Dagupan City is facing a sizzling hot Saturday as weather bureau PAGASA forecasts the heat index in the city to reach 48 degrees Celsius.

This will be the 2nd straight day that Dagupan will experience 48-degree heat index, after 3 straight days of recording 47-degree weather, the weather bureau said.

Aparri, Cagayan is next on the “hottest” list, with a PAGASA forecast of 46 degrees Celsius.

Five areas are forecast to experience 45-degree Celsius heat index this Saturday: Sinait, Ilocos Sur, Bacnotan, La Union, Tuguegarao City, Cagayan, CBSUA-Pili, Camarines Sur, and Guiuan, Eastern Samar.

Another six areas will experience 44-degree Celsius heat index: Laoag City, Ilocos Norte, Cubi Pt. In Subic Bay, Olongapo City,  Sangley Point in Cavite, Aborlan in Palawan, Virac (Synop) in Catanduanes, and Roxas City in Capiz.

Metro Manila is facing another hot day with heat index reaching 43 degrees Celsius, according to the weather bureau.

Other areas facing 43 degrees Celsius heat index are:

MMSU, Batac, Ilocos Norte

ISU Echague, Isabela

Iba, Zambales

Clark Airport (DMIA), Pampanga

Baler (Radar), Aurora

Casiguran, Aurora

Coron, Palawan

San Jose, Occidental Mindoro

Legazpi City, Albay

Iloilo City, Iloilo

Dumangas, Iloilo

La Granja, La Carlota, Negros Occidental

Catarman, Northern Samar

Catbalogan, Samar

Tacloban City, Leyte

Zamboanga City, Zamboanga del Sur

Cotabato City, Maguindanao

Butuan City, Agusan del Norte

Ten areas will experience 42 degrees Celsius heat index on Saturday:

Science Garden, Quezon City

NVSU Bayombong, Nueva Vizcaya

CLSU Munoz, Nueva Ecija

Tayabas City, Quezon 

Ambulong, Tanauan Batangas

Puerto Princesa City, Palawan

Daet, Camarines Norte

Masbate City, Masbate

Juban, Sorsogon

Mambusao, Capiz

Maasin, Southern Leyte

Dipolog, Zamboanga del Norte

On Friday close to 40 areas in different parts of the country actually logged heat indices of over 42 degrees which is categorized as dangerous.

PAGASA climatologist Dr. John Manalo said the possibility of more areas hitting heat indices of 42 degrees and higher in the next couple of weeks is highly likely. An area’s topography is among the reasons behind a higher heat index, he said.

“Low-lying areas like Tuguegarao, Dagupan, Aparri and some parts of Eastern Samar and Mindanao experience a higher heat index. Aside from low elevation, their distance to the coast, rivers and other bodies of water is also a factor,” he said.

The heat index takes into consideration an area's relative humidity.

“The higher the relative humidity, the higher the heat index.”

With a report by Raphael Bosano, ABS-CBN News