Surf forecastStatisticsHistorical report

Caldera seasonal overview

Best Surf Season (October - March)

The North Pacific winter brings a subtle uptick in southern hemi groundswell pulses to this exposed West-South-West-facing beach. While wave heights remain stubbornly small, averaging just 0.3m, the extended swell periods (10-14s) hint at a more organized, albeit diminutive, energy. Despite the trade winds blowing from the northeast nearly year-round, the months from October through March see a slightly higher chance of lighter wind days and the faint possibility of a waist-high, glassy wave. It’s a season of micro-sessions where the long-period groundswell can sometimes offer shoulder-high rides on a big day, but expect to be on a groveler more often than not.

Fair Surf Season (April - September)

The core of the wet season sees a further contraction of the swell window. Dominant SSW swell angles (over 70%) continue to feed the coast, but the average height barely registers above 0.3m. The Intertropical Convergence Zone sits overhead, pumping moisture and often strengthening the onshore trade winds from the NNE and NE. This combination results in mostly choppy, messy conditions with very little rideable wave face. Occasional breaks in the wind may coincide with a long-period pulse, but these are rare. The surf is consistently small and wind-affected, making this a genuine low season for quality waves.

Low Surf Season (Year-Round Reality)

Objectively, Caldera is a flat-wave environment for the vast majority of the year. The average swell height hovers around 0.2-0.3m every month, with over 99% of all waves falling in the 0-0.5m range. The wind is never ideal (0% offshore from the optimal NNO-NO-ONO-O directions), and the prevailing northeast trade winds blow directly onshore across the West-South-West-facing beach. While the swell period is often impressive (10-15s), indicating distant storm origin, the lack of any significant height means surfable waves are exceedingly rare. This coast is best suited for days with a rare, powerful southern hemi groundswell that pushes into the 1-1.5m range – but those events are almost non-existent in the climatological record. Patience is a virtue here.

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Conditions at Caldera in September

September: Transition Month with No Change

September begins the transition toward the dry season, but the surf remains stuck in a rut. Average height 0.3m, period 14.2s. Swell is 75% from the SSW, 12% from the SW. All waves under 0.5m. Winds start to show a slight increase in NE and NNE flows (6% each), but S and SSE still dominate (15% and 13%). Ideal wind: 0%. The period is still excellent, but the height is missing. The Intertropical Convergence Zone begins to shift, which may alter wind patterns in the coming months, but for now, the surf is tiny and wind-affected.

Average Spot conditions at Caldera in September

Swell history for September

0 - 0.5
0.5 - 1
1 - 1.5
1.5 - 2.0
2.0 - 2.5
> 2.5 m

Wind history for September

0 - 10
10 - 20
20 - 30
30 - 40
40 - 50
> 50 km/h

Swell quality

Analyze the groundswell consistency at Caldera during September. 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 Caldera for your next trip in September.

Ground swell

Ground swell by size

Wind conditions

Evaluate the wind and swell alignment at Caldera for September. 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 Caldera.

Swell with good wind

Swell with good wind by size