
Surf Forecasts:
Kugenuma Rivermouth surf forecast from 7 Jul 2026:
- Best quality surf: Wednesday 8 Jul, 3AM (local time) - 4.5ft (1.3m), 16s period, SSE swell with glassy winds.
- Most powerful swell: Saturday 11 Jul, 12AM (local time) - 7ft (2.2m), 16s period, SSW swell with 2,368 kJ wave energy.
- Next surfable swell (1★+): Tuesday 7 Jul, 3PM (local time) - 3.5ft (1.0m), 15s period with SSE swell.
Best Forecast Surf Conditions for Kugenuma Rivermouth this week:
The surf forecast for Kugenuma Rivermouth over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Tuesday (Jul 07) at 3PM. The primary swell is predicted to be 1.0m and 15s period with a secondary swell of 0.3m and 20s. The wind is predicted to be cross-offshore as the swell arrives.
The most powerful waves expected at Kugenuma Rivermouth in the next 16 days are 2.2m 16s and forecast to arrive on Saturday (Jul 11) at 12AM. Winds are predicted to be onshore at the time the swell arrives.
| Wave Type | Time (JST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 3PM (Tue 7th Jul) | 3.5ft (1.0m) 15s |
| Best Surf | 3AM (Wed 8th Jul) | 4.5ft (1.3m) 16s |
| Most Powerful | 12AM (Sat 11th Jul) | 7ft (2.2m) 16s |
Table - best surf conditions forecast for Kugenuma Rivermouth over the next 16 days.
Updates in hr min s Forecast update imminent
Alright folks, Rusty here. Let's have a look at what's on the menu for Kugenuma Rivermouth over the next couple of weeks. It's a bit of a mixed bag, so let's get into it.
The week starts off with a bit of hope. Tuesday morning, July 7th, sees a clean 2ft swell from the SSE with a very long 15-second period. The wind is light offshore from the NNE, so expect clean lines. The combined energy is weak (287), so it's not going to be a big day, but it's our best chance for a clean, small-wave session to kick things off. The water temp is sitting at 75°, which is just a shade cooler than average for this time of year—nothing to worry about.
Tuesday afternoon gets a little bigger at 3ft, but the wind swings cross-offshore from the east, keeping things workable with the wave energy climbing to moderate (518). Wednesday morning, July 8th, brings even more size at 5ft with that same long 16-second period, but the wind goes cross-shore from the ESE. The combined energy jumps to strong (1094), but conditions are described as marginal, so don't expect perfection.
From Wednesday afternoon right through most of next week, things go downhill. The wind locks in from the south, mostly onshore, and the swell fluctuates between 4ft and 7ft. The onshore breeze is going to chop things up, making it pretty average. The energy gets strong, peaking at 2699 on Friday afternoon, July 10th, with a 7ft S swell, but with 16 mph onshore wind, it’s going to be a messy, blown-out mess. Honestly, for a river-mouth setup, that combo looks more interesting for kite surfing than paddle surfing.
Then we hit a real dry spell. From Monday, July 13th, onwards, the swell drops right off. Monday morning has a small window of glassy 3ft SSW swell with no wind, but it's inconsistent and the energy is weak (191). After that, it's day after day of tiny surf, poor conditions, and onshore winds. This lull stretches right through to the end of the third week of July.
Now, there is a flicker of life on the horizon. On Sunday, July 19th, we see a bump back up to 6ft from the S with a 14-second period, pushing energy levels up to a strong 1426. But again, the wind is onshore from the south at 9 mph, so it'll be messy and choppy. It's too far out to get excited about, but it's something to keep an eye on.
To be honest, for this 16-day run, the only standout is that Tuesday morning, July 7th session at Kugenuma Rivermouth. It’s small, but clean and offshore. Everything else is a fight against the wind or waiting for the swell to come back. A tough outlook, but that's how it goes sometimes.
Rusty.
