SEVERAL provinces in extreme northern Luzon were placed under Tropical Cyclone Wind Signal (TCWS) Number 1 on Friday morning, August 22, 2025, due to Tropical Depression Isang.
In its 11 a.m. weather advisory, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) said the following areas were under TCWS 1:
Batanes
Cagayan
Isabela
Quirino
Nueva Vizcaya
Apayao
Kalinga
Abra
Mountain Province
Ifugao
Benguet
Ilocos Norte
Ilocos Sur
La Union
Pangasinan
The northern and central portions of Aurora (Casiguran, Dinalungan, Dilasag, Baler, Maria Aurora, Dipaculao, San Luis)
The northern portion of Nueva Ecija (Lupao, Carranglan, Pantabangan, San Jose City)
As of 10 a.m., Isang was spotted in the vicinity of Casiguran, Aurora, packing maximum sustained winds of 55 kilometers per hour (km/h) near the center, gusts of up to 90 km/h, and a central pressure of 1002 hPa.
It was moving westward at 15 km/h.
“The wind signals warn the public of the general wind threat over an area due to the tropical cyclone. Local winds may be slightly stronger/enhanced in coastal and upland/mountainous areas exposed to winds. Winds are less strong in areas sheltered from the prevailing wind direction,” the weather bureau said.
Pagasa said Zambales, Bataan, Metro Manila, Calabarzon, Mimaropa, Camarines Norte, Camarines Sur, Catanduanes, Burias Island, Western Visayas, Negros Island Region, Central Visayas, Dinagat Islands, Southern Leyte, Surigao del Norte, and Camiguin may also experience the effects of Isang in the coming days despite not being under a TCWS.
On Friday, Isang will affect Batanes, Cagayan, Ilocos Region, Cordillera Administrative Region, Zambales, Bataan, Tarlac, Pampanga, Bulacan, Metro Manila, Cavite, Rizal, Palawan, Occidental Mindoro, Romblon, Burias Island, and Camarines Sur.
Isang is expected to exit the Philippine area of responsibility by Saturday morning or afternoon, August 23.
“Isang is forecast to intensify into a tropical storm tomorrow morning and may reach severe tropical storm category while approach the waters south of Hainan, China. However, intensification into a tropical storm at a much earlier time (e.g., several hours after emerging over the West Philippine Sea) is not ruled out,” said Pagasa. (TPM/SunStar Philippines)