South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Monday 13th January)

Best Days: Strong S'ly swell Tues across Northern NSW, though inconsistent and easing into the afternoon. Small mix of swells elsewhere, ahead of a long spell of E'ly energy, including a cyclone swell for next week.

Recap: Small trade swells built across SE Qld and Northern NSW over the weekend. Saturday was pretty slow and lacklustre with N’ly winds across SE Qld and developing S'ly winds across the Mid North Coast (and eventually the Northern Rivers late), but Sunday was more fruitful with S'ly winds and a combo of swells building to 2-3ft across most locations during the day (including the southern Gold Coast points), with bigger though wind affected waves south from Byron. Today’s been a mixed bag. A new long period S’ly swell delivered a peak in size around 6ft across Southern NSW, but I haven’t seen anything bigger than 3ft at Coffs Harbour’s seemingly reliable south swell magnets. In fact, the Gold and Sunshine Coasts managed 2-3ft sets of trade swell today, and there’ve even been some 3-4ft sets across the Tweed Coast today. Long period energy (~20 seconds) was detected at the Tweed buoy from lunchtime onwards but we’re currently well short of size expectations out of the south.

Tweed buoy data showing the new energy at 20 seconds this afternoon

About the biggest set I've seen at Coffs this afternoon

Plenty of sets at The Pass mid-afternoon Monday

Obvious trade swell at Surfers late today

Late Monday sets at Snapper

This week (Jan 14 - 17)

It’s hard to have confidence where we are with the current southerly swell cycle. And this can affect the short term outlook quite a bit.

Based on Southern NSW buoy data, wave heights (and surf size) have eased quite a bit since a mid-morning peak, so ordinarily it’d be assumed that this swell delivered a much briefer peak than expected, and we’d correspondingly lower estimated for Tuesday, noting that there’s a time delay for arrival across Northern NSW (so, the period of 6ft sets across Sydney around 7am should have been into Coffs some time around 3pm, given the ~16 second swell periods). A later arrival is calculated for Far Northern NSW, of course.

However, we’ve been getting regular reports from the NSW South Coast and also East Coast Tasmania - and they’re still seeing quite solid surf this afternoon. This suggests that there’s still some energy left in the tank. And, the Sydney buoys have pulsed a little in the last few hours too. So this give hope that perhaps the first phase of swell was simply poorly aligned for our region, and there’s better energy to come.

But do however have ten hours of darkness to consider before sunrise Tuesday arrives, and with an inevitable downwards trend expected at some point on Tuesday, we need to be careful not to over-steer.

So, taking a deep breath: on Tuesday I think we’ll see inconsistent sets between 4ft and maybe 6ft across reliable south facing beaches south of Byron.

Elsewhere, expect smaller surf. This includes SE Qld, where we’ll see similar levels of diffracted S’ly swell and small trade swell offering 2-3ft waves across most of the open beaches and outer points (smaller running down the inner points). Exposed northern ends should see occasional larger sets though.

There’ll also be a secondary E’ly swell in the water across the Mid North Coast and southern parts of the Northern Rivers, generated by a modest fetch at the bottom of a broad surface trough lying across the western Tasman Sea. This should produce fun waves around the 3ft mark at exposed beaches in the morning, though this swell will be easing during the day.

As for conditions, model guidance has an existing ridge across the SE Qld coast easing overnight, and winds becoming light in most locations. The only location that is probably at the most risk of NOT seeing favourable light winds (or at least a period of early sou’westers) is the Sunshine Coast. Otherwise I reckon we’re in for reasonably good conditions on Tuesday. 

Wednesday will then see a slack period (light winds and sea breezes across most coasts) everywhere, before a Tasman high swings to the wind to the NE for the rest of the week, remaining light to perhaps moderate across SE Qld and Far Northern NSW, but becoming moderate to fresh N/NE across the Mid North Coast. Thursday looks to be the windiest day of the two.

As for surf, we’ll see easing S’ly swells through Wednesday (early 3-4ft sets at south swell magnets south of Byron, much smaller elsewhere, easing by a foot or two during the day) but more importantly, a ridge of high pressure will maintain 3ft+ of peaky trade swell across most northern coasts from Wednesday through Friday, a little smaller across the Mid North Coast. It’ll be a little sluggish on the full tides and there’ll be slow periods at times, but most locations should have waves each day.

One last source (that probably won’t produce anything rideable, but is worth mentioning anyway) - a deep, poorly aligned polar low well below SA right now may generate some small flukey S'ly swells at south swell magnets south of Byron later Wed/Thurs but no major size is expected (perhaps the odd 2ft set if we’re lucky).

This weekend (Jan 18 - 19)

Persistent local troughiness will maintain generally light variable winds across all coasts for the weekend though there is risk of a northerly incursion from time to time. But on the balance conditions look reasonably OK for surfing. There’ll certainly be a period of lighter winds between Thursday, and an expected resumption in synoptic northerlies due around Monday.

As for surf, we have only one swell source on the cards, and it’s looking very promising for next week - but the weekend may experience a low point between energies.

Our trade swell for this week will have been generated by a broad fetch currently sitting below New Caledonia. Later this week, an approaching Tropical Cyclone near Fiji will broaden a second ridge to the north-east of New Zealand, and the ridge below New Caledonia will weaken. Swell energy from the new ridge is expected early next week, but the weekend is at risk of falling wave heights as the first swell eases and we await the arrival of the new energy. 

At this stage I’d be surprised if size dropped below 2ft+ at most open beaches, so with reasonably good conditions for the most part there’ll be fun beachies on offer. 

Let’s take a closer look on Wednesday.

Next week (Jan 20 onwards)

A large tropical cyclone is expected to develop north of Fiji over the coming days (it’s current tagged by JTWC as INVEST 93P) and the models have moved around on its future developments since Fridays notes were issued.

We’re now looking at a southward track to the east of Fiji (instead of the west), and this TC is now expected to become much broader and stronger, though will move a little faster through the swell window and eventually take up residence to the east of New Zealand, inside our swell shadow. For the record, we're looking at some pretty big waves across the NZ North and East Coast next week, if you're that way inclined. 

Monday will see the first energy from this cyclone across across the East Coast, and I think there’s potential for a peak in size around Tuesday or maybe even Wednesday between 4-6ft at exposed spots. However, there’s still not a lot of confidence in the way this cyclone is likely to develop, and at the moment the strongest winds (which could otherwise be worth another two or three feet) are modelled to be aimed away from our region, both up into Fiji/Vanuatu and also south towards New Zealand's East Coast (see below).

So, let’s keep a close eye on things as there’s a lot of potential in the long term charts. As a minimum, we’re looking at a whole week of useful, underlying trade swell around 3ft+ but let’s hope there’s a few bigger days in the mix as well.

As for conditions, the latest guidance suggests N’ly winds, but it’s too far out to be confident in this either. So, don’t write it off just yet.

See you Wednesday!