manila: Nika, internationally known as Toraji, has escalated into a typhoon with maximum sustained winds reaching 120 kilometers per hour (kph) near its center and gustiness up to 150 kph, as reported by the weather bureau in its 5 a.m. bulletin on Monday. The typhoon was located approximately 100 km east southeast of Casiguran, Aurora as of 4 a.m. According to Philippines News Agency, Tropical Cyclone Wind Signal (TCWS) No. 4 has been raised over the northernmost part of Aurora, along with significant portions of Isabela, southeastern Abra, central and eastern Mountain Province, eastern Ifugao, and western and southern sections of Kalinga. Residents in these areas are expected to experience typhoon-force winds. Regions under TCWS No. 3, including the northern part of Aurora, northeastern Nueva Vizcaya, northern Quirino, the remainder of Isabela, southwestern Cagayan, the rest of Abra, southern Apayao, the rest of Kalinga, Mountain Province, Ifugao, northern Benguet, southern Ilocos Norte, and Ilocos Sur, w ill encounter storm-force winds. Gale-force winds are anticipated in areas covered by TCWS No. 2, which spans the central portion of Aurora, the rest of Nueva Vizcaya, Quirino, and sections of Cagayan, Apayao, Benguet, Ilocos Norte, La Union, northeastern Pangasinan, and northern Nueva Ecija. Areas under TCWS No. 1, including the rest of Aurora, Cagayan including Babuyan Islands, Pangasinan, Nueva Ecija, Bulacan, Pampanga, Tarlac, parts of Zambales, Metro Manila, Rizal, eastern Laguna, northern and eastern Quezon including Polillo Islands, Camarines Norte, and northeastern Camarines Sur, will experience strong winds. "There is a moderate to high risk of storm surge that may occur in the next 48 hours in the low-lying or exposed coastal localities of Ilocos Norte, Ilocos Sur, La Union, Pangasinan, Cagayan including Babuyan Islands, Isabela, Zambales, Aurora, Quezon including Polillo Islands, Camarines Norte, Camarines Sur, and Catanduanes," stated the Philippine Atmospheric, Geophysical and Astronomical Ser vices Administration (PAGASA). PAGASA has also issued a gale warning for the eastern seaboard of Luzon and the northern and western seaboards of Northern Luzon. Meanwhile, PAGASA anticipates that Typhoon Nika will make landfall over Isabela or northern Aurora on Monday and warns of potential intensification before landfall.