and packing maximum winds of 100 kph and gusts of up to 125 kph.

It will bring scattered light to moderate rains over Cagayan Valley and Bicol region, PAGASA said.

Onyok, although unlikely to make landfall, might intensify into a typhoon within 24 hours.

PAGASA said sea travel is risky, especially for small seacraft, over seaboards under the wind signal due to potentially rough sea conditions.

Visit the ABS-CBN Weather Center for updates.