Yellow heavy rainfall warning is currently up over Zambales and Bataan.
This alert was announced by PAGASA before noon on Thursday.
The weather bureau says, this means that at this time, flooding may be happening in some portions the two provinces.
PAGASA adds, Cavite and Batangas may also experience thunderstorms which may result in flashfloods.
Metro Manila and nearby provinces will have light to moderate rains.
The rains are brought by the southwest monsoon which is enhanced by typhoon Noru outside the Phiilippine Area of Responsibility (PAR).
Noru is heading towards Japan.
On Thursday, it was spotted 1,565 kilometers east northeast of extreme Northern Luzon.
Heavy rains and floods prompted the suspension of school classes in some areas in Rizal, Antipolo City and Cavite.