PAGASA: 13 areas hit ‘danger’ heat index on Sunday; 10 areas on Monday

At least 13 areas in the country recorded “danger” level heat index on Sunday, with temperatures reaching as high as 45°C, while 10 areas are expected to experience the same levels on Monday, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).

Based on PAGASA’s 5 p.m. monitoring for April 26, the highest heat index was logged in Dumangas, Iloilo and Guiuan, Eastern Samar at 45°C.

Under PAGASA’s classification, a heat index of 42°C to 51°C falls under the “danger” category, where heat cramps and heat exhaustion are likely, while prolonged exposure may lead to heat stroke.

Also under the “danger” category on Sunday were:

• Sangley Point, Cavite City – 44°C
• Cuyo, Palawan – 44°C
• San Ildefonso, Bulacan – 43°C
• San Jose, Occidental Mindoro – 43°C
• Iloilo City – 43°C
• La Granja, La Carlota City, Negros Occidental – 43°C
• Baler, Aurora – 42°C
• Casiguran, Aurora – 42°C
• Iba, Zambales – 42°C
• Puerto Princesa City, Palawan – 42°C
• Roxas City, Capiz – 42°C
• Zamboanga City – 42°C

In Metro Manila, the heat index reached 41°C in NAIA, Pasay City and 40°C at Science Garden, Quezon City—both under the “extreme caution” category.

PAGASA advised the public to limit outdoor activities, drink plenty of water, and avoid strenuous physical exertion during peak afternoon hours as hot conditions persist.

What is the heat index?

The heat index refers to how hot it actually feels to the human body, combining air temperature and relative humidity. High humidity slows the evaporation of sweat, making it harder for the body to cool down.

PAGASA noted that heat index values may rise by as much as 9°C when exposed directly to sunlight.

The state weather bureau classifies heat index levels as follows:

• 27°C to 32°C (Caution): Fatigue is possible with prolonged exposure
• 33°C to 41°C (Extreme Caution): Heat cramps and heat exhaustion may occur
• 42°C to 51°C (Danger): Heat exhaustion is likely; prolonged exposure may lead to heat stroke
• 52°C and above (Extreme Danger): Heat stroke is highly likely and considered a medical emergency

The public is advised to regularly monitor PAGASA’s daily heat index forecasts.—MCG, GMA News