Surf Forecasts:
Sponge bay surf forecast from 15 Aug 2026:
- Best quality surf: Thursday 20 Aug, 9AM (local time) - 10ft (3.0m), 13s period, SSW swell with cross-onshore winds.
- Most powerful swell: Tuesday 18 Aug, 9PM (local time) - 16ft (5.0m), 11s period, S swell with 6,651 kJ wave energy.
- Next surfable swell (1★+): Thursday 20 Aug, 9AM (local time) - 10ft (3.0m), 13s period with SSW swell.
Best Forecast Surf Conditions for Sponge bay this week:
The surf forecast for Sponge bay over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Thursday (Aug 20) at 9AM. The primary swell is predicted to be 3.0m and 13s period with a secondary swell of 1.6m and 10s. Another secondary swell of 1.2m and 13s is also forecast. The wind is predicted to be cross-onshore as the swell arrives.
The most powerful waves expected at Sponge bay in the next 16 days are 5.0m 11s and forecast to arrive on Tuesday (Aug 18) at 9PM. Winds are predicted to be cross-onshore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.4m 2s period and expected on Friday (Aug 21) at 9PM.
| Wave Type | Time (NZST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 9AM (Thu 20th Aug) | 10ft (3.0m) 13s |
| Best Surf | 9AM (Thu 20th Aug) | 10ft (3.0m) 13s |
| Most Powerful | 9PM (Tue 18th Aug) | 16ft (5.0m) 11s |
Table - best surf conditions forecast for Sponge bay over the next 16 days.
The Lowdown
Alright, Rusty here. Let’s have a look at what’s on the cards for Sponge Bay.
Honestly, the next week and a half is pretty grim. There’s a lot of swell but the wind is just wrecking it, and when the wind does ease off, the swell disappears. The water temperature is sitting at 55°, which is a bit colder than normal for this time of year, so that’s a bit of a buzzkill for the first session you might consider.
It kicks off with some buzz on Sunday the 16th, but don’t get excited. Sponge Bay is a beach and reef setup, and while there’s a 4ft swell from the east with a short period of 8 seconds, the wind is a fresh cross-onshore, making it lumpy and poor. The combined energy is only moderate (439), so nothing to write home about.
Sunday afternoon and all of Monday (the 17th) through to Wednesday (the 19th) are a write-off. The swell builds to 12ft and even 15ft, but strong to near-gale onshore winds from the south and southwest are going to make it a dangerous, messy washing machine. The combined energy hits very strong levels (up to 8355), but that’s just for the kite surfers – not for paddle surfing.
Thursday morning the 20th is the first real standout. The wind drops to a moderate cross-onshore from the WSW (12 mph), and you’ve got a solid 10ft swell from the SSW with a nice 13-second period. The energy is still very strong (3859). The comment says wind and tide are favorable, but the swell is too big for this break. That’s expert territory only; beginners should stay well clear. The swell direction from the SSW is a reasonable match for the optimum (SSE), but at that size, it’s going to be heavy.
After that, things mellow out. Friday the 21st and Saturday the 22nd see tiny waves (2ft to 3ft) but the wind finally turns good. Friday morning has a light cross-offshore from the NW, giving you clean 3ft waves from the ESE (period 8 seconds, energy weak at 239). Then Saturday afternoon the 22nd is glassy – a light easterly 3 mph – with a knee-high 2ft SSE swell, clean and surfable but very ordinary. The period jumps to 16 seconds on the Friday afternoon, but it’s tiny.
There’s then a gap from Sunday the 23rd through to Tuesday the 25th, with surf dropping to 0.5ft to 2ft. Not worth paddling out for unless you’ve got a longboard and no expectations.
The next real shot is Wednesday morning the 26th. Now this is the best of the whole 16 days. You’ve got 5ft of swell from the south, period only 8 seconds, but the wind is a gentle offshore from the NNW at 9 mph, making for clean conditions. The combined energy is moderate (454). It’s a proper, surfable, clean wave. This is the one to circle on your calendar.
After that, Thursday the 27th and Friday the 28th get messy again with strong cross-onshore winds and poor conditions, before a final marginal window on Saturday the 29th. That day shows a 5ft south swell with a short 6-second period, clean conditions but only a moderate rating.
So, if I had to pick the standout, it’s Wednesday the 26th August, early morning. Clean offshore wind, chest-to-head-high swell from the south. Nothing huge, but it’ll be the best quality you’ll see in this whole two-week stretch.
Stay patient, keep an eye on the forecasts, because when it goes clean, Sponge Bay can be fun.
Rusty.
