South-east Queensland and Northern NSW Surf Forecast by Steve Shearer (issued Wed 10th August)

Forecast Summary (tl;dr) 

• More solid SSE swell Wed with mod/fresh SW-S winds
• Better angled SE swell Thurs, easing Fri with light winds
• Small leftovers Sat with W’ly winds
• Slight kick in E swell Sun with offshore winds
• Small, long range E swell Mon, holding Tues, easing Wed
• Good quality E swell building Mon, persisting Tues-Fri at fun levels as “trough-block” forms in Coral Sea/South Pacific
• S swell pulses likely Tues-Thurs as Tasman low moves slowly E next week
• More action ahead medium term from a variety of sources, stay tuned for updates.

Recap

An initial pulse of directional S swell faded through yesterday with a below expectation size in the 2ft range, and a late kick in new SSE swell lifting heights to 3ft in NENSW. Today has seen much stronger SSE-SE swell in the 3-5ft range in NENSW, with the more favourable angle seeing some 3ft+ surf in SEQLD, mostly on the Gold Coast. WSW winds are now tending fresh S’ly, confining cleanest conditions to the Points.

Plenty of energy in NENSW today from the SSE

Swell angle also favoured more energy getting north of the border

This week (Aug 10-12)

The multiple fetches coming off a Tasman low near New Zealand anchored by a high just east of Tasmania are now starting to wane. Current ASCAT (satellite windspeed) passes show a weakening fetch of SE winds in the Central/Northern Tasman and a thin fetch of strong winds out of Cook Strait. That will lead to a slow easing trend through tomorrow, accelerating into Fri and the start of the week-end.

In the short run and with high pressure moving into the Tasman and weakening, enveloping most of the Eastern seaboard in a regime of weak pressure gradients we’ll see light winds develop tomorrow with light a’noon E to NE’lies kicking in. Typical for late Winter/early Spring. Get on it tomorrow with the last of the strong S/SE swell peaking in the morning with 4ft surf, bigger 5ft sets at known S swell magnets in NENSW, smaller 3ft in SEQLD, easing slowly through the day. Light offshore breezes should carry well into the middle of the day before they tend onshore.

Friday looks like a fun mop-up day for the beachies with a mix of leftover SE energy and some E/SE swell from the Cook Strait fetch. Expect some 3ft sets through the morning at S exposed breaks easing during the a’noon. A complex low approaching from the W will see NW to N winds, likely tending more W/NW early. 

This weekend (Aug 13-14)

Not a great deal of action this weekend. The weather is complex with an inland low drawing down Indian Ocean moisture into Western NSW- a sign of the negative IOD. 

That will see a developing W’ly flow, extending across most of the weekend and into next week, as the low moves into Bass Strait and becomes slow moving.

Expect a N to NW flow to tilt W’ly by degrees on Sat with a mix of small NE swell and E swell from infeeds into the low as well as some leftover SE swell. That will see a few 2-3ft sets early across open beaches- mostly 2ft- clean under prevailing offshore winds.

We should get a continuation in small E swell on Sunday as swell trains from a longer range E tradewind fetch feeding into the low complex make landfall. Keep expectations pegged, we’re still only looking at 2ft surf tops, but worth a look under continuing W’ly winds. 

Next week (Aug 15 onwards)

Interesting week ahead next week, although with so much model variability between runs and between models it’s likely we still have some significant revision in store before things get “set in stone”.

The complex low moving into the Tasman is likely to remain slow moving, initially with a fetch on the southern flank of the low outside our swell window, aimed at areas from Tasmania southwards. 

Infeed into the low stretches up into the Coral Sea, where it becomes part of a tradewind belt, and is expected to see the E to E/NE swell build a notch into Mon, with sets to 2-3ft under a freshening W’ly to WSW’ly flow. Through the a’noon, SW winds off the Gippsland to Bass Strait region are likely to generate new S swell, possibly nosing into the Mid North Coast before dark.

By Tues those directional S swell trains will likely see a few small west from the S across NENSW, in the 2-3ft range, more likely in the a’noon, as the low deepens and a fetch of strong winds to gales develops proximate to the NSW Coast.

In addition to the S swell, E swell being generated by a fetch feeding into the low and a long trough extending up into the Coral Sea and near South Pacific, will continue to send swell from that quadrant in the 2-3ft range. 

Another, even longer range fetch in Tahitian longitudes, will send some even longer period E swell through Mon PM to Wed with very inconsistent 2-3ft+ sets.

That E’ly fetch is migrating Eastwards as it develops and strengthens, reducing the swell generating potential, compared to analogues of the recent past. Most notably, the “trough block” swell of July last year.  Nonetheless it will still see sets to 2-3ft Wed, building into Thurs with bigger 3-4ft surf, extending into Fri from this source.

E swell is likely to be over-shadowed substantially by short range S swell generated by SW-S winds adjacent to the NSW Coast as the low slowly moves into the Tasman Sea. A late kick in size Wed across the Mid North Coast, Thurs for most of the region, should see some bigger 3-4ft sets before much more solid 4ft surf on Thursday, smaller in SEQLD. We’ll pencil these sizes in for now and finesse on Fri. 

Friday sees easing S swell and quality E swell from the trough block with offshore winds continuing as the low slowly exits the Tasman.

Longer term and it looks like an active period ahead. Cold fronts are stacked by the end of next week, suggesting winer S swell pulses, and we’ll be keeping eyes on the South Pacific for both the “trough block” set-up, which may linger and a more distant sub-tropical low forming on the edge of the swell window. It looks better aimed for the sub-tropics but confidence this far out is extremely low.

Check back Fri for the latest update.