By GMA News Published May 30, 2026 7:21pm + Add GMA on Google Make this your preferred source to get more updates from this publisher on Google. At least 39 areas will be under the "danger" level heat index on Sunday, May 31, 2026, the state weather bureau PAGASA said.According to PAGASA’s five-day heat index forecast on Saturday, the following areas may record "danger" heat index levels ranging from 42°C to 45°C:45°CBaler (Radar), AuroraCasiguran, AuroraCBSUA-Pili, Camarines SurBorongan, Eastern Samar44°CLaoag City, Ilocos NorteDagupan City, PangasinanTuguegarao City, CagayanIba, ZambalesSangley Point, Cavite City, CaviteAlabat, QuezonVirac (Synop), Catanduanes43°CNAIA Pasay City, Metro ManilaScience Garden, Quezon City, Metro ManilaSinait, Ilocos SurDMMMSU Bacnotan, La UnionAparri, CagayanCLSU Muñoz, Nueva EcijaSan Ildefonso, BulacanTAU Camiling, TarlacHacienda Luisita, Tarlac CityTayabas City, QuezonInfanta, QuezonMasbate City, MasbateJuban, SorsogonSurigao City, Surigao Del NorteHinatuan, Surigao Del SurButuan City, Agusan Del Norte42°CMMSU, Batac, Ilocos NorteCalayan, CagayanClark Airport (DMIA), PampangaCubi Pt., Subic Bay, Olongapo CityAmbulong, Tanauan, BatangasMulanay, QuezonNAS-UPLB, Los Baños, LagunaCalapan, Oriental MindoroDaet, Camarines NorteLegazpi City, AlbayCatarman, Northern SamarTacloban City, LeyteMeanwhile, the following areas in Benguet are forecast to experience "not hazardous" heat index levels:Baguio City - 25 °CBSU La Trinidad, Benguet - 25 °CBenguet Radar, Tuba, Benguet - 20 °CThe heat index refers to the temperature felt by the human body when relative humidity is combined with actual air temperature. High humidity slows the evaporation of sweat, making it more difficult for the body to cool down.PAGASA advised the public to limit their time outside, and use umbrellas or caps when outdoors. The state weather bureau also recommended drinking lots of water and avoiding intake of tea, coffee, and sodas. — Lyjah Tiffany Bonzo/VBL, GMA News