The low-pressure area (LPA) east of Luzon has a high probability of developing into a tropical depression within 48 hours and will be named "Helen," according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
At around 3 p.m. on Monday, PAGASA estimated the location of the LPA at 90 kilometers (km) west-northwest of Calayan, Cagayan, and was already crossing the Balintang Channel.
Should it become a tropical depression, PAGASA will raise tropical wind Signal No. 1 over some areas in Northern Luzon, which automatically suspends maritime travel in these places.
Meanwhile, another LPA has formed at 315 km east-southeast of Hinatuan, Surigao del Sur on Monday afternoon.
Weather specialist Joey Figuracion said this LPA has a minimal chance of developing into a tropical depression as of Monday's forecast.
Ilocos Norte, Ilocos Sur, La Union, Pangasinan, Abra, Apayao, Benguet, Ifugao, Kalinga, Mountain Province, Batanes, Cagayan, Isabela, Nueva Vizcaya, Quirino, Oriental Mindoro, Occidental Mindoro, Marinduque, Palawan, Romblon, Aklan, Antique, Capiz, Guimaras, Iloilo, Negros Occidental, and Mindanao will experience scattered light to moderate to at times heavy rains due to the LPA and southwest monsoon or "habagat."
The rest of the country will have partly cloudy to cloudy skies with isolated rain showers mostly in the afternoon or evening.
PAGASA advised those in high-risk areas to take extra precautions against flooding and rain-induced landslides that may occur during heavy or prolonged rainfall.
The public and local disaster risk reduction and management offices concerned were also advised to monitor the rainfall/thunderstorm advisories and heavy rainfall warnings issued by PAGASA's regional services divisions for them to do the necessary precautionary measures.
"Helen" will be the eighth tropical cyclone this year, and fifth this month.
So far, the tropical cyclones that have entered or formed inside the Philippine area of responsibility this month were Dindo, Enteng, Ferdie, and Gener. None of these however have hit land.