Johanna - surf spot statistics

Best Surf Season (May - September)

The Southern Ocean fires on all cylinders from May through September, delivering Johanna's most consistent and powerful swell. Average wave heights climb to the 2.6-2.9m range with periods hovering around 13 seconds – that's long period, groundswell territory. The dominant SW and WSW energy slams straight into this SSW-facing beach, producing hollow, rippable walls. Winter's strong frontal systems and deep low-pressure cells spinning up near Antarctica are the driving force. Offshore winds from the N, NNE, and NE occur roughly 30-35% of the time, often aligning with post-frontal high-pressure ridges. When it all comes together, you get pumping, firing surf with clean, offshore texture.

Fair Surf Season (April & October)

April and October serve as transitional windows where the swell quality remains high but consistency and wind reliability take a small step back. April still pumps out an average 2.5m swell at 12.7s, with a solid 33% offshore wind score – one of the best wind percentages of the year. October sees the swell start to wind down (2.7m, 12.6s) and the offshore wind window drops to 25%, but the predominant SW/WSW swell still offers plenty of fun, solid waves. These months can dish out epic days when a late-season storm aligns with a northerly breeze.

Low Surf Season (November - March)

The summer months from November through March bring the smallest average surf of the year (2.3-2.4m, 11.7-12.0s), though even these numbers are respectable by many standards. The real issue is the dominance of onshore winds from the S, SW, and WSW – the same directions that bring the swell – which create bumpy, chop-ridden conditions. Ideal offshore wind percentages drop to 22-25%. The swell still rolls in from the SW and WSW, but periods are shorter and the wave heights often sit in the 1-2m fun-size range. It's not a write-off: early mornings or days with a strong inland heat trough can produce brief offshore windows, but overall consistency and quality take a seasonal dip.

June: Peak Winter Power

June is the heart of the southern winter, and Johanna feels it. Average swell height rises to 2.7m, period holds at 12.9s, and the offshore wind percentage remains high at 33%. Swell direction broadens: SW (18%) is still the leader, but WSW now accounts for 17% – nearly equal – meaning more westerly energy wraps in. This increases the exposure to the open ocean and can create bigger, more powerful waves. Wind patterns shift: N and NNW winds dominate (25% combined) and are often moderate to brisk. These are offshore to cross-offshore and can groom waves exceptionally well. However, stronger afternoon sea breezes from the W and SW can spoil an otherwise excellent day. The best windows are early morning before the thermal gradient kicks in. June delivers pumping, charging surf for the brave.