South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Wednesday 30th December)

Best Days: Most days should have great waves though Thurs/Fri will remain wind affected. Sat/Sun should see large clean E/SE swells with excellent options right along the coast. Lots of sizeable options for next week too.

Recap: Strong S/SE swells across the region, limiting wave heights in SE Qld due to the southerly component in the direction but with gusty S’ly winds the points have been the best options. Surf size has been much bigger south of the border but strong local winds at times have presented issues at all but the most protected spots. 

This week (December 31st - January 1st)

We have a renewal of S/SE energy pushing up the coast today thanks to a small low that developed within the trough line extending the length of the Tasman Sea, on Tuesday. This low is now moving north, working on the pre-existing active sea state generated by the current fetch, which is essentially a strong ridge occupying the SE Qld and Northern NSW region.

Essentially, the resulting swell will build through Thursday and then ease on Friday. At its peak, we should see a little more size than what’s been offer over the last few days, though the strong southerly component will continue to restrict wave heights in and around the SE Qld region (away from south swell magnets, which will be wind affected anyway). 

As a rough guide, exposed spots in Northern NSW should see 5-6ft+ sets at times (probably peaking Thursday afternoon), with smaller waves at the semi-exposed points, and much smaller surf at protected points.

Across SE Qld, the outer points are likely to peak somewhere between 3ft and 4ft (smaller either side of this) on Thursday afternoon, however keep in mind that surf size will drop off as you work your way down the points. Most open beaches will probably be a foot or so under this, and the inner points/sheltered locations will be considerably smaller again. 

As this low pushes north it’ll also squeeze the isobars across the region too, so we can expect a continuation of these gusty SW/SE conditions for the next few days. 

In addition to a slow easing trend on Friday, we'll also have a large secondary swell on the approach too. As mentioned comprehensively in Monday’s notes, a large low pressure gyre across the Tropical South-western Pacific Ocean is generating several new easterly swell sources for the Australian East Coast. The first is expected to spin up south-east of New Caledonia today, with easterly gales feeding into the trough line across the Tasman Sea. 

This is expected to consolidate into a broad low pressure system across the Northern Tasman Sea during Thursday, by which time its easterly fetch should be well established, and generating strong swells that are due to arrive sometime later Friday.

At this stage it’s hard to be confident in the actual timing of the new swell, mainly because it’ll be hard to distinguish from the pre-existing energy. Thursday’s peak will ease only slowly through Friday, in fact with the Coral Sea ridge maintaining strength through the next two days we’re unlikely to see too much of a drop in size across many exposed coasts.

Where this new swell will be most visible will be at the more sheltered SE Qld points, and also further south from Yamba along the Mid North Coast - which will see slightly smaller surf than locations further north, due to the shorter fetch length. 

I think we’ll probably start to see some new E’ly lines pushing through late afternoon on Friday (i.e. after 4pm) though the evening is where we’ll see a more prominent increase ahead of a peak in size and energy through Saturday. So don't get too excited for any new E'ly energy until very late in the day at the earliest. 

This weekend (January 2nd - 3rd)

So, this east swell will peak on Saturday. And now we’re a little closer to the event, we can start to hone into the specifics.

Firstly, I think the models are undercooking the size of this event (in comparison to the current short range S/SE swell, which they’re overcooking as per usual). The consolidation of the tropical low (warm cored) and the mid latitude low (cold cored) is often underestimated by computer models, and I think we’ll end up seeing stronger surface winds than the current guidance is suggesting (35-40kts, see below).

Additionally, the broader system is moving slowly south-west, and the developing lows within are expected to push slightly faster to the west (almost slingshotting around the parent), which should set up a captured fetch scenario - which essentially generates bigger, stronger swells than the theoretical maximum. They'll also be working on quite an active sea state generated by this week's strong S/SE swells.

One other factor that’s worth considering - particularly for inner points north of the border - is that the maximum fetch strength is reached Thursday morning, as it tracks close to the tip of New Zealand’s North Island, concurrently orientating itself in an E/SE direction. 

This is around 30S, and further south, and is therefore south of SE Qld's latitude, which means the swell direction will essentially swing from the east to the east-southeast as the swell reaches a peak. This subtle difference in swell direction may prematurely ease wave heights across some of the more protected locations in SE Qld, and is therefore worth considering. But for locations south of the border, we probably won’t see much difference in size regardless if the swell is east or east-southeast.

The other positive aspect of the weekend’s swell: the local winds. The strong ridge across the coast this week will have relaxed by Friday night, and should result in early light SW winds across most locations, tending moderate S/SE throughout the days. Winds may freshen a touch into Sunday but we’re still looking at early periods of light SW winds in many spots.

As for size, Saturday should see a peak with 5-6ft+ sets across exposed Northern NSW coasts, probably a fraction smaller north of the border due to the aforementioned directional characteristics, but certainly smaller across various points and protected locations. 

Surf size will ease slowly into Sunday but should still remain very solid at exposed Northern NSW beaches with set waves between 4ft and maybe 6ft at times in the morning, smaller into the afternoon. More noticeable on Sunday will be an easing trend across SE Qld though the outer points should still see great waves around 3-4ft. 

Next week (January 4th onwards)

I’m still keeping an eye on additional tropical developments within the large low pressure gyre across the Tropical South-western Pacific Ocean. TD05F is current west of the Cook Islands and is expected pass south of Samoa tomorrow, and will probably develop into a Tropical Cyclone. 

This system is then expected to continue meandering westwards towards Fiji (which may cause some problems locally around Jan 2/3/4), all the while with a strong trailing fetch extending south to New Zealand latitudes. 

This should set up a strong secondary E/NE thru’ E’ly groundswell arriving later Monday or early Tuesday, building up towards a strong, albeit inconsistent peak that afternoon or into Wednesday (set waves somewhere in the 4-6ft range at exposed beaches at this stage), before easing slowly through the rest of the week. As I mentioned on Monday, I’d be surprised if we didn't continue to see smaller but very useful easterly swell across the Northern NSW and SE Qld all the way up until next weekend.

In addition to this, a modest stationary SE fetch through the Tasman Sea over the weekend (the remnants of the system responsible for the weekend’s E/SE swell, actually) will provide moderate SE swells through the first half of next week. 

So the long and short is that we have a bucketload of swell on the way for the next week and a half at least. Additionally the long range models are suggesting a deepening coastal trough across NSW early next week that could very well eventuate as an East Coast Low by Tuesday afternoon or Wednesday. But that’s still a long way off yet - more to be discussed on Friday.

Until then, enjoy the windy waves!