Screenshot of a tropical depression in the eastern Pacific ocean southwest of Mexico on Sunday, June 23, 2013 from the National Hurricane Center website.

Screenshot of a tropical depression in the eastern Pacific ocean southwest of Mexico on Sunday, June 23, 2013 from the National Hurricane Center website. (© NOAA/ National Weather Service)

MIAMI (AP) — Forecasters say a tropical depression has formed in the Eastern Pacific and is stationary about 500 miles off the coast of Manzanillo, Mexico.

The National Hurricane Center in Miami says the depression has maximum sustained winds of 35 mph (55 mph). There are no coastal watches or warnings in effect as of Sunday morning.

The center says the storm system has been moving erratically but is expected to move west-northwest over the next few days with increasing speed. Forecasters expect the depression to remain well south of Mexico's Pacific coast. They also note that it could strengthen over the next day.

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