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Conditions at Cardiff Reef in May
May: Summer South Swell Arrives, Onshore Winds Take Over
May is a transition month in Southern California, and at Cardiff Reef it marks the beginning of the summer pattern. The swell mix shifts toward SSW (7.8%), SW (30.3%) and WSW (39.5%), with W (22.1%) still present. The average height holds at around 3-4ft (1.1m) and the average period is an impressive 13.5s, meaning the ocean is full of long-period energy. Most days see 2-3ft (0.6-0.9m) surf, with plenty of 3-5ft (1-1.5m) sets from SW/WSW when the South Pacific wakes up.
The catch is wind. Ideal surf wind plummets to 4 percent. W (25.9%), WSW (25.0%), SW (15.6%) and WNW (9.7%) combine to create persistent onshore/cross-shore conditions. With the west-southwest exposure, this is exactly the wind sector that ruins wave shape. The few good windows are at dawn, before the sea breeze kicks in. With only 0.26 mm/day of rain, May is dry and mild as water temperatures begin climbing to 15.9°C.
Average Spot conditions at Cardiff Reef in May
Swell history for May
Wind history for May
Swell quality
Analyze the groundswell consistency at Cardiff Reef during May. 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 Cardiff Reef for your next trip in May.
Ground swell
Ground swell by size
Wind conditions
Evaluate the wind and swell alignment at Cardiff Reef for May. 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 Cardiff Reef.