Margaret River seasonal overview
Best Surf Season (May - September)
Winter in the Southern Ocean unleashes its fury and Margaret River goes full-pumping. From May through September, the average swell hovers around a solid 2.3m to 2.8m, with periods consistently in the 12.9-13.3s range – that's powerful, long-period groundswell that wraps perfectly into the West-South-West facing coastline. The dominant swell directions shift to SW and WSW, the exact sweet spot for this stretch of coast. While onshore westerlies can be a menace, the prevalence of E to NE winds during high-pressure setups offers clean, glassy conditions especially in the mornings. This is prime time for pumping 1.5-2.5m plus waves at iconic spots like The Box and Mainbreak.
Fair Surf Season (April & October)
Shoulder months bring a transition period where the ocean is still very much alive. April and October see average swells between 2.0m and 2.2m with periods around 12.8-12.9s – solid and rippable. Wind ideal percentages climb to 29% in April thanks to more frequent easterly regimes, while October cools off slightly. These months can deliver fun, clean waves without the peak-winter crowds, making them a favorite for those seeking quality over quantity.
Low Surf Season (November - March)
Summer settles in and the Pacific High-pressure system dominates the Indian Ocean, suppressing the storm track. From November through March, average swell heights drop to 1.8-1.9m and periods slip to 11.8-12.5s. While still rideable, the swell tends to be more windswell-infused and less consistent. The wind regime is dominated by afternoon sea breezes – SSE to SW onshores that wreck wave quality. However, early morning offshore easterlies from the land breeze can still create short windows of fun, groveling waves in the 0.5-1.5m range. March stands out as the best of the low season with 21% ideal wind and longer average periods (12.5s), hinting at the approaching winter swell.
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Conditions at Margaret River in September
September: Spring Transition Begins
September signals the beginning of the end of winter dominance. Average swell height remains solid at 2.6m with a period of 13.2s – still powerful. Swell direction is dominated by SW (28.4%) and WSW (15.9%), but the energy is slightly less consistent. Wind ideal percentage stays low at 18%, but the wind patterns start shifting: westerly winds (W 12.1%, WSW 11.9%, WNW 11.0%) remain strong, but there's an increase in SE to SSE winds (SSE 6.6%, SE 5.5%), which are offshore. The morning light easterlies become more reliable. This month can deliver pumping 1.5-2.5m waves with clean conditions in the early hours, and the crowds thin out a bit. Great month for quality over quantity.
Average Spot conditions at Margaret River in September
Swell history for September
Wind history for September
Swell quality
Analyze the groundswell consistency at Margaret River 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 Margaret River for your next trip in September.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Margaret River 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 Margaret River.
