...HIGH SURF ADVISORY FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU MOLOKAI AND NORTH FACING SHORES OF MAUI... .Surf from a large, north-northwest swell will maintain at near- warning level this morning and will begin to decrease this afternoon. Surf is expected to start falling below advisory levels by tonight. * WHAT...For north-facing shores, surf 18 to 24 feet this morning, then diminishing through the day. For west-facing shores, surf 14 to 18 feet this morning, then diminishing through the day. * WHERE...North and west facing shores of Niihau, Kauai, Oahu, Molokai and north facing shores of Maui. * WHEN...Until 6 PM HST this evening. * IMPACTS...Moderate. Strong breaking waves and strong currents will make swimming dangerous.