Nadine, Kristy churn in Atlantic, Pacific Tropical Storm Nadine, with maximum sustained winds of 70 mph, was about 800 miles east-northeast of the northern Leeward Islands, moving northwest at 16 mph, the National Hurricane Center in Miami said in its 5 a.m. 13 (UPI) -- Tropical Storm Nadine neared hurricane strength in the Atlantic Ocean as Tropical Storm Kristy churned the surf in the Pacific, U.S. forecasters said Thursday. Nadine, with maximum sustained winds of 70 mph, was about 765 miles northeast of the northern Leeward Islands, moving north-northwest at 15 mph, the National Hurricane Center in Miami said in its 11 p.m. Forecasters said Nadine could strengthen to a hurricane in the next day or two. The storm was expected to shift to the north Friday then turn toward the northeast by Saturday. Tropical storm-force winds extended outward from the center as far as 230 miles. In the Pacific, Tropical Storm Kristy, with 50 mph maximum sustained winds, was about 65 miles north of the Socorro Islands and about 235 miles south-southwest of the southern tip of Baja California, Mexico, the National Hurricane Center said. It was moving west-northwest at 10 mph. Forecasters said the coast of southwestern Mexico and the southern Baja Peninsula could expect rough surf. Kristy was expected to move toward the west-northwest for the next 48 hours and could strengthen some during that time, forecasters said. The center should pass south of the southern tip of Baja California, in the next 24 hours. Tropical storm-force winds extended outward from center as far as 80 miles. Swells generated by Kristy will affect portions of the coast of southwestern Mexico and southern Baja California, for the next couple of days, the center said. The swells likely will cause life-threatening surf and rip currents.