Conditions at Aterro in December
December: Winter Swell Peak and the Holiday Score
December ties the seasonal peak in swell quality. Average wave heights run 8ft (2.5m) with a period of 12.5 seconds, and Aterro's west-northwest exposure lines up perfectly with the Atlantic's late-year energy. WNW (18.5%), NW (19.8%), W (7.8%) and WSW (3.6%) all supply powerful groundswell, while even a touch of SW (2.2%) and S (0.4%) adds directional variety.
It also has the highest ideal wind percentage of any month at 48%. Continental E (13.3%) and ESE (9.2%) winds, plus SSE and S (8.3%/8.8%), deliver plenty of glassy and offshore mornings. NNW (9.0%) is at an annual low. Air temps are cold at 11.3°C, water drops to 13.9°C, and precipitation is 4.37 mm/day. December is a serious month for big, clean surf if the wind clock aligns.
Average Spot conditions at Aterro in December
Swell history for December
Wind history for December
Swell quality
Analyze the groundswell consistency at Aterro 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 Aterro for your next trip in December.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Aterro 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 Aterro.