The southwest monsoon, enhanced by severe tropical storm Nanmadol, will continue to bring cloudy skies with scattered rain showers and thunderstorms over most parts of the Philippines in the next 24-hour period, the state weather bureau warned on Thursday, Sept. 15.

Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) weather specialist Benison Estareja said severe tropical storm Nanmadol is not directly affecting the country, but he also warned that the weather disturbance may further enhance the southwest monsoon, locally called “habagat.”

“Ang nakakaapekto instead ay yung habagat o southwest monsoon na siyang pinalalakas nitong si Nanmadol at nagpapaulan po ito sa malaking bahagi ng Southern Luzon, Visayas, western section of Mindanao (What affects the country instead is the southwest monsoon which is strengthened by Nanmadol. It will bring rains in most parts of Southern Luzon, Visayas, and the western section of Mindanao),” said Estareja in a public weather forecast.

Due to the Nanmadol-enhanced southwest monsoon, cloudy skies with scattered rain showers and thunderstorms may prevail in Zambales, Bataan, Occidental Mindoro, Palawan, Aklan, Antique, Negros Occidental, Zamboanga Peninsula, Basilan, Sulu, and Tawi-Tawi.

Residents of these areas were warned against possible flash floods and landslides that may occur during moderate to heavy rains.

Metro Manila and the rest of the country, on the other hand, may experience partly cloudy to cloudy skies with isolated rain showers due to the southwest monsoon and localized thunderstorms.

'Nanmadol' to be given the local name 'Josie'

Meanwhile, as of 5 a.m., Nanmadol intensified into a severe tropical storm.

It was last spotted 1,830 kilometers (km) east of extreme northern Luzon outside the Philippine area of responsibility (PAR) with maximum sustained winds of 95 kilometers per hour (kph) and gustiness of up to 115 kph.

It is moving west northwestward at 15 kph and is expected to enter PAR tonight, Sept. 15 or tomorrow morning, Sept. 16. Once inside PAR, it will be given the domestic name Josie.

“ is forecast to remain far from the Philippine landmass and not directly affect the weather condition in the country. However, it may enhance the southwest monsoon within the forecast period,” said the state weather bureau.