Swell direction
SSW to SSE (160°–210°)
South Shore · Oahu
Summer south swells, the lineup that raised Hawaiian surfing.
Get South Shore Oahu live dataFreeBuoy CDIP 233 · Pearl Harbor, Oahu
When the North Shore goes flat in May, the South Shore wakes up. CDIP 233 sits off Pearl Harbor and is the buoy every Honolulu surfer checks before work — it's the data feed for Ala Moana Bowls, Kewalos, Threes, Queens, Diamond Head, and every other south-facing reef from Waikiki to Hawaii Kai. Smaller swells, longer rides, warmer water than the North Shore.
What you want to see on the buoy before you paddle out.
Swell direction
SSW to SSE (160°–210°)
Swell period
14–22 seconds (long-period south swells)
When it breaks
South shore is on at 1.5–2 ft @ 14 s. Solid above 3 ft.
Wind
Trades (E/ENE) are offshore on south shore reefs — best in the world.
South swells travel from the Southern Hemisphere and arrive long-period and clean. A 2 ft buoy reading at 18 s lights up Ala Moana Bowls — don't let the small numbers fool you.
South swells originate near New Zealand and travel 5,000+ miles to reach Hawaii. By the time they arrive, only the long-period energy survives. A 2 ft @ 18 s reading on 233 will produce overhead waves at Bowls because the energy stacks up as it hits the shallow reef. North swells don't behave this way — but South swells almost always do.
Bowls and Kewalos handle small (1.5 ft) all the way to overhead. Threes likes 2–4 ft and walls up nicely. Diamond Head wants more south (180°+) and likes the wind. The same 233 reading produces a different wave at each spot — Da Buoys lets you favorite all of them so you can compare in one tap.
Da Buoys puts the South Shore Oahu reading on your iPhone home screen. No subscription, no ads, no signup. Just the buoy.
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