(Portland, OR)  --  The National Weather Service is warning beach-goers about an increased chance of sneaker waves along the Oregon coast this week.  The agency has issued a Beach Hazards Statement for the central and north Oregon Coast tomorrow through early Thursday.  Sneaker waves are waves that run farther up onto the beach than other waves.  The powerful waves have been known to pick up large logs and are strong enough to knock a person over and drag them into the ocean.