Conditions at Almagreira in December
December: Winter's Big Swell Machine
December delivers the full power of the Portuguese winter. Average swell height is around 9ft (2.7m), average period is 12.8s, and the North Atlantic is a hive of low-pressure systems sending consistent, long-period energy toward Almagreira. The NW and WNW swell sources remain the main event - NW 18.6%, WNW 13.2%, NNW 10.4% - and there is a noticeable increase in WSW/W swell too, keeping the beach active even when the more northwesterly tracks wobble.
The chart's most exciting stat is the wind: ideal offshore conditions hit 31% of the time, the highest of the year. Although ESE winds are common at 11.2%, they are less damaging than the summer NNW gales, and a clean S/SW/WSW flow combined with big NW groundswell can produce truly memorable, heavy days. Water temp has cooled to 15.0°C, air temps average 13.0°C, and rain is plentiful at 2.93 mm/day - a small price for some of the finest waves on the calendar.
Average Spot conditions at Almagreira in December
Swell history for December
Wind history for December
Swell quality
Analyze the groundswell consistency at Almagreira 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 Almagreira for your next trip in December.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Almagreira 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 Almagreira.