Kohala Lighthouse • Statistics for December

December: Peak Season at the Lighthouse

December has arrived, and Kohala Lighthouse finally looks like a proper North Shore wave. Average swell height matches the seasonal max at 1.9m (6.2ft), the average period is a robust 12.0s, and the north quadrant is heavily represented: N comes in at 2.3%, NNE at 7.3%, NE at 17.2%, NW at 1.8% and NNW at 5.8%, combining for roughly 34% of all swell energy - plus another big chunk of ENE/E that is often angled enough to add push. This is the month when long-period NW-NE groundswells march through the Hawaiian chain with regularity, and the lighthouse has the exposure to feel every bit of it. Trades still dominate the wind rose at 75.2% from ENE/E, but ideal wind reaches 13%, one of the best of the year. With precipitation at 3.40 mm/day, frontal passages are common enough to deliver the S/SW offshore flows that groom the reef. Water temperature is still a generous 25.1°C and air temps sit at 20.1°C. If you have been waiting all year for the magic combination of size, period and wind, December is the month to be at Kohala Lighthouse.