
Surf Forecasts:
Kugenuma Rivermouth surf forecast from 22 Jul 2026:
- Most powerful swell: Wednesday 29 Jul, 12AM (local time) - 1.5ft (0.5m), 8s period, S swell with 35 kJ wave energy.
Best Forecast Surf Conditions for Kugenuma Rivermouth this week:
The most powerful waves expected at Kugenuma Rivermouth in the next 16 days are 0.5m 8s and forecast to arrive on Wednesday (Jul 29) at 12AM. Winds are predicted to be glassy at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.3m 3s period and expected on Monday (Jul 27) at 3AM.
| Wave Type | Time (JST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 12AM (Wed 29th Jul) | 1.5ft (0.5m) 8s |
Table - best surf conditions forecast for Kugenuma Rivermouth over the next 16 days.
The Lowdown
Hey folks, Rusty here. Let’s have a look at what’s coming down the line for the next sixteen days. Honestly, it’s a bit of a slow start. There’s nothing worth paddling out for right now, and we’re looking at a pretty flat run for a while. The first real chance of anything rideable doesn’t show up until the 2nd of August, so that’s over a week of small, weak junk. But hang in there, because things do start to look a little more interesting after that.
The first day with anything worth noting is Sunday morning, August 2nd at Kugenuma Rivermouth. We’ve got a small 1ft swell coming out of the SE with a long period of 16 seconds. The wave energy is still weak, sitting at only 69, and the forecast says “surfable waves but very ordinary conditions”. It’s clean, with a light cross-offshore breeze from the E, so the surface will be nice. But at this size and with that long period, it’s going to be a bit slow and straight-breaking at a river mouth. Not a standout, but something to wet the board.
The real standout of the whole outlook is Monday morning, August 3rd. This is the best we’ve got. Kugenuma Rivermouth sees a bump up to 2ft of swell from the ESE, period of 18 seconds. The combined energy jumps to a moderate 185 – that’s more life in the water. The wind is light from the ENE, keeping it clean. The swell direction (ESE) is a good match for the river mouth’s optimum (S). It’s small but with that long period and glassy conditions, the shape should be better, and the sets will have some push. It’s still a beginner-friendly size, but it’s clean and lined up. The breaks are described as “fairly consistent” but crowds are “often”, so expect company.
After that, Tuesday morning, August 4th offers another clean morning with 1ft from the ESE, a 17-second period, and light wind. The energy is moderate at 119, so it’s worth a look if you missed the Monday. But it’s not as good. After Tuesday afternoon, it drops right back down into tiny, weak surf for the rest of the window.
Overall, it’s a very slow stretch. The only real window is the 2nd through the 4th of August, with Monday morning the 3rd being the pick of the bunch. The water temp is about average for this time of year, no real anomaly to speak of.
Signing off,
Rusty
Short Range ForecastLight rain (total 8mm), mostly falling on Thu night. Warm (max 32°C on Thu morning, min 26°C on Fri night). Wind will be generally light. | Days 5-7 Weather SummaryHeavy rain (total 27mm), heaviest during Sun night. Warm (max 28°C on Sat night, min 23°C on Sun night). Wind will be generally light. | ||||||||||||||||||
