On October 18, Wilma intensified into a hurricane, and subsequently underwent explosive deepening over the open waters of the Caribbean Sea. In a 30–hour period through October 19, Wilma's barometric pressure dropped from 982 mbar (29.00 inHg) to 882 mbar (26.05 inHg); this made Wilma the most intense Atlantic hurricane on record, based on pressure. During the same intensification period, the winds increased to a peak intensity of 185 mph (295 km/h), making Wilma a Category 5 on the Saffir-Simpson scale. An eyewall replacement cycle caused Wilma to weaken below Category 5 status on October 20, as it drifted northwestward toward Mexico's Yucatán Peninsula. Late on October 21, Wilma made landfall on the island of Cozumel, Quintana Roo, with sustained winds of 150 mph (240 km/h). About six hours later, Wilma made a second landfall on the Mexican mainland near Puerto Morelos.