Ericeira seasonal overview
Best Surf Season (October - March)
The North Atlantic roars to life from October through March, delivering the most consistent and powerful swell to Ericeira's west-facing coastline. During these months, average wave heights hover between 2.0m and 2.6m, with periods often exceeding 12 seconds — classic long-period groundswell generated by frequent extratropical storms traversing the North Atlantic. The NAO index often shifts negative, steering stronger, more organized low-pressure systems toward the Iberian Peninsula. Offshore wind conditions improve as well, with ideal wind percentages climbing to 24-28%, typically from the north and northwest (NO, ONO). This creates lined-up, hollow waves at Ericeira's world-class reef and beach breaks. This is the time to chase big, powerful surf.
Fair Surf Season (April & September)
April and September serve as transitional windows. Swell heights drop slightly to 1.6-2.0m and periods shorten to 10.5-11.1 seconds as the storm track begins to shift. However, the combination of moderate long-period and shorter-period windswell still provides plenty of rideable days. The wind becomes more variable — ideal percentages fall to 17-20% — with more spring-like westerly and northerly flows. Expect fun, rippable waves on good days, especially when a passing low taps into the northern Atlantic swell window. These months reward flexible scheduling and a keen eye on the charts.
Low Surf Season (May - August)
From May through August, Ericeira experiences its quietest surf. Average swell heights drop to 1.4-1.7m and periods shorten to 8.5-9.9 seconds, dominated by local windswell from the north-northwest (NNW, NW). The wind regime shifts dramatically: the Portuguese trade wind pattern strengthens, blowing 20-40kph from the north up to 44% of the time, creating choppy onshore conditions for the west-facing breaks. Ideal offshore wind percentages fall to a mere 7-13%, making clean waves a rare commodity. While smaller days can offer fun, groveling sessions for those on the right equipment, the real heavy moments are few and far between. Summer surf here is best tackled with a longboard or a forgiving fish, and a good dose of patience.
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Conditions at Ericeira in September
September: The Fall Transition Kicks In
September marks a decisive shift toward more energetic surf. Swell height climbs to 1.6m, and period jumps to 10.5s — the beginning of the autumn groundswell influx. The dominant swell directions start to broaden: NW leads at 36.0%, followed by NNW at 34.4% and WNW at 15.4%. Importantly, you see more westerly component (W at 4.4%, WSW at 1.9%) and even some SW (0.8%), indicating the storm track is reactivating. Wave heights spread out: 1-1.5m (36.0%), 1.5-2m (25.5%), and even some 2-2.5m (11.0%) and over 2.5m (0.3%). Ideal wind conditions improve to 20%, as the north wind weakens slightly (N down to 34.3%, with heavy speeds 20-40kph at 24.0%). The wind also becomes more variable, with increased easterly components (ENE, E, ESE totalling 4.1%) that can provide offshore conditions. September is a prime month for catching the first solid swells of the season with generally lighter winds. Look for storms developing in the North Atlantic — they deliver long-period swell that wraps beautifully into Ericeira. This is a hidden gem month.
Average Spot conditions at Ericeira in September
Swell history for September
Wind history for September
Swell quality
Analyze the groundswell consistency at Ericeira 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 Ericeira for your next trip in September.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Ericeira 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 Ericeira.
