Oʻahu, United States · Pacific/Honolulu
Waikiki
Long, slow, shallow. Peel speed is the whole game here, and peel speed is depth, and depth is tide.
19:00 local · 2026-10-04
63% — the read for this hour
Swell
0.66 m
Period
8 s
Swell from
119°
Wind
5.3 m/s
Wind from
53°
Air
24°C
Worth the drive. At Waikiki on this hour the read is 63%. What earns it: peel speed at 11.8 km/h. What costs it: swell power at 2.2 kW/m.
24 hours worth driving for today: 00:00, 01:00, 02:00, 03:00, 04:00, 05:00, 06:00, 07:00, 08:00, 09:00, 10:00, 11:00, 12:00, 13:00, 14:00, 15:00, 16:00, 17:00, 18:00, 19:00, 20:00, 21:00, 22:00, 23:00.
Tide window for a reef: 0.6–1.4 m of water over the take-off; below 0.40 m it wants the reef just covered matters and the reef is exposed.
Dashed line is the tide above MLLW, solid line is the swell height. Column height is the engine score for that hour. Faded columns are gated. The hour you select is in the URL, so this page is shareable as-is.
Tide station
- Station
- Honolulu, Oʻahu
- Datum
- MLLW
- Range
- 0.58 m
- Mean
- 0.30 m
Signature interaction
Drag the tide and watch the reef change its mind
The cross-section is drawn from the break's own reef slope. Every change re-runs the shared engine on the server and returns a fresh seal — this control cannot work without the API.
The dashed arrow is the peel, at c = √(g·depth). More water over the take-off means a faster peel, which is why the same swell behaves differently at low and mid tide.
Re-solved by swellread-engine/2026.10.1
- Water over take-off
- exposed
- Break height
- 0.31 m
- Peel speed
- 11.8 km/h
- Wave power
- 2.2 kW/m
Worth the drive. At Waikiki on this hour the read is 63%. What earns it: peel speed at 11.8 km/h. What costs it: swell power at 2.2 kW/m.
Every factor, re-weighted for this tide
- Swell power2.2 kW/m · 2.2%
- Peel speed11.8 km/h · 20.0%
- Wind quality5.3 m/s 66° off · 5.9%
- Tide window1.09 m over the take-off · 18.0%
- Direction match7° off the 112° peel · 12.0%
- Period cleanliness8.0 s · 4.7%
Show your working
Every factor, its weight, and the arithmetic behind it
Weights are renormalised over the factors that have real data behind them. A factor with no data is dropped and said so, never quietly scored at zero.
- Swell power2.2 kW/m · 2.2%
weight 0.220
- Peel speed11.8 km/h · 20.0%
weight 0.200
- Wind quality5.3 m/s 66° off · 5.9%
weight 0.200
- Tide window1.09 m over the take-off · 18.0%
weight 0.180
- Direction match7° off the 112° peel · 12.0%
weight 0.120
- Period cleanliness8.0 s · 4.7%
weight 0.080
engine seal c978a31a0b0ba072541f042b476fdbe11f65368d9021edf3c45e41a28c68a6080d5043628560121e5d35d13380a15fb7
Swell power
P = 1/16 · rho · g · Hs² · Tp = 0.628 · 0.66² · 8 = 2.2 kW/m, against a 22 kW/m "serious day" reference.
Peel speed
c = sqrt(g · depth) = sqrt(9.81 · 1.09 m) = 11.8 km/h over a 1.09 m take-off, with 0.31 m standing up. Full marks 8.5–19 km/h: slower is mush, faster than ~25 km/h is unridable.
Wind quality
Wind is 66° off at 5.3 m/s. Alignment = 1 − (1 + cos 66°)/2 = 0.30; speed envelope at 5.3 m/s = 1.00. Product 0.30.
Tide window
reef wants the reef just covered. Ideal band 0.6–1.4 m of water over the take-off; below 0.40 m the reef is exposed.
Direction match
Swell from 119°, this break peels cleanly from 112°. 7° of error: inside 12° is full marks, past 75° the swell wraps the headland and does not arrive.
Period cleanliness
Tp = 8.0 s. Energy organises between 6 s and 9.5 s; beyond 14 s the swell stands up steeper than a shallow reef can hold, so the score is eased off by up to 35%.
Provenance
Every number above came from one of these
- liveOpen-Meteo Marine APICC BY 4.0, non-commercial attribution requiredfetched 2026-10-04 21:10 UTC168 hourly rows, swell and wind wave.
- liveOpen-Meteo Forecast APICC BY 4.0, non-commercial attribution requiredfetched 2026-10-04 21:10 UTC168 hourly rows, wind and air.
- liveNOAA CO-OPS tide predictionsU.S. Government public domainfetched 2026-10-04 21:10 UTC144 hourly predictions, MLLW datum, station 1611400 (Honolulu, Oʻahu).
Snapshot generated 2026-10-04T21:10:32.169Z. Break orientation, reef slope and take-off depth come from this project's catalogue and are labelled as estimates, not survey data.