* WHAT...For the Dense Fog Advisory, dense fog will reduce visibility to one quarter mile or less. For the Small Craft Advisory, northeast winds to 30 kt and significant waves to 10 ft occasionally to 13 ft expected. * WHERE...Winthrop Harbor to Calumet Harbor IL. * WHEN...For the Dense Fog Advisory, until 9 AM CDT this morning. For the Small Craft Advisory, from 7 AM this morning to 7 PM CDT Tuesday. * IMPACTS...Conditions will be hazardous to small craft. Low visibility will make navigation difficult. Inexperienced mariners, especially those operating smaller vessels, should avoid navigating in hazardous conditions. If you must navigate, proceed with caution. Use proper fog signals. Make sure all running lights are on. Remember to use your radar and compass.