South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Monday 11th September)

Best Days: Tues: easing S'ly swell across Northern NSW, very small in SE Qld. Thurs: possibly a small window of early N'ly windswell as winds swing offshore. Don't expect much away from the Gold/Tweed Coasts. Fri: building S'ly swell in Northern NSW (only small in SE Qld). Sat: small fun leftover S'ly swell in Northern NSW (only small in SE Qld). Sun: chance for a late afternoon of very large S'ly groundswell in Northern NSW.

Recap: Sunday delivered large S'ly swells to Northern NSW, reaching a peak across the Mid North Coast in the morning and the Far North Coast and SE Qld regions into the afternoon. Size was generally up around the 8ft range at exposed south facing beaches with much smaller surf at remaining locations, whilst SE Qld delivered smaller surf up to 3ft+ on the southern Gold Coast points, bigger at exposed northern ends but smaller on the Sunny Coast. Today we’ve seen a slow easing trend, though south facing beaches (such as those near Coffs Harbour) were still seeing 4-6ft sets this afternoon (see surfcam grab below). The Gold Coast managed 3-4ft sets at exposed northern ends this morning (2-3ft on the points) with smaller surf on the Sunshine Coast. Conditions have been clean both mornings but afternoon NE sea breezes each day have created lumps and bumps across the points.

Large S'ly sets persisting at Coffs Harbour around 4pm this afternoon

This week (Sep 12th - 15th)

Surf size will ease rapidly through Tuesday and Wednesday as this large south swell continues to fade. 

Early Tuesday will have the most size - perhaps some stray 3-4ft+ sets at south facing beaches south of Byron (possibly a little smaller on the Mid North Coast, owing to a closer proximity to the swell source) and once again you’ll have to surf early with morning NW winds expected to swing to the NE into the afternoon and freshen. Expect smaller surf at beaches with less southerly exposure, and size to almost halve throughout the day. 

Across SE Qld we’ll be back to the small stuff with the only workable options at exposed northern ends - we should see occasional 2ft+ sets here early (smaller throughout the day) under a NW tending NE wind regime. Don’t expect much, if anything on the outer points.  

Wednesday will see tiny conditions at most beaches with freshening NNW winds as a vigorous front approaches from the south-west. These winds will become quite strong through the afternoon, possibly generating a small N’ly windswell for the Gold and Far Northern NSW coasts, but it’ll be low quality. 

Persistent N’ly winds overnight should slightly muscle up this windswell, and hopefully allow it to persist into Thursday morning. As such there’s a chance for a brief window of peaky windwaves running down the coast early Thursday, brushed clean as a gusty W’ly change extends across the region. The timing on the chance currently looks to be early morning across the Mid North Coast, and mid-late morning across the Far Northern NSW and SE Qld coasts, so expect N/NW tending NW winds prior to its arrival. 

As for size, I’d be surprised if most NE facing beaches saw much more than 1-2ft but we may see isolated NE swell magnets across the Gold and Tweed Coasts pushing 2ft to maybe 2-3ft. It's certainly not worth scheduling your diary around, but if you’re in the area it’l be worth a quick quiz on the surfcams early. Size will then ease throughout the day. 

Strong to gale force W/SW winds trailing the front into the Tasman Sea will then set up an unusual S’ly swell for Friday. Again, it’s hard to have confidence on these kinds of swells because the fetch will be aimed some 150 degrees away from the coast.

However, we often experience a decent spread of energy back to the coast from these kinds of setups - arriving near-simultaneously due to the source alignment - and it’s possible that we could see 3-4ft+ sets across south facing beaches south of Byron, with 2-3ft surf at the exposed northern end of the Gold Coast (smaller at the southern end) and 1-2ft across the northern end of the Sunny Coast (smaller at the southern end). Conditions should be clean with early offshores ahead of light afternoon sea breezes. 

This weekend (Sep 16th - 17th)

Friday’s south swell will ease through Saturday but conditions will be very clean with light offshore winds and afternoon sea breezes. Expect somewhere around the 3ft+ mark across south facing beaches south of Byron, and maybe 2ft at the exposed northern end of the Gold (1ft+ on the Sunny Coast). Smaller surf will then prevail into the afternoon. 

At the same time, a vigorous front will have crossed the Tasmanian divide, and its associated low pressure system is expected to intensify rapidly in the southern Tasman Sea later Saturday, with surface wind speeds upwards of 50kts across its western flank. 

This is expected to produce a brief, albeit very large pulse of relatively long period (given the close proximity) S’ly groundswell to Northern NSW during Sunday, that could easily match the size seen this past weekend.

I’m hesitant to commit to a size (or timing) right now because the low is expected to transition quickly through the swell window, and any small tweaks to its strength, position and/or alignment will dramatically alter the surf size projections. But for now let’s ballpark somewhere in the 6-8ft range for south facing beaches south of Byron by Sunday afternoon (smaller in the morning ahead of its arrival, and smaller at other beaches).

This swell doesn’t look especially well lined up for SE Qld but we could see some late runners across the Gold Coast points in the 2-3ft range, with much bigger surf at exposed northern ends. 

Anyway, we need a few more days to confirm the specifics so check back on Wednesday. 

Next week (Sep 18th onwards)

Sunday’s swell is expected to peak overnight and then trend down steadily throughout Monday. However, the responsible low is forecast to meander about the SE Tasman Sea off the South Island’s West Coast, so we’re looking at moderate+ levels of S/SE tending SE swell through the middle of next week, with some potentially great surf on offer across the region. More on this in Wednesday’s update.