Portrush - surf spot statistics

Best Surf Season (October - March)

The North Atlantic roars to life during these months, with average swell heights consistently over 1.8m and long periods of 10-12s. Powerful extratropical storms track across the Atlantic, sending consistent W to NW swell into Portrush's northwest-facing beaches. However, the trade-off is the prevalence of onshore winds from the west and northwest, which can ruin wave quality. Still, when a strong high-pressure system settles over the British Isles or a low tracks just right, the region can see offshore winds from the south and southwest combining with pumping, clean swell. That is when Portrush truly shines.

Fair Surf Season (April & September)

These transitional months see a drop in average swell size (1.4-1.5m) and period (9.3-9.7s), but a noticeable increase in the frequency of favorable offshore winds (16-18% ideal). The swell energy is more moderate but often punchy, and the wind tends to back off, offering more clean sessions. Spring and early autumn can deliver fun, rippable waves with less crowd pressure.

Low Surf Season (May - August)

Summer brings the smallest swell of the year, averaging just 1.0-1.2m with periods around 8-9s. While the percentage of ideal offshore wind climbs to 18%, the swell source is weak – often just local windswell or very long-period groundswell from distant lows. Most days are small but can be fun on a log or groveler. The predominant wind shifts more to the north and northeast, which can be cross-shore or even offshore, but the lack of size keeps the energy low. Consistent, clean small waves are the norm, not the exception.

July: The Dog Days of Swell

July is the absolute trough of swell size, averaging 1.0m with the year's shortest period of 8.1s. The swell direction is heavily weighted to W (28.6%) and WNW (32.6%), but almost all of it is under 1m. Despite the small swell, the wind regime is very consistent: 18% ideal. The wind rose shows a broad distribution with many light winds from the south and southeast, offering frequent offshore mornings often followed by sea breezes. The swell is almost entirely windswell or very weak groundswell. Expect tiny, fun waves that need a foam board or a log. The North Atlantic is asleep, but the beaches are alive with clean, rideable ripples.