Continuing flukey south swells and gusty offshores

Ben Matson picture
Ben Matson (thermalben)

Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 25th June)

Best Days: Thurs: fun south swell early at exposed beaches, with gusty offshore winds. Fri: more south swell (peaking early) with gusty W'ly winds tending NW then N'ly. Late Sun (possibly) and then Mon/Tues/Wed: plenty of reasonably strong south swell, with gusty SW winds.

Recap: Tiny early Tuesday tending flat by mid-morning with howling offshore winds. A small pulse of directional south swell filled in early this morning, offering 1.5ft waves at many south-facing beaches followed by a late arvo kick to 2ft+. However some south swell magnets (i.e. Bondi) have seen much larger sets pushing 3ft+ this afternoon, well above expectations (see images below) - even with nearby beaches remaining tiny (i.e. Maroubra, which was barely 1.5ft).  Late afternoon observations on the Newcastle surfcam showed set waves around the 3ft mark, which is a little under what would be expected given Bondi’s size. Conversely, wave heights from Wollongong to the Far South were considerably smaller, as described in Monday’s notes regarding the “axis of refraction”.

Next week (June 24-27)

Flukey south swells indeed: I gotta say I am quite astonished at some of the sets pushing through at Bondi this afternoon. Considering that the primary swell source was a gale force W’ly tending W/SW fetch existing eastern Bass Strait, it’s amazing that set waves could have pushed overhead at a handful of swell magnets. But, the surfcam doesn't lie.

This creates quite a predicament for the short term forecast period. With this afternoon’s southerly pulse pushing through a foot or so at some beaches above my (admittedly optimistic) expectations from Monday, do I correspondingly increase the forecast for the rest of the week? I’m not convinced that this is the case, because all of the other observations across the southern NSW coast came close to forecast expectations - Bondi’s bigger waves seemed to be somewhat of an outlier.

That being said, the current forecast period is extremely complex and confidence is not particularly high over the next few days, owing to this very flukey source of swell. So your best bet will be to keep an eye on the Bondi surfcam, as it’ll continue to be the best regional barometer for incoming south swell.

So moving on to the specifics: today’s south swell is expected to throttle down as we move through Thursday. We may see some early sets in the 2-3ft range at south facing beaches (smaller waves elsewhere, but a little bