South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Monday 10th August)

Best Days: Tues: get in early before the south swell disappears. Northern corners only (mainly Northern NSW). Wed: chance for a late NW wind change, and a peaky NE windswell. Thurs: chance for some fun clean peaky NE windswell in SE Qld (smaller in Northern NSW south of Byron). Fri/Sat/Sun: small clean waves at south facing beaches. Next week (prob Tues-Thurs): strong southerly groundswell across exposed beaches in Northern NSW.

Recap: The weekend delivered excellent waves across most regions. Saturday’s easing south swell (from Friday) ended up being bigger than forecast in Northern NSW; the easing trend didn’t really bottom out quite as much as I expected, with surf size remaining very similar to Friday. Sunday’s new pulse however delivered a sterling day of waves just about everywhere; even SE Qld pulled in a little more size than anticipated with solid 3ft+ sets at the outer points (as per the video here) and bigger waves at south swell magnets. Today we’ve seen surf size slowly abate but wave heights were still performing better than forecast, with the easing trend developing more slowly than anticipated. However, freshening northerly winds have ruined the surf at many spots from mid-morning onwards. 

This week (August 11 - 14)

So, right now we’re on the backside of the weekend’s south swell.

As wave heights continue to fade, Tuesday morning will see the most size, but estimating just how much is a little difficult as surf has been performing slightly above model expectations today. This doesn’t necessarily mean that tomorrow will perform the same - swell phases are nonlinear - so it could very well become very smaller, much more quickly than expected. 

Still, based on what we’ve seen in Southern NSW today, south facing beaches in Northern NSW should see 3ft sets early Tuesday, becoming smaller into the afternoon. Wave heights will be smaller at locations not completely open to the south. However, northern corners will offer the only rideable conditions as winds are expected to remain from the N/NW. 

In SE Qld, we’re looking at very small leftover south swell, and probably some local windswell in the mix too. Winds should be offshore NW across the beaches early morning but northerly tendency is expected to develop throughout the day. On the balance, not a great day for most of the Gold and Sunshine Coasts.

With the south swell likely to be all but gone by Wednesday, we’ll probably be relying on northerly windswell for our mid-week surf potential (see chart below). The airstream off the SE Qld Coast (between Fraser Island and Cooly) is expected to reach 25kts+ and this has the potential to generate 3ft+ peaky surf at exposed NE facing beaches by the afternoon. 

Unfortunately, Wednesday looks like a write-off as the accompanying northerly winds will be quite gusty however a fresh W/SW change is due overnight, and this has some promise for Thursday morning. Ideally, this change would push through in the early hours of the morning - allowing a couple of hours for the surf to clean up before wave heights start to drop - so I’m concerned that its current modelled arrival time (mid-late evening) may be too early - i.e. that wave heights may begin to ease well before the sun comes up.

But for now, let’s pencil in the possibility for some fun peaky offshore peaks across the open beaches on Thursday morning, in the 2ft+ range. If the change is delayed a little bit, and as long as the N’ly fetch remains in place, this could be upgraded. But I’ll have a better idea on Wednesday. NE windswells are not a regular occurrence in SE Qld and they’re a bucketload of fun across the beachies when they eventuate, so fingers crossed.

As for the Northern NSW coast south of Byron Bay, this northerly fetch looks less favourably positioned so we’re looking at the same overall pattern but with less size than in SE Qld, because the swell will have to refract further back into the coast (and will consequently lose size as it does so). The Tweed Coast is probably in the best position of all as it’ll pick up this swell quite well. We may also see winds swing NW later Wednesday across the Mid North Coast, so there’s a chance that some locations in Northern NSW may have some fun peaky waves late in the day on Wednesday. I’m not 100% on this but will update in the comments below as more information becomes available.

The strong winds mid-week will be related to the passage of several cold fronts across the eastern states, all of which will be riding quite north in latitude. Early Thursday morning, the Long Wave Trough will push off the East Coast, and this will allow the trailing winds behind the next front(s) to tend more SW in alignment, meaning they’ll be in a better position to generate swell from the southern quadrant.

In fact, we’ll see two fronts simultaneously develop inside our southern swell window - one off the Far Southern NSW Coast, and another just SE of Tasmania. The South Coast front will generate a short range swell for late Thursday afternoon (mainly the Mid North Coast) while the Tasmanian front will generate a slightly better south swell for late Friday and into Saturday.

Estimating wave heights from these systems is a little hard. Winds don’t look especially strong within the fronts and they’re poorly aligned, and not expected to hang around for very long either. At this stage south facing beaches in Northern NSW should see somewhere in the 3ft+ range, with smaller surf elsewhere. Don’t expect much energy to reach Far Northern NSW until Friday, and even then it’ll be pretty lacklustre.

So, getting an idea on Friday’s surf potential is hard as it’s likely we’ll probably be between south swells (the NE windswell will be all but gone by this time). The good news is that winds will be favourably light so we can expect - as a minimum - fun clean beach breaks across Northern NSW. However, surf size will probably be very small throughout SE Qld at this time, just a few small waves at south facing beaches.

 This weekend (Aug 15 - 16)

Nothing major on the cards for the weekend at this stage.

Friday’s south swell will ease slowly through Saturday, and as for new swell sources - a couple of weak fronts will nudge the lower Tasman Sea, and probably push up some small energy for exposed beaches in Northern NSW, but nothing to break the bank.

It’ll probably just be enough to keep the open beaches from becoming flat; at this stage a round figure in the 2ft range at south facing beaches both days (perhaps a little bigger on Saturday) seems about right, with smaller waves elsewhere. Winds should be light too under the influence of a broad ridge of high pressure.

As for SE Qld, a new ridge building through the Coral Sea looks like it’ll be positioned too far north to benefit SE Qld, so apart from a few small waves at south facing beaches, most beaches will probably be tiny. Let’s check back Wednesday to see if things have changed.

Next week (Aug 17 onwards)

The models are suggesting we’ll see a moderate ridge through the Northern Tasman Sea from Sunday onwards, which may whip up a minor trade swell for the first half of next week (no major size is expected though).

Elsewhere, a series of powerful Southern Ocean fronts/lows are expected to track under Tasmania starting next weekend, and will generate some excellent long period southerly groundswell for the Northern NSW coast next week (such swells rarely benefit SE Qld).

I’m a little concerned that the storm track will be quite zonal to begin with, which will probably shave a lot of size off the surf potential however by the first few days of next week, strong secondary fronts tracking behind should start to push through the swell window with a better orientation, which should generate some really good surf for the middle to latter part of the week.

At this stage it’s too early to pin down the specifics, so without wanting to be blasé about next week’s surf prospects I’d casually pencil out Tuesday to Thursday next week and start planning for some solid clean waves at south facing locations. More on this in Wednesday’s update.