Surf Forecasts:
Ammonias surf forecast from 22 Aug 2026:
- Most powerful swell: Thursday 27 Aug, 2PM (local time) - 3.5ft (1.1m), 17s period, S swell with 702 kJ wave energy.
Best Forecast Surf Conditions for Ammonias this week:
The most powerful waves expected at Ammonias in the next 16 days are 1.1m 17s and forecast to arrive on Thursday (Aug 27) at 2PM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.6m 10s period and expected on Saturday (Aug 22) at 8AM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 2PM (Thu 27th Aug) | 3.5ft (1.1m) 17s |
Table - best surf conditions forecast for Ammonias over the next 16 days.
The Lowdown
Alright surfers, Rusty here. Let's get into it.
Look, truth be told, the next week and a half is a bit of a struggle. We're looking at a lot of choppy, cross-shore conditions with small, weak swells. The wind's mostly out of the ENE and it's just not playing nice for the reef at Ammonias. The water temp is sitting at 80°F, which is about 0.7°F off average, so nothing unusual there. It's gonna be a waiting game for something worth paddling out for.
We kick off on Saturday the 22nd with a tiny 2ft SW groundswell, but with a 12 mph cross-on breeze, it's choppy and messy. That combo gives us a combined swell energy of 533, which is moderate but not doing much good. The rest of the week stays small and poor. There's a little spike in energy on the 27th with a 4ft S swell at a long 17 seconds, giving a combined energy of 884, but that cross wind just ruins it. This whole stretch through to the end of August is pretty much a write-off – mostly poor or marginal, with the wind keeping things ugly.
Now, let's talk about the bright spot. It's a long way off, but the weekend of the 6th and 7th of September is looking promising. On Sunday the 6th, we get a solid 8ft ENE swell with a 14-second period. That's a proper groundswell. The combined energy jumps to a very strong 2967. The wind is still cross-onshore, but only a gentle 9 mph, which is way better than what we've been seeing. This is going to be the standout period. That size is getting into the expert-only territory, so only charge if you've got the skills. But the better energy and those longer gaps between sets will make the paddle out a bit easier. It's a reef break too, which likes a longer period swell. Just remember the crowds at Ammonias can get heavy, so expect company.
Before that, the 5th of September also has a little buzz, with a 6ft ENE swell in the morning (combined energy 1004) and then a cleaner 4ft E swell in the afternoon with a 16-second period (combined energy 1296). The afternoon has a lighter wind, so that could be the pick of the day if you can't wait.
So, my call: suffer through the next 8-9 days of rubbish, then keep your eyes locked on September 6th and the days around it. That's where the good stuff is hiding.
Rusty.
Short Range ForecastLight rain (total 7mm), mostly falling on Mon morning. Warm (max 27°C on Sat morning, min 25°C on Sat night). Wind will be generally light. | Days 4-6 Weather SummaryLight rain (total 3mm), mostly falling on Tue morning. Warm (max 27°C on Tue afternoon, min 24°C on Wed night). Wind will be generally light. | ||||||||||||||||||||
Saturday 22 | Sunday 23 | Monday 24 | Tuesday 25 | Wednesday 26 | Thursday 27 | Friday 28 | |||||||||||||||
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) | SW 16 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | SSW 14 | ENE 6 | ENE 7 | E 7 | E 7 | ENE 7 | E 7 | SSW 14 | S 18 | S 19 | S 17 | S 17 | S 15 | S 14 | S 14 | S 14 |
Wave Graph | |||||||||||||||||||||
