CNN:- Sam started Thursday as a tropical storm, with winds of 35 mph, and ended the day at 70 mph -- a rapid intensification that occurs when a tropical cyclone strengthens by at least 35 mph in 24 hours. By Friday morning Sam had strengthened into a hurricane, and it may undergo a second rapid intensification cycle this weekend, as it's forecast to become a major hurricane -- category 3 or higher -- by Saturday afternoon. Sam is the seventh hurricane of the 2021 Atlantic season, with winds of 85 mph and even higher gusts, according to a Friday update from