...HIGH SURF WARNING FOR NORTH AND WEST FACING SHORES OF NIIHAU KAUAI OAHU MOLOKAI AND BIG ISLAND AND FOR NORTH FACING SHORES OF MAUI...

.An extremely large, long-period northwest swell will peak overnight and early Sunday, producing surf well above the warning levels along most north and west facing shores. Surf will likely decline below warning levels on Monday but remain elevated above advisory levels into Tuesday.

...HIGH SURF WARNING NOW IN EFFECT UNTIL 6 AM HST MONDAY...

* SURF...Along north and west facing shores of Niihau and Kauai, and north facing shores of Oahu, Molokai, and Maui, surf will be 35 to 50 feet through tonight, then slowly decline to 30 to 40 feet on Sunday. Along west facing shores of Oahu and Molokai, surf will be 25 to 35 feet through tonight, then slowly decline to 18 to 25 feet on Sunday. Along west facing shores of the Big Island, surf will rapidly build to 12 to 16 feet tonight and hold through Sunday afternoon.

* TIMING...Surf will peak overnight and early Sunday, and remain well above warning levels through Sunday night.

* IMPACTS...Extreme...Expect ocean water surging and sweeping over beaches, coastal benches, lava flows, and roadways, creating the potential for significant damage to coastal properties and infrastructure, including roadways. Coastal evacuations and road closures are possible. Large breaking waves may affect harbor entrances and channels with significant damage possible to docks, piers, ramps, and boats.

Large breaking surf, significant shorebreak, and dangerous currents make entering the water very hazardous. Anyone entering the water could face significant injury or death. Surf events of this caliber also have the ability to cause coastal overwash and significant impacts to shorelines, especially those already susceptible to erosion. Greatest impacts will coincide with the high tide occurring early Sunday morning.