Surf Forecasts:
Thirroul surf forecast from 16 Sep 2026:
- Best quality surf: Thursday 17 Sep, 7PM (local time) - 6ft (1.8m), 9s period, SSE swell with glassy winds.
- Most powerful swell: Thursday 17 Sep, 1AM (local time) - 11ft (3.5m), 11s period, SSE swell with 2,507 kJ wave energy.
- Next surfable swell (1★+): Thursday 17 Sep, 7PM (local time) - 6ft (1.8m), 9s period with SSE swell.
Best Forecast Surf Conditions for Thirroul this week:
The surf forecast for Thirroul over the next 16 days: The first swell (rated 1 star or higher) is forecast to arrive on Thursday (Sep 17) at 7PM. The primary swell is predicted to be 1.8m and 9s period with a secondary swell of 0.1m and 13s. The wind is predicted to be glassy as the swell arrives.
The most powerful waves expected at Thirroul in the next 16 days are 3.5m 11s and forecast to arrive on Thursday (Sep 17) at 1AM. Winds are predicted to be cross-shore at the time the swell arrives. The largest open ocean swell (not directed at the beach) is 0.6m 3s period and expected on Saturday (Sep 19) at 7PM.
| Wave Type | Time (AEST) & Date | Wave Height & Period |
|---|---|---|
| Next good surf (1 star+) | 7PM (Thu 17th Sep) | 6ft (1.8m) 9s |
| Best Surf | 7PM (Thu 17th Sep) | 6ft (1.8m) 9s |
| Most Powerful | 1AM (Thu 17th Sep) | 11ft (3.5m) 11s |
Table - best surf conditions forecast for Thirroul over the next 16 days.
The Lowdown
Alright, let’s get into it. The surf’s been all over the shop lately, and honestly, the start of this stretch ain’t flash. We’ve got a pulse of S swell pushing through, but it’s messy and lumpy. Wednesday arvo’s a write-off – 3.0m of south swell, but it’s cross-onshore and ugly. You’d be fighting it, not surfing it. Thursday’s not much better, still lumpy and cross. We’re looking at a couple of days of chop before things clean up.
Now, hold on. Friday morning the 18th is where it starts to turn. The swell drops back to 1.2m, but the wind goes glassy, and that’s a game changer. It’s a small, clean wave, but it’ll be worth a paddle. Saturday the 19th, the swell bottoms out – tiny – but there’s a fun little window early morning with clean conditions. Sunday the 20th has a long-period groundswell filling in from the SSE, 20 seconds. That’s proper energy for Thirroul (Big Island), and the morning’s clean with a cross-offshore wind. It’s not big, but it’ll be lined up and fun on the reef.
Monday the 21st still has some of that long-period SSE swell, but the morning’s clean, then the arvo gets blown out by a fresh SSE breeze. So you gotta get in early. Tuesday and Wednesday are pretty average, small and onshore – not worth the effort.
Then we hit a gap. The last couple of days of September are pretty grim. Tiny, weak, short-period ENE windswell with ordinary conditions. You’d be scratching. But then, hold onto your board – Thursday the 1st of October. That’s the standout. Clean, glassy morning, and we finally get a decent S swell at 2.0m with a 10-second period. The energy’s moderate-strong (951 combined energy) and the winds are glass. That’s the one to circle on the calendar. You’ll want to be at Thirroul early for the cleanest lines. The arvo’s still surfable but the NE sea breeze will put a bit of chop on it.
So, short story: there’s a couple of clean, small windows early on. But the real winner is that Thursday the 1st. Mark it down. Water temp’s around 18.1°, which is pretty much normal for this time of year.
Catch ya in the water.
