MIAMI (AP) -- Forecasters say Hurricane Hilary has strengthened into a small, but powerful Category 4 storm in the Pacific.

Hilary's maximum sustained winds were near 135 mph (217 kph) Thursday. The hurricane is not forecast to make landfall, though officials say it is expected to rake Mexico's coast with wind, rain and heavy surf.

The U.S. National Hurricane Center says 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 85 miles (137 kilometers) southwest of Acapulco, Mexico, and is moving west-northwest.

In the Atlantic, Tropical Storm Ophelia is weakening.

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