MANILA, Philippines -- At least nine cities in the National Capital Region have been placed under Signal No. 1, along with other areas in Luzon as Tropical Depression "Gener" continues to maintain its strength, the state-run weather agency said on Tuesday. The Philippine Atmospheric Geophysical and Astronomical Services Administration (Pagasa) said that the storm signal was raised over the northern portion of Metro Manila (Quezon City, Caloocan City, Valenzuela City, Malabon City, Navotas City, Marikina City, City of Manila, San Juan City and Mandaluyong City). Also under Signal No. 1 are Cagayan, including Babuyan Islands, Isabela, Quirino, Nueva Vizcaya, Apayao, Kalinga, Abra, Ifugao, Mountain Province, Benguet, Ilocos Norte, Ilocos Sur, La Union, Pangasinan, Zambales, Tarlac, Nueva Ecija, Pampanga, Bulacan, the northern and central portions of Bataan (Dinalupihan, Orani and Hermosa), Aurora, the northern portion of Quezon (General Nakar and Infanta) including Polillo Islands and the northern portions of Rizal (Rodriguez and San Mateo). Tracked over the vicinity of Alicia, Isabela, Gener is moving westward at 30 kilometers per hour (kph) with maximum sustained winds of 55kph near the center and gustiness of up to 70kph, the state weather bureau said. Forecast to emerge over the coastal waters of Ilocos Sur or La Union anytime in the day, the tropical cyclone will then move generally westward over the West Philippine Sea until Thursday before turning west-northwestward as it heads towards southern China. Gener will likely exit the Philippine Area of Responsibility between Tuesday night and Wednesday morning, said Pagasa in its 5 a.m. bulletin.