By Marjaleen Ramos

Tropical storm “Onyok” has intensified into a severe tropical storm as it moved over the Philippine Sea, the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) reported early Sunday.

Tropical Cyclone Wind Signal No. 1 remains hoisted over Batanes and Babuyan Islands.

Weather specialist Raymond Ordinario said Onyok may skirt the islands of Batanes and Babuyan on its way to southern Japan.

At around 4 p.m. Sunday, Onyok was spotted at 455 kilometers (km) east of Calayan, Cagayan.

Onyok is not expected to make landfall but may intensify into a typhoon within 24 hours. A tropical cyclone is classified as a typhoon if it has maximum wind speed of 118 to 220 kph.

From Sunday until Monday, the trough or extension of Onyok may bring scattered light to moderate rain showers and thunderstorms over Batanes, Cagayan, Isabela, Nueva Vizcaya, Quirino, Albay, Camarines Norte, Camarines Sur, Sorsogon, Catanduanes, and Masbate.

Meanwhile, Metro Manila and the rest of the country will have partly cloudy to cloudy skies with isolated rain showers due to localized thunderstorms.

The weather agency also warned fisher folks that sea travel will be risky over the northern and eastern seaboards of Northern Luzon, including those areas under TCWS No. 1 due to potentially rough sea conditions.

Should Onyok maintain its current speed and direction at 15 kph northwest, the cyclone will be outside the country’s area of responsibility by Monday. (With reports from Ellalyn de Vera Ruiz)