Tropical storm Hilary forms in the Pacific south of Mexico

Tropical storm Hilary has formed in the Pacific south of Mexico and is expected to get stronger. The storm could become a major hurricane by Friday night.

This NASA image from NOAA's GOES-13 satellite was captured on Wednesday and shows tropical storm Ophelia (r.) as a large and still disorganized area of clouds. Tropical storm Hilary is forming in the Pacific as tropical storm Ophelia's winds are near 65 mph but expected to weaken in the Atlantic.

NOAA GOES Project/NASA/Reuters

September 22, 2011

Hurricane Hilary has formed in the Pacific south of Mexico and is expected to get stronger.

Hilary's maximum sustained winds are near 75 mph (120 kph) Thursday. The U.S. National Hurricane Center says additional strengthening is expected and the storm could become a major hurricane by Friday night.

A tropical storm warning is in effect for Mexico's coast from Lagunas de Chacahua to Punta San Telmo. A tropical storm watch is in effect for west of Punta San Telmo to Manzanillo.

Hilary is centered about 140 miles (225 kilometers) south-southeast of Acapulco, Mexico, and is moving west-northwest near 10 mph (17 kph).

In the Atlantic, Tropical Storm Ophelia's winds are near 65 mph (100 kph) but it's expected to begin weakening.