By Darryl John Esguerra | May 18, 2025

MANILA – The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) forecasts rain showers over parts of the country on Sunday due to the intertropical convergence zone (ITCZ) and easterlies.

In its 24-hour public weather forecast issued at 4 a.m., PAGASA said the ITCZ will affect Mindanao, while easterlies will influence weather conditions in the rest of the country, including Metro Manila.

Cloudy skies with scattered rain showers and thunderstorms are expected over Mindanao, Eastern Visayas, and Palawan due to the ITCZ.

Meanwhile, Metro Manila and the rest of the country will experience partly cloudy to cloudy skies with isolated rain showers or thunderstorms brought about by easterlies.

The agency advised the public to be alert for possible flash floods or landslides during severe thunderstorms.

Light to moderate winds from the east to southeast will prevail over Luzon, while winds from the east to northeast will affect Visayas and Mindanao.

Coastal waters across the country will be slight to moderate, ranging from 0.6 to 1.8 meters.

Heat index

Meanwhile, PAGASA, in its 5 p.m. May 17 forecast, warned of dangerous heat index levels in 24 areas on Sunday.

The highest heat index forecast is recorded in Aparri, Cagayan with a sizzling 45°C.

This, along with 23 other locations, falls under “danger” classification for heat index, which ranges from 42°C to 51°C, according to PAGASA.

Areas forecast to reach dangerous heat index levels include:

• NAIA Pasay City – 42°C

• Sinait, Ilocos Sur – 42°C
• Laoag, Ilocos Norte – 44°C
• Dagupan City, Pangasinan – 44°C

• MMSU, Batac, Ilocos Norte – 43°C
• Bacnotan, La Union – 42°C
• Calayan, Cagayan – 42°C

• Aparri, Cagayan – 45°C
• Tuguegarao City, Cagayan – 43°C
• Baler, Aurora – 43°C

• Iba, Zambales – 42°C
• Cubi Point, Subic Bay, Olongapo City – 42°C
• TAU, Camiling, Tarlac – 44°C

• Sangley Point, Cavite – 43°C
• Infanta, Quezon – 42°C
• San Jose, Occidental Mindoro – 42C
• Daet, Camarines Norte – 43°C
• Legazpi City, Albay – 42°C
• Virac, Catanduanes – 43°C
• Masbate City, Masbate – 42°C

• CBSUA-Pili, Camarines Sur – 42°C
• Iloilo City, Iloilo – 42°C

• Catarman, Northern Samar – 43°C
• Borongan, Eastern Samar – 42°C

Heat index refers to the temperature felt by the human body when relative humidity is factored in with actual air temperature.

The weather bureau advised the public to limit the time spent outdoors, especially at noon, and drink plenty of water.

People going outdoors are reminded to use umbrellas or wear hats and sleeved clothing. (PNA)