
Surf Forecasts:
Ammonias surf forecast from 9 Jul 2026:
- Most powerful swell: Thursday 9 Jul, 8AM (local time) - 8ft (2.4m), 8s period, ENE swell with 707 kJ wave energy.
Best Forecast Surf Conditions for Ammonias this week:
The most powerful waves expected at Ammonias in the next 16 days are 2.4m 8s and forecast to arrive on Thursday (Jul 09) at 8AM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.8m 15s period and expected on Wednesday (Jul 15) at 2AM.
| Wave Type | Time (HST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | - | - |
| Best Surf | - | - |
| Most Powerful | 8AM (Thu 9th Jul) | 8ft (2.4m) 8s |
Table - best surf conditions forecast for Ammonias over the next 16 days.
Alright, folks, Rusty here. Let’s break down what’s happening at Ammonias for the next couple weeks.
Honestly, this is a rough one. For the first ten days or so, the wind is a total buzzkill. A persistent moderate cross-onshore or cross-shore breeze from the east-northeast, blowing 12 to 19 mph, is keeping the surface lumpy and choppy. The swell is running between 6 ft and 7 ft for most of that time, but it’s wind-affected, short-period junk (7 to 8 seconds), and the combination of onshore wind and short period means the waves are just messy. The combined swell energy is moderate, ranging from 464 to 996 (moderate wave energy), but it’s all pretty unappealing. You’re looking at poor surf conditions straight through from Thursday, July 9, into the middle of the following week.
Then, around Monday, July 20, we see a glimmer. The wind eases a touch to 12 mph, and the swell period starts to stretch out. By Tuesday, July 21, we get a real change: a long-period groundswell rolls in from the east with a period of 17 seconds, though the swell height drops to 4 ft to 4 ft. The combined energy jumps up to 1212 and 1499 (strong to very strong wave energy), which is impressive for the size. But here’s the catch – the wind is still cross-shore and moderate, and the swell direction (E) isn’t a perfect match for Ammonias’ optimum swell direction (SSE). The long period is great for shape and energy, but at a reef break, a straight east swell can sometimes be a bit tricky. It’s still a marginal call, but it’s the closest thing to a standout in the whole run. The water temperature is about average for the time of year, so no drama there.
The standout for the whole outlook is that Tuesday, July 21. If you can get out on that morning, you’ll find a 4 ft, 17-second groundswell with moderate cross-shore wind. The crowd profile at Ammonias is "often" busy, so expect some company. For a reef break, it’s a solid option, but the conditions are still marginal, so don’t expect perfection.
After that, the swell fades and the wind remains onshore, turning the last few days into a pretty poor run again. The second week is a real mixed bag of low energy and poor conditions, so don’t hold your breath for a clean session.
Overall, it’s a disappointing forecast. The first ten days are a write-off due to onshore wind and short-period chop, and the only real promise is that Tuesday, July 21, which offers a taste of groundswell but still has cross-shore wind. For a spot that’s fairly consistent, this is a rare blank run. The best advice is to watch that Tuesday window closely, but don’t get your hopes up too high.
Rusty.
