Surf Forecasts:
Asakawa surf forecast from 13 Aug 2026:
- Best quality surf: Friday 14 Aug, 12AM (local time) - 2.5ft (0.7m), 9s period, S swell with glassy winds.
- Most powerful swell: Monday 17 Aug, 3AM (local time) - 3.5ft (1.1m), 10s period, ESE swell with 221 kJ wave energy.
- Next surfable swell (1★+): Friday 14 Aug, 12AM (local time) - 2.5ft (0.7m), 9s period with S 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 Friday (Aug 14) at 12AM. The primary swell is predicted to be 0.7m and 9s period with a secondary swell of 0.3m and 4s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Asakawa in the next 16 days are 1.1m 10s and forecast to arrive on Monday (Aug 17) at 3AM. 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+) | 12AM (Fri 14th Aug) | 2.5ft (0.7m) 9s |
| Best Surf | 12AM (Fri 14th Aug) | 2.5ft (0.7m) 9s |
| Most Powerful | 3AM (Mon 17th Aug) | 3.5ft (1.1m) 10s |
Table - best surf conditions forecast for Asakawa over the next 16 days.
The Lowdown
Alright, Rusty here. Let's have a look at this stretch of water that's been on my mind.
Honestly, for the next week and a half, things are looking pretty flat and uninspiring. You’re looking at small, weak swells with onshore winds messing things up most of the time. It’s a bit of a bummer. The real action, and I mean the *real* action, kicks off about ten days from now.
We start off with Asakawa on Thursday, August 13th. It’s a point break, fairly exposed but the swell is tiny at 2 ft from the SSW, with a period of 9 seconds. The wind is blowing from the S at 6 mph, so it's onshore and messy. The water here is sitting at a warm 84°, which is pretty normal for this time of year. The combined swell energy is weak, only 125, and honestly, there’s not much to get excited about.
Friday morning, August 14th, is the first glimpse of something you could paddle out into. It’s still just 2 ft of S swell at 9 seconds, but the wind goes glassy from the SSE at 3 mph. That’s clean, I’ll give it that. The energy is still only moderate at 110. It’s surfable, just very ordinary.
Saturday morning, August 15th, is much the same: 2 ft S swell, 10-second period, glassy with an ESE breeze at 3 mph. The energy is moderate at 127. Again, clean but small.
The weekend goes downhill after that. Sunday, August 16th, the wind picks up and we get a bump in size to 4 ft from the ESE, but the period drops to a short, weak 5 seconds. That’s junk. The energy climbs to 218, but it’s just wind-slop with onshore winds. Not worth it.
Monday, August 17th through Thursday, August 20th is a real write-off. Swell is small, wind is onshore or cross-onshore, and everything is scored as poor. There’s a stretch of about four days where you’re better off doing something else.
Friday, August 21st brings another chance for a clean, small wave. The morning sees 3 ft from the SSE at 8 seconds with glassy conditions from a light SE breeze at 3 mph. The energy is 120. The afternoon gets interesting: 2 ft from the S but the period stretches to 11 seconds, giving the wave a bit more grunt with the energy at 201, and it’s glassy with a 3 mph S wind. That’s a nice little window.
Now, if you want a standout, you have to wait for Sunday, August 23rd. That’s the one. The morning brings a solid 6 ft swell from the SE, and the period is a beautiful 16 seconds. That’s proper groundswell. The wind is offshore from the N at 3 mph. The combined energy is a massive 2067, strong and powerful. This is excellent surf for experienced surfers. That long period means it’s going to be organized and powerful at this point break.
Monday, August 24th and Tuesday, August 25th are even bigger, with 12 ft to 13 ft swells from the SSE and SE, periods of 16 to 17 seconds, and glassy to clean winds. The energy readings are astronomical, over 6500 and up to 7841. This is expert-only territory. The size is too big for beginners, and the power is immense. The long period and big size mean it could be tricky, because very long-period groundswells at a point break can be a bit unruly, but the conditions are perfect.
Wednesday, August 26th keeps the huge 13 ft to 15 ft swell going, but by the afternoon the wind turns cross-onshore at 6 mph from the S, which will junk it up. The morning is still glassy from the SE at 3 mph, so that’s your window if you’re an expert.
Thursday, August 27th sees the swell drop back down to 5 ft from the ESE with a 12-second period, clean and glassy in the morning. That’s a good, solid day for most surfers. The energy is a moderate 819.
After that, it fades back to flat and small from Friday, August 28th onward.
So, the pick of the litter is easily Sunday, August 23rd through Tuesday, August 26th for the experts. For everyone else, the glassy mornings on Friday, August 21st and Saturday, August 22nd are your best bet for a clean, small wave.
Stay tuned, forecasts can always shift.
Rusty.
