The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said there is a 55 percent probability of the La Niña phenomenon occurring during the October-December period, based on its monthly climate assessment released on Tuesday, July 9.

PAGASA added that there is a possibility of a sustained La Niña until the first quarter of 2025.

Since March, PAGASA has maintained a La Niña Watch under its alert system due to potential La Niña development.

Currently, the tropical Pacific region is experiencing El Niño Southern Oscillation-neutral (ENSO-neutral) conditions—where neither El Niño nor La Niña exists. 

These conditions are expected to persist until the August-September-October 2024 season before the potential onset of La Niña.

PAGASA may upgrade the La Niña Watch to a La Niña Alert as the probability of the climate phenomenon increases under its ENSO alert system. 

During its climate forum on June 26, PAGASA-Climate Monitoring and Prediction Section Chief Ana Liza Solis said there is a likelihood of a weak and short-lived La Niña, with the possibility of La Niña-like conditions if it fails to materialize, toward the end of the year.

During the forum, she said there was a 50 percent chance that La Niña would occur by September.

PAGASA said La Niña increases the likelihood of above-normal rainfall, which could cause adverse effects, such as heavy rains, floods, flash floods, and landslides in vulnerable areas.

Outlook for July

PAGASA said various weather systems would influence the country this month, including the southwest monsoon or “habagat,” easterlies, ridge of high pressure area, localized thunderstorms, intertropical convergence zone, low pressure areas, shearline, frontal system, and the potential development of entry of two or three tropical cyclones into the Philippine area of responsibility.

Likewise, rainfall forecasts for July show below-normal conditions across most parts of Luzon and Eastern Visayas. 

However, near-normal conditions are expected in most areas of Mindanao, except for Davao del Sur and Davao Occidental where above-normal conditions are likely. 

PAGASA also said the probabilistic rainfall forecast indicates a high likelihood of below-normal conditions in Luzon and Visayas, and above-normal conditions in Mindanao. 

Moreover, generally near-average to above-average surface air temperatures are expected in most parts of the country this month except in some parts of MIMAROPA (Oriental Mindoro, Occidental Mindoro, Marinduque, Romblon, Palawan) and Bicol Region where slightly below-average to below-average temperatures are predicted. 

The forecast temperature ranges are as follows: Metro Manila (20.5⁰C-37.0⁰C); mountainous areas of Luzon (14.0⁰C-27.5⁰C); the rest of Luzon (17.0⁰C-38.5⁰C); Visayas (20.0⁰C-36.5⁰C); mountainous areas of Mindanao (16.0⁰C-33.0⁰C); and the rest of Mindana (20.5⁰C-36.5⁰C).