Tropical Storm Dolly was speeding Sunday toward Mexico's Yucatan Peninsula and the resort of Cancun, packing sustained winds of 45 mph (72 kph), AP reported. Dolly formed Sunday in the western Caribbean, and the U.S. National Hurricane Center issued a tropical storm warning for the Yucatan peninsula from the border with Belize to Campeche. At midday, the center of the storm was about 270 miles (434 kilometers) east of Chetumal. It was moving northeast at 17 mph (27 kph), on course to cross the Yucatan on Sunday night and move over the Gulf of Mexico on Monday morning.