South-east Queensland and Northern NSW Surf Forecast by Steve Shearer (issued Wed 25 Aug)

SE Qld Forecast Summary (tl;dr)

• Long range E swell event start to show late Wed, inconsistent surf holds from Thurs-Sat with head high sets, easing back Sun
• Mod S swell Thurs, easing into Fri
• Fun blend of SE and E swells this weekend
• New pulse of SE swell Mon
• More SE/ESE swell likely mid next week, revisions likely, stay tuned for details

Northern NSW Forecast Summary (tl;dr)

• Long range E swell event start to show late Wed, inconsistent surf holds from Thurs-Sat with head high sets, blending with dominant S to SE swell
• Strong S swell, easing a notch through Thurs and holding Fri with mostly offshore winds
• Fun blend of SE and E swells likely next weekend
• Another pulse of SE swell likely Mon.
• More SE/ESE swell likely mid next week, revisions likely, stay tuned for details

Recap

Very dynamic 48 hrs has just ensued with a bombing low forming off the NSW South Coast yesterday and a NE windswell that was rapidly cleaned up by W’ly winds generated by the developing low. Fun 2-3ft surf was on offer through the region in the a’noon.

Today has seen a large spike in S swell across NENSW, larger and arriving ahead of Mondays f/cast expectations. Surf showed in the mid morning across the MNC and built rapidly into the 5-6ft range, showing by lunch-time in the Ballina-Byron region in the 3-5ft range but not really making much of an impact north of the border, despite buoys registering the arrival of the swell. W’ly winds had a more NW tilt on them later this a’noon north of Yamba, putting devil winds up the face of regional Points. 

This week (Aug 25-27)

Alright, this vigorous Tasman low will dominate surf and weather for the week and into the weekend. Keeping in mind these systems are incredibly dynamic so small changes in position, strength and movement will have impacts on our surf potential, lets wade in.

Current ASCAT (sat windspeed) passes confirm Mondays f/cast expectations with a thin, coast-hugging fetch of storm force SSW oriented winds. Movement of the low away from the coast, allowing the fetch to become dominated by more favourably oriented S to SE winds on the SW flank of the low has been slowed, which equals another day of directional S swell Thursday, instead of the more SSE swell suggested by Mondays f/cast.

Todays spike in S swell for NENSW is expected to peak through the night and settle down through tomorrow , unfortunately not making much of an impact in SEQLD. Expect 3-5ft surf through most of NENSW tomorrow, with some bigger 4-6ft surf at S swell magnets, though it’s likely they’ll be overwhelmed. SEQLD will be relying more on the long range E swell which has just started to show at low levels. By Thurs long lined sets in the 3ft range should fill in, but expect long waits and inconsistency, especially around unfavourable tidal phases. S swell is likely to top out at 2ft+ on S facing beaches and Northern Corners.

Winds look a bit tricky for Thursday. Slow moving Tasman lows create a synoptic “vacuum” that tends to be filled by devil winds from the N. Offshore winds through the morning are likely to trend N to NE through the day before clocking back around NW later on.

This wind regime is likely to extend from SEQLD down to Ballina or even Yamba so be prepared for periods of N’ly component winds. 

Further south the synoptic W’lies are likely to dominate all day. Expect these devil winds to persist through Fri. 

Moderate S swells continue into Friday. The proximate S’ly fetch along the NSW South Coast weakens right off through Thursday and with a slower movement of the low away from the coast it’ll delay the arrival of better angled SSE/SE swell. An energised Tasman Sea will still provide plenty of energy from the S through Fri with size in the 3-5ft range at exposed S facing spots, grading smaller 3-4 across less exposed spots and 2ft in SEQLD.  This S swell will combine with the long range E swell showing 3-4ft sets, potentially offering up some A frame beachies if you can crack the code. Friday looks well worth a paddle or two.

This weekend (Aug 28-29)

The Tasman low finally moves into better position later Thurs into Fri, weakening as it does so. The weekend still looks great though, just smaller in size due to the declining windspeeds on the SW flank of the low, compared to Monday’s notes. The pattern still looks favourable: a high pressure cell sliding E of Tasmania and a low drifting towards the South Island. That will supply a mostly offshore wind pattern, tending to light seabreezes on Sunday  and great quality SSE/SE swell both days.

Based on current modelling Sat looks a little undersize to start with, likely 3ft, bigger at more exposed magnets. A stronger SE pulse is expected in the a’noon generated by the fetch consolidating later Thurs into Fri. That gives good odds of surf muscling up into the 3-5ft  range in NENSW, smaller 3-4ft in SEQLD, with offshore winds. This will combine with E swell which will be slowly easing back in size and consistency, though there should be 3ft sets still on offer. Saturday looks great. 

Sunday also looks the goods, with that pulse holding in at similar size range and light offshore breezes which should extend through to lunch-time, before winds tend to light nor-east seabreezes. East swell will be dropping back to the 2ft range and becoming marginal through Sunday.

As we mentioned these Tasman lows are incredibly dynamic so stay tuned Fri for a final tune up on size and timing but there’ll be plenty of surf anyway you slice it.

Longer Term (Aug 30) and beyond

Next week looks incredibly dynamic with a complex, unstable Tasman sea set to provide more surf, although model divergence is significant so these calls will be subject to major revision more than likely.

The remnants of this weeks Tasman low drift towards New Zealand early next week. Models suggest a small, weak low forming off Sydney, which is not a swell produce but brings a W’ly change, likely Mon.

This weak low may join with the remains of the current low, re-energising either a fetch near the South Island and/or a fetch out of Cook Strait. 

That would suggest a pulse of SE/ESE swell possibly Wed.

GFS then maintains the SE fetch out of Cook Strait and extends it northwards and into the Northern Tasman/Southern Coral sea as a new high pressure ridge sets up along the East Coast, suggesting a round of E swell mid/later next week.

EC is in favour of the remnants of the low drifting into the South Pacific north of the North Island and forming a broad fetch of SE winds north of the North Island. 

The blocking pattern for S swells remains in place.

Both these scenarios favour NENSW and SEQLD. But don’t get too attached, with so much model instability it’s likely we’ll be making major revisions on Fri. Check back then for the latest.