PAGASA raises orange warning over NCR, warns of intense rain. A PAGASA satellite image as of 8:32 a.m. Thursday shows a southwest monsoon affecting Luzon. Moderate to heavy rainfall is expected as the Rainfall Warning System is changed to orange. The rainfall warning levels are now 'yellow, orange, red,' the colors associated with awareness, preparedness and emergency. GMA News

An weather disturbance – approaching low-pressure area (LPA) – that could again enhance the southwest monsoon moved closer to northern Luzon early Saturday and may enter Philippine territory in 12 to 24 hours, state weather forecasters said.

The Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) also warned of flash floods and landslides on Northern and Central Luzon.

"Papalapit na ito sa ating boundary ng Philippine area of responsibility. Asahan natin sa susunod na 12 hanggang 24 oras, papasok na ito sa PAR," PAGASA forecaster Fernando Cada said in an interview on dzBB radio.

As of 2 a.m., the LPA was estimated at 1,370 km east of Northern Luzon, PAGASA said in its 5 a.m. forecast.

Cada did not say if the LPA would become a cyclone while in Philippine territory. If the LPA intensifies into a cyclone, it would be locally codenamed "Helen."

But he said there is a possibility the LPA may enhance the southwest monsoon once it gets closer to Philippine territory.

"Maaring makaimpluwensya uli ito sa susunod na araw sa ating habagat (It can influence the monsoon in the coming days)," he said.

For now, Cada said the southwest monsoon is the prevailing weather system in the country, and is affecting mainly Northern and Central Luzon.

In Metro Manila, which is still reeling from days of heavy rain and floods, Cada said rain will be likely in the afternoon and evening.

"Mataas ang probability ng ulan sa hapon o gabi. Yan ang time na ang habagat ay nagbibigay ng ulan sa Luzon at Metro Manila," he said.

Flash floods, landslides

PAGASA's 5 a.m. bulletin said Northern and Central Luzon will experience mostly cloudy skies with scattered rain showers and thunderstorms becoming cloudy with widespread rain over the western section, which may trigger flashfloods and landslides.

The rest of the country will be partly cloudy to cloudy with isolated rain showers and thunderstorms, he added.

Moderate to strong winds blowing from the southwest will prevail over Northern and Central Luzon and the coastal waters along these areas will be moderate to rough.

Elsewhere, winds will be light to moderate coming from the south to southwest with slight to moderate seas. — LBG, GMA News