Strong northerly winds this weekend are expected to send a large swell to the north-northwest of the Hawaiian Islands that could inundate coastal roads and erode beaches, forecasters said.

“Due to the combination of the giant surf, strong northerly winds, and near peak monthly high tides, overwash of low-lying coastal areas and roadways is likely Sunday through Monday, with the most vulnerable time frame around the high tide cycle Sunday night,” said a special weather statement from the National Weather Service in Honolulu. “Also, significant beach erosion can be expected and strong harbor surges may cause damage to boats and infrastructure along north and west facing coastlines and harbors.”

Winds are approaching within 500 nautical miles (about 575 statute miles) of the state, the weather service reports.

“Surf is expected to rapidly build early Sunday morning, peak Sunday evening into Sunday night at giant levels and steadily decrease Monday into Tuesday,” forecasters said.

Overwash is likely for low-lying coastal areas and roadways from Sunday through Monday.

Forecasters said significant beach erosion can be expected, and strong harbor surges could cause damage to boats and infrastructure along north- and west-facing coastlines and harbors.