Surge in cyclones associated with ‘La Niña-like conditions’, PAGASA says


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Satellite image showing Typhoon Yinxing (Marce), Typhoon Nika (Toraji), and an unnamed tropical depression, which will be named Ofel once it enters the Philippine Area of Responsibility. (Courtesy of PAGASA)

Cyclone activity in the Philippines has increased in recent weeks, driven by “La Niña-like conditions” in the Pacific Ocean, said the climate monitoring chief of the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA).

In a press conference on Monday, Nov. 11, PAGASA Climate Monitoring and Prediction Section Chief Ana Liza Solis explained that while a “full-blown” La Niña has not yet developed, the current weather patterns closely resemble those typically seen during La Niña years.

“Hindi naman natin masasabi na rare ito dahil simula 1951, nakapagtala tayo ng mga pitong pagkakataon kung saan tatlo hanggang limang bagyo ang dumaan tuwing Nobyembre, at kadalasan sunod-sunod ito (This cannot be considered rare because since 1951, there have been about seven instances where three to five storms occurred in November, and these storms are usually consecutive),” Solis said.

She noted that the seven events were primarily linked to “weak” La Niña years.

Enhanced weather systems

Solis further explained that the recent cyclones have formed in the intertropical convergence zone (ITCZ), known as the “breeding ground” for tropical cyclones, which is more active due to La Niña-like conditions.

She added that La Niña is characterized by unusual cooling in the tropical Pacific, particularly in the central and eastern regions, along with unusual warming near the Philippine waters.

“Kahit hindi pa natin nararanasan ang full-blown La Niña, ang hindi karaniwang pag-init ng karagatang malapit sa Pilipinas ay nagiging favorable sa mga convective activity at pagbuo ng tropical cyclones (So, even though we are not experiencing a full-blown La Niña, the unusual warming of the ocean waters near the Philippines is creating conditions that are favorable for convective activity and the development of tropical cyclones),” Solis said.

She added that historically, weak La Niña years are associated with more intense tropical cyclones, reaching typhoon or super typhoon strength, during the last quarter of the year.

More severe weather events

According to the La Niña alert issued by PAGASA in July, Solis said it was predicted that the Philippines would experience increased rainfall during this period.

Aside from cyclones, she noted that other rain-bearing weather systems could contribute to “above-normal to way above normal” rainfall across the country.

While the rise in cyclone activity is not unprecedented, Solis urged the public to remain vigilant and prepare for more severe weather, as above-average rainfall is expected to continue through early 2025.

“Hindi man bagyo ang posible mag-contribute pa sa maraming pag-uulan na ito, so maraming other rain-bearing weather systems ay posible ring mas marami pang pag-ulan sa mga susunod na mga buwan (Even if it’s not a tropical cyclone, other weather systems may contribute to the heavy rainfall, so there could be more rainfall in the coming months),” she added.