Short Range ForecastMostly dry. Warm (max 28°C on Sat morning, min 9°C on Wed night). Winds decreasing (fresh winds from the S on Wed night, calm by Fri morning). | Days 5-7 Weather SummarySome drizzle, heaviest during Mon night. Warm (max 29°C on Mon morning, min 13°C on Mon night). Wind will be generally light. | ||||||||||||||||||
Thursday 17 | Friday 18 | Saturday 19 | Sunday 20 | Monday 21 | Tuesday 22 | ||||||||||||||
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) | SSE 11 | S 9 | SSE 9 | SSE 8 | S 9 | S 9 | S 9 | S 9 | S 9 | S 10 | SSE 19 | SSE 18 | S 11 | SSE 12 | SSE 6 | SSE 10 | SSE 11 | SSE 10 | SSE 19 |
Wave Graph  | |||||||||||||||||||
 kJ | 2507 | 1238 | 559 | 354 | 230 | 171 | 108 | 58 | 41 | 51 | 286 | 254 | 181 | 232 | 200 | 1155 | 202 | 370 | 210 |
Wind (km/h) | |||||||||||||||||||
Wind State on-shore cross-onshore cross-shore cross-offshore off-shore glassy | cross | cross | on | off | glassy | cross-on | cross-off | cross-off | cross-off | cross-off | cross-off | cross | off | cross-off | cross-on | cross-on | cross-on | on | glassy |
High Tide | 11:46PM0.98m | 12:02PM1.30m | 00:43AM0.90m | 12:58PM1.25m | 1:57AM0.85m | 2:06PM1.22m | 3:21AM0.85m | 3:17PM1.23m | 4:28AM0.90m | 4:18PM1.27m | 5:18AM0.97m | 5:08PM1.33m | |||||||
Low Tide | 5:23AM0.46m | 6:56PM0.43m | 6:08AM0.53m | 8:07PM0.47m | 7:08AM0.59m | 9:23PM0.47m | 8:26AM0.60m | 10:27PM0.42m | 9:42AM0.57m | 11:15PM0.36m | 10:42AM0.51m | 11:53PM0.29m | |||||||
 |  | |  | | | | | | | | | |  |  |  | | | | |
 | — | 5:54 | — | — | 5:52 | — | — | 5:50 | — | — | 5:50 | — | — | 5:48 | — | — | 5:47 | — | — |
 | — | — | 5:47 | — | — | 5:49 | — | — | 5:49 | — | — | 5:50 | — | — | 5:51 | — | — | 5:51 | — |
mm | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 1 | — | — | — |
Temp °C | 13 | 16 | 15 | 11 | 20 | 20 | 19 | 28 | 27 | 18 | 27 | 26 | 20 | 29 | 16 | 13 | 15 | 15 | 14 |
Feels °C | 5 | 12 | 12 | 9 | 17 | 18 | 14 | 25 | 22 | 14 | 25 | 25 | 18 | 24 | 11 | 9 | 12 | 12 | 13 |
Swell 1 Height (m) Direction Period (s) | E 13 | SSE 9 | SSE 9 | SSE 8 | S 9 | S 9 | S 9 | S 9 | S 9 | S 3 | S 8 | SSE 18 | S 11 | SSE 12 | NE 5 | S 18 | SSE 7 | SSE 10 | SSE 10 |
| kJ | 3 | 979 | 559 | 354 | 230 | 171 | 108 | 58 | 41 | 6 | 136 | 254 | 181 | 232 | 1 | 6 | 164 | 370 | 157 |
Swell 2 Height (m) Direction Period (s) | S 18 | E 13 | E 13 | E 13 | SE 7 | ESE 7 | SSE 17 | SSE 16 | SSE 18 | S 10 | SSE 19 | S 7 | SSE 17 | NE 4 | E 11 | S 22 | SSE 11 | SSE 19 | SSE 19 |
| kJ | 7 | 3 | 3 | 3 | 53 | 47 | 93 | 53 | 30 | 51 | 286 | 52 | 59 | 3 | 2 | 9 | 202 | 35 | 210 |
Swell 3 Height (m) Direction Period (s) | — | NE 13 | S 19 | S 19 | SSE 18 | SSE 17 | SE 7 | SE 7 | ESE 7 | SSE 18 | E 11 | S 11 | NE 4 | E 11 | E 11 | — | S 20 | S 15 | S 13 |
| kJ | — | 7 | 7 | 7 | 32 | 59 | 13 | 8 | 5 | 33 | 2 | 93 | 4 | 3 | 2 | — | 8 | 4 | 14 |
Wind waves Height (m) Direction Period (s) | SSE 11 | S 9 | — | — | — | NE 3 | W 3 | W 3 | W 2 | — | NNW 2 | ENE 4 | — | — | SSE 6 | SSE 10 | — | — | E 6 |
| kJ | 2507 | 1238 | — | — | — | 4 | 1 | 1 | 1 | — | 1 | 12 | — | — | 200 | 1155 | — | — | 103 |
Nearest Offshore or Glassy | |||||||||||||||||||
Distance (km) | 658 | 39 | 37 | 79 | 0 | 0 | 6 | 2 | 2 | 2 | 0 | 0 | 2 | 0 | 0 | 328 | 86 | 27 | 5 |
Best forecast wave conditions in Illawarra | |||||||||||||||||||
Best forecast wave conditions in Australia | |||||||||||||||||||
Header Global | |||||||||||||||||||
- Map Icons:
Break
Live Wave Height (m)
Live Wind Speed (km/h)
Surf Rating (10 Max)
Ocean Swells (m)- Wind Speed (km/h)
FREE! Surf-Forecast.com widget for your website
The surf report / weather widget below is available to embed on third party websites free of charge and provides a summary of our Thirroul surf forecast. Simply grab the html code snippet that we provide and paste it into your own site. You can choose your preferred language and metric/imperial units for the surf forecast feed to suit users of your site. Click here to get the code.
Information about the Thirroul Surf forecast
The above surf forecast table for Thirroul provides essential information for determining whether the surfing conditions will be good over the next 16 days. A general guide to surfing at Thirroul can be found by selecting the local surf guide option on the grey menu. Our Thirroul 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 (Thirroul) 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 Thirroul 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 Illawarra? If you are looking for accommodation near Thirroul, camping, hotels and holiday cottages in Illawarra, consider staying in Wollongong which is 12 km (7 miles) away. Other places in and around Illawarra where you can find information about places to rent, and car hire include Port Kembla which is 19 km (12 miles) away, Engadine, Cronulla and Caringbah.
Nearest