MANILA -- The weather bureau on Wednesday placed three Northern Luzon provinces under signal number 1 after Tropical Depression "Domeng" maintained its strength as it continues to move northwest of the country.

Placed under storm signal number 1 are the provinces of Cagayan, Aurora, and Isabela.

Domeng was spotted at 460 kilometers east northeast of Virac, Catanduanes at 2 a.m. Wednesday, with maximum winds of 45 kilometers per hour near the center.

Philippine Atmospheric, Geophysical, and Astronomical Services Administration (Pagasa) said Domeng is expected to be at 330 kilometers East of Aparri, Cagayan on Thursday morning.

On Friday morning, Domeng will be at 120 kilometers north of Aparri, Cagayan or 30 kilometers north northeast of Calayan. On Saturday morning, it will be at 360 kilometers West of Basco, Batanes.

Residents living in low lying and mountainous areas under signal number 1 were alerted against possible flashfloods and landslides.

Earlier, the weather bureau said that about 13 to 15 tropical storms are expected to enter the Philippine area of Responsibility this year, with three coming from this month alone. (Sunnex)