Devotees hear First Friday mass kn Quiapo Church in Manila on March 7, 2025, amid high temperatures in various parts of the country. Jonathan Cellona, ABS-CBN News/File

MANILA — The heat index may reach the “danger” level in 18 areas on Holy Wednesday, when thousands are expected to head home to their home provinces for the Semana Santa break, PAGASA said.

A measure of temperature and humidity, the heat index could reach the danger level of 42 to 51 degrees Celsius in the following areas, the state weather bureau said.

• Pasay City 
• Tuguegarao, Cagayan
• Echague, Isabela
• Baler, Aurora 
• Iba, Zambales
• Clark, Pampanga
• San Ildefonso, Bulacan
• Tarlac City
• Cavite City
• Tanauan, Batangas 
• Los Baños, Laguna
• Coron, Palawan 
• San Jose, Occidental Mindoro 
• Pili, Camarines Sur
• Iloilo City
• Dumangas, Iloilo 
• Catarman, Northern Samar
  
  

Among these areas, Los Baños, Laguna was expected to experience the highest heat index at 50 degrees Celsius. 

Under the “danger” level, prolonged exposure to sunlight could lead to heat cramps, heat exhaustion or heatstroke. 

Heat exhaustion or heatstroke: what to do in an emergency

Experts have reminded the public to stay hydrated, stay indoors or seek shade, and wear light clothing during hot weather. 

What to do when suffering from heatstroke, heat exhaustion
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