
Surf Forecasts:
Number Fours surf forecast from 13 Sep 2026:
- Most powerful swell: Thursday 17 Sep, 8PM (local time) - 7.5ft (2.3m), 10s period, ENE swell with 959 kJ wave energy.
Best Forecast Surf Conditions for Number Fours this week:
The most powerful waves expected at Number Fours in the next 16 days are 2.3m 10s and forecast to arrive on Thursday (Sep 17) at 8PM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.7m 6s period and expected on Wednesday (Sep 16) at 8PM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 8PM (Thu 17th Sep) | 7.5ft (2.3m) 10s |
Table - best surf conditions forecast for Number Fours over the next 16 days.
The Lowdown
Alright, folks, Rusty here. Let's talk about what's cookin' at Number Fours over the next couple of weeks.
Honestly, we've got a bit of a wait on our hands. The first proper chance to get wet doesn't really show up until September 18th, with the early part of the run looking pretty lackluster. You'll see some small, clean but weak pulses, but nothing to get excited about. There's a big gap from now until then with no real recommendations.
Our only consistent option on offer is Number Fours, a reef setup that's fairly consistent. Water temp's sitting around 81°, pretty normal for this time of year, so no need to dig out the thick suit.
The real standout here looks to be Friday, September 18th. We've got a clean, cross-off breeze from the ENE at 15 mph and a 3 ft swell from the SSW with a nice 17-second period. That's a proper groundswell. The combined energy is moderate (1247), so there's some push behind it. That long period means it'll shape up well on this reef, with longer lulls between sets making the paddle out a bit easier. It's an intermediate-friendly height, and while crowds are sometimes an issue here, the quality might make it worth sharing a few waves.
Later in the run, around September 24th, we see another pulse of 5 ft from the ENE with a 10-second period, and the combined energy ramps up to strong (1051). Wind stays cross-off and clean. That's a bit more size, but still manageable for most.
A heads-up for September 17th: we've got some bigger, short-period slop showing up – 7 ft from the ENE at 7 seconds – and the combined energy jumps to a very strong 1370. That's a lot of churn, but with that short period and cross-off wind, it's gonna be a messy, closed-out mess. Only for the experts, and even then, not the best quality. The beach-and-reef setup there might actually be better suited for the kite crew that day.
Overall, it's a slow start but there are a couple of windows with decent groundswell and clean conditions to keep an eye on. Stay patient.
- Rusty
Short Range ForecastMostly dry. Warm (max 26°C on Sat afternoon, min 25°C on Sat night). Wind will be generally light. | Days 5-7 Weather SummaryLight rain (total 7mm), mostly falling on Fri morning. Warm (max 27°C on Tue afternoon, min 25°C on Thu night). Mainly fresh winds. | |||||||||||||||||||
Sat 12 | Sunday 13 | Monday 14 | Tuesday 15 | Wednesday 16 | Thursday 17 | Friday 18 | ||||||||||||||
