Number Fours Surf Break

Lat Long: 21.28° N 157.83° W

Number Fours Surf Forecast and Surf Report

Issued: 1 pm 17 Aug 2026 (local time)

Forecast update in  hr  min

Today's Number Fours sea temperature is
27.1° C
0.4° 

Number Fours surf forecast is for near shore open water. Breaking waves will often be smaller at less exposed spots.


Number Fours surf forecast from 18 Aug 2026:

  • Best quality surf: Wednesday 19 Aug, 8PM (local time) - 1.5ft (0.4m), 16s period, SSW swell with cross-offshore winds.
  • Most powerful swell: Monday 24 Aug, 8PM (local time) - 8ft (2.4m), 7s period, ENE swell with 604 kJ wave energy.
  • Next surfable swell (1★+): Wednesday 19 Aug, 8PM (local time) - 1.5ft (0.4m), 16s 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 Wednesday (Aug 19) at 8PM. The primary swell is predicted to be 0.4m and 16s period with a secondary swell of 0.8m and 8s. 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 2.4m 7s and forecast to arrive on Monday (Aug 24) 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 0.9m 7s period and expected on Friday (Aug 21) at 5AM.

Wave TypeTime (HST) & Date Wave Height & Period
Next good surf (1 star+) 8PM (Wed 19th Aug)1.5ft (0.4m) 16s
Best Surf 8PM (Wed 19th Aug)1.5ft (0.4m) 16s
Most Powerful 8PM (Mon 24th Aug)8ft (2.4m) 7s

Table - best surf conditions forecast for Number Fours over the next 16 days.


The Lowdown

G’day, Rusty here. Alright, let’s have a proper look at what’s on the cards for Number Fours.

Right off the bat, the first week or so is a bit of a struggle. We’ve got some swell around, but it’s mostly small and the wind, while cross-offshore, is a persistent moderate breeze that’s keeping things from coming together nicely. The water temp is sitting at a comfortable 81°, which is pretty normal for this time of year.

The first real glimmer of hope shows up on Thursday, the 20th of August. The morning and afternoon both have a clean 2 ft swell from the SSW with a very long period of 17-18 seconds. That’s groundswell energy, and with a light breeze onshore, it’s going to be glassy and clean. The combined swell energy is moderate (322). It’s not big, but for a reef break like Number Fours, that long period and clean surface will make for some fun, lined-up waves. This is the standout of the first week – a sneaky good session for the intermediate surfer who’s paying attention.

After that, it gets a bit messy. Friday the 21st sees the wind shift to a light cross-shore, which will put some small ripples on the face, and the swell drops off again. The weekend of the 22nd and 23rd is a write-off. The wind picks up to a fresh breeze, and on Sunday the 23rd the swell jumps to 6 ft, but it’s a short-period, wind-affected mess from the ENE, giving poor conditions.

Then we hit a long, frustrating stretch. From Monday the 24th all the way through to the end of the month, the swell gets bigger – up to 10 ft by the 28th – but it’s all short-period (7-9 seconds) ENE windswell with a strong to very strong combined energy (up to 1890). The wind stays cross-off but it’s a fresh to strong breeze the whole time. That much short-period energy with that much wind is going to be a churning, bumpy mess. Honestly, that setup looks far more interesting for kite surfing than paddle surfing – it’s going to be blown-out and unruly for a standard board.

The only other small window to keep an eye on is Thursday the 27th and Friday the 28th. The swell hits 10 ft with a period stretching to 9 seconds and energy is very high. It’s marginal at best for paddle surfing given the fresh wind, but if you’re an expert with a lot of patience, it could be a wild, challenging session. For most of us, it’s a skip.

So, bottom line: the best of the lot is that Thursday the 20th. Get out there for the morning or afternoon glass-off. After that, it’s a long, windy gap of poor to marginal conditions until the very end of the forecast period. The break is fairly consistent, so things could change, but right now, it’s a waiting game.

Rusty.

Short Range Forecast

Mostly dry. Warm (max 26°C on Mon afternoon, min 24°C on Mon night). Mainly fresh winds.

Days 5-7 Weather Summary

Mostly dry. Warm (max 27°C on Thu afternoon, min 24°C on Thu night). Winds increasing (light winds from the NE on Thu night, fresh winds from the ENE by Sun morning).

Mon
17
Tuesday
18
Wednesday
19
Thursday
20
Friday
21
Saturday
22
Sunday
23
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
AM
PM
Night
Rating
(10 max)
1
0
0
0
1
1
1
0
2
2
2
1
1
1
1
0
0
0
0
1
Swell
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Height Map
Wave
Height (m)
Direction
Period (s)
0.8
S
14
1.3
ENE
7
0.7
S
13
0.6
S
13
1.2
ENE
8
0.5
SW
16
0.8
E
8
0.5
SW
16
0.6
SSW
18
0.6
SSW
17
0.7
SW
16
0.7
SW
17
0.7
SW
16
0.8
SSW
16
0.7
SW
16
0.7
SW
16
1.9
ENE
7
1.7
ENE
7
1.7
ENE
6
1.8
ENE
7
Wave Graph
Metric surfscale
Energy kJ
260
172
165
136
159
129
100
129
207
200
274
291
261
322
261
255
307
265
207
295
Wind (km/h)
25
ENE
25
ENE
25
ENE
25
ENE
20
ENE
20
ENE
15
ENE
15
NE
15
ENE
10
ENE
5
NE
10
E
10
E
20
ENE
20
ENE
35
ENE
35
ENE
35
ENE
35
NE
30
NE
Wind State
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross
cross
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
cross-off
High Tide
6:52PM0.37m
8:59AM0.51m
7:16PM0.30m
10:13AM0.53m
11:25AM0.56m
10:11PM0.21m
12:25PM0.59m
00:08AM0.21m
1:12PM0.63m
1:06AM0.23m
1:52PM0.66m
1:46AM0.26m
Low Tide
1:27AM0.08m
3:56PM0.27m
2:01AM0.10m
2:47AM0.12m
8:27PM0.20m
8:41PM0.17m
5:06AM0.12m
9:00PM0.16m
6:08AM0.10m
9:18PM0.14m
clear
part cloud
clear
clear
part cloud
part cloud
clear
part cloud
clear
clear
clear
clear
clear
part cloud
clear
clear
clear
clear
clear
part cloud
<span class="translation_missing" title="translation missing: en.weather_tables.sunrise">Sunrise</span>
6:09
6:11
6:11
6:11
6:11
6:11
<span class="translation_missing" title="translation missing: en.weather_tables.sunset">Sunset</span>
7:00
6:59
6:58
6:57
6:57
6:55
6:54
 mm
Temp °C
26
25
25
26
25
25
26
25
26
27
26
26
26
26
26
26
25
26
26
25
Feels °C
26
24
24
23
24
25
27
26
27
29
29
28
28
28
26
24
24
24
24
23
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  • Live Wave Height (m)
  • Live Wind Speed (km/h)
  • Surf Rating (10 Max)
  • Ocean Swells (m)
  • Wind Speed (km/h)
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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.

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