Motunau Beach Island - surf spot statistics

Best Surf Season (May - August)

Winter roars to life along the southeast coast of New Zealand, transforming Motunau Beach Island into a consistent, high-quality surf destination. During these months, the Southern Ocean cranks out powerful storms that send long-period groundswells marching northward. The average wave period climbs above 10.5s, and the percentage of offshore wind from the north quadrant jumps to over 54 percent. This means you can score clean, lined-up waves with pumping (1.5-2.5m) sets wrapping into the bay. Swell directions from the SSE, S, and SSW dominate, making the most of the island's south-east exposure. When a high-pressure system parks itself to the north, light northerlies groom the surface to perfection – classic winter perfection.

Fair Surf Season (April & September)

The shoulder months offer a blend of fading winter energy and the early stirrings of spring. April still sees a solid average period of 10.8s and a 48 percent chance of offshore winds, while September maintains 10.4s and 47 percent offshore. Swell heights average around 1.2m, with plenty of fun, good, solid (1-1.5m) waves from the south and southeast. However, the trade-off is increased variability: you might get a few days of clean, long-period swell followed by a stint of onshore easterlies. If you time it right, these months deliver excellent sessions with fewer crowds.

Low Surf Season (October - March)

Summer and early autumn are the most challenging times at Motunau Beach Island. The average wave period drops to 9.2-10.1s, and swell heights hover around 1.1-1.2m. The dominant swell shifts to the ENE, E, and ESE – not the optimal angles for this spot – often accompanied by onshore winds from the same directions. Offshore wind percentages dip to 33-41 percent, meaning you'll spend more time battling chop than carving clean lines. Even when the odd southerly swell slips through, the short periods and smaller heights keep waves in the small, fun-sized, groveling (0.5-1m) category. That said, if you're willing to work for it, the odd north-westerly change can bring a few hours of reeling peaks before the next sea breeze kicks in.

September: Spring Transition – Fewer Windows, Still Good

September marks the beginning of spring and a gradual decline in consistency. Offshore wind drops to 47%, and average period eases to 10.4s. Swell height averages 1.2m, with a directional split between E (16.4%), ESE (14.7%), SSE (12.5%), and S (11.7%). The wind pattern is still favourable – NW (17.1%), WNW (10.0%), NNW (11.1%) – but the frequency of onshore easterlies increases. You'll need to pick your sessions carefully. When a late-winter low brushes the south, it sends a pulse of long-period groundswell that combines with offshore north-westerlies for clean, powerful waves. Most days, though, are smaller – small, fun-sized (0.5-1m) to fun, good (1-1.5m). The potential for a great day exists, but the consistency of the winter months has faded.