
Surf Forecasts:
Monabe Rivermouth surf forecast from 3 Jul 2026:
- Best quality surf: Tuesday 7 Jul, 9PM (local time) - 10ft (3.0m), 17s period, SE swell with glassy winds.
- Most powerful swell: Friday 10 Jul, 3PM (local time) - 15ft (4.5m), 17s period, S swell with 11,106 kJ wave energy.
- Next surfable swell (1★+): Monday 6 Jul, 6PM (local time) - 3ft (0.9m), 14s period with ESE swell.
Best Forecast Surf Conditions for Monabe Rivermouth this week:
The surf forecast for Monabe Rivermouth over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Monday (Jul 06) at 6PM. The primary swell is predicted to be 0.9m and 14s period with a secondary swell of 0.3m and 7s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Monabe Rivermouth in the next 16 days are 4.5m 17s and forecast to arrive on Friday (Jul 10) at 3PM. Winds are predicted to be onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 1.5m 21s period and expected on Friday (Jul 10) at 12PM.
| Wave Type | Time (JST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 6PM (Mon 6th Jul) | 3ft (0.9m) 14s |
| Best Surf | 9PM (Tue 7th Jul) | 10ft (3.0m) 17s |
| Most Powerful | 3PM (Fri 10th Jul) | 15ft (4.5m) 17s |
Table - best surf conditions forecast for Monabe Rivermouth over the next 16 days.
Updates in hr min s Forecast update imminent
Alright folks, Rusty here with a look at what we’ve got on the cards. This is going to be a real tale of two halves for Monabe-Rivermouth – a whole lot of nothing, then a serious pulse of energy.
First up, we have to wade through a slow start. The water temperature is sitting at about 77°, which is pretty normal for this time of year. From now through the first week of July, it's dead. There’s tiny swell, poor conditions, and nothing worth paddling out for. That's a gap of nearly four days with nothing to recommend.
Things start to stir on Monday the 6th. The combined swell energy climbs to 130 with a tiny 2ft glassy swell from the SE, but it’s still reporting poor conditions. Not enough to get excited about.
Tuesday the 7th is where we finally see a pulse. The early morning glass-off with a 4ft SE groundswell (14 seconds) and a massive jump in combined energy to 1196 should have the river mouth starting to show some shape. The wind is glassy from the WSW, making for clean conditions. This is the first real chance of the run. By the afternoon though, the size jumps to 6ft and the wind swings onshore, getting a bit lumpy.
Now, Wednesday the 8th is for the brave. The swell is pushing 10ft from the SE with a groundswell period of 17 seconds. That’s a lot of water moving. Energy is at 8033 – we are in strong territory. But the wind is cross-onshore, which will muss it up. This is a big, raw ocean.
The real standout is Thursday the 9th and Friday the 10th. Thursday morning brings a clean, glassy 12ft SSE groundswell (16 seconds). The energy is a massive 7130, and the comment is "excellent surf conditions for experienced surfers." That is the call. This is a serious, powerful groundswell with long periods, perfect for a rivermouth setup that can handle that direction. The wind is light and glassy from the SSW. This is the day for the crew who can handle heavy water. Friday the 10th doubles down, with a 13ft morning glass-off from the S. Energy hits 9888. Again, excellent conditions for experienced surfers. If you are an expert, this is your window. But be warned, at this size, it is not for beginners.
The swell drops out fast after that, with a flat Saturday the 11th.
There is a little blip on Sunday the 12th with a 5ft SSE swell, but the conditions are described as "very ordinary." Not worth the mission.
We then see another gap of quiet days until the 16th and 17th. On Thursday the 17th of July, another big SSE groundswell (12ft) is on the cards with a 15-second period and energy of 6110. The wind is onshore though, making it a bit of a power-chop session. It’s more for the charger than the cruiser.
So to sum it up: ignore the first week. The best on offer is Thursday the 9th and Friday the 10th for experienced surfers looking for big, clean, powerful groundswell at the rivermouth. After that, it fades again.
Rusty.
