Tropical Storm Fico turned to the northwest after reaching tropical storm status, and entered an area of increasingly warm water temperatures. It quickly strengthened, and 18 hours after becoming a tropical storm Fico strengthened into a hurricane. As the hurricane turned to the west-northwest, a well-defined eye developed in the center of the hurricane, and Fico continued to quickly intensify. Fico attained Category 4 strength about 24 hours after it first became a hurricane, and on July 12 it reached peak winds of 140 mph (220 km/h) while located 640 miles (1,030 km) southwest of Cabo San Lucas. Throughout its duration, the eye of the hurricane was around in diameter.