MANILA - The low pressure area east of Surigao del Norte strengthened into tropical depression Jolina on Monday morning, the state weather bureau said.

The storm was last estimated based on all available data at 300 kilometers east southeast of Guiuan town, Eastern Samar at 4 a.m., moving west southwest at 20 km per hour while packing maximum winds of 45 kph near the center and gusts of up to 55 kph, PAGASA said in its 5 a.m. bulletin.

Tropical cyclone warning signal no.1, which will bring strong winds within 36 hours, was raised in the following areas:

- Eastern Samar
- Dinagat Islands
- Siargao Islands
- Bucas Grande Islands

On Monday, "Jolina" is expected to bring moderate to heavy rains over Eastern Samar, Dinagat Islands, and Surigao del Norte including Siargao and Bucas Grande Islands.

Under these conditions, isolated to scattered flash flooding and rain-induced landslides are possible especially in areas that are highly susceptible to these hazards, PAGASA warned.

The storm may also bring moderate to rough seas (1.2 to 2.8 m) over the eastern seaboards of Visayas and Mindanao, it added.

"Jolina" is forecast to move westward or west-southwestward in the very short term before turning generally northwestward.

It is expected to remain a tropical depression until its potential landfall over Northern Luzon by Friday, when it is forecast to weaken into an area of low pressure, according to PAGASA.

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