A new and third low pressure area (LPA) was spotted outside the Philippine area of responsibility (PAR), the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) reported Monday.

According to PAGASA, the third LPA has a "medium" potential of developing into a tropical depression within the next 24 hours.

Meanwhile, the first LPA, located 1,140 kilometers (km) east of Central Luzon, has a "high" chance of developing into a tropical depression within the next 24 hours.

On the other hand, the second LPA observed 225 km east southeast of Basco, Batanes, also has a "medium" chance of developing into a tropical depression within the next 24 hours.

Red rainfall warning is hoisted for Metro Manila, Bataan, and parts of Cavite (including Bacoor, Dasmarinas, Kawit, Imus, and General Trias) due to the intensified southwest monsoon (habagat).

Serious flooding is expected in flood-prone areas.

An orange warning, meanwhile, is in effect for Rizal, Batangas, Laguna, Batangas, Zambales, Pampanga, Bulacan, and southern Cavite towns, while a yellow warning has been raised in Nueva Ecija, Tarlac, and Quezon with flooding still possible.