Conditions at Matosinhos in September
September: Autumn Transition Begins
September is where the spark returns. Average swell height rises slightly to 3-4ft (1.1m) and the period lengthens to 10.4s as early autumn lows begin to reawaken the North Atlantic. The swell direction remains anchored in the NW/WNW quadrant, totaling more than 80% of the spectrum, but the period is the biggest change: those 8-9s summer windswells start to be replaced by more organized, longer-period groundswell. The wind is ideal 46% of the time, and while the summer nortada still blows, its grip weakens through the month. Water temp remains warm at 16.8°C, air temps average 19.2°C, and rainfall edges up to 1.92 mm/day. When a first proper W or WNW groundswell coincides with a morning E/NE wind, September can serve up the surprise session of the year.
Average Spot conditions at Matosinhos in September
Swell history for September
Wind history for September
Swell quality
Analyze the groundswell consistency at Matosinhos 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 Matosinhos for your next trip in September.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Matosinhos 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 Matosinhos.