Sunday swell spares sand as forecasters eye big Wednesday waves

NORTH SHORE, OAHU (HawaiiNewsNow) - Waves along Oahu's North Shore were big again on Sunday, but not big enough to threaten homes near Rocky Point. But homeowners are worried about a swell that's expected to roll in on Wednesday.

Sunday's swell wasn't quite as big as advertised, which was good news for the owners of homes on Ke Nui Drive, where waves have eaten away at the sand. The waves lapped at the homes from time to time, but didn't take away any more sand.

The swell was the second of a series, and followed a large swell that rolled in Thursday and Friday. But there's a third swell headed our way from a low pressure system off Japan that forecasters are watching very closely.

According to the latest computer forecast models, the low will intensify rapidly and could produce an open-ocean swell of 20 feet. That translates to waves that could be up to double that height by the time it reaches the state.

"The one that's coming in for Wednesday has the potential to be larger, actually much larger, something that we don't see every year, something that you might see only on the order or every five to ten years," said Derek Wroe, a lead forecaster with the National Weather Service.

This year's big surf season has been active compared to some recent years, with the waves eating away at the shoreline near several North Shore homes. Marine biologist and environmentalist Terry Lilley contends the erosion will happen more often.

"We're losing about a foot of sand every year, permanently off the North Shore," said Lilley, "
And as the sea levels are rising now every year, that pushes salt water back underneath the homes, and it's only going to get worse every year, not better."

The forecast for Wednesday's swell has another cause for concern. Sunday's swell rose and peaked quickly, lasting perhaps just 12 hours. Wednesday's big waves could last 24 hours -- or longer.

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