Short Range ForecastModerate rain (total 12mm), heaviest on Wed night. Warm (max 25°C on Thu morning, min 24°C on Wed night). Mainly fresh winds. | Days 5-7 Weather SummaryModerate rain (total 15mm), heaviest on Sun night. Warm (max 26°C on Tue afternoon, min 23°C on Sat night). Wind will be generally light. | ||||||||||||||||||||
Thursday 9 | Friday 10 | Saturday 11 | Sunday 12 | Monday 13 | Tuesday 14 | Wed 15 | |||||||||||||||
Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | Night | AM | PM | |
Swell Height Map | |||||||||||||||||||||
Wave Height (m) Direction Period (s) | ENE 8 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | SSW 17 | ENE 7 | ENE 8 | ENE 8 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 |
Wave Graph | |||||||||||||||||||||
672 | 584 | 509 | 428 | 366 | 334 | 346 | 456 | 417 | 386 | 475 | 581 | 607 | 463 | 362 | 337 | 340 | 319 | 327 | 330 | 281 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | cross-on | cross-on | cross | cross | cross | cross | cross | cross | cross | cross-on | cross | cross | cross | cross | cross | cross | cross | cross-on | cross-on | cross-on |
High Tide | 8:28PM0.28m | 12:45PM0.59m | 9:34PM0.22m | 1:33PM0.67m | 11:46PM0.18m | 2:19PM0.73m | 1:06AM0.18m | 3:04PM0.77m | 2:08AM0.19m | 3:47PM0.78m | 3:04AM0.21m | 4:29PM0.77m | 3:58AM0.23m | 5:08PM0.73m | |||||||
Low Tide | 4:28AM-0.03m | 9:16PM0.22m | 5:17AM-0.06m | 9:34PM0.17m | 6:09AM-0.08m | 10:03PM0.14m | 7:03AM-0.10m | 10:34PM0.12m | 7:55AM-0.11m | 11:06PM0.11m | 8:46AM-0.10m | 11:38PM0.10m | 9:34AM-0.07m | ||||||||
— | 6:00 | — | — | 6:00 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | — | 6:01 | — | |
7:23 | — | 7:23 | — | — | 7:23 | — | — | 7:23 | — | — | 7:23 | — | — | 7:23 | — | — | 7:22 | — | — | 7:22 | |
mm | 4 | 4 | 2 | 2 | — | — | — | — | — | — | 2 | 2 | 5 | 1 | — | 4 | — | 1 | 5 | 2 | — |
Temp °C | 24 | 25 | 25 | 24 | 25 | 25 | 24 | 24 | 25 | 24 | 25 | 25 | 24 | 25 | 25 | 24 | 25 | 26 | 24 | 26 | 26 |
Feels °C | 22 | 24 | 24 | 23 | 24 | 23 | 23 | 22 | 23 | 23 | 24 | 23 | 23 | 24 | 24 | 23 | 24 | 26 | 23 | 26 | 25 |
Swell 1 Height (m) Direction Period (s) | S 13 | S 12 | S 12 | S 12 | S 12 | S 11 | SW 19 | SSW 18 | SW 18 | SSW 17 | SSW 16 | SSW 16 | SW 16 | SSW 15 | SSW 14 | SW 14 | SW 14 | SW 14 | W 15 | W 15 | W 15 |
168 | 151 | 108 | 106 | 98 | 66 | 184 | 214 | 316 | 386 | 326 | 322 | 353 | 279 | 268 | 206 | 189 | 186 | 302 | 283 | 275 | |
Swell 2 Height (m) Direction Period (s) | SE 8 | SE 8 | SE 8 | SE 6 | W 13 | W 13 | S 11 | S 12 | SE 9 | S 13 | SSE 12 | SSE 12 | SSE 12 | W 19 | SSE 11 | W 17 | W 16 | W 16 | SSW 13 | SW 13 | SSW 12 |
11 | 11 | 11 | 10 | 28 | 55 | 60 | 44 | 26 | 51 | 50 | 49 | 48 | 112 | 84 | 140 | 257 | 248 | 109 | 162 | 104 | |
Swell 3 Height (m) Direction Period (s) | W 15 | W 14 | W 14 | W 13 | W 15 | SE 8 | W 14 | W 14 | S 12 | SE 9 | W 12 | W 12 | W 12 | SSE 12 | W 18 | SSE 11 | SSW 19 | SE 6 | SSW 17 | SSW 18 | SSW 15 |
17 | 15 | 32 | 30 | 38 | 17 | 58 | 61 | 44 | 28 | 26 | 26 | 26 | 47 | 150 | 40 | 146 | 10 | 200 | 123 | 87 | |
Wind waves Height (m) Direction Period (s) | ENE 8 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 8 | ENE 8 | ENE 8 | ENE 8 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 | ENE 7 |
672 | 584 | 509 | 428 | 366 | 334 | 346 | 456 | 417 | 352 | 475 | 581 | 607 | 463 | 362 | 337 | 340 | 319 | 327 | 330 | 281 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 38 | 38 | 126 | 16 | 33 | 31 | 31 | 33 | 33 | 16 | 31 | 31 | 38 | 33 | 31 | 16 | 31 | 16 | 16 | 33 | 31 |
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











