Surf Forecasts:
Waimanalo surf forecast from 15 Aug 2026:
- Best quality surf: Sunday 16 Aug, 11AM (local time) - 10ft (3.0m), 9s period, E swell with cross-shore winds.
- Most powerful swell: Sunday 16 Aug, 2AM (local time) - 16ft (5.0m), 10s period, E swell with 5,002 kJ wave energy.
- Next surfable swell (1★+): Sunday 16 Aug, 11AM (local time) - 10ft (3.0m), 9s period with E swell.
Best Forecast Surf Conditions for Waimanalo this week:
The surf forecast for Waimanalo over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Aug 16) at 11AM. The primary swell is predicted to be 3.0m and 9s period. The wind is predicted to be cross-shore as the swell arrives.
The most powerful waves expected at Waimanalo in the next 16 days are 5.0m 10s and forecast to arrive on Sunday (Aug 16) at 2AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.2m 10s period and expected on Sunday (Aug 16) at 8AM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 11AM (Sun 16th Aug) | 10ft (3.0m) 9s |
| Best Surf | 11AM (Sun 16th Aug) | 10ft (3.0m) 9s |
| Most Powerful | 2AM (Sun 16th Aug) | 16ft (5.0m) 10s |
Table - best surf conditions forecast for Waimanalo over the next 16 days.
The Lowdown
Right, strap in, ‘cause it’s looking like a bit of a flat, frustrating stretch ahead for us here at Waimanalo. I’ve got the whole 16-day picture in front of me, and honestly, for the first week or so, it’s a whole lot of nothing. You’re gonna want to find something else to do with your mornings.
We start off on Saturday the 15th with a real mess. There’s a solid bump of swell, around 12 to 13ft, but it’s coming in with a howling onshore wind, near gale force, and the energy is all over the place. It’s not surfable, it’s just chaos. The water’s still warm, no real anomaly there, pretty average for this time of year, but you won’t wanna be in it.
Sunday the 16th is a bit of a cruel tease. The swell drops to a still-too-big 10ft, and the wind swings offshore-ish but it’s a cross-shore. The report says the wind and tide are favorable, but it’s just too much water moving for this break. It’s gonna be a closeout mess, only for the truly desperate or the suicidal. The wave energy is still strong, sitting at 1429, but it’s not working for us.
Then the bottom falls out. From Monday the 17th all the way through to Friday the 22nd, it’s just poor. Swell drops off to 6ft and below, with short, weak periods of 6-8 seconds. The wind is mostly on or cross-onshore, leaving everything chopped and lumpy. There’s a lot of days with zero recommendations, and the energy readings just sink into the weak zone, like 123, 107, 113... It’s a proper flat spell. You’d be better off checking the kite forecast, because with this wind and messy surf, that’s about all it’s good for.
The weekend of the 23rd and 24th shows a tiny pulse of life, with waves back to 5ft and 5ft, but the period is still short and the wind hasn’t sorted itself out. It’s still a “poor surf conditions” call, just a bit of a bigger version of poor.
Now, here’s where it gets interesting. Around the 27th and 28th of August, we start to see a change in the longer range. The swell period jumps way up to 17-18 seconds, which signals a proper groundswell. The energy numbers are getting into the strong zone, like 1041 and 1439. But, and it’s a big but, the wave height is still in the 3-5ft range, and that long period stuff at a beach break like Waimanalo can tend to just surge straight through, not offering much shape. Plus, the wind is still on it, so quality is going to be an issue.
The one true standout in this entire window is looking like Sunday the 30th of August. We’ve got a 8ft ENE swell with a 14-second period, and the energy is cranked way up, hitting 2989. That is some serious juice. This is big for Waimanalo, and with that kind of size, it’s expert territory only. The wind is still onshore, which is a shame, but the raw power is there. It’s a long way out, so I wouldn’t book the time off work just yet, but it’s the first thing all week that’s got my heart rate up. A cleaner day with that kind of energy could be something special. But as it stands, for the next sixteen days, that’s your only real glimmer. It’s going to be a test of patience, that’s for sure.
Rusty.
