The first hurricane of the eastern Pacific season formed Saturday and forecasters said it might grow a bit stronger while advancing northwestward off the Mexican coast, potentially causing heavy rainfall on shore.

       The U.S. National Hurricane Center said Hurricane Enrique’s maximum sustained winds strengthened in its first hours but were holding near 85 mph (140 kph) Saturday evening. Earlier forecasts said Enrique could reach Category 2 strength by Sunday, but the center said the latest conditions pointed to only some slight further gain in power.

       The storm’s core was predicted to stay at sea while moving parallel to the coast over the next several days, before beginning to weaken after reaching cooler waters in a few days.

       Enrique was centered about 225 miles (365 kilometers) south of Cabo Corrientes - the bulge on the coast south of Puerto Vallarta - and it was headed to the west-northwest at 6 mph (9 kph).

       The Hurricane Center said Enrique could bring 6 to 12 inches (15 to 30 centimeters) of rain, with isolated maximums of 18 inches (45 centimeters) to coastal parts of Colima, Michoacan and Jalisco states.

       A tropical storm warning was in effect from Zihuatanejo to Cabo Corrientes.

       Mexico’s Defense Department said it was sending troops to aid civilians in advance of the storm.

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