MANILA -- The extreme hot weather that parts of the country are experiencing may last until May, a climatologist told the Philippine News Agency (PNA) on Thursday. 

"We're experiencing cloudiness, and the dryness in the environment is high. We expect that we will continue experiencing extreme hot weather until May," said Annalisa Solis, climate monitoring officer-in-charge of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). 

Solis added that PAGASA has recorded a heat index (HI) of 51.5 degrees Celsius in Dagupan recently. Thus, they are also expecting to record an HI of more than 50 degrees Celsius in the coming days.

Solis explained that the HI is different from temperature.  

"Note that there are areas with high temperature but have a low HI. For example, Calapan, Mindoro recently had the highest HI at 46 degrees Celsius. But on that day, Isabela had the highest temperature at 39.7 degrees Celsius," she said. 

The HI, she explained, is being computed based on the temperature and humidity in an area, and how the sultriness affects the human body. 

For PAGASA, an HI of 41 degrees to 54 degrees Celsius is considered dangerous.  

"If a person would stay outdoors and continue outdoor activities, he or she might suffer from heat stroke," Solis remarked. 

Heat cramps and heat exhaustion are also possible, according to PAGASA.  

Those in areas with an HI of 27 degrees to 32 degrees Celsius must be cautious. Fatigue and heat cramps are possible from continued exposure and activity. 

An HI reaching more than 54 degrees Celsius is considered extremely dangerous, as heat stroke is imminent, PAGASA added. 

Meanwhile, Solis said the hot temperature may be attributed to having no clouds at day time, as this would lead to the person's direct exposure from the sun.

"Having no clouds during day time, then having cloudy skies at night cause hot temperature," she said.

PAGASA's tips 

PAGASA posted on its website some tips on how to deal with high HI: 

1. Stay indoors as much as possible. If air conditioning is not available, stay on the lowest floor out of the sunshine. 

2. Wear lightweight and light-colored clothing. Light colors will reflect the sun's energy. 

3. Drink plenty of water regularly. The body needs water to keep cool. 

4. Water is the safest liquid to drink during heat emergencies. Avoid drinking liquor because it dehydrates the body. 

5. Eat small meals but eat more often. Avoid food high in protein, as they can increase metabolic heat. (PNA)