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.

March: Autumn Build-Up

As autumn begins, Johanna enters a transition stage. Average swell height inches up to 2.4m and period stretches to 12.4s, indicating stronger, longer-period energy. The SW swell machine is still churning (35% from SW), but now we see a rise in SSW swell (13%) and a slight drop in WSW (7%). Ideal offshore wind hits 28%, the best so far in the calendar year. The wind rose shows a notable increase in NW and NNW flow – both are cross-offshore directions that can clean up the waves. The first deep Southern Ocean lows start to form, sending pulses of powerful WSW groundswell. March often delivers a few world-class sessions before the autumn equinox.