Thursday 23 | Friday 24 | Saturday 25 | Sunday 26 | Monday 27 | Tuesday 28 | ||||||||||||||
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) | SSW 5 | SSW 6 | SSW 6 | SSE 10 | SSE 9 | SSE 9 | SE 11 | SE 10 | SE 10 | SSE 15 | SE 15 | SE 11 | SE 11 | SE 10 | SSW 8 | SSW 8 | SSW 9 | SSW 9 | S 8 |
Wave Graph | |||||||||||||||||||
17 | 15 | 13 | 12 | 12 | 11 | 18 | 15 | 15 | 22 | 8 | 18 | 18 | 16 | 22 | 22 | 26 | 26 | 35 | |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | cross-off | cross-on | cross-off | cross-off | on | cross | cross | on | cross-off | cross-off | on | off | cross-off | cross-on | cross | off | cross-on | glassy |
High Tide | 9:55PM1.40m | 10:41PM1.37m | 5:19PM1.20m | 11:42PM1.34m | 5:07PM1.30m | 00:58AM1.34m | 5:24PM1.37m | 2:08AM1.37m | 5:41PM1.41m | 3:05AM1.42m | 5:56PM1.43m | ||||||||
Low Tide | 6:01AM0.51m | 7:24AM0.41m | 6:26PM1.19m | 8:29AM0.31m | 8:49PM1.21m | 9:20AM0.21m | 9:49PM1.18m | 10:02AM0.15m | 10:26PM1.13m | 10:37AM0.11m | 10:54PM1.05m | ||||||||
— | 4:43 | — | — | 4:43 | — | — | 4:43 | — | — | 4:45 | — | — | 4:46 | — | — | 4:47 | — | — | |
6:53 | — | 6:52 | — | — | 6:52 | — | — | 6:52 | — | — | 6:51 | — | — | 6:50 | — | — | 6:49 | — | |
mm | — | — | — | 1 | — | 1 | 3 | 2 | 1 | 9 | — | 2 | 11 | — | — | 4 | — | 1 | — |
Temp °C | 29 | 32 | 31 | 29 | 28 | 28 | 27 | 28 | 28 | 28 | 27 | 28 | 25 | 25 | 26 | 25 | 27 | 27 | 27 |
Feels °C | 32 | 36 | 34 | 33 | 31 | 31 | 31 | 32 | 31 | 32 | 31 | 31 | 27 | 28 | 28 | 27 | 30 | 29 | 31 |
Swell 1 Height (m) Direction Period (s) | SE 11 | SSW 6 | SE 10 | S 5 | S 6 | SSW 7 | SE 11 | SE 10 | SE 10 | SE 10 | SE 15 | SE 11 | SSW 4 | S 5 | SSW 8 | SSW 8 | SSW 9 | SSW 9 | S 8 |
5 | 13 | 4 | 4 | 3 | 5 | 18 | 15 | 15 | 15 | 8 | 18 | 3 | 9 | 22 | 22 | 26 | 26 | 35 | |
Swell 2 Height (m) Direction Period (s) | S 7 | SSE 10 | S 8 | SSE 10 | SSE 9 | SSE 9 | SE 16 | SE 16 | SE 16 | SSE 15 | SE 11 | SE 15 | S 9 | SSW 8 | SE 10 | SE 10 | SSE 10 | SSE 10 | SSE 10 |
1 | 10 | 1 | 9 | 8 | 8 | 10 | 10 | 10 | 22 | 5 | 8 | 14 | 14 | 16 | 16 | 10 | 10 | 9 | |
Swell 3 Height (m) Direction Period (s) | SE 7 | SE 19 | S 19 | SE 18 | SE 18 | SE 17 | S 7 | S 7 | S 7 | S 8 | SE 9 | S 9 | SE 11 | SE 10 | SE 14 | SE 13 | SE 13 | SE 13 | SE 13 |
2 | 15 | 7 | 12 | 12 | 11 | 1 | 1 | 1 | 1 | 3 | 7 | 18 | 16 | 8 | 7 | 7 | 7 | 7 | |
Wind waves Height (m) Direction Period (s) | SSW 5 | — | SSW 6 | — | — | S 2 | SSE 3 | SE 4 | SSE 3 | SE 3 | SSE 4 | S 3 | — | — | — | — | — | — | — |
17 | — | 13 | — | — | 1 | 1 | 3 | 3 | 3 | 1 | 11 | — | — | — | — | — | — | — | |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 84 | 24 | 57 | 57 | 82 | 26 | 30 | 26 | 26 | 57 | 24 | 26 | 57 | 57 | 45 | 30 | 24 | 26 | 2 |
Best forecast wave conditions in Kanagawa | |||||||||||||||||||
Best forecast wave conditions in Japan | |||||||||||||||||||
Header Global | |||||||||||||||||||
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Information about the Kugenuma Rivermouth Surf forecast
The above surf forecast table for Kugenuma Rivermouth provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Kugenuma Rivermouth can be found by selecting the local surf guide option on the grey menu. Our Kugenuma Rivermouth 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 (Kugenuma Rivermouth) 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 Kugenuma Rivermouth 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.










