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Thunders • Statistics for December

Conditions at Thunders in December

December: Festive Swell Under a Fickle Monsoon Ceiling

December rounds out the year with the return of full northwest monsoon conditions. Average swell height is 1.3m (4.3ft) and the average period is 12.3s - solid, rideable groundswell, but less of the long-period juice than the dry season. Swell direction remains favorable: SSW leads at 47.4%, SW contributes 27.9%, WSW 11.6%, and S 10.6%. The largest slice of waves, 67.8%, falls in the 3-5ft (1-1.5m) range, and another 18.6% goes 5-6.5ft (1.5-2m). So the break rarely goes flat.

The culprit is the wind. NW/WNW/NNW flow totals a huge 58.2% of observations, and W adds another 8.6%, leaving the beach exposed to a lot of chop and lump. The ideal surfing wind percentage is the lowest of the year, just 26%. Rain reaches 9.59mm/day, though air is warm at 27.2°C and water sits at 28.9°C. December is a month for the patient surfer: wait for a passing squall line to clear the coast and an east/northeast wind to fill in behind it, and those SSW lines can still offer fun, racetrack waves at Thunders.

Average Spot conditions at Thunders in December

Swell history for December

0 - 2
2 - 3
3 - 5
5 - 6
6 - 8
> 8 ft

Wind history for December

0 - 6.2
6.3 - 12.4
12.4 - 18.6
18.6 - 24.9
24.9 - 31.1
> 31.1 mph

Swell quality

Analyze the groundswell consistency at Thunders 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 Thunders for your next trip in December.

Ground swell

Ground swell by size

Wind conditions

Evaluate the wind and swell alignment at Thunders 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 Thunders.

Swell with good wind

Swell with good wind by size

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