PH temperatures exceed forecasts in April, but May will be even hotter — PAGASA

Temperatures in various areas across the Philippines have already surpassed government projections for the month of April, but weather service PAGASA warned that the hottest days have yet to come in May.

The year's highest maximum daytime temperature so far was registered on Tuesday in Echague, Isabela at 40°C — exceeding the 39.7°C forecast for Northern Luzon, according to Maki Pulido's report on Unang Balita.

In Camiling, Tarlac, thermometers hit 39.6°C, eclipsing the 39.4°C projection for lowland Luzon.

Metro Manila has also recorded its highest temperature of the year, the Unang Balita report added. Last Tuesday, it reached 36.9°C at the Ninoy Aquino International Airport (NAIA) area in Pasay City, hotter than the 36.8°C forecast.

While the sweltering heat has already triggered adjustments in face-to-face classes and government work schedules, PAGASA said temperatures may peak in next month.

"As early as April, nararamdaman natin so ibig sabihin possible pa po na higher than 40° [Celsius] na possible in terms of maximum daytime temperature," said Ana Liza Solis, chief of PAGASA's Climate Monitoring and Prediction Section.

(We have been feeling the heat as early as April, so that means it's possible that we'll have maximum daytime temperatures of more than 40°C.)

Worse, PAGASA warned that there was a 50-50 chance that May's maximum daytime temperatures would rise to a scorching 42.2°C.

For comparison, Wednesday's highest projected temperature in Metro Manila was 34°C, based on PAGASA's tracking at the Port Area in Manila City.

Extreme danger heat index

However, weather specialist Dr. John Manalo on Wednesday told GMA Integrated News that some areas of the country may reach extreme danger levels, or temperatures at 52°C or higher, next month.

"Marami na po 'yung mga lugar sa ating bansa na nakaka-experience ng danger category when it comes to heat index. And then 'yung possibility na magkaroon pa tayo ng extreme danger ay nandito po as we approach the month of May," Manalo said.

(We already have many areas in the country experiencing the danger category when it comes to heat index. And then there's the possibility that we reach extreme danger levels now that we are approaching the month of May.)

"May possibility po ha. Pero hindi po tayo 100% certain (There is a possibility, but we are not 100% certain)," Manalo stressed.

Manalo said the highest heat index values are usually recorded in May.

"During month of May, tumataas na rin po ang relative humidity. Dahil papunta, towards ano na po tayo rainy season so 'yung moisture content ng hangin ay mas dumarami na rin as compared sa April and March which is also dry," he said.

(Relative humidity also rises during the month of May. This is because we are moving towards the rainy season, so the moisture content of wind is increasing compared to April and March, which are also dry.)

When asked what places may record extreme danger heat index levels, Manalo replied: "'Yung mga lugar na low-lying areas. Actually, 'yung mga tinitingnan natin bukod sa Aborlan (Palawan) na top today, ay meron pa pong minsan nagta-top din 'yung Dagupan, Pangasinan. 'Yung Tuguegarao (Cagayan.) Meron din tayo sa Samar sa Eastern Visayas natin, at ilang lugar din po sa Mindanao."

(Low-lying areas. Actually, aside from Aborlan in Palawan which is on top of our list, we have other areas that occasionally take the top spot like Dagupan, Pangasinan and Tuguegarao, Cagayan. The same can be seen in Samar, Eastern Visayas, and other parts of Mindanao.

Topography, location

Manalo said topography was a big factor, adding that, "Halimbawa 'yung Tuguegarao, napapalibutan siya ng mountains tapos 'yung elevation niya ay relatively lower as compared doon sa high, elevated locations natin tulad ng Baguio."

(For example, Tuguegarao is surrounded by mountains while its elevation is relatively lower compared to high, elevated locations like Baguio.)

"Bukod po doon ay 'yung mga stations din po natin na malapit sa bodies of water, 'yung mga malapit sa coastlines dahil doon po mataas 'yung relative humidity. Again, isa po 'yung relative humidity sa ingredients para tumaas 'yung heat index," he added.

(Also, our stations near bodies of water and coastlines [are at risk of reaching extreme danger levels] because relative humidity is high in these places. Again, relative humidity is an ingredient to cause the heat index to rise.)

Manalo warned that if the heat index reaches 52°C and beyond, there was a big possibility that the vulnerable population, including the elderly and those with existing health conditions, would experience heat stroke.

The heat index in Metro Manila on Tuesday, April 16, was at 40°C to 41°C. It registered at 46°C in Aborlan, Palawan; and 44°C in Ambulong, Tanauan, Batangas and Puerto Princesa City, Palawan.

Dangerous highs on Wednesday

Many Filipinos were in for a hot day anew on Wednesday as the heat index in 17 areas was expected to hit dangerous highs.

Heat index is the measure of the temperature that a person feels, which is different from the actual air temperature, according to PAGASA. It is computed by factoring in the humidity as well as air temperature.

Dangerous level heat index is from 42°C to 51°C, where heat cramps and heat exhaustion are likely. Heat stroke is also possible with continued exposure.

PAGASA advises the public to prevent heat-related illnesses by doing the following:

• Limit the time spent outdoors
• Drink plenty of water
• Avoid tea, coffee, soda, and liquor
• Wear umbrellas, hats, and sleeved clothing outdoors
• Schedule heavy-duty activities for the beginning or end of the day when it's cooler.

Hot, humid weather

In its 4 p.m. bulletin on Wednesday, PAGASA reported that the ridge of a high-pressure area (HPA) extending over the eastern sections of Northern and Central Luzon would continue to bring hot and humid weather over the country.

"Kapag ridge ng HPA ang nakakaapekto sa isang specific na lugar, asahan natin ang mas mababang cloud development, mas mababang rainfall, resulting to higher temperatures sa areas na 'yan," PAGASA weather specialist Veronica Torres reported.

(If the ridge of an HPA is affecting a specific area, we can expect lower cloud development, low rainfall, resulting to higher temperatures in these areas.)

As for its 24-hour forecast, PAGASA said partly cloudy to cloudy skies with isolated rainshowers or thunderstorms were expected over Metro Manila and the rest of the country due to the localized thunderstorms.

Light to moderate winds and slight to moderate coastal water condition, meanwhile, are expected over the country's seaboards.

Sunrise in Metro Manila on Thursday will be at 5:41 a.m. — with reports from Tina Panganiban-Perez and Sundy Locus/ VDV, GMA Integrated News