Conditions at Backdoor in December
December: Winter Legend Status
December delivers some of the most significant swell episodes of the entire year. The average swell height ties the annual maximum at 2.7m (8.9ft), and the average period is a solid 12.4s. The swell rose is led by NNW at 14.1%, with NNE (7.9%), ENE (7.8%), NE (7.1%), N (4.1%), and NW (4.1%) contributing. For a northwest-facing reef, those NNW and NW pulses are exactly what you want: long-period, heavy, and square to the coast. The 1.5-2.5m (5-8ft) range is full, and there is a meaningful over-2.5m (8ft+) component. Winds are still predominantly from the east (E 29.1%, ENE 24.8%), but ideal offshore wind occurs 24% of the time, and winter cold fronts can bring brief Kona wind episodes from the southwest. When it all lines up, Backdoor is one of the most challenging and spectacular waves on earth. Air temperature is 23.6°C (min 19.0°C, max 27.6°C), precipitation is 2.29 mm/day, and water temperature drops to 24.8°C.
Average Spot conditions at Backdoor in December
Swell history for December
Wind history for December
Swell quality
Analyze the groundswell consistency at Backdoor during December. Based on historical data, there is a % probability of groundswell occurring this month. The chart below provides a detailed breakdown of the average wave height distribution, offering deep insights into the swell quality and surf potential you can expect at Backdoor for your next trip in December.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Backdoor for December. Our analysis shows that favorable offshore or side-shore winds coincide with surfable swell approximately % of the time. The accompanying graph illustrates the average size distribution of waves during these optimal wind windows at Backdoor.