* WHAT...For the first Small Craft Advisory, north winds 15 to 20 kt with gusts up to 25 kt and seas 7 to 9 feet. For the second Small Craft Advisory, seas 6 to 11 feet expected. * WHERE...Waters from Pt. St. George to Cape Mendocino CA from 10 to 60 nm. * WHEN...For the Small Craft Advisory, until 3 PM PDT this afternoon. For the Small Craft Advisory, from 11 PM Thursday to 5 PM PDT Friday. * IMPACTS...Conditions will be hazardous to small craft. * ADDITIONAL DETAILS...Steep westerly seas will rapidly increase late thursday through Friday morning. Seas may reach hazardous levels of 12 ft in northwest portions of this zone. Inexperienced mariners, especially those operating smaller vessels, should avoid navigating in hazardous conditions.