MEXICO CITY - Hurricane Amanda rapidly gained force far off of Mexico's Pacific coast Sunday, growing into the strongest May hurricane on modern record for the Eastern Pacific, with sustained winds of about 150 mph.

The U.S. National Hurricane Center in Miami said the main body of the category-4 hurricane posed little threat to land, however. It was centered about 740 miles south of the southern tip of Baja California at midafternoon, and forecasters expected it to weaken while staying well out to sea, at least through Friday. Earlier Sunday, its maximum winds had hit 155 mph.

Even so, Mexico's National Meterological Service said rains associated with Amanda were likely to drench much of western and central Mexico.

The previous May record for the region was held by Hurricane Adolph in 2001, which had sustained winds of up to 145 mph. Earlier storms may have been stronger, but reliable records didn't become possible until satellites went into use in the mid-1960s.

The Eastern Pacific hurricane season officially started May 15. The Atlantic season starts June 1.