Wide range of swell sources on tap

Ben Matson picture
Ben Matson (thermalben)

Southeast Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Monday 4th August)

Best Days: SE Qld: peaky swell combo Tues/Wed, best suited to the semi-exposed points. Northern NSW: good quality south swell Thurs/Fri/Sat/Sun with generally light winds. 

Recap: Small waves on Saturday in most areas ahead of a building south swell across Northern NSW that was decimated by onshore winds. Sunday saw plenty of south swell across Northern NSW but protected locations were only small and SE Qld didn’t pull in much size at all. Today has seen a combo of easing S’ly swell across south facing beaches in Northern NSW, and a building short range SE swell across the southern Queensland coast (biggest on the Sunny Coast). A small long range E’ly swell was also expected to arrive this afternoon, however I’m unsure whether it’s actually reached the coast yet. Swell directions at the Tweed, Gold Coast and Brisbane buoys have also swung E’ly however spectral data from Byron shows a predominant SE direction (and surfcam obs show very small waves on the southern Gold Coast points, whilst D’Bah is a good 2-3ft - suggesting there’s more south than east in the water right now).

This week (Aug 5-8)

We’ve got several sources of new swell for the coming week. First up, the ridge through the southern Coral Sea will continue to supply small short range SE swell to the southern Qld coast for the next few days. The Sunshine Coast will pick up the most size from this source (2-3ft+ sets at open beaches), with slightly smaller waves on the Goldy and subsequently down the North Coast. However mainly fresh SE winds (save a brief period of early SW winds in a few selected areas) will confine the best waves to the semi-exposed points.

Also in the water on Tuesday and Wednesday will be a small east swell generated by a modest belt of near-stationary E’ly winds way out east of Fijian longitudes over the weekend. No great size is expected from this source - it’ll mainly mix in with the pre-existing SE swell in Queensland - however it’ll provide a few peaky options along the North and Mid North Coasts (albeit a little smaller in size than up north). Local winds will be lighter south of about Yamba, and the early morning sou’wester will probably linger longer. So there should be some fun small beachies about the place.

Otherwise, the dominant theme for the week - exclusive to Northern NSW - is for a series of pulsey south swells. We’ve had plenty of southerly energy over the last few days and there’s a couple of solid new swells expected throughout the forecast period, all courtesy of a vigorous storm track well south of the continent.

Tuesday's late arrival of new south swell will appear most prominently in the water on Wednesday morning, with most of Northern NSW’s south facing beaches seeing inconsistent 2-3ft waves (in and amongst the other swell trains).

However, a second, stronger and even longer period south swell will then push through the lower Mid North on Wednesday morning, reaching the North Coast during the middle of the afternoon. This swell will have been generated by a very powerful low tracking below Tasmania this evening (see below). Although wind speeds are expected to reach 50-60kts around the low's core, it will be tracking quickly east through our swell window and the unfavourable alignment of the storm track will cap wave heights along the East Coast.

South facing beaches should see occasional 3-4ft sets at times, although it will be very inconsistent, and it'll be smaller at beaches not open to the south. Conditions should be good in most areas with light variable winds tending onshore during the day (possibly moderate to fresh SE in the north).

Thursday is a difficult call. I’m expecting all swell sources to have eased back a touch by this time, however our automated model is calling for 3ft E’ly swell in SE Qld, which I really can’t pin down the source of.

The current fetch just east of Fiji is expected to have exhausted its energy at the coast by this time, and although there’s another decent looking fetch much further to the east at the moment (S/SE of Tahiti), I really think that it’s too far away to generate anything meaningful for the coast (and probably wouldn't arrive until the weekend anyway). Our model also has smaller surf in Northern NSW at this time (i.e. 2ft E’ly swell in Yamba), which doesn’t add up either as all locations should see a similar size coverage of east swell from either of these sources.

So I’m, going to put it down to a model aberration and call in my expectations for a peaky mix of swells in and around the 2ft mark at most exposed beaches on Thursday (maybe some bigger leftover sets from the south early morning, near 3ft at south facing beaches in Northern NSW).

Friday will then see a continuation of Thursday’s overall easing trend, with generally light winds. 

This weekend (Aug 9-10)

The weekend’s looking pretty good for Northern NSW. A new long period southerly groundswell is expected to push into the region overnight on Friday, and this is expected to produce solid waves at south facing beaches in the 3-5ft range on Saturday. Conditions are looking pretty good with generally light winds. However, it’ll be smaller at beaches not completely open to the south.

SE Qld will see much smaller surf away from the south swell magnets - most locations are looking at a peaky mix of residual E’ly trade swell (from a ridge in the central/northern Coral Sea, mainly outside out swell window) and some refracted southerly groundswell - perhaps sets in there 2ft range at best.

The southerly swell will then ease through Sunday with mainly light winds in all regions. So, aim for Saturday for the biggest and best waves in Northern NSW. 

Longer term (Aug 11 onwards)

This recent pattern of regular south swells looks set to continue through much of next week, with no major disruption expected to the the South Ocean storm track. And although not especially strong, we’re likely to see a continuation of very small E’ly swell about the SE Qld coast next week thanks to a weak trade flow across the broader swell window. More on this in Wednesday’s notes.