South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Wednesday 8th Feb)

Forecast Summary (tl;dr)

• New S'ly swell for Northern NSW on Thurs, light winds in the south
• Small leftover E'ly swell elsewhere on Thurs, freshening SE winds north from Byron
• Strong, unusual N/NE groundswell building Fri (mainly SE Qld)
• Strong building E'ly swell through Friday; delayed across southern regions
• Large E'ly swells Sat thru' Tues; tricky winds at times

Recap

Peaky mix of south and east swells over the last few days, generally 2-3ft at most exposed beaches. Light morning winds, freshening afternoon sea breezes. 

This week (Feb 9-10)

There’s another round of southerly groundswell moving up the Southern NSE coast today and it’ll provide a nice spread of surf across Northern NSW on Thursday. 

South facing beaches will pick up the most size with sets around the 3ft mark, elsewhere we’ll see a smaller combo of east swell in the mix. SE Qld won’t pick up much of the south swell so it’ll be relying on the east swell, which is likely to ease a smidge from today but should otherwise still offer peaky sets at exposed beaches.

Local winds look OK across most of Northern NSW (light variable early, sea breezes later), though north from Byron and into SE Qld we’ll be at risk of fresh SE winds from the get-go as a ridge of high pressure strengthens in response to the southerly advances of TC Gabrielle in the Coral Sea.

This will affect surface conditions at exposed beaches so you may have to grovel around the semi-protected points for a small wave. Early morning may offer a window of light S’ly winds across the southern Goldy Coast.

Friday looks very interesting indeed.

Northern NSW will see easing S’ly swells from Thursday and there’ll be some minor E’ly swell in the water too, with similar winds as per Thursday.

However, we should start to see some long period N/NE swell appear, generated by the early stages of TC Gabrielle (developing tonight, actually). Model guidance has this particular slice of energy building through the day, reaching a peak later before easing into the weekend, and it’s a particularly unusual combination of period, size and direction for our neck of the woods.

In similarity to how south swells will bypass most of the SE Qld coast but show strong at south facing beaches in Northern NSW, this N/NE energy will probably appear the opposite - showing well at ‘north facing beaches’ (i.e. southern corners in SE Qld), and may bypass broad stretches of the Northern NSW Coast, depending on local bathymetry and land barrier shadows. 

At the same time, we’ll also see a building mid-range E’ly swell from TC Gabrielle, which by Friday morning could very be a Category 3 system, positioned midway between Fraser Island and New Caledonia.

How big will the surf get?

Both swells should be worthy of 4-6ft sets by the afternoon, though the secondary N/NE swell will result in much larger waves at protected spots than we normally see, which may give the appearance of larger surf regionally (one or two swell magnets may pick up 6-8ft sets, though they’ll probably be very wind affected). 

Expect a longer delay on the arrival (and subsequent upwards trend) from both swells, south of Ballina - of which the N/NE will be very flukey in this region thanks to the swell shadowing. 

It’s worth nothing that the modelled strength of TC Gabrielle is capable of a LOT more size than I have estimated, but working against its surf potential is its steady south-east track towards the Northern Tasman Sea. Should it become stationary in the Southern Tasman Sea (with a supporting ridge to the south), we could easily double these height projections.

As it is, there’s only a few spots that’ll handle this size, along with the accompanying fresh S/SE breeze in the north. No prizes for guessing where either. 

Winds should be much lighter as you head south from the Northern Rivers too; still onshore but more manageable with the smaller, delayed surf trend.

This weekend (Feb 11-12)

Over the next couple of days, TC Gabrielle will strengthen considerably and track south-east through the Coral Sea, enroute to the Northern Tasman. On Friday and Saturday we’ll see the cyclone muscle up against a large high near New Zealand, which will broaden and lengthen an impressive easterly fetch along its southern flank as TC Gabrielle undergoes extra-tropical transition.

It’s these developments - fair and square within our swell window - that will generate another four days of large easterly tending east-southeast.

We’ll see the most size across Northern NSW, with slightly smaller surf across SE Qld. Friday’s aforementioned secondary N/NE swell will ease steadily across SE Qld into Saturday so we will start to see a more typical spread of wave heights across the region.

As for size, let’s ballpark 6-8ft sets across Northern NSW both days of the weekend - perhaps a little undersized early Saturday - smaller around 4-6ft at exposed beaches in SE Qld, smaller again along the points.

Interestingly, thanks to TC Gabrielle tracking quickly into the Tasman Sea, the local pressure gradient will be weak over the weekend, resulting in light morning winds and afternoon sea breezes (with a northerly risk for Sunday).

We’ll firm things up on Friday.

Next week (Feb 13 onwards)

As mentioned above, the slow moving nature of (by this time) ex-TC Gabrielle will result in easterly swells holding at a similar size (as per the weekend) through Monday, and probably Tuesday, before easing Wednesday. 

A poorly orientated coastal ridge will bring about a northerly wind risk through this period so let’s not get too excited about the surf potential just yet. 

It's worth nothing that the strength of TC Gabrielle has the potential to generate much larger waves than what I've mentioned above, however the core fetch (see below) will be aimed into the Coral Sea, slightly off-axis for our swell window. If anything, Sunday afternoon and Monday morning could see a period of even bigger surf than I have indicated (i.e. 10ft+ sets in Northern NSW). Let's be cautious for now. Either way, it's very likely to be large and powerful for several days.

There’s nothing else on the long term radar behind this, so let’s see how the model guidance is shaping up on Friday.

See you then!