Short Range ForecastHeavy rain (total 26mm), heaviest during Sat night. Warm (max 29°C on Sat morning, min 24°C on Thu night). Wind will be generally light. | Days 5-7 Weather SummaryHeavy rain (total 24mm), heaviest during Wed morning. Warm (max 29°C on Mon morning, min 25°C on Sun night). Wind will be generally light. | |||||||||||||||||||
Thu 13 | Friday 14 | Saturday 15 | Sunday 16 | Monday 17 | Tuesday 18 | Wednesday 19 | ||||||||||||||
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) | SSW 9 | S 9 | S 9 | S 9 | S 8 | S 10 | S 9 | S 9 | ESE 5 | ESE 6 | E 10 | ESE 9 | ESE 10 | ESE 10 | ESE 9 | SE 9 | SE 10 | SE 10 | SE 10 | SE 6 |
Wave Graph | ||||||||||||||||||||
86 | 79 | 73 | 73 | 52 | 92 | 79 | 56 | 66 | 80 | 56 | 168 | 137 | 102 | 50 | 40 | 27 | 28 | 26 | 38 | |
Wind (km/h) | ||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | on | glassy | glassy | cross-on | glassy | glassy | on | cross-on | cross-on | on | cross-on | on | on | on | on | on | glassy | cross-on | on | cross |
High Tide | 6:54PM1.83m | 6:24AM1.90m | 7:22PM1.83m | 7:07AM1.87m | 7:49PM1.81m | 7:49AM1.78m | 8:14PM1.77m | 8:31AM1.66m | 8:38PM1.72m | 9:14AM1.51m | 9:01PM1.65m | 10:05AM1.37m | 9:25PM1.57m | |||||||
Low Tide | 00:35AM0.66m | 12:56PM0.09m | 1:12AM0.56m | 1:30PM0.22m | 1:48AM0.49m | 2:00PM0.39m | 2:24AM0.47m | 2:29PM0.58m | 3:02AM0.48m | 2:55PM0.76m | 3:42AM0.53m | 3:19PM0.92m | ||||||||
— | — | 5:22 | — | — | 5:22 | — | — | 5:24 | — | — | 5:24 | — | — | 5:26 | — | — | 5:26 | — | — | |
6:52 | — | — | 6:51 | — | — | 6:49 | — | — | 6:47 | — | — | 6:46 | — | — | 6:45 | — | — | 6:45 | — | |
mm | 3 | 1 | — | 2 | — | — | 1 | 12 | 7 | 2 | 5 | 1 | 2 | 4 | 3 | 1 | 1 | 5 | 3 | — |
Temp °C | 27 | 25 | 28 | 28 | 25 | 29 | 29 | 25 | 26 | 27 | 26 | 29 | 28 | 26 | 27 | 28 | 26 | 28 | 28 | 27 |
Feels °C | 30 | 29 | 30 | 31 | 29 | 32 | 31 | 29 | 28 | 29 | 29 | 31 | 30 | 30 | 30 | 32 | 31 | 33 | 33 | 32 |
Swell 1 Height (m) Direction Period (s) | SSW 9 | S 9 | S 9 | S 9 | S 8 | S 10 | S 9 | S 9 | S 8 | S 9 | S 8 | ESE 9 | ESE 10 | ESE 10 | ESE 9 | SE 9 | SE 5 | SE 5 | SE 5 | SE 6 |
86 | 79 | 73 | 73 | 52 | 92 | 79 | 56 | 51 | 59 | 51 | 168 | 137 | 102 | 50 | 40 | 10 | 18 | 21 | 31 | |
Swell 2 Height (m) Direction Period (s) | E 9 | ESE 4 | ESE 9 | ESE 9 | S 11 | E 10 | E 10 | E 9 | E 10 | E 10 | E 10 | S 8 | S 8 | SSW 8 | SSW 8 | SSW 8 | SE 10 | SE 10 | SE 10 | ESE 10 |
7 | 3 | 17 | 17 | 37 | 17 | 30 | 14 | 52 | 50 | 47 | 34 | 33 | 21 | 20 | 20 | 27 | 26 | 26 | 38 | |
Swell 3 Height (m) Direction Period (s) | SE 12 | E 10 | SE 11 | SE 11 | E 9 | SE 11 | SE 8 | SE 12 | SE 12 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 11 | SE 10 | SSW 8 | SSW 8 | SSW 8 | SSE 9 |
22 | 16 | 20 | 19 | 28 | 18 | 10 | 23 | 49 | 46 | 42 | 19 | 30 | 30 | 30 | 28 | 13 | 12 | 12 | 16 | |
Wind waves Height (m) Direction Period (s) | ESE 4 | — | — | — | — | — | — | ESE 5 | ESE 5 | ESE 6 | ESE 5 | — | — | — | — | SE 4 | — | SE 5 | — | — |
10 | — | — | — | — | — | — | 39 | 66 | 80 | 56 | — | — | — | — | 7 | — | 28 | — | — | |
Nearest Offshore or Glassy | ||||||||||||||||||||
Distance (km) | 14 | 0 | 0 | 11 | 0 | 0 | 19 | 43 | 285 | 303 | 43 | 11 | 11 | 11 | 43 | 19 | 2 | 43 | 14 | 2 |
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.











