The latest report from the state weather bureau PAGASA shows that 30 areas in the Philippines are expected on Wednesday to have an 'init factor' level classified as "dangerous".

The Central Bicol State University of Agriculture in Pili, Camarines Sur, is forecasted to have the highest heat index, climaxing at 46°C.

Five areas are seen to have a heat index of 45°C: Dagupan City in Pangasinan, Aparri in Cagayan, San Jose in Occidental Mindoro, Puerto Princesa City, and Aborlan in Palawan.

Meanwhile, 44°C is expected in three areas: Ninoy Aquino International Airport (NAIA) in Pasay City, Metro Manila, Tuguegarao City in Cagayan, and Guiuan in Eastern Samar.

43°C is also predicted to be felt in nine areas: Science Garden in Quezon City, Central Luzon State University in Muñoz, Nueva Ecija, Sangley Point in Cavite, Coron in Palawan, Legazpi City in Albay, Virac (Synop) in Catanduanes, Masbate City in Masbate, Roxas City in Capiz, and Iloilo City in Iloilo.

Isabela State University in Echague, Isabela, Iba in Zambales, Baler (Radar) and Casiguran in Aurora, Ambulong in Tanauan, Batangas, Alabat in Quezon, Daet in Camarines Norte, Dumangas in Iloilo, La Granja in La Carlota, Negros Occidental, Catarman in Northern Samar, Catbalogan in Samar, and Tacloban City in Leyte, on the other hand, were seen to have their temperatures, at their highest at 42°C.

Baguio City and Benguet State University in La Trinidad still have the lowest estimated heat index, with 27°C and 28°C, respectively.

The heat index is the human discomfort index that gives the "apparent" temperature, or what humans perceive or feel as the temperature affecting their body, according to PAGASA.

The effect-based danger classification ranges from 42°C to 51°C, and its effects on the body are that heat cramps and exhaustion are likely, and heat stroke is probable with continued exposure.

The public is encouraged to take preventive measures against heat-related illnesses, whose symptoms include sweating heavily, exhaustion, dizziness, blacking out, vomiting, a feeling of nausea, and weakness despite a fast pulse, urging people to limit time spent outdoors, drink plenty of water, and wear protective and comfortable clothing outdoors.