MIAMI—Tropical Storm Elsa has formed over the tropical Atlantic on Thursday morning and is expected to cause heavy rains that may lead to isolated flash flooding and mudslides in the Caribbean. Elsa is the earliest fifth named storm on record, beating out last year’s Eduardo which formed on July 6, according to Colorado State University hurricane researcher Phil Klotzbach. Elsa had maximum sustained winds of 40 mph with higher gusts and was 865 miles east-southeast of the Windward Islands, according to the National Hurricane Center. Tropical-storm-force winds extend outward up to 105 miles from the center. It was moving west at 25 mph. An even faster motion to the west-northwest is expected over the next 24 to 36 hours. The storm is expected to pass near or over portions of the Windward Islands or the southern Leeward Islands on Friday, move into the eastern Caribbean Sea late Friday and Friday …