Above: Forty-hour forecast (01/02/11 at 6:00 p.m.) for the Waimea Bay buoy is 9.8 feet at 16.1 seconds (309°).
Below: Observed conditions at the Waimea Bay buoy at 5:42 p.m. on January 2nd, 2011 were 9.2 feet at 18.2 seconds.
Actual peak was pretty in tune with the 40-hour forecast. Need some visual proof?
By the way, the Waimea buoy is on the rise again.