 After maintaining Category 5 status for about 12 hours, Ivan began a steady weakening trend due to another eyewall replacement cycle until reaching winds of 140 mph (225 km / h) on September 10. Early next day, the hurricane reorganized as it reached winds just shy of Category 5 status. However, weakening occurred again due to an eyewall replacement cycle, and at 0330 UTC on September 11 Ivan passed 23 miles (37 km) south of Portland Point, Jamaica, its closest approach, with winds of 150 mph (240 km / h). The hurricane was previously forecast to make landfall on the island, though the weakening and a turn to the west kept the strongest winds offshore; however, sustained winds of Category 4 status were reported. While passing to the south of the island, the hurricane dropped heavy rainfall, with several stations reporting over 2 feet (60 cm) of precipitation. Ivan's last-minute turn to the west was due to a mid-level high pressure system over the eastern Gulf of Mexico. A slight weakening trend continued after passing the island, due to its northern outflow being disrupted by an upper-level low over the Bahamas. As it tracked further away from Jamaica, Ivan again rapidly intensified to Category 5 status, and early on September 12 it reached its peak intensity of 165 mph (265 km / h) with a pressure of 910 mbar (26.87 inHg).
