Light to moderate rain are forecast over Aurora, Quezon, the Camarines provinces, Mindoro, Marinduque and Romblon on Thursday, the weather bureau said.
The low pressure area (LPA) being monitored by the Philippine Atmospheric, Geophysical and Astronomical Services Administration was last observed 115 kilometers east of Casiguran, Aurora.
Pagasa earlier said it was not likely to become a cyclone.
Nonetheless, it added that partly cloudy to cloudy skies with isolated thunderstorms will prevail over Metro Manila and the rest of the country.
Moderate to occasionally strong winds blowing from the southeast to the south will prevail over Northern Luzon and its coastal waters will be moderate to occasionally rough.
Elsewhere, winds will be light to moderate coming from the south moving southwest resulting in slight to moderate seas.