261 | 262 | 276 | 301 | 219 | 212 | 252 | 268 | 226 | 255 | 277 | 240 | 215 | 395 | 573 | 699 | 553 | 567 | 334 | 320 | 294 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | cross | cross | cross | cross | cross | cross | cross | cross | cross-on | cross | cross | cross | cross | cross | cross | cross | cross-on | cross-on | cross | cross |
High Tide | 1:07PM0.59m | 00:35AM0.22m | 1:46PM0.62m | 1:16AM0.25m | 2:19PM0.63m | 1:51AM0.28m | 2:48PM0.64m | 2:25AM0.31m | 3:14PM0.64m | 3:02AM0.35m | 3:38PM0.62m | 3:40AM0.38m | 4:02PM0.59m | 4:22AM0.42m | |||||||
Low Tide | 9:13PM0.18m | 5:45AM0.08m | 9:16PM0.18m | 6:37AM0.05m | 9:23PM0.17m | 7:21AM0.04m | 9:34PM0.16m | 8:01AM0.03m | 9:50PM0.13m | 8:40AM0.04m | 10:08PM0.11m | 9:19AM0.06m | 10:29PM0.08m | ||||||||
6:16 | — | — | 6:16 | — | — | 6:16 | — | — | 6:18 | — | — | 6:18 | — | — | 6:18 | — | — | 6:18 | — | — | |
— | 7:01 | — | — | 7:01 | — | — | 7:00 | — | — | 7:00 | — | — | 6:59 | — | — | 6:58 | — | — | 6:57 | — | |
mm | — | — | — | — | — | 1 | 3 | 1 | 2 | 1 | — | — | — | — | — | — | — | 2 | — | 1 | 1 |
Temp °C | 27 | 27 | 25 | 27 | 27 | 25 | 26 | 27 | 26 | 26 | 27 | 25 | 26 | 26 | 25 | 26 | 26 | 25 | 26 | 26 | 25 |
Feels °C | 28 | 28 | 26 | 28 | 27 | 25 | 26 | 28 | 27 | 27 | 28 | 26 | 26 | 25 | 25 | 26 | 25 | 26 | 26 | 25 | 24 |
Swell 1 Height (m) Direction Period (s) | SW 16 | SW 16 | SSW 16 | SSW 15 | SSW 15 | SSW 14 | SSW 14 | SSW 13 | SSW 12 | SSE 9 | SSE 9 | SSW 15 | SSW 14 | S 18 | S 19 | S 17 | S 17 | S 15 | S 14 | S 14 | S 14 |
261 | 251 | 212 | 196 | 188 | 183 | 163 | 156 | 121 | 53 | 54 | 167 | 215 | 395 | 573 | 699 | 553 | 567 | 334 | 320 | 294 | |
Swell 2 Height (m) Direction Period (s) | W 10 | W 10 | WNW 11 | S 13 | SE 10 | SE 11 | SE 10 | SE 9 | SE 8 | SSW 16 | SSW 16 | SSE 9 | SSE 8 | SSW 13 | SSW 13 | SSW 12 | S 12 | NNE 7 | SSW 11 | E 17 | E 16 |
74 | 56 | 98 | 130 | 59 | 44 | 58 | 36 | 48 | 201 | 193 | 54 | 45 | 133 | 135 | 79 | 73 | 11 | 40 | 145 | 248 | |
Swell 3 Height (m) Direction Period (s) | S 15 | SSE 15 | S 14 | SE 9 | E 9 | S 13 | S 14 | SSE 12 | SSW 16 | SSW 12 | SSW 12 | SSW 12 | S 18 | W 10 | W 10 | NNE 8 | NNE 8 | W 10 | E 18 | SSW 19 | SSW 19 |
109 | 73 | 107 | 49 | 25 | 89 | 101 | 28 | 153 | 83 | 85 | 79 | 167 | 8 | 7 | 13 | 13 | 8 | 98 | 36 | 70 | |
Wind waves Height (m) Direction Period (s) | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 6 | ENE 6 | ENE 7 | E 7 | E 7 | ENE 7 | E 7 | E 6 | E 7 | E 6 | E 6 | E 6 | E 6 | ENE 6 | ENE 6 | E 7 |
163 | 262 | 276 | 301 | 219 | 212 | 252 | 268 | 226 | 255 | 277 | 240 | 213 | 210 | 132 | 106 | 89 | 92 | 155 | 165 | 226 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 31 | 16 | 16 | 31 | 33 | 16 | 33 | 16 | 16 | 31 | 31 | 16 | 31 | 16 | 16 | 31 | 16 | 16 | 31 | 33 | 16 |
Best forecast wave conditions in Kaua'i | |||||||||||||||||||||
Best forecast wave conditions in United States | |||||||||||||||||||||
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Information about the Ammonias Surf forecast
The above surf forecast table for Ammonias provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Ammonias can be found by selecting the local surf guide option on the grey menu. Our Ammonias 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 (Ammonias) 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 Ammonias 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 vacation in Kaua'i? If you are looking for accommodation near Ammonias, camping, hotels and condos and appartments in Kaua'i, consider staying in Nawiliwili which is 2 km (1 miles) away. Alternatively, find information about places to stay and car hire in Lihue - Kauai which is 3 km (2 miles) away











