Park goers cool off under a new outdoor misting system installed inside the Quezon Memorial Circle in Quezon City. — PHILIPPINE STAR/MIGUEL DE GUZMAN

A majority of monitoring areas are expected to register danger-level heat index on Thursday, with temperatures reaching 47 degrees Celsius in two areas, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).

Of the 78 monitoring stations nationwide, 50 are likely to experience danger-level heat index ranging from 42°C to 51°C, according to the latest heat index report.

Hinatuan, Surigao del Sur and Butuan City, Agusan del Norte are projected to record the highest heat index at 47°C.

These are followed by Tarlac Agricultural University (TAU) and Borongan, Eastern Samar at 45°C.

Other monitoring stations in key cities are also expected to experience danger-level heat index, including NAIA in Pasay City at 43°C and Science Garden in Quezon City at 42°C, representing the National Capital Region.

Clark Airport, Pampanga is expected to record 43°C, Iloilo City at 44°C, and Davao City, Davao del Sur at 42°C.

On Friday, most areas are also expected to experience danger-level heat index, with 45°C projected in several areas.

Heat index refers to the “feels like” temperature that combines air temperature and humidity to measure how hot it feels to the human body.

PAGASA warned that danger-level heat index may cause heat cramps and heat exhaustion, and even heat stroke with prolonged exposure.

To avoid such risks, a medical expert on Thursday recommended staying hydrated and avoiding excessive sun exposure, especially among vulnerable sectors such as workers, children, the elderly, and people with comorbidities.

So dapat yung hydration is corresponding sa amount of work being done [Hydration should correspond to the amount of work being done],” Dr. Abdul Javar Esturco, medical specialist II and safety and environment unit head at Zamboanga City Medical Center, said during a press conference organized by the Health Reporters Organization (HeRO) on Thursday.

The World Health Organization recommends drinking at least two to three liters of water per day, or roughly one cup every hour, to help prevent heat exhaustion. — Edg Adrian A. Eva