Short Range ForecastModerate rain (total 19mm), heaviest on Fri night. Warm (max 26°C on Fri morning, min 22°C on Sat morning). Wind will be generally light. | Days 4-6 Weather SummaryLight rain (total 9mm), mostly falling on Mon morning. Warm (max 27°C on Tue morning, min 24°C on Mon morning). Wind will be generally light. | ||||||||||||||||||||
Friday 3 | Saturday 4 | Sunday 5 | Monday 6 | Tuesday 7 | Wednesday 8 | Thursday 9 | |||||||||||||||
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) | ESE 8 | ESE 9 | ESE 9 | ESE 9 | ESE 9 | ESE 9 | SE 11 | SE 9 | SE 9 | SE 15 | SE 14 | SE 13 | SE 14 | SE 18 | SE 17 | SE 17 | SE 17 | SSE 16 | SSE 16 | SSE 16 | S 16 |
Wave Graph | |||||||||||||||||||||
28 | 28 | 32 | 16 | 16 | 15 | 30 | 19 | 14 | 109 | 297 | 458 | 612 | 1741 | 4284 | 5128 | 6797 | 3871 | 5815 | 6988 | 8381 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | glassy | on | glassy | cross-on | cross-on | glassy | on | glassy | off | glassy | on | glassy | glassy | on | glassy | cross-on | cross-on | glassy | glassy | on | off |
High Tide | 8:41PM1.67m | 7:51AM1.66m | 9:12PM1.66m | 8:32AM1.60m | 9:43PM1.66m | 9:21AM1.52m | 10:18PM1.64m | 10:22AM1.43m | 10:58PM1.62m | 11:42AM1.36m | 11:45PM1.60m | 1:23PM1.36m | 00:42AM1.59m | ||||||||
Low Tide | 1:57PM0.23m | 2:15AM0.88m | 2:30PM0.30m | 2:55AM0.84m | 3:04PM0.40m | 3:40AM0.80m | 3:41PM0.52m | 4:32AM0.75m | 4:25PM0.67m | 5:34AM0.68m | 5:20PM0.83m | 6:45AM0.58m | 6:35PM0.98m | ||||||||
4:58 | — | — | 4:58 | — | — | 4:58 | — | — | 5:00 | — | — | 5:00 | — | — | 5:01 | — | — | 5:01 | — | — | |
— | 7:17 | — | — | 7:17 | — | — | 7:17 | — | — | 7:17 | — | — | 7:17 | — | — | 7:17 | — | — | 7:16 | — | |
mm | — | — | 7 | 3 | 3 | — | 2 | 3 | 1 | 2 | 2 | — | — | 1 | 2 | 2 | — | — | — | — | — |
Temp °C | 26 | 25 | 23 | 23 | 23 | 24 | 26 | 23 | 24 | 24 | 26 | 24 | 27 | 26 | 25 | 25 | 25 | 24 | 26 | 26 | 24 |
Feels °C | 29 | 28 | 27 | 26 | 27 | 28 | 30 | 27 | 28 | 28 | 29 | 28 | 30 | 29 | 30 | 29 | 29 | 28 | 28 | 29 | 28 |
Swell 1 Height (m) Direction Period (s) | SSW 6 | SSW 6 | ESE 9 | ESE 9 | SE 4 | SSW 6 | SSW 6 | SSW 6 | SSW 6 | SE 15 | SE 14 | SE 13 | SE 14 | SE 18 | SE 17 | SE 17 | SE 17 | SSE 16 | SSE 16 | SSE 16 | S 16 |
48 | 28 | 32 | 16 | 14 | 85 | 66 | 47 | 18 | 109 | 297 | 458 | 612 | 1741 | 4284 | 5128 | 6797 | 3871 | 5815 | 6988 | 8381 | |
Swell 2 Height (m) Direction Period (s) | ESE 8 | ESE 9 | SW 6 | SSW 5 | ESE 9 | ESE 9 | SE 11 | SE 9 | ESE 8 | SSW 6 | SSW 5 | SW 5 | SE 18 | SE 13 | E 8 | SSE 19 | — | SSE 18 | S 21 | — | — |
28 | 28 | 8 | 5 | 16 | 15 | 30 | 19 | 14 | 12 | 11 | 7 | 552 | 473 | 19 | 2876 | — | 1825 | 1254 | — | — | |
Swell 3 Height (m) Direction Period (s) | ESE 12 | ESE 12 | SSE 5 | ESE 12 | ESE 12 | E 4 | ESE 9 | E 4 | SE 9 | ESE 10 | S 7 | S 7 | SW 6 | SSW 6 | — | — | — | E 8 | — | — | — |
14 | 14 | 5 | 14 | 14 | 3 | 15 | 3 | 14 | 21 | 4 | 1 | 18 | 12 | — | — | — | 84 | — | — | — | |
Wind waves Height (m) Direction Period (s) | ENE 5 | ENE 4 | — | ESE 3 | SSW 5 | — | — | — | — | — | — | ESE 3 | E 4 | E 6 | ESE 5 | ESE 5 | E 8 | — | E 8 | ESE 8 | — |
2 | 2 | — | 2 | 3 | — | — | — | — | — | — | 6 | 32 | 88 | 48 | 29 | 107 | — | 61 | 107 | — | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 9 | 238 | 42 | 288 | 47 | 9 | 9 | 9 | 302 | 9 | 9 | 0 | 0 | 50 | 0 | 20 | 75 | 0 | 0 | 75 | 0 |
Best forecast wave conditions in Shikoku | |||||||||||||||||||||
Best forecast wave conditions in Japan | |||||||||||||||||||||
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)
Information about the Monabe Rivermouth Surf forecast
The above surf forecast table for Monabe Rivermouth provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Monabe Rivermouth can be found by selecting the local surf guide option on the grey menu. Our Monabe 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 (Monabe 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 Monabe 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.
Monabe Rivermouth is 11 km (7 miles) from the city of Aki. If you plan a holiday in Shikoku, look for hotels and other accommodation in Aki. Aki has rooms for a wide range of budgets as well as car hire and transport links.










