Tropical Storm Carlotta has formed in the Pacific south of Mexico and is expected to become a hurricane.
Carlotta's maximum sustained winds increased Thursday morning to near 45 mph. The U.S. National Hurricane Center in Miami says additional strengthening is forecast and Carlotta is expected to become a hurricane by the time it reaches Mexico's southern coast on Friday.
A hurricane watch is in effect for Mexico's Pacific coast from Barra de Tonala to Punta Maldonado.
The tropical storm is centered about 405 miles south-southeast of Puerto Angel, Mexico, and 600 miles southeast of Acapulco, Mexico. The storm is moving northwest near 10 mph.
Tropical storm-force winds are extending outward up to 45 miles from the storm's center.