Santa Marinella • Statistics for December

December: Peak Season - Short Periods But Maximum Energy

December is the statistical peak of the surf year at Santa Marinella, with the highest average swell height of any month: around 3.3ft (1.0m), supported by an average period of 5.2s. The swell rose still shows plenty of energy from the SW and WSW sectors, at 12.8% and 11.2% respectively, but the favourable SSE direction is close behind at 10.8%, with S at 8.6%, SSW at 7.2% and SE at 6.5%. The heights in these directions are the most promising of the calendar year: SSE has 2.5% at 1-1.5m (3-5ft), 1.3% at 1.5-2m (5-6ft) and 0.4% at 2-2.5m (6-8ft), while S and SSW show comparable distributions. What sets December apart from the rest of winter is the improved wind profile. NNE winds are strong at 12.4%, and NNW adds 7.7%, giving the offshore ideal window about 11% of the time. When a deep Tyrrhenian low lines up with a northerly airstream, Santa Marinella can offer properly pumping short-period waves, often in the 4-6ft (1.2-1.8m) range. Water temperature is 15.9C, air averages 11.1C and precipitation is 2.87 mm/day. Winter has arrived, and the surf does not get any better than this.