Tropical Storm Sandra has formed in the eastern Pacific well south of Mexico and is expected to later strengthen to a hurricane.
The storm's maximum sustained winds Tuesday morning are near 45 mph (75 kph). The U.S. National Hurricane Center says Sandra is expected to become a Cat. 1 hurricane (74-95 mph winds) on Wednesday.
The National Hurricane Center reports that as of 3 a.m. Central time Tuesday:
During the next 3-4 days, Sandra is forecast to gradually slow down as it moves around the western periphery of a deep-layer subtropical ridge that extends from the southwestern Gulf of Mexico westward across central Mexico. On days 4 and 5, the cyclone is expected to turn northeastward and accelerate ahead of a strong mid-latitude trough that will be moving eastward toward the western coasts of the United States and Baja California....
By day 4, strong southwesterly shear in excess of 30 kt is expected to induce rapid weakening as Sandra recurves into the mid-latitude westerlies.
The storm is centered about 570 miles (915 kilometers) south of Manzanillo, Mexico, and is moving west near 13 mph (20 kph)
Sandra is the 18th named storm of the 2015 eastern North Pacific hurricane season.