MANILA— Weather disturbance Siony intensified into a severe tropical storm Wednesday afternoon, the state weather bureau said, prompting a warning signal in parts of Northern Luzon.

PAGASA said Siony intensified into a severe tropical storm at 2 p.m. and is expected to intensify further into a typhoon prior to its landfall or close approach over extreme northern Luzon.

The country's 19th storm, which comes as provinces in Bicol reel from devastation due to Super Typhoon Rolly, was last estimated 735 kilometers east of Basco, Batanes as of 4 p.m., packing maximum winds of 95 kms per hour near the center and gustiness of up to 115 kph, PAGASA said.

Tropical cyclone warning signal no. 1 was hoisted over the following areas, where 30 to 60 kph winds may rip roofs off nipa and cogon huts, damage rice crops and down banana plants:

• Northeastern portion of mainland Cagayan (Santa Ana, Gonzaga)
• Eastern portion of Babuyan Islands (Balintang Islands, Babuyan Islands, Didicas Islands, and Camiguin Islands including their adjoining islets)

Siony is moving east "slowly" and is forecast to keep its pace or "remain almost stationary" in the next 6 to 12 hours, after which it will head westward or west-northwestward towards the Luzon Strait and extreme Northern Luzon, according to PAGASA.

The northeasterlies and Siony's trough will bring light to moderate with at times heavy rains over Bicol Region, Aurora, Quezon, and the eastern portions of Cagayan and Isabela, the weather bureau said.

It warned that flooding and rain-induced landslides may occur during heavy or prolonged rainfall especially in areas that are highly susceptible to these hazards and/or those that received significant antecedent rainfall from previous storms.

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