
Surf Forecasts:
Asakawa surf forecast from 12 Sep 2026:
- Best quality surf: Saturday 19 Sep, 6PM (local time) - 13ft (4.0m), 16s period, SE swell with cross-offshore winds.
- Most powerful swell: Saturday 19 Sep, 6PM (local time) - 13ft (4.0m), 16s period, SE swell with 8,144 kJ wave energy.
- Next surfable swell (1★+): Sunday 13 Sep, 3AM (local time) - 1.5ft (0.4m), 9s period with ESE swell.
Best Forecast Surf Conditions for Asakawa this week:
The surf forecast for Asakawa over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Sunday (Sep 13) at 3AM. The primary swell is predicted to be 0.4m and 9s period with a secondary swell of 0.4m and 7s. Another secondary swell of 0.4m and 4s is also forecast. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Asakawa in the next 16 days are 4.0m 16s and forecast to arrive on Saturday (Sep 19) at 6PM. Winds are predicted to be cross-offshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.6m 4s period and expected on Thursday (Sep 17) at 12PM.
| Wave Type | Time (JST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 3AM (Sun 13th Sep) | 1.5ft (0.4m) 9s |
| Best Surf | 6PM (Sat 19th Sep) | 13ft (4.0m) 16s |
| Most Powerful | 6PM (Sat 19th Sep) | 13ft (4.0m) 16s |
Table - best surf conditions forecast for Asakawa over the next 16 days.
The Lowdown
Alright mate, Rusty here. Let’s have a look at what Asakawa’s got cookin’ for us over the next couple of weeks.
Right off the bat, this first week is a bit of a slow burner. We’ve got a little bump of energy coming through, but the conditions are a proper mixed bag. The standout window is shaping up to be next weekend and into the following Monday, and honestly, that’s where the real magic is.
Let’s start at the beginning. This Sunday the 13th, we’ve got a tiny 2ft swell from the SE with a period of 9 seconds. The wind’s glassy in the morning, but the overall energy is weak (52), making for poor surf. It’s not really worth the paddle.
Monday the 14th sees a slight lift, with 4ft SE swell in the morning under glassy conditions. The energy is getting a bit more moderate at 170, but the period has dropped to 8 seconds, so it’s a bit weak and wobbly. Ordinary is the word.
Tuesday the 15th is your best early shout. We’ve got a clean 4ft SE swell, glassy with zero wind, and the energy is up to a healthy 271. The period is still a short 9 seconds, but for a Tuesday morning session, you’ll get some fun, clean little waves. It’s not a world-beater, but it’s the best of the early stuff.
Then it gets quiet again for a few days, with a bit of a cross-offshore wind on Thursday and Friday the 18th, bringing in a building swell that hits 7ft from the E by the afternoon. The energy jumps to 1181, but the wind is cross-onshore and the conditions look messy. Not your day.
Now, here’s the good stuff. Saturday the 19th morning, we’ve got a 7ft ESE groundswell with a very long 17-second period. The wind is a light cross-offshore from the NE, and the energy is a thumping 3105. The conditions are excellent but this one’s for the experienced crew only – 7ft with that period will be a handful. Saturday afternoon gets even bigger, hitting 13ft from the ESE with the period at 16 seconds. The energy is massive at 7148, but the wind goes a bit cross-shore, and the report flags it as marginal due to tide or shape. It’ll be a beast, but pick your moment.
Sunday the 20th is absolute gold for the big-wave hunters. Morning shows 13ft SE swell with a 13-second period, clean with a cross-offshore breeze. Energy is 5565. Then the afternoon is the real standout: 13ft SE, 14-second period, clean cross-offshore wind, and the energy reading is huge at 8598. The report calls for exceptional conditions for expert surfers. This is the one to circle on the calendar.
Monday the 21st of September is the absolute peak. 20ft SE swell with a 14-second period. The energy reading is a monstrous 13419. The wind is a clean, cross-offshore breeze from the NE. This is big, powerful, serious surf. Only for experienced surfers on proper equipment. The afternoon gets a bit bumpy with rain and cross-onshore wind, so the morning window is the one.
After that, the swell drops off a cliff. Tuesday the 22nd is a write-off with strong onshore wind, and the rest of the week into the following weekend shows tiny, weak swell and poor conditions. There is a slight return of energy on the 27th with a 4ft to 4ft SE groundswell, but the wind goes a bit cross-shore, and it’s only marginal. The last day, the 28th, shows a building 7ft SSE swell with a long period (14 seconds) and heavy rain and cross-shore wind, making it messy.
So, for the standout session: if you’re an experienced surfer, be out there for the morning of Monday the 21st of September. The Saturday and Sunday before are also exceptional, but that Monday morning is the real deal. For the average punter, the best clean, manageable waves will be Tuesday the 15th morning.
Stay safe out there, and don’t get caught inside on that big one.
Rusty.
