The National Weather Service today said the next swell should begin rising along north-facing shores across the state sometime late tomorrow night and peak by Saturday morning.

But by Monday night, the third large swell in less than a week will slam shorelines.

Both new swells should produce wave faces in the 30-foot range, said Pete Donaldson, forecaster for the weather service.

"This is the time of year when we just have surf constantly," Donaldson said.

Yesterday's forecast predicted 50-foot faces on north-facing shores and experts said waves that huge probably rolled through occasionally.

"They were big, that's for sure," Donaldson said.

The swell was on the wane all day today, with wave faces this afternoon expected to be 16- to 20-feet.

High-surf warnings were canceled this morning across the state and replaced with several new advisories: a high-surf advisory for north- and west-facing shores on Kaua'i, O'ahu and Moloka'i through tonight; a high-surf advisory for north-facing shores on Maui through tonight; and a high-surf advisory for north-facing shores on the Big Island through today.

So how big was Wednesday?

"We're not too concerned about how big the waves were," Donaldson said. "We are looking to the future so we can warn people. Unfortunately, the estimates you get of wave heights tend to be colored by other things than objectivity."