PM | 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) | SW 16 | ENE 9 | SW 15 | SSW 15 | SW 12 | SW 23 | SW 22 | SW 21 | SW 20 | SW 19 | SSW 19 | SW 18 | SSW 18 | SSW 17 | ENE 7 | ENE 10 | ENE 9 | ENE 9 | SSW 17 | SSW 16 |
Wave Graph | ||||||||||||||||||||
124 | 84 | 107 | 84 | 38 | 86 | 227 | 224 | 392 | 384 | 470 | 455 | 541 | 377 | 444 | 898 | 724 | 622 | 580 | 539 | |
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 | cross-off |
High Tide | 4:42PM0.50m | 5:31AM0.57m | 5:11PM0.43m | 6:14AM0.58m | 5:40PM0.36m | 7:02AM0.58m | 6:07PM0.30m | 7:59AM0.57m | 6:32PM0.25m | 9:10AM0.56m | 7:25PM0.21m | 10:27AM0.57m | 11:01PM0.21m | |||||||
Low Tide | 10:56PM0.05m | 11:45AM0.17m | 11:19PM0.06m | 12:45PM0.20m | 11:42PM0.08m | 2:03PM0.23m | 00:07AM0.11m | 4:06PM0.24m | 00:38AM0.13m | 7:14PM0.21m | 1:26AM0.16m | 7:23PM0.18m | 2:56AM0.18m | |||||||
— | — | 6:16 | — | — | 6:18 | — | — | 6:18 | — | — | 6:18 | — | — | 6:18 | — | — | 6:18 | — | — | |
6:37 | — | — | 6:36 | — | — | 6:35 | — | — | 6:34 | — | — | 6:32 | — | — | 6:31 | — | — | 6:30 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 4 | 3 | — | — |
Temp °C | 26 | 26 | 26 | 26 | 25 | 26 | 26 | 25 | 26 | 27 | 26 | 26 | 27 | 26 | 26 | 27 | 26 | 27 | 27 | 26 |
Feels °C | 26 | 26 | 26 | 25 | 25 | 25 | 25 | 25 | 26 | 27 | 26 | 25 | 25 | 26 | 25 | 25 | 25 | 27 | 25 | 25 |
Swell 1 Height (m) Direction Period (s) | NE 9 | NE 9 | NNE 9 | NNE 9 | NE 9 | NE 8 | NE 8 | NNE 8 | SW 20 | SW 19 | SSW 19 | SW 18 | SSW 18 | SSW 17 | SW 16 | SW 16 | SSW 18 | SSW 17 | SSW 17 | SSW 16 |
81 | 112 | 99 | 99 | 79 | 58 | 54 | 44 | 392 | 384 | 470 | 455 | 541 | 377 | 258 | 258 | 644 | 622 | 580 | 539 | |
Swell 2 Height (m) Direction Period (s) | ENE 10 | ENE 9 | SW 15 | SSW 15 | SW 12 | SW 14 | SW 22 | SW 21 | NNE 8 | ENE 6 | NNE 8 | E 10 | SW 11 | SSW 11 | SSW 20 | SSW 19 | SSE 10 | SSE 10 | SSE 7 | SSE 7 |
98 | 84 | 107 | 84 | 38 | 49 | 227 | 224 | 36 | 22 | 22 | 72 | 19 | 12 | 149 | 210 | 9 | 9 | 9 | 18 | |
Swell 3 Height (m) Direction Period (s) | SW 16 | SSW 13 | ENE 9 | SW 12 | ENE 8 | SW 23 | SW 14 | SSW 13 | E 12 | E 12 | E 11 | SW 12 | SW 8 | SW 8 | SSW 11 | SW 10 | SW 10 | W 9 | W 9 | S 20 |
124 | 68 | 26 | 23 | 14 | 86 | 49 | 68 | 46 | 68 | 58 | 35 | 2 | 2 | 11 | 4 | 4 | 2 | 2 | 67 | |
Wind waves Height (m) Direction Period (s) | — | — | E 5 | ENE 9 | ENE 4 | ENE 5 | ENE 5 | ENE 5 | ENE 5 | NE 8 | ENE 5 | ENE 5 | ENE 6 | ENE 6 | ENE 7 | ENE 10 | ENE 9 | ENE 9 | ENE 8 | ENE 8 |
— | — | 10 | 59 | 19 | 25 | 25 | 19 | 30 | 71 | 66 | 80 | 145 | 227 | 444 | 898 | 724 | 616 | 471 | 472 | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 1 | 1 | 31 | 1 | 28 | 31 | 1 | 1 | 1 | 2 | 31 | 31 | 126 | 31 | 39 | 126 | 31 | 39 | 31 | 1 |
Best forecast wave conditions in Oahu | ||||||||||||||||||||
Best forecast wave conditions in United States | ||||||||||||||||||||
Header Global | ||||||||||||||||||||
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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.










