Casiguran, Aurora, logged the highest-ever heat index in the country at 60 °C on Monday, the Philippine Atmospheric Geophysical and Astronomical Services Administration (Pagasa) reported.

The town's heat index could make heat stroke "imminent," as it falls under the "extreme danger" category, according to Pagasa.

This is also the fourth day in a row that the area has recorded temperatures above 52°C, the threshold for the "extreme danger" category.

On August 11 and 12, the heat index in the area reached 59 degrees Celsius.

The heat index predicted that an average person will experience level of discomfort as a result of the combined impacts of temperature and air humidity.

The weather bureau declared the commencement of El Niño in early July, raising the risk of below-normal rainfall conditions, which could result in negative consequences such as "dry spells" or droughts in various parts of the country.