Surf Forecasts:
Number Fours surf forecast from 10 Sep 2026:
- Best quality surf: Wednesday 16 Sep, 2AM (local time) - 2.5ft (0.8m), 19s period, SSW swell with cross-offshore winds.
- Most powerful swell: Wednesday 16 Sep, 5PM (local time) - 3ft (0.9m), 18s period, SSW swell with 541 kJ wave energy.
- Next surfable swell (1★+): Thursday 10 Sep, 2AM (local time) - 2.5ft (0.7m), 13s period with SSW swell.
Best Forecast Surf Conditions for Number Fours this week:
The surf forecast for Number Fours over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Thursday (Sep 10) at 2AM. The primary swell is predicted to be 0.7m and 13s period with a secondary swell of 1.1m and 8s. Another secondary swell of 0.7m and 13s is also forecast. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Number Fours in the next 16 days are 0.9m 18s and forecast to arrive on Wednesday (Sep 16) at 5PM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.1m 9s period and expected on Sunday (Sep 13) at 8PM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 2AM (Thu 10th Sep) | 2.5ft (0.7m) 13s |
| Best Surf | 2AM (Wed 16th Sep) | 2.5ft (0.8m) 19s |
| Most Powerful | 5PM (Wed 16th Sep) | 3ft (0.9m) 18s |
Table - best surf conditions forecast for Number Fours over the next 16 days.
The Lowdown
Alright, Rusty here.
Let’s talk about Number Fours. The next couple of weeks is a real mixed bag. There’s energy in the water pretty often, but the wind keeps getting in the way, and most days are looking marginal or just plain poor. There is one golden window in the middle of the month that’s got my attention.
We start on Thursday the 10th of September. Morning has some waist-to-chest high sets at 5ft from the ENE. Wind is a cross-offshore at 12 mph, so the surface is clean, but the swell period is a short 7 seconds and the energy is moderate. It’s barely rideable. The afternoon gets windier at 19 mph and it’s a washout.
Friday the 11th is a step up towards the afternoon. After a flat morning, we get 4ft surf from the East with a proper 11-second period, giving it some punch. The wind is a clean cross-off at 12 mph. It’s still marginal, but it’s the best of the early stuff.
Then it drops right off. Tiny, poor conditions from Saturday the 12th through Monday the 14th.
The real standout is Tuesday the 15th of September. This is the one to mark on the calendar. The guidance says this reef loves a SSE swell, and we’re gettin’ a long-period groundswell from the SW at 20 seconds. The height is only 2ft, but with that kind of period, the wave shape and quality will be way better than the size suggests. The wave energy is solid at a moderate level. Winds are light—only 6 mph from the East in the morning and 9 mph from the ENE in the afternoon. It’s clean, glassy, and has that deep ocean push. This reef will handle it perfectly. Just know that crowds can happen here sometimes.
After that, Wednesday the 16th still has 3ft surf with an 18-second period and good energy, but the wind picks up and brings some cross-chop in the morning.
From Thursday the 17th through the end, the wind cranks to 22-25 mph from the ENE every day. The swell is still there, but it’s a blustery mess for paddling. That stretch might be better for kite surfing than a regular surfboard.
So, the long and short of it: the first few days are tough. The only real highlight, the one you should hold out for, is Tuesday the 15th of September at Number Fours. That long-period groundswell with light winds is gonna be worth the patience.
Keep your eyes peeled.
Rusty.