Short Range ForecastHeavy rain (total 34mm), heaviest during Sun afternoon. Very mild (max 12°C on Sun morning, min 7°C on Mon night). Winds increasing (moderate winds from the SW on Sun morning, near gales from the SSW by Tue night). | Days 4-6 Weather SummaryLight rain (total 8mm), mostly falling on Wed night. Very mild (max 14°C on Fri morning, min 8°C on Thu night). Winds decreasing (strong winds from the SSW on Wed morning, calm by Fri morning). | ||||||||||||||||||||
Sunday 16 | Monday 17 | Tuesday 18 | Wednesday 19 | Thursday 20 | Friday 21 | Saturday 22 | |||||||||||||||
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) | E 8 | SSW 16 | SSE 10 | SSE 10 | S 10 | S 9 | S 9 | SSE 10 | SSE 12 | SSE 12 | S 12 | S 14 | SSW 13 | SE 9 | ESE 8 | ESE 8 | SSE 11 | SSE 15 | SSE 13 | SSE 12 | SSE 12 |
Wave Graph | |||||||||||||||||||||
205 | 229 | 1088 | 1249 | 2375 | 1655 | 1283 | 1461 | 3754 | 3797 | 5345 | 3857 | 2809 | 396 | 126 | 90 | 214 | 485 | 195 | 115 | 123 | |
Wind (km/h) | |||||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross-on | on | on | on | on | cross-on | cross-on | cross-on | cross-on | on | on | cross-on | cross-on | on | cross-off | cross-off | cross | cross-off | cross-off | glassy | cross-off |
High Tide | 8:51PM2.10m | 9:16AM2.02m | 9:37PM2.07m | 10:02AM2.01m | 10:22PM2.02m | 10:47AM1.96m | 11:06PM1.95m | 11:32AM1.90m | 11:48PM1.87m | 12:17PM1.84m | 00:30AM1.79m | 1:01PM1.78m | 1:14AM1.71m | ||||||||
Low Tide | 2:37PM0.43m | 3:10AM0.46m | 3:25PM0.47m | 3:54AM0.48m | 4:11PM0.52m | 4:39AM0.51m | 4:56PM0.58m | 5:24AM0.56m | 5:42PM0.65m | 6:09AM0.62m | 6:28PM0.72m | 6:53AM0.69m | 7:17PM0.77m | ||||||||
6:52 | — | — | 6:52 | — | — | 6:50 | — | — | 6:48 | — | — | 6:48 | — | — | 6:46 | — | — | 6:45 | — | — | |
— | 5:30 | — | — | 5:31 | — | — | 5:32 | — | — | 5:34 | — | — | 5:34 | — | — | 5:35 | — | — | 5:36 | — | |
mm | — | 9 | 7 | 2 | 1 | 3 | — | 5 | 7 | 1 | 1 | 6 | — | — | — | — | — | — | — | — | — |
Temp °C | 12 | 11 | 10 | 9 | 9 | 9 | 10 | 9 | 8 | 9 | 10 | 10 | 12 | 12 | 10 | 14 | 13 | 12 | 14 | 15 | 12 |
Feels °C | 7 | 4 | 1 | -1 | 0 | 0 | 0 | -2 | -3 | -2 | 1 | 3 | 6 | 7 | 7 | 12 | 11 | 8 | 12 | 13 | 8 |
Swell 1 Height (m) Direction Period (s) | E 8 | E 9 | ESE 9 | ESE 9 | SE 9 | SE 9 | SSE 9 | E 18 | — | — | SSE 12 | SSE 14 | SE 10 | SE 9 | ESE 8 | ESE 8 | SSE 11 | SSE 15 | SSE 13 | SSE 12 | SSE 12 |
205 | 194 | 343 | 265 | 1033 | 844 | 623 | 6 | — | — | 3010 | 2803 | 499 | 396 | 126 | 90 | 173 | 485 | 195 | 115 | 123 | |
Swell 2 Height (m) Direction Period (s) | S 5 | SSE 16 | S 19 | S 17 | ESE 10 | SSE 15 | SSE 14 | — | — | — | — | — | SSE 13 | SSE 13 | SSE 8 | SSE 9 | SSE 16 | ESE 10 | SE 10 | SE 10 | ESE 13 |
41 | 87 | 66 | 142 | 106 | 72 | 40 | — | — | — | — | — | 482 | 170 | 96 | 79 | 214 | 63 | 48 | 24 | 16 | |
Swell 3 Height (m) Direction Period (s) | SSE 18 | SSW 16 | SE 15 | — | S 16 | — | E 9 | — | — | — | — | — | SE 12 | E 13 | SSE 12 | SSE 11 | ESE 8 | — | SE 10 | SE 14 | ESE 9 |
103 | 229 | 9 | — | 126 | — | 26 | — | — | — | — | — | 69 | 3 | 46 | 70 | 45 | — | 45 | 8 | 8 | |
Wind waves Height (m) Direction Period (s) | SSW 5 | S 6 | SSE 10 | SSE 10 | S 10 | S 9 | S 9 | SSE 10 | SSE 12 | SSE 12 | S 12 | S 14 | SSW 13 | — | — | NNW 2 | — | NW 3 | W 4 | — | N 3 |
90 | 72 | 1088 | 1249 | 2375 | 1655 | 1283 | 1461 | 3754 | 3797 | 5345 | 3857 | 2809 | — | — | 1 | — | 2 | 2 | — | 1 | |
Nearest Offshore or Glassy | |||||||||||||||||||||
Distance (km) | 68 | 68 | 118 | 121 | 121 | 68 | 118 | 125 | 125 | 121 | 132 | 53 | 42 | 43 | 0 | 0 | 1 | 3 | 3 | 0 | 3 |
Best forecast wave conditions in Gisborne and Mahia | |||||||||||||||||||||
Best forecast wave conditions in New Zealand | |||||||||||||||||||||
Header Global | |||||||||||||||||||||
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Information about the Sponge bay Surf forecast
The above surf forecast table for Sponge bay provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Sponge bay can be found by selecting the local surf guide option on the grey menu. Our Sponge bay 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 (Sponge bay) 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 Sponge bay 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 Gisborne and Mahia? If you are looking for accommodation near Sponge bay, camping, hotels and holiday cottages in Gisborne and Mahia, consider staying in Gisborne which is 8 km (5 miles) away.











