The southwest monsoon, locally known as “habagat,” may arrive earlier than usual, possibly by the end of May or during the first week of June, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said Tuesday.
During its 196th Climate Forum, PAGASA said the country is already shifting toward the habagat season, with conditions becoming more favorable for the onset of monsoon winds.
Joey Figuracion of PAGASA’s Climatology and Agrometeorology Division said the southwest monsoon typically begins between May 16 and the second week of June, but current forecasts indicate that it may arrive earlier this year.
“Based on our forecasts in the coming weeks, the southwest monsoon may arrive earlier. We may already experience habagat by late May, but the rainy season may only be felt by early June,” Figuracion said.
He clarified that the arrival of habagat does not automatically mean the official start of the rainy season.
PAGASA said it is also monitoring a low-pressure area outside the Philippine Area of Responsibility, which could enhance the southwest monsoon if it develops into a tropical cyclone in the coming days.
The weather bureau also warned that the developing El Niño may initially bring heavier rains over the western sections of the country by strengthening the southwest monsoon from June to September.
PAGASA senior weather specialist Remedios Ciervo said the country is now under an El Niño alert, with a 92 percent probability that the weather phenomenon will develop between June and August and persist until early 2027.
Based on PAGASA’s climate models, El Niño may intensify from September to November and could reach “very strong” status before the end of 2026.
While El Niño is usually linked to extreme heat and below-normal rainfall, PAGASA said it may first enhance monsoon rains, especially over the western sections of Luzon and the Visayas.
The agency also forecast that nine to 13 tropical cyclones may develop or enter the Philippine Area of Responsibility from June to November.
After the expected wetter conditions in the early phase of the southwest monsoon, PAGASA warned that dry spells and drought may develop from November until early 2027 as El Niño persists.
The weather bureau said a stronger El Niño does not automatically guarantee more severe impacts, but it raises the risk of drought, reduced rainfall, extreme heat, and agricultural losses.
PAGASA also cautioned that a very strong El Niño may affect water supply in dams and irrigation systems, particularly in areas dependent on rainfall for farming and domestic use.