The rains are here but hot and dry days may be expected because of El Niño possibly starting between June and July and lasting up to March, according to the Philippine weather bureau Pagasa. 

Elsewhere in the world, forecasters at the World Meteorological Organization (WMO) said temperatures are likely to soar and break records over the next five years, caused by El Niño and “fueled by heat-trapping greenhouse gases.” The WMO is the United Nations System’s authoritative voice on weather, climate and water.

Pagasa announced the onset of the rainy season in a statement last June 2, citing the widespread rains brought by scattered thunderstorms, Supertyphoon “Betty” (international name: “Mawar”) and the southwest monsoon (habagat) in recent days. 

Welcome news, but…

A graph of Pagasa puts the chance for rainfall to be above normal this June at 40-75%.

This is welcome news after torrid months when the heat index (or the measure of discomfort an average person experiences due to the combined effects of temperature and air humidity) soared to over 40°C, with a recorded high of 50°C.  

During these past months, Pagasa issued heat index information for levels ranging from caution (27 – 32°C), extreme caution (33 – 40°C) and danger (42 – 51°C) and possible dangers to health from continued heat exposure including exhaustion, cramps, and stroke. 

Pagasa said in its June 2 statement that with the start of the rainy season, it would suspend the daily issuance of heat index information starting on that day, to resume on March 1, 2024.

But the relief from hot days and nights may be short-lived or inconsistent. Pagasa also said “monsoon breaks”—or when rain events are followed by dry periods lasting for days or weeks—may occur.

Pagasa reiterated its El Niño Alert issued on May 2: that recent conditions and model forecasts indicated that El Niño may emerge in the coming season (June-July-August) at 80% probability and may persist until the first quarter of 2024. 

El Niño (a Spanish reference to the Christ Child because it was first observed in the month of December) is the warming of the water surface in the central and eastern tropical Pacific Ocean. 

Pagasa said El Niño indicators are warmer temperatures, weak winds coming from the east, and fewer clouds (and therefore less rain) over the Philippines.Thus, it increases the likelihood of below-normal rainfall conditions and possible dry spells and droughts in some parts of the country.

Related: Landslides in Leyte: Why the threat persists

‘We need to be prepared’

The impact of El Niño is expected to be global, and not merely confined to areas around the Pacific Ocean. 

“A warming El Niño is expected to develop in the coming months and this will combine with human-induced climate change to push global temperatures into uncharted territory,” said Prof. Petteri Taalas, secretary general of the WMO. 

He added: “This will have far-reaching repercussions for health, food security, water management and the environment. We need to be prepared.”  

According to a news update of the Geneva-based WMO last May 17, El Niño typically increases global temperatures in the year after it develops, in this case, 2024.

There is a 66% likelihood that the annual average near-surface global temperature between 2023 and 2027 will be more than 1.5°C above pre-industrial levels for at least one year.  

There is a 98% likelihood that at least one of the next five years, and the five-year period as a whole, will be the warmest on record.

Said Taalas: “This report does not mean that we will permanently exceed the 1.5°C level specified in the Paris Agreement which refers to long-term warming over many years. However, WMO is sounding the alarm that we will breach the 1.5°C level on a temporary basis with increasing frequency.”

Lowering global warming to pre-industrial levels is a long-term goal to “significantly reduce the risks and impacts of climate change.”  The 1.5°C reached in the period 1850-1900 has been used to represent the pre-industrial temperature. 

Limiting the global temperature rise is the global goal stated in the Paris Agreement, a legally binding international treaty on climate change adopted by 196 parties at COP21 in Paris on Dec. 12, 2015, and enforced on Nov. 4, 2016. 

Steady rise since 2015 

According to the WMO, the chance of temporarily exceeding 1.5°C has risen steadily since 2015, when it was close to zero.  Among the details in its report are:

• The average global temperature in 2022 was about 1.15°C, above the 1850-1900 average. The cooling influence of La Niña conditions over much of the past three years temporarily reined in the longer-term warming trend. But La Niña ended in March 2023 and El Niño is forecast to develop in the coming months.

• The annual mean global near-surface temperature for each year between 2023 and 2027 is predicted to be between 1.1°C and 1.8°C, higher than the 1850-1900 average. 

“Global mean temperatures are predicted to continue increasing, moving us farther and farther away from the climate we are used to,” said Dr. Leon Hermanson, an expert scientist who led the WMO report.

Predicted rainfall patterns vary from region to region worldwide. In its regional predictions, the WMO says that “near-surface temperatures in 2023 are likely to be higher than the 1991-2020 average in almost all regions except for Alaska, South Africa, South Asia and parts of Australia,” and that “parts of the South Pacific Ocean are likely to be cooler than average.”

Differing experiences

Similarly, certain parts of the Philippines may differ in their El Niño experience. It will be delayed in the areas affected by the southwest monsoon. The frequent heavy rainfall and humid weather brought by the habagat may reverse the less-rainfall pattern of El Niño.

In a public briefing on May 2, Ana Liza Solis, chief of Pagasa’s Climate Monitoring and Prediction Section, said there may be “above-normal” rainfall in the habagat-affected areas. 

El Niño’s warmer sea surface temperatures create favorable conditions for storms or typhoons.  Though many of these storms will likely dissipate before they hit the Philippines, or recurve around it, they may still enhance the effects of the habagat.

Hence, El Niño may be delayed in the regions affected by the habagat and may start later—in September or October—than in the rest of the country.  (The habagat period usually begins in June and ends around September or October.)  These regions include Cagayan Valley, Central Luzon, Cordillera Administrative Region, Mimaropa (Mindoro, Marinduque, Romblon, and Palawan) and Bicol.