Short Range ForecastHeavy rain (total 56mm), heaviest during Sat night. Warm (max 27°C on Sun afternoon, min 25°C on Fri night). Winds decreasing (gales from the ENE on Sat night, moderate winds from the ESE by Sun night). | Days 5-7 Weather SummaryMostly dry. Warm (max 26°C on Thu morning, min 25°C on Mon night). Mainly fresh winds. | ||||||||||||||||||
Saturday 15 | Sunday 16 | Monday 17 | Tuesday 18 | Wednesday 19 | Thursday 20 | ||||||||||||||
Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | |
Swell Height Map | |||||||||||||||||||
Wave Height (m) Direction Period (s) | ENE 8 | ENE 9 | E 9 | E 10 | E 9 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | ENE 6 | ENE 6 | ENE 6 | ENE 6 | ENE 7 | E 8 | E 8 | ENE 7 | ENE 7 |
Wave Graph | |||||||||||||||||||
928 | 1938 | 2457 | 5002 | 1423 | 851 | 484 | 365 | 252 | 181 | 122 | 101 | 108 | 104 | 113 | 80 | 78 | 148 | 188 | |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | on | on | cross-on | cross | cross | cross-on | cross-on | on | on | cross-on | on | cross-on | on | on | on | cross-on | on | on |
High Tide | 4:22AM0.43m | 4:30PM0.58m | 5:20AM0.44m | 4:40PM0.52m | 6:27AM0.44m | 4:40PM0.47m | 8:02AM0.45m | 4:17PM0.43m | 10:23AM0.47m | 11:48AM0.51m | |||||||||
Low Tide | 10:33PM0.12m | 10:00AM0.11m | 10:59PM0.09m | 10:41AM0.19m | 11:25PM0.08m | 11:25AM0.27m | 11:52PM0.07m | 12:27PM0.33m | 00:26AM0.08m | 1:15AM0.09m | 2:41AM0.09m | ||||||||
— | 6:09 | — | — | 6:09 | — | — | 6:09 | — | — | 6:09 | — | — | 6:09 | — | — | 6:09 | — | — | |
7:00 | — | 7:00 | — | — | 7:00 | — | — | 6:59 | — | — | 6:58 | — | — | 6:58 | — | — | 6:57 | — | |
mm | — | 1 | 2 | 25 | 16 | 8 | 3 | 1 | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 25 | 26 | 26 | 26 | 26 | 27 | 27 | 25 | 26 | 25 | 25 | 25 | 25 | 25 | 25 | 25 | 26 | 26 | 25 |
Feels °C | 22 | 22 | 21 | 20 | 25 | 27 | 28 | 24 | 27 | 24 | 23 | 23 | 24 | 24 | 25 | 25 | 27 | 27 | 27 |
Swell 1 Height (m) Direction Period (s) | S 14 | S 13 | S 13 | S 14 | SSE 9 | SSE 8 | ENE 8 | S 14 | S 14 | S 13 | S 13 | S 13 | S 13 | NNE 7 | S 12 | E 8 | NE 6 | SSW 18 | ENE 7 |
62 | 55 | 30 | 63 | 222 | 119 | 484 | 103 | 65 | 55 | 54 | 30 | 29 | 15 | 11 | 80 | 43 | 30 | 188 | |
Swell 2 Height (m) Direction Period (s) | NNW 8 | S 20 | NNW 8 | NNW 9 | S 16 | S 16 | S 7 | SSE 6 | S 6 | E 9 | SW 17 | SSE 8 | SSE 7 | S 12 | SSE 9 | NE 6 | SSW 18 | S 12 | SSW 17 |
6 | 7 | 7 | 8 | 47 | 46 | 37 | 13 | 6 | 6 | 11 | 7 | 5 | 11 | 8 | 43 | 31 | 11 | 27 | |
Swell 3 Height (m) Direction Period (s) | SSW 17 | S 20 | S 16 | S 18 | NNW 8 | S 13 | S 13 | N 8 | N 7 | N 7 | N 7 | ENE 8 | SW 18 | SSE 9 | SW 16 | S 12 | S 11 | SE 9 | S 15 |
29 | 30 | 21 | 25 | 6 | 30 | 56 | 4 | 1 | 1 | 1 | 6 | 12 | 8 | 11 | 11 | 10 | 3 | 17 | |
Wind waves Height (m) Direction Period (s) | ENE 8 | ENE 9 | E 9 | E 10 | E 9 | ENE 8 | — | ENE 7 | ENE 7 | ENE 7 | ENE 6 | ENE 6 | ENE 6 | ENE 6 | ENE 7 | — | E 8 | ENE 7 | — |
928 | 1938 | 2457 | 5002 | 1423 | 851 | — | 365 | 252 | 181 | 122 | 101 | 108 | 104 | 113 | — | 78 | 148 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 211 | 212 | 212 | 220 | 51 | 48 | 18 | 44 | 17 | 44 | 44 | 44 | 15 | 44 | 15 | 15 | 44 | 9 | 14 |
Best forecast wave conditions in Oahu | |||||||||||||||||||
Best forecast wave conditions in United States | |||||||||||||||||||
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Information about the Waimanalo Surf forecast
The above surf forecast table for Waimanalo provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Waimanalo can be found by selecting the local surf guide option on the grey menu. Our Waimanalo surf forecast is unique since it includes wave energy (power) that defines the real feel of the surf rather than just the height or the period. If you surf the same spot (Waimanalo) regularly then make a mental note of the wave energy from the surf forecast table each time you go. Very soon you may start to choose your surf days based on the wave energy alone combined with our forecast of favourable offshore wind conditions. Our star ratings will help here and of course you will also find the usual wave height and period predictions on our surf forecasts as well as a full break down of the swell components under our advanced users option (to reveal that, click the little Einstein character under the tide times).
Further information to help with frequently asked questions about our surf forecast for Waimanalo may be found under the help tab on the top menu and also by moving your mouse over the question marks on the surf forecast table itself. Please always bear in mind that the forecast is for near-shore open water and local factors at each surf break influence the actual breaking wave height, such as the beach / reef profile, water depths offshore and shelter.
Waimanalo is 7 km (4 miles) from Kailua. If you plan a vacation in Oahu, look for hotels and other accommodation in Kailua. Kailua has rooms for a wide range of budgets as well as car hire and transport links.











