South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Monday 3rd February)

Best Days: Tues PM onwards: fun waves at outer SE Qld points. Stacks of surf for the rest of the forecast (this week, next week and beyond), though with a tricky wind outlook - however there'll be plenty of size later this week and (moreso) later this weekend / early next week. 

Recap: The weekend was a little mixed as expected. the Mid North Coast was largely wind affected, but SE Qld and parts of far Northern NSW picked up early windows of light NW winds, which helped to offer small fun waves at open beaches with an E’ly swell reaching 2-3ft across the Sunshine Coast, with gradually smaller surf as you headed south from the Gold Cast. Today, freshening northerly winds across northern regions accompanied a slowly easing E’ly swell. It’s worth highlighting today’s wildly variable conditions across the Mid North Coast, too: overnight N’ly winds swing fresh S/SW winds before dawn, eased to become variable mid-morning, then strengthened from the NE before a powerful thunderstorm crossed the region, dumping 20mm of rain at Coffs Harbour and bringing 40kts S/SW wind gusts. The storm has now passed and N’ly winds are now gusting 20kts out of the north again.

Monday afternoon glass off at Yamba in the wake of the t'storms

Fun E'ly swell on the Sunshine Coast this morning

Hammering northerly at Snapper this arvo

This week (Feb 4 - 7)

A gusty S’ly change is moving along the East Coast. It should be very close to the border around sunrise, and will extend quickly north into the Sunshine Coast by mid-morning. 

Strong S’ly winds trailing the change will rapidly build S/SE swells across the Northern NSW coast though exposed spots will be horribly wind affected (4-5ft+ by lunchtime), and initially there won’t be enough size or period for sheltered points, though they should have small options into the afternoon.

The SE Qld outer points will pick up a decent increase into the afternoon (it’ll be tiny early) and should push into the 3ft+ range by the end of the day. However, expect much smaller wave heights at sheltered spots. Exposed northern ends and south facing beaches should see bigger surf in the 3-4ft+ range but it’ll be too windy to surf. 

Winds will ease back across most of Northern NSW into Wednesday, but we’ll see lingering fresh SE winds throughout Far Northern NSW and SE Qld as a high pressure system in the eastern Tasman Sea anchors a temporary ridge through the Coral Sea. More importantly, this ridge will align itself more perpendicular to the coast (than the approaching S’ly change) which will tilt the swell direction more to the E/SE, which means a little more penetration into sheltered spots - though this will be with a slight easing trend overall. So, expect steadily easing wave heights across most of Northern NSW into Wednesday though SE Qld should retain 3ft+ sets at outer points, and there’ll be a little more size (than Tuesday) across the inner points too.

The rest of the week looks pretty dynamic. 

Firstly: long range groundswell sources, unrelated to local synoptics.

Although it'll be almost invisble beneath the local noise, Tuesday and Wednesday will see a small SE groundswell, sourced from a polar low off the Antarctic ice shelf late last week, well below New Zealand (it was mentioned in last Monday’s and Wednesday’s notes, but inadvertently omitted in Friday’s). 

Additionally, a strong but poorly aligned front/low passing south of the Tasman Sea over the coming days (see below) will generate a decent S’ly swell for south facing beaches south of Byron, building on Friday and adding inconsistent 3-5ft sets to the swell magnets. However by this time we'll see more dominant local swells in the mix.

So, back to the local synoptics. A trough is expected to develop along the entire NSW coast as the week progresses, before slowly dragging to the south, spinning up a series of small but tight low pressure systems adjacent to the coast - one of which may end up being an ECL (most likely on the weekend, and most likely off the Sydney coast). And to cap it off, a strong high in the eastern Tasman Sea will anchor in the whole pattern ensuring a long-lived event. 

Although the core fetch around this developing trough will move south - sliding slowly out of the swell window of more northern regions - the anchored fetch across the northern Tasman Sea will maintain a background E’ly swell of at least 3ft all week. 

Locations closer to the axis of the trough will see larger surf, though it’s difficult to have any confidence in size and timing. The most likely scenario is a building trend on Thursday, peaking Friday, though the biggest waves will probably be across the Mid North Coast by this time (5-6ft perhaps?), with smaller surf to the north.

The other factor to consider are the local winds.

Complex troughs with small embedded lows near the coast are probably the most the most difficult weather systems to have any certainty in, and this one looks like being as hard as they come. For the most part, the overall trend will be gusty E’ly winds south of the trough (somewhere near Byron Bay early Thursday, Evans Head late Thursday, Coffs Harbour early Friday, Seal Rocks late Friday), and variable winds north of the trough (variable means “from any direction", which includes onshore).

But, I’m reasonably confident that most of SE Qld and parts of Far Northern NSW will see pockets off offshore winds through this time frame, with a mix of swells as the trough develops, probably reaching 3-4ft across most coasts by Friday. 

In any case, it’s a very dynamic system so you’ll be well advised to maintain a flexible schedule for much of the week, as there’ll be worthwhile waves most days if you’re prepared to put in some legwork.

Let’s take a closer pass on Wednesday. 

This weekend (Feb 8 -9)

So, this enhanced trough/possible ECL setup will probably reach maximum strength later this weekend off the Southern NSW coast, and early next week will see a peak in surf size.

Although the trough will be focused south of our region, we’ll see a corresponding broadening and strengthen got the supporting right through the Northern Tasman Sea, which means E’ly swells will rebuild back into the weekend. Ballpark estimations are for a peak somewhere around 4-6ft, more likely Saturday with a minor, brief easing trend on Saturday. Although most coasts should see this swell increase, I’m not quite sure where the largest waves will be focused - it may be across the Mid North Coast, closest to the E/NE infeed into the developing (possible) ECL.

Onshore winds will probably accompany Sunday’s building trend but we may see a period of variable winds persisting from Friday into Saturday across most coasts. 

So, there’s stacks of swell in store for the weekend, we’ll just have to pick the eyes out of the winds. 

More on this in Wednesday’s update. 

Next week (Feb 10 onwards)

Maximum surf size from the latter stages of the enhanced trough/possible ECL are likely early next week, though with the source located so close to the coast, the wind outlook is simply too tricky to call (see the two charts below, spaced 24 hours apart - Sunday AM and Monday AM). Exposed parts of Southern NSW could be looking at easy 10ft+ sets though we'll see smaller surf as you head north from about Seal Rocks or Port Macquarie.

I suspect that unless the synoptic outlook changes a whole heap, we probably won’t have much confidence in this until a day or two prior. Winds and weather look equally dicey. It's always difficult to lower expectations when the swell charts are lighting up red and purple, but we need to be cautious in our expectations from this event as there are quite a few synoptic negatives to be mindful of. 

Also, there’s quite a bit of rain expected with this event so water quality may be a little suss for a few days.

In any case, following a (currently expected) peak around Monday, surf size will then ease back to a background trade swell level that could maintain 3-4ft surf across exposed stretches for much of next week, supported from a sustained, broad trade flow through the Northern Tasman Sea. 

Looking further ahead, and the long term looks similarly dynamic with a whole range of tropical sources lining up to deliver a bevy of E/NE swells, including a tropical cyclone to form in the Coral Sea that has potential for another large swell event early in the following week. It’s still a long time away, but the extended forecasts suggests no shortage of swell for the region. Winds remain the wild card.

See you Wednesday!