A yellow rainfall warning was raised over areas in Nueva Ecija, Bulacan, and Quezon on Saturday afternoon due to the effect of a shear line, according to the state weather bureau. Based on the 2 p.m. advisory of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa), a yellow warning level (be alert), which indicates a rainfall between 7.5 millimeters (mm) and 15 mm, is expected over the following areas in the three provinces:
Nueva Ecija (Bongabon, Gabaldon, Laur, Pantabangan, Rizal, General Mamerto Natividad, Palayan, Llanera, San Jose, Talavera, Science City of Munoz, Cabanatuan, Santa Rosa, General Tinio, Penaranda, Santo Domingo, Gapan, San Leonardo, Jaen, Aliaga, Quezon)
Bulacan (Dona Remedios Trinidad, San Miguel)
Quezon (General Nakar).
Under the yellow rainfall warning level, flooding in flood-prone areas is possible.
Meanwhile, the shear line is also expected to bring light to moderate with occasional heavy rains over Metro Manila and other provinces within the next three hours:
Metro Manila (Caloocan, Valenzuela, Navotas, Malabon)
Pampanga
Tarlac
Bataan
Zambales
Nueva Ecija (Carranglan, Lupao, Talugtug, Cuyapo, Guimba, Nampicuan, Licab, Zaragoza, San Antonio, Cabiao, San Isidro)
Bulacan (San Ildefonso, San Rafael, Angat, Norzagaray, Baliuag, Bustos, Santa Maria, Pandi, Pulilan, Plaridel, Calumpit, Hagonoy, Paombong, Malolos, Bulakan, Guiguinto, Bocaue, Balagtas, San Jose del Monte, Meycauayan, Marilao, Obando)
Quezon (Panukulan, Burdeos, Polillo, Patnanungan, Jomalig)
Rizal (Rodriguez)
A shear line, as Pagasa defines, occurs when the northeast monsoon (amihan) converges with easterlies or the warm winds coming from the Pacific Ocean.