Siony decelerates over Philippine Sea; forecast track still uncertain

Tropical Storm Siony has further decelerated over the Philippine Sea and is set to become quasi-stationary in the next 36 hours, PAGASA said late Monday night.

In its 11 p.m. bulletin, the state weather bureau said the center of Siony was last seen 605 kilometers east of Basco, Batanes, with maximum sustained winds of 65 kilometers per hour and gustiness of up to 80 kph.

The cyclone is slowly moving northward.

“A landfall scenario over Batanes-Babuyan Islands area around Friday remains likely,” PAGASA said.

“However, due to the projected quasi-stationary state of this tropical storm in the next 36 hours, there remains a high degree of uncertainty in the forecast track,” it added.

PAGASA also said Siony will likely intensify into a Severe Tropical Storm on Wednesday and become a typhoon on Thursday prior to its approach or landfall over extreme Northern Luzon.

Forecast positions

By Tuesday evening, Siony will be 705 kilometers east of Basco, Batanes then on Wednesday evening, will move to 665 kilometers east of Calayan, Cagayan.

On Thursday evening, the cyclone will be 225 kilometers east of Calayan, Cagayan.

By Friday evening, it will be outside the Philippine Area of Responsibility or 360 kilometers west of Basco, Batanes.

Hazards

The northeasterlies and the trough of Siony are expected to bring light to moderate with at times heavy rains over Batanes, Apayao, Cagayan, and Isabela from Monday night until Tuesday morning.

PAGASA warned that flooding and rain-induced landslides may occur during heavy or prolonged downpour.

The northeasterlies enhanced by Tropical Storms Siony and Rolly will also cause strong to near gale conditions with higher gusts over Batanes, Babuyan Islands, and the northern portions of Cagayan and Ilocos Norte.

Meanwhile, Siony and Rolly will bring rough to very rough seas over the entire seaboards of Northern Luzon and the western seaboard of Central Luzon as well as moderate to rough seas over the remaining seaboards of Luzon and the eastern seaboards of Visayas and Mindanao. -- BAP, GMA News