MANILA, April 15 -- The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) warned of dangerous heat index levels in nine areas on Monday.

Based on the weather bureau's 5 p.m. forecast on Sunday, the following areas may have a heat index ranging from 42 degree C to 45 degree C on Monday:

NAIA Pasay City, Metro Manila - 42 degree C Laoag, Ilocos Norte - 42 degree C Dagupan City, Pangasinan - 45 degree C Aparri, Cagayan - 43 degree C Tuguegarao, Cagayan - 42 degree C ISU, Echague, Isabela - 42 degree C Clark Airport, Pampanga - 42 degree C Puerto Princesa City, Palawan - 44 degree C Aborlan, Palawan - 42 degree C Virac, Catanduanes - 42 degree C Masbate City, Masbate - 42 degree C Zamboanga City, Zamboang...