* WHAT...Large waves and hazardous surf conditions. Breakers up to 25 feet. * WHERE...North and Central Coast of Oregon, and South Washington Coast. * WHEN...From 10 AM this morning to 4 PM PST Thursday. * IMPACTS...Destructive waves may wash over beaches, jetties, and other structures unexpectedly. People can be swept off rocks and jetties and drown while observing high surf. Minor beach erosion may damage coastal properties and buildings. Higher than normal water run-up is expected on beaches and low- lying shoreline. * ADDITIONAL DETAILS...The largest waves are expected to occur between 4 PM Wednesday and 7 AM Thursday.