Ingat, Dagupeños. It's going to be a sizzling hot Tuesday in Dagupan City with a forecasted 49 degrees Celsius on the heat index, after hitting 51 degrees Celsius on Monday.

State weather bureau PAGASA warned Monday of possibly even hotter weather in the month of May despite "weakening" of the El Niño phenomenon. PAGASA Weather Specialist John Manalo said in a televised briefing that based on previous data, hottest temperatures in the country are usually recorded in May.

Expect hotter weather in May despite 'weakening' El Niño, says PAGASA

According to PAGASA's latest heat index forecast, Aparri, Cagayan is facing a record heat index temperature of 47 degrees Celsius for a second straight day while Tuguegarao City in Cagayan is facing 46 degrees Celsius.

Six areas are facing 45-degrees Celsius heat index on Tuesday: Laoag City, Ilocos Norte; Bacnotan, La Union; Iba, Zambales; Coron, Palawan; Aborlan, Palawan; and CBSUA-Pili, Camarines Sur.

Nine areas are facing 44-degrees Celsius heat index on Tuesday: Sinait, Ilocos Sur; ISU Echague, Isabela; CLSU Munoz, Nueva Ecija; Baler, Aurora; Cubi Pt., Subic Bay, Olongapo City; San Jose, Occidental Mindoro; Virac, Catanduanes; Iloilo City and Dumangas, Iloilo.

Other areas facing extreme heat index on Tuesday are:

NAIA Pasay City, Metro Manila - 42 degrees C

Science Garden Quezon City, Metro Manila - 42 degrees C

MMSU, Batac, Ilocos Norte - 43 degrees C

Calayan, Cagayan - 42 degrees C

NVSU Bayombong, Nueva Vizcaya - 42 degrees C

Clark Airport (DMIA), Pampanga - 43 degrees C

Casiguran, Aurora - 43 degrees C

Sangley Point, Cavite - 42 degrees C

Ambulong, Tanauan, Batangas - 42 degrees C

Puerto Princesa City, Palawan - 43 degrees C

Date, Camarines Norte - 42 degrees C

Legazpi City, Albay - 42 degrees C

Masbate City, Masbate - 43 degrees C

Roxas City, Capiz - 43 degrees C

Mambusao, Capiz - 43 degrees C

La Granja, La Carlota, Negros Occidental - 43 degrees C

Catarman, Northern Samar - 42 degrees C

Catbalogan, Samar - 42 degrees C

Tacloban City, Leyte - 42 degrees C

Guiuan, Eastern Samar - 43 degrees C

Zamboanga City, Zamboanga del Sur - 43 degrees C

Baguio City remains the area with the coolest temperatures at 28 degrees Celsius, followed by BSU, La Trinidad in Benguet at 29 degrees Celsius.

An Intertropical Convergence Zone (ITCZ), meanwhile, is affecting southern Mindanao, bringing cloudy skies with scattered rainshowers and thunderstorms to Davao Region, Surigao del Sur, South Cotabato, Sultan Kudarat, Sarangani, Zamboanga del Sur, Zamboanga Sibugay, Basilan, Sulu, and Tawi-Tawi.