Short Range ForecastSome drizzle, heaviest during Wed night. Warm (max 27°C on Wed night, min 24°C on Fri night). Winds increasing (light winds from the NE on Wed night, fresh winds from the ENE by Thu afternoon). | Days 5-7 Weather SummaryMostly dry. Warm (max 27°C on Mon afternoon, min 25°C on Sat night). Wind will be generally light. | ||||||||||||||||||
Thursday 10 | Friday 11 | Saturday 12 | Sunday 13 | Monday 14 | Tuesday 15 | ||||||||||||||
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) | E 13 | ENE 7 | ENE 7 | SW 16 | ENE 11 | E 11 | SW 15 | SW 15 | ENE 10 | ENE 9 | SW 15 | SSW 15 | SW 12 | SW 23 | SW 22 | SW 21 | SW 20 | SW 19 | SSW 19 |
Wave Graph  | |||||||||||||||||||
 kJ | 176 | 203 | 188 | 268 | 387 | 286 | 227 | 242 | 125 | 84 | 107 | 84 | 38 | 86 | 227 | 224 | 392 | 384 | 470 |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off | cross-off |
High Tide | 3:32AM0.45m | 3:39PM0.64m | 4:11AM0.50m | 4:12PM0.57m | 4:51AM0.54m | 4:42PM0.50m | 5:31AM0.57m | 5:11PM0.43m | 6:14AM0.58m | 5:40PM0.36m | 7:02AM0.58m | 6:07PM0.30m | |||||||
Low Tide | 9:46PM0.05m | 9:12AM0.07m | 10:10PM0.04m | 10:02AM0.10m | 10:33PM0.04m | 10:52AM0.13m | 10:56PM0.05m | 11:45AM0.17m | 11:19PM0.06m | 12:45PM0.20m | 11:42PM0.08m | 2:03PM0.23m | 00:07AM0.11m | ||||||
 |  | |  |  | |  | | | | | | | | | | | | | |
 | — | 6:16 | — | — | 6:16 | — | — | 6:16 | — | — | 6:16 | — | — | 6:18 | — | — | 6:18 | — | — |
 | 6:39 | — | 6:38 | — | — | 6:37 | — | — | 6:37 | — | — | 6:36 | — | — | 6:35 | — | — | 6:34 | — |
mm | 1 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
Temp °C | 27 | 26 | 27 | 26 | 26 | 26 | 25 | 26 | 26 | 25 | 26 | 26 | 25 | 26 | 27 | 26 | 27 | 27 | 27 |
Feels °C | 30 | 27 | 26 | 26 | 25 | 25 | 24 | 26 | 25 | 25 | 25 | 24 | 24 | 26 | 27 | 27 | 30 | 30 | 30 |
Swell 1 Height (m) Direction Period (s) | ENE 8 | ENE 7 | ENE 7 | SW 16 | ENE 11 | E 11 | ENE 10 | ENE 10 | ENE 10 | NNE 9 | NNE 9 | NE 9 | NE 9 | NE 8 | NE 8 | NE 8 | NE 8 | NE 8 | SSW 19 |
| kJ | 138 | 203 | 188 | 268 | 387 | 286 | 227 | 128 | 125 | 99 | 99 | 79 | 79 | 82 | 54 | 119 | 79 | 67 | 470 |
Swell 2 Height (m) Direction Period (s) | E 13 | E 12 | SSW 12 | E 11 | SW 16 | SW 15 | SW 15 | NE 9 | NE 9 | ENE 9 | E 9 | SSW 15 | SW 12 | SW 14 | SW 22 | SW 21 | SW 20 | SW 19 | E 7 |
| kJ | 156 | 141 | 121 | 93 | 261 | 229 | 226 | 75 | 81 | 84 | 57 | 84 | 38 | 49 | 227 | 224 | 392 | 384 | 39 |
Swell 3 Height (m) Direction Period (s) | SSW 13 | SSW 13 | E 12 | S 12 | NNE 8 | NNE 8 | NNE 8 | SW 15 | SW 16 | SSW 13 | SW 15 | SW 12 | ENE 8 | SW 23 | SW 14 | SW 13 | ESE 7 | E 7 | E 11 |
| kJ | 176 | 133 | 101 | 69 | 26 | 51 | 40 | 242 | 124 | 68 | 107 | 37 | 14 | 86 | 49 | 44 | 16 | 27 | 37 |
Wind waves Height (m) Direction Period (s) | — | — | — | ENE 7 | — | — | NNE 8 | — | — | — | — | ENE 9 | ENE 6 | ENE 5 | ENE 5 | — | — | — | NE 7 |
| kJ | — | — | — | 162 | — | — | 76 | — | — | — | — | 59 | 47 | 42 | 33 | — | — | — | 64 |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 0 | 31 | 32 | 1 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 13 | 1 | 1 | 0 | 0 | 0 | 0 |
Best forecast wave conditions in Oahu | |||||||||||||||||||
Best forecast wave conditions in United States | |||||||||||||||||||
Header Global | |||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Number Fours surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
Information about the Number Fours Surf forecast
The above surf forecast table for Number Fours provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Number Fours can be found by selecting the local surf guide option on the grey menu. Our Number Fours 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 (Number Fours) 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 Number Fours 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.
Number Fours is 5 km (3 miles) from Honolulu. If you plan a vacation in Oahu, look for hotels and other accommodation in Honolulu. Honolulu has rooms for a wide range of budgets as well as car hire and transport links.
Nearest