Short Range ForecastMostly dry. Warm (max 25°C on Tue afternoon, min 22°C on Tue night). Wind will be generally light. | Days 4-6 Weather SummaryMostly dry. Warm (max 26°C on Sat afternoon, min 23°C on Fri night). Winds decreasing (fresh winds from the S on Sat afternoon, light winds from the SW by Sun night). | ||||||||||||||||||||
Tuesday 7 | Wednesday 8 | Thursday 9 | Friday 10 | Saturday 11 | Sunday 12 | Monday 13 | |||||||||||||||
AM | 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) | SSE 15 | SSE 15 | SSE 16 | SSE 16 | SSE 16 | SSE 14 | SSE 14 | SSE 14 | S 15 | S 14 | S 16 | SSW 16 | SSW 17 | SSW 16 | SSW 16 | SSW 15 | SSW 14 | SSW 12 | SSW 12 | S 11 | SSW 11 |
Wave Graph | |||||||||||||||||||||
201 | 443 | 328 | 1094 | 1055 | 980 | 799 | 799 | 1344 | 902 | 2027 | 2368 | 2215 | 1872 | 1245 | 892 | 585 | 245 | 161 | 313 | 69 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | off | cross-off | cross-off | cross | on | on | on | on | on | on | on | on | on | on | on | on | on | on | glassy | on | on |
High Tide | 10:05AM1.06m | 10:14PM1.37m | 12:11PM1.00m | 10:59PM1.35m | 3:26PM1.08m | 11:50PM1.34m | 4:34PM1.21m | 00:46AM1.35m | 5:09PM1.30m | 1:43AM1.37m | 5:36PM1.36m | 2:36AM1.41m | 5:58PM1.39m | ||||||||
Low Tide | 3:25PM0.75m | 5:51AM0.57m | 4:12PM0.92m | 7:08AM0.45m | 5:54PM1.07m | 8:11AM0.33m | 7:54PM1.15m | 9:03AM0.22m | 9:11PM1.17m | 9:46AM0.13m | 10:00PM1.16m | 10:23AM0.07m | 10:36PM1.12m | ||||||||
4:33 | — | — | 4:33 | — | — | 4:33 | — | — | 4:35 | — | — | 4:35 | — | — | 4:35 | — | — | 4:35 | — | — | |
— | 7:00 | — | — | 7:00 | — | — | 6:59 | — | — | 6:59 | — | — | 6:59 | — | — | 6:58 | — | — | 6:58 | — | |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | — |
Temp °C | 24 | 25 | 23 | 24 | 25 | 24 | 25 | 25 | 24 | 25 | 25 | 24 | 25 | 26 | 25 | 26 | 26 | 25 | 26 | 27 | 25 |
Feels °C | 23 | 25 | 24 | 25 | 25 | 25 | 26 | 25 | 25 | 25 | 24 | 24 | 25 | 25 | 25 | 26 | 25 | 26 | 30 | 29 | 27 |
Swell 1 Height (m) Direction Period (s) | SSE 15 | SSE 15 | SSE 14 | SSE 16 | SSE 16 | SSE 14 | SSE 14 | SSE 14 | S 15 | S 14 | S 16 | SSW 16 | SSW 17 | SSW 16 | SSW 16 | SSW 15 | SSW 14 | SSW 12 | SSW 12 | SSE 10 | SSW 11 |
201 | 443 | 328 | 1094 | 1055 | 980 | 799 | 799 | 1344 | 902 | 2027 | 2368 | 2215 | 1872 | 1245 | 892 | 585 | 245 | 161 | 9 | 69 | |
Swell 2 Height (m) Direction Period (s) | SE 12 | SSE 20 | SSE 16 | — | S 18 | ESE 8 | S 19 | S 18 | ESE 8 | SSW 18 | SSW 21 | SE 10 | — | — | — | SSE 10 | SE 10 | SSE 9 | SSE 10 | SE 10 | SE 9 |
86 | 75 | 310 | — | 422 | 25 | 184 | 509 | 21 | 655 | 672 | 100 | — | — | — | 10 | 28 | 8 | 9 | 16 | 3 | |
Swell 3 Height (m) Direction Period (s) | WSW 6 | — | — | — | — | — | ESE 8 | — | — | — | — | — | — | — | — | SE 14 | E 9 | SE 13 | SE 13 | ESE 9 | SE 12 |
4 | — | — | — | — | — | 26 | — | — | — | — | — | — | — | — | 8 | 6 | 7 | 7 | 16 | 6 | |
Wind waves Height (m) Direction Period (s) | NNE 3 | — | — | — | — | — | — | — | — | — | — | — | — | S 4 | SSW 4 | — | S 4 | SSW 4 | SSW 4 | S 11 | SSW 4 |
3 | — | — | — | — | — | — | — | — | — | — | — | — | 18 | 11 | — | 27 | 24 | 14 | 313 | 25 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 0 | 0 | 0 | 8 | 26 | 7 | 26 | 84 | 7 | 26 | 85 | 7 | 85 | 85 | 7 | 137 | 484 | 7 | 0 | 85 | 7 |
Best forecast wave conditions in Kanagawa | |||||||||||||||||||||
Best forecast wave conditions in Japan | |||||||||||||||||||||
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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.










