Swell direction
NNW to NW (315°–340°)
North Shore · Oahu
The original big-wave proving ground. Sleeping until it isn't.
Get Waimea Bay live dataFreeBuoy CDIP 106 · Waimea Bay, Oahu
Waimea Bay sits on the North Shore of Oahu and is the most famous big-wave spot in surfing history — home of the Eddie Aikau Big Wave Invitational. Most days the bay is a postcard-perfect swimming beach. A few days a year it turns into a 30-foot-face wall that decides who paddles out and who watches from the cliff. The CDIP buoy 106 sitting offshore is the most-watched single piece of weather instrumentation in surf.
What you want to see on the buoy before you paddle out.
Swell direction
NNW to NW (315°–340°)
Swell period
14–18 seconds
When it breaks
Bay wakes up around 8 ft @ 14 s. The Eddie runs at 20 ft Hawaiian (~40 ft face).
Wind
Light trades (E to ENE) or offshore (S to SSE). Kona winds shut it down.
Hawaiian scale measures wave back, not face. A 'Hawaiian 15-foot day' at Waimea is a ~30-foot face. Buoy reading and Hawaiian size aren't 1:1 — the bay funnels and amplifies long-period north swell.
When 106 reads above 6 ft @ 14 s with a NNW–NW direction, the bay starts to wake up. 10 ft @ 16 s = solid, paddle-out crowd. 15 ft @ 18 s NW = Eddie territory; you should be on the cliff, not in the water, unless you're invited. Period matters more than height — short-period north swells under 12 s close out the bay before they break.
When 106 shows 18+ ft and the bay is closed out (whitewash from cliff to cliff), Da Buoys lets you flip to neighboring buoys (Mokapu, Hanalei) to see if outer reefs are running cleanly. The widget on your home screen tells you in a glance whether the swell has peaked or is still building.
Da Buoys puts the Waimea Bay reading on your iPhone home screen. No subscription, no ads, no signup. Just the buoy.
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