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Crab Island • Statistics for April

Conditions at Crab Island in April

April: The Clean Window

April is the month when Crab Island starts to clean up its act. The average swell height drops to 4-5ft (1.2-1.5m) and the period relaxes to 10.8 seconds, but the quality goes up noticeably. Swell direction remains classic winter-to-spring: W leads at 30.1%, WNW is a major 24.4%, WSW contributes 16.5%, and NW 7.3%. In total, around 78% of all swell energy arrives from the preferred western window, mostly in the 0.5-2m (2-6ft) range, with some 2-2.5m (6-8ft) sets still possible.

The real headline is wind. April registers the highest ideal-wind percentage of the year at 21%, with a combined 21.5% of observations from the offshore ENE, E, ESE, and SE directions. This is the first month where you can genuinely expect multiple clean, lined-up days. The average air temperature climbs to 8.9°C, water temperature reaches 9.9°C, and precipitation dips to 2.76mm/day. It is still winter-suit territory, but the improved winds and moderate swell make April the pick of the spring.

Average Spot conditions at Crab Island in April

Swell history for April

0 - 2
2 - 3
3 - 5
5 - 6
6 - 8
> 8 ft

Wind history for April

0 - 6.2
6.3 - 12.4
12.4 - 18.6
18.6 - 24.9
24.9 - 31.1
> 31.1 mph

Swell quality

Analyze the groundswell consistency at Crab Island during April. 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 Crab Island for your next trip in April.

Ground swell

Ground swell by size

Wind conditions

Evaluate the wind and swell alignment at Crab Island for April. 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 Crab Island.

Swell with good wind

Swell with good wind by size

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