South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Monday 5th January)

Best Days: Tues: small pulse of trade swell with early light winds. Wed/Thurs: stronger round of trade swell with good winds for semi-protected points in SE Qld and Far Northern NSW. Late Sun/Mon onwards: likely to be plenty of trade swell with a chance for a sizeable pulse of E'ly groundswell.

Recap: Onshore winds remained generally light to moderate in strength for much of the weekend (north of Yamba) so surface conditions were fun and generally workable. However NE winds were quite fresh and gusty along the Mid North Coast Saturday afternoon and Sunday. The expected pulse in E’ly trade swell fell short of size expectations (in SE Qld/Northern NSW) which was a little disappointing, but most open beaches still delivered fun waves. 

This week (Jan 6 - 9)

Local winds are expected to maintain a familiar trend all week.

A large high in the Tasman currently is currently directing a firm ridge against the Queensland coast. As it tracks slowly eastwards, a new ridge will develop along the Southern NSW coast. However, between the two ridges the pressure gradient will be (for a while) slacker, resulting in lighter winds. This looks to be somewhere in the Yamba-to-Tweed region; north of here we’ll see freshening SE winds, to the south we’ll see freshening NE winds. In the middle, winds will be lighter and more out of the east.

In fact winds should remain lighter in the south through most of Tuesday and Wednesday, it’s Thursday onwards (and maybe not until the middle of the day) where we’re likely to see a lot more strength in the local airstream.  

As for swell, the broad persistent trade flow across our entire east swell window will continue to generate fun surf for the coast. We’re looking at a small pulse on Tuesday with a bigger round of energy on Wednesday, but based on the weekend’s performance I’ve pegged back wave heights a little. The Sunshine Coast should see the most size with occasional sets at open beaches in the 3-5ft range through Wednesday, but these locations will be bumpy and you’ll be best off at the protected points (where it’ll be smaller, and cleaner).

Wave heights should reach 3ft to almost 4ft on the Gold Coast (a little smaller running down the semi-exposed points) and as you then head south of the border wave heights will fall away to 2-3ft across the Mid North Coast. 

This swell cycle should hold through early Thursday before slowly easing into the end of the week and the weekend.

This weekend (Jan 10-11)

The surf forecast is looking pretty good for some coasts this weekend, but winds may spoil it elsewhere. 

We’re likely to see a similar level of trade swell as per Thursday/Friday both days, somewhere in the 3-4ft range across the Sunshine Coast, around 2-3ft+ on the Gold Coast and then slightly smaller surf south to the Mid North Coast.

Local winds look like they’ll become a problem in southern regions though as a developing trough over the SE corner of the country squeezes the coastal pressure gradient, strengthening NE winds about most regions north to around Yamba. 

North of here winds will be lighter and more easterly in direction on Saturday (possibly light/variable early), then Sunday has a couple of curveballs on the way with freshening nor’easters a possibility depending on how the models evolve. Let’s check back Wednesday to see how it’s all panning out.

Next week (Jan 12 onwards)

The stationary trade belt across our eastern swell window is a beauty, and it’s going to be a source of quality surf for quite some time.

In addition to a standard level of useable trade swell, we have two modelled features that could significantly enhance the wind field across the Northern Tasman Sea and therefore potentially deliver much bigger waves to parts of the East Coast.

The first region of interest is the waters south of Fiji. This looks to be an area of enhanced activity as a Tropical Depression slowly develops during the middle of this week, and slowly retrogrades to the coast as we head towards the weekend. 

There are several reasons for the importance of this scenario: firstly, with the trade belt having been established for such a long time (by mid-week, that is), the waters will probably become “fully developed” (which means that they will have reached the maximum wave size that can be generated by the existing fetch).

However, there are some non-modelled aspects of “fully developed” sea states that also need to be taken into account. Firstly, because these synoptic events occur over greater time scales than usual (ie slow upramp/downramp periods), we often see good surf persisting through a greater portion of the Long Tail.

Secondly, if a more significant feature develops on top of, or moves into the waters of a “fully developed” sea state, then it is already beginning swell production with a healthy head start. So this means it requires less time and energy to generate a much greater swell event.

And thirdly, a ‘retrograde’ (or westward) storm track within this ocean basin increases the chances for a ‘captured fetch’ scenario, which further enhances wave heights above what would be typically expected from a fetch displaying such characteristics. Captured Fetches occur when the storm’s forward speed is approximately equal to the speed of the swell its generating (which itself is a function of the fetch’s wind speeds). 

And… that’s what is being proposed by some of the models right now, in the perfect swell window for much of the East Coast - initially north of New Zealand, and then north-west (as the depression tracks westward).

If this all happens as is currently expected, we could be looking at a solid 6-8ft E'ly groundswell across exposed parts of Northern NSW and SE Qld sometime later this weekend or early next week (Jan 11/12 ish). Sure, it's a very optimistic outlook but the atmospheric lead up over the last week has been ideal and we are well overdue for a quality groundswell of this kind.

And lastly - some of the global models are going all out with Tropical Cyclone developments in the Coral Sea this week (one starting near the Northern Solomons mid-week, then tracking south, with a second cyclone forming near Cape York and tracking SE through the Coral Sea).

Whilst this model data needs to be taken with a liberal grain of salt, it’s completely plausible given the active monsoon burst across the top end in association with the passing MJO phase.

So, it can’t be ruled out - in fact I’d be very surprised if we didn’t see a Tropical Cyclone (or two) develop somewhere in the Coral Sea over the next week and a half. But whether they turn into beneficial swell generating systems remains to be seen. Stay tuned to Wednesday’s notes for more.