of Yap in the Caroline Islands, the depression intensified into a tropical storm according to the JTWC, which gave it the name Zeb. The JMA again was delayed in upgrading by a day. After becoming a tropical storm, Zeb proceeded to steadily intensify. Its large inflow spawned a circulation well to the east-northeast, which organized into a separate tropical storm – Alex. Early on October 11, the storm entered the area of responsibility of PAGASA – the Philippine-based weather agency – which gave it the local name Iliang. Late on October 11, the JTWC upgraded Zeb to typhoon status, or one-minute winds of at least . This was based on the appearance of a banding-type eye on satellite imagery. On October 12, the storm rapidly intensified as it turned more to the west-northwest toward the Philippines. During this time, it caused increased wind shear over the smaller Tropical Storm Alex to the east-northeast, ultimately absorbing it. At 00:00 UTC on October 13, the JTWC upgraded Zeb to super typhoon status, estimating winds of , marking that Zeb attained Category 5 status on the Saffir-Simpson scale. Twelve hours later, the agency estimated that the typhoon strengthened further to a peak of 285 km/h (180 mph), making it the strongest storm of the season. At the same time, PAGASA also estimated peak 10-minute winds of , also designating Zeb as a super typhoon. Late on October 13, the JMA estimated peak 10-minute winds of just east of the island of Luzon. While near peak intensity, the JTWC estimated that winds of extended , and gales extended from the center. Zeb's eyewall continued to contract up until it moved ashore. Early on October 14, Zeb made landfall on eastern Luzon just south of Palanan Bay, or east of Ilagan, near peak intensity. The typhoon weakened rapidly over land, while its track shifted more to the north around a ridge to the east. It emerged into the Luzon Strait between the eponymous island and Taiwan with a much larger eyewall, and failed to re-intensify over open waters. Late on October 15, Zeb passed within of Taiwan's east coast before accelerating to the northeast due to a passing trough. The JMA downgraded the typhoon to tropical storm status on October 16, although the JTWC retained Zeb at typhoon status. Favorable upper-level conditions allowed the storm to briefly re-intensify after passing Taiwan, although this was short-lived,