South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Thursday 27th August)

Best Days: Fri: strong S'ly groundswell easing across Northern NSW, with a small trade swell in SE Qld. Sat: new S'ly swell building across Northern NSW, with a small trade swell in SE Qld. Late Sun/Mon: strong S'ly swell in Northern NSW, may also see some fun waves in SE Qld. Tues thru' Thurs: plenty of SE swell. 

Recap: Small easterly swell has provided SE Qld with a few clean rideable waves in the last few days, whilst sideband SE swell from an East Coast low has generated good surf across northern NSW, biggest in the southern Mid North Coast region (closest to the swell source). Winds have been generally light and favourable. A new long period S’ly swell is showing strongly in Southern NSW today and should reach the Lower Mid North Coast this afternoon, and remaining coasts overnight.

Friday and this weekend (Aug 28 - 30)

The new southerly groundswell advancing across Southern NSW is producing some unreal waves. Most Sydney beaches are in the 3-5ft range and the Hunter region is seeing 5-6ft sets, so as a result I’ve slightly upgraded wave height estimates from this system on Friday to 3-5ft at south facing beaches in Northern NSW. 

Southern regions (south of Coffs) will see an overnight peak in size on Friday and an all-day easing trend, where as the Far North should see the peak of this swell hold into the afternoon. Locations not open to the south will be much smaller, and unfortunately this swell won’t do a lot north of the border; it’ll probably just mix in nicely with the small, pre-existing E’ly swell around 1-2ft+. However, if you can get yourself to an exposed south facing beach there should be occasional 3ft+ bombs across the Gold and Sunny Coasts.

Friday’s conditions look pretty good with mainly light variable winds across most regions. However the afternoons will be susceptible to moderate onshore flows due to this troughy, unstable pattern we’re in the midst of.

As for the weekend, we’re looking at similar winds - variable due to a trough pattern, with a southerly flow pushing into the Mid North region on Sunday, linked in with a broad, slow moving low pressure system in the Southern Tasman Sea. 

The weekend’s surf will originate from a couple of sources. We’ve got more E’ly trade swell on the cards, originating from distant activity way out NE of New Zealand earlier this week, but I can’t see there being much more than occasional 1-2ft+ waves at most open beaches. 

Otherwise, Saturday has a small building S’ly swell for exposed south facing beaches in Northern NSW, originating from a cut-off low that’s expected to form off the Southern NSW coast on Friday. It’ll only last a short time inside our swell window, and will do most of its work inside the Hunter shadow, so wave heights won’t be large and will be restricted to the swell magnets. However, we should see occasional 3ft+ sets at swell magnets through Saturday (with the Far North seeing a delay on the arrival of this swell, until late morning or lunchtime). Otherwise, expect a small mix of swells at remaining beaches.

Saturday’s south swell will then ease slowly into Sunday morning - still providing good waves at exposed beaches under a variable morning breeze. The Lower Mid North Coast should see a late arrival of stronger new S’ly groundswell, originating from the parent S’ly fetch contained within this broad system, that’s expected to develop south of the cut-off low, later Friday. This should be worth a few bigger sets in the 4-5ft range but most locations will have to wait until Monday to see it push through.

Next week (Aug 31 onwards)

The new S’ly swell due late Sunday or Monday looks like being a tricky bugger to forecast for. The source of this swell - a new low pressure system developing well south of the Tasman Sea (technically the Southern Ocean) on Friday - is a very unusual pattern, which exaggerates the difficulty in estimating surf size because I can't recall seeing a fetch track in this direction, in this region before. So there's no precedence to work against.

Additionally, the models have been moving around a lot with this synoptic setup in recent runs (shunting the fetch inside, and then outside of the swell window). It's quite likely that they'll continue to move around for the next few days so let's leave things until tomorrow when there should be more confidence. However at this early stage 4-6ft sets at south facing beaches in Northern NSW seems a reasonably good ball park figure for Monday, and there should be very good waves across the semi-exposed points too. 

SE Qld is hard to estimate from this source too as we haven’t see these kinds of systems before. Ordinarily, a south swell usually means wave height potential is significantly reduced but I think this system may buck the trend, and we may see some fun peelers across the outer points on Monday in the 2-3ft range. 

Looking further ahead, and this system looks like it’ll remain slow moving throughout the Southern Tasman Sea for quite a few days, meaning it’ll be a source of swell for the rest of the week in varying capacities. At this stage there’s enough confidence to estimate - as a minimum - moderate SE swell holding from Tuesday through Wednesday and maybe even Thursday, although the first half of the week will certainly see the most size. 

Further ahead, and another low is expected to develop off the South Coast of NSW mid-late next week which (1) has potential for a solid short range south swell but (2) may also deliver northerly winds during the aforementioned mid-week SE swells. So, make the most of what you see early in the week!

I’ll update this forecast on Friday afternoon.