A new tropical depression named ‘Isang’ has entered the Philippine area of responsibility on Friday morning, bringing moderate to heavy rains—along with the prevailing southwest monsoon or ‘habagat’—that triggered flash floods, according to the state weather bureau.
In its latest advisory, the Philippine Atmospheric Geophysical and Astronomical Services Administration (PAGASA) said ‘Isang’ was located in the coastal waters of Casiguran, Aurora as of 8:00 a.m. on August 22, 2025.
It was moving westward at 15 kilometers per hour (kph) with maximum sustained winds measured at 55 kph and gustiness of up to 75 kph. As this developed, PAGASA is also closely monitoring a low pressure area some 1,115 km east of southeastern Mindanao.
Forecasters warned of scattered rainshowers resulting in possible flash floods across Metro Manila, Ilocos Region, Cordillera Administrative Region, Cagayan Valley, Central Luzon and the provinces of Laguna, Quezon, Rizal, Camarines Norte and Camarines Sur.
As of 11:00 a.m., PAGASA issued heavy rainfall outlook estimated between 100 to 200 millimeters over La Union, Pangasinan, Benguet, Quirino, Nueva Vizcaya, Aurora, Zambales and Bataan due to the effects of ‘Isang.’
Communities within Metro Manila, Ifugao, Cagayan, Isabela, Nueva Ecija, Tarlac, Pampanga, Bulacan, Rizal, Laguna, Quezon, Camarines Norte, and Camarines Sur can expect 50 to 100 mm rainfall.
Several local government units in the National Capital Region (NCR) and other provinces outside of it have already suspended afternoon classes in both public and private schools amid the ongoing bad weather. The Metropolitan Manila Development Authority also reported incidents of flooding.
Weather conditions for the rest of Luzon, Visayas and Mindanao, meanwhile, will continue to be affected by the southwest monsoon, according to PAGASA. The rains in Occidental Mindoro, Cavite, Batangas, Marinduque, Romblon, Oriental Mindoro and Palawan are attributed to the ‘habagat.’
