South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Wednesday 9th March)

Best Days: No great days, though there will be surf around most of the time. Expect very slowly building E'ly swell across SE Qld from Fri thru' Mon (peaking late Sun/Mon), but onshores will maintain below average conditions. Next week has some promise with several additional swell sources. 

Recap: Nothing overly special. A small pulse of E’ly swell delivered a renewal of swell across most coasts on Tuesday however onshore winds came in moderate or greater across locations north of about Yamba (south of Yamba, the early morning generally offered a period of reasonable conditions). This small swell plus some background trade energy has persisted into this morning with similar winds - light to moderate onshore across SE Qld and Far Northern NSW, with light variable winds south of about Yamba. 

This week (Mar 10th - 11th)

No real changes to the immediate forecast. A broad but ultimately moderate band of trades south of New Caledonia are generating small trade swells that will persist about the coast for the next few days, mainly favouring SE Qld and Far Northern NSW in the size department. 

This fetch is expected to muscle up a tad from this afternoon onwards, which should bring about a minor increase into late Thursday afternoon and Friday. But it’s an incremental increase at best and with persistently average surface conditions (read: lingering onshore winds) there’s not much to get excited about.

We may see an early period of light variable winds in some locations on Thursday - mainly south of about Yamba, as we have been seeing this week - but what we really need across SE Qld is a period of moderate offshores to iron out the lumps and bumps from the current onshore flow. This isn’t likely, so the upshot is that surface conditions across northern regions will remain very ordinary for the next few days, even if we’re lucky to see a period of light/variable winds in the mornings. 

Surf size may temporarily dip Wednesday afternoon and into Thursday morning before rebuilding again throughout the day but I can’t see much more than 2-3ft+ max by Friday afternoon. The upper end of this size range will probably be found across the Sunshine Coast open beaches (and maybe the Gold Coast at a pinch), with smaller surf as you track south. Expect smaller waves as you run down the various regional points too (the short swell period means that only shallow, sand bottom points will offer anything worthwhile).

So, keep your expectations low and you’ll find some small peaky beach breaks. But it’s not going to be anything special, and it’s certainly not worth any flexi time from work.

This weekend (Mar 12th - 13th)

The broader trend of a slow upwards increase from Saturday through Monday is still on track.

We’re currently under a blocking pattern consisting of broad, stationary high in the Tasman Sea, and an elongated trough of low pressure across the Northern Coral Sea. The Tasman high is driving a ridge across the Northern Tasman Sea, into the Queensland coast. 

An easterly dip - a small area where the isobars within the ridge bend, or ‘dip’ to the south, strengthening winds and focusing the fetch - has been touted to develop for some time though the models haven’t been especially confident in where, when or how strong. 

It looks like the evolution of this easterly dip will be slow going, which means surf size will build incrementally over the weekend. And because it’ll be associated with a ridge in our immediate swell window, we should see a fairly quick translation at the coast. 

Again, surf size from this episode will mainly produce the biggest waves in and around the SE Qld coasts. Surf size should build very slowly from 2-3ft+ on Saturday morning up towards 3-4ft+ by later Sunday at open beaches, but expect smaller surf south of the border. There’ll be lully periods in the mix, and initially the trade swell could be a little susceptible to the tides however we should see a slow increase in the strength of the swell all weekend.

The only downer for the weekend’s slowly building easterly swell will be the presence of a persistent onshore wind. As mentioned above, even the chance for a period of light variable winds each morning will be tempered by the fact that we ideally need a period of moderate offshore winds to iron out the lumpiness, and this isn’t likely - so at best we can expect plenty of early morning wobble. Otherwise, expect moderate to sometimes fresh E/SE winds throughout Saturday and possibly even Sunday. Winds will be lighter south of Ballina or Yamba (and with a lengthier period of early light offshores) but there'll be less size here. 

Next week (Mar 14th onwards)

So, it looks like our easterly dip is going to strengthen a little more early next week and then track south. The strengthening is a promising sign, but the southward track is concerning for SE Qld coasts. 

At this stage it looks like Monday’s peak will ease a little into Tuesday morning before we see a second pulse of E’ly swell from the dip, however this time ‘round the source isn’t quite as good - despite possibly having a little more strength (and this may change in future mode updates), it’s likely that the fetch will be narrower, won’t have the ridge extension to the coast (a small but useful addition for this weekend’s swell) and it’ll also be tracking southwards, perpendicular to the swell window. So we'll see a swinging swell direction, depending on your coast - but in SE Qld it'll trend E'ly then E/SE, maybe even SE. 

This leads me to cap potential wave heights from this source to something a little smaller than what we’re expecting Monday (3-4ft+ open SE Qld beaches), and it’ll also occur over a smaller period of time. Perhaps a late increase to 3ft+ at open beaches later Tuesday and into early Wednesday, before easing into Wednesday afternoon.

There are a few positives with this pulse though - it’ll favour Northern NSW with a similar level of size (maybe even a shade more, as the fetch looks like it’ll be better aimed here) and the weakening of the coastal ridge will allow for lighter winds in all regions from Monday thru’ Wednesday. It’ll still be onshore but there’ll be less strength overall, and we should see a longer period of light variable winds in the morning, with a little less wobble that what’s expected over the weekend. 

As the E’ly dip continues to travel south, it’ll continue to aim towards Southern NSW and could very well shut off the swell supply to SE Qld. So we are at risk for the Gold and Sunshine Coasts to see decreasing wave heights from Wednesday onwards for a couple of days. However Northern NSW should continue to feel the benefits of smaller sideband E’ly swell. 

That being said, the end of next week has some great potential too.

The southward tracking E’ly dip (likely a trough of low pressure, possibly even a closed low at some point) is likely to merge with a strong ridge building along the Southern NSW coast, sometime during the middle of the week. The most likely outcome of this is the formation of a Tasman Low well east of Sydney however it’s much too early to know whether this system will end up being a major swell producer, and when we may see its produce. 

But, if I had to go out on a limb, it currently looks like we may see swell from a couple of Tasman sources. Initially, Northern NSW should see some building S/SE swell from the southern NSW ridge around Wednesday or Thursday (plus some sideband E’ly swell from the dip) but this would be unlikely to reach SE Qld in any meaningful way due to the swell source and direction. Exposed south facing beaches in Northern NSW may pick up 3-5ft surf from this source; local winds are unsure at this stage though. 

If the Tasman Low ends up developing as suggested above, we’ll probably see this influence the region from later next week and more likely into the following weekend. Such systems usually favour Northern NSW for the most size, with SE Qld typically seeing only half of the size (or sometimes less). 

At this stage there is certainly the chance for a strong SE swell from this synoptic setup but it’s a very long way down the track and we need a lot of things to happen before then. Let’s wait and see how Friday’s model runs are looking.