Short Range ForecastHeavy rain (total 22mm), heaviest during Mon night. Warm (max 29°C on Sun morning, min 23°C on Mon night). Wind will be generally light. | Days 5-7 Weather SummaryHeavy rain (total 26mm), heaviest during Tue night. Warm (max 28°C on Fri afternoon, min 23°C on Tue night). Wind will be generally light. | ||||||||||||||||||
Sunday 13 | Monday 14 | Tuesday 15 | Wednesday 16 | Thursday 17 | Friday 18 | ||||||||||||||
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) | E 14 | SE 9 | SE 9 | SE 9 | SE 8 | SE 8 | SE 10 | SE 9 | SE 9 | SE 9 | ESE 9 | ESE 9 | ESE 9 | SE 9 | SE 8 | ESE 7 | ESE 8 | E 9 | ESE 8 |
Wave Graph | |||||||||||||||||||
35 | 40 | 83 | 145 | 154 | 138 | 262 | 253 | 186 | 155 | 135 | 132 | 96 | 75 | 70 | 316 | 344 | 783 | 346 | |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | glassy | glassy | on | glassy | glassy | cross-on | cross | glassy | on | glassy | glassy | on | glassy | cross-off | cross-off | cross | cross | cross-on | glassy |
High Tide | 6:54AM1.85m | 7:00PM1.83m | 7:31AM1.78m | 7:22PM1.79m | 8:09AM1.67m | 7:43PM1.73m | 8:48AM1.54m | 8:04PM1.66m | 9:32AM1.40m | 8:24PM1.57m | 10:38AM1.28m | 8:45PM1.47m | |||||||
Low Tide | 00:43AM0.33m | 12:57PM0.43m | 1:15AM0.29m | 1:24PM0.57m | 1:46AM0.29m | 1:50PM0.72m | 2:19AM0.34m | 2:13PM0.87m | 2:54AM0.42m | 2:34PM1.00m | 3:36AM0.53m | 2:53PM1.12m | |||||||
— | 5:43 | — | — | 5:43 | — | — | 5:45 | — | — | 5:45 | — | — | 5:46 | — | — | 5:47 | — | — | |
6:14 | — | 6:13 | — | — | 6:10 | — | — | 6:09 | — | — | 6:07 | — | — | 6:07 | — | — | 6:06 | — | |
mm | 4 | 1 | — | 2 | — | 1 | 9 | 3 | 2 | 6 | 2 | 4 | 5 | 2 | 5 | 2 | — | — | — |
Temp °C | 25 | 29 | 29 | 26 | 29 | 28 | 25 | 26 | 27 | 24 | 25 | 25 | 24 | 26 | 26 | 24 | 27 | 28 | 25 |
Feels °C | 30 | 32 | 33 | 31 | 31 | 30 | 29 | 30 | 31 | 29 | 29 | 29 | 28 | 28 | 29 | 27 | 29 | 31 | 29 |
Swell 1 Height (m) Direction Period (s) | S 7 | SE 9 | SE 9 | SE 9 | SE 8 | SE 8 | SE 10 | SE 9 | SE 9 | SE 9 | ESE 9 | ESE 9 | ESE 9 | SE 9 | SE 8 | E 12 | S 11 | ESE 9 | SE 20 |
15 | 40 | 83 | 145 | 154 | 138 | 262 | 253 | 186 | 155 | 135 | 132 | 96 | 75 | 70 | 3 | 2 | 396 | 196 | |
Swell 2 Height (m) Direction Period (s) | ESE 10 | SE 4 | S 7 | E 13 | E 13 | E 12 | E 12 | S 6 | E 13 | E 13 | E 12 | S 7 | E 13 | E 12 | E 12 | E 15 | — | S 10 | S 9 |
35 | 4 | 8 | 29 | 13 | 12 | 12 | 1 | 14 | 12 | 3 | 1 | 3 | 3 | 3 | 4 | — | 2 | 7 | |
Swell 3 Height (m) Direction Period (s) | E 14 | S 7 | E 13 | S 6 | S 7 | S 7 | S 7 | E 15 | S 6 | S 6 | E 14 | S 7 | S 7 | S 7 | S 7 | S 6 | — | — | — |
35 | 8 | 31 | 3 | 3 | 3 | 1 | 17 | 1 | 1 | 4 | 1 | 1 | 1 | 1 | 1 | — | — | — | |
Wind waves Height (m) Direction Period (s) | ESE 4 | — | SE 3 | — | — | — | — | — | — | — | ENE 3 | — | NE 2 | NE 3 | NE 4 | ESE 7 | ESE 8 | E 9 | ESE 8 |
8 | — | 4 | — | — | — | — | — | — | — | 3 | — | 2 | 5 | 6 | 316 | 344 | 783 | 346 | |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 0 | 2 | 11 | 0 | 0 | 11 | 2 | 0 | 19 | 0 | 0 | 11 | 0 | 0 | 0 | 19 | 6 | 41 | 0 |
Best forecast wave conditions in Shikoku | |||||||||||||||||||
Best forecast wave conditions in Japan | |||||||||||||||||||
Header Global | |||||||||||||||||||
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Information about the Asakawa Surf forecast
The above surf forecast table for Asakawa provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Asakawa can be found by selecting the local surf guide option on the grey menu. Our Asakawa 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 (Asakawa) 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 Asakawa 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.
Are you planning a holiday in Shikoku? If you are looking for accommodation near Asakawa, camping, hotels and holiday cottages in Shikoku, consider staying in Anan which is 41 km (25 miles) away. Other places in and around Shikoku where you can find information about places to rent, and car hire include Muroto which is 44 km (27 miles) away, Komatsushima, Aki and Kamojima.










