The monsoon trough, which is causing rains over some parts of the country in the past few days, may continue to affect Luzon and Western Visayas in the next 24 hours, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said on Sunday, June 13.

The rain-inducing weather system is the portion of the intertropical convergence zone or ITCZ that is connected to the monsoon system or "habagat," containing circulations or low pressure systems.

It is a typical source of tropical cyclones in the Western North Pacific from June to September.

In the next 24 hours, scattered rain showers and thunderstorms are more likely over Zambales, Bataan, Cavite, Batangas, Oriental Mindoro, Occidental Mindoro, Marinduque, Romblon, Palawan, Aklan, Antique, Capiz, Guimaras, Iloilo, and Negros Occidental.

PAGASA advised those in these areas to remain vigilant against possible flash floods or landslides due to moderate to at times heavy monsoon rains.

The combined effects of the monsoon trough and ITCZ may also bring isolated rain showers or thunderstorms over Metro Manila and the rest of the country.

There is also a possibility of flash floods or landslides in these areas due to severe thunderstorms in the afternoon or evening, PAGASA warned.

As of Sunday, weather specialist Loriedin dela Cruz said PAGASA is not expecting a low pressure area or tropical cyclone that may enter or form inside the Philippine area of responsibility within two to three days.

Moreover, PAGASA has not issued a gale warning due to slight to moderate seas across the country's coasts thus fisherfolk and those using small seacraft are safe to sail.

However, the State weather bureau still advised fisherfolk and seafarers to observe caution during severe thunderstorms, which are most often accompanied by strong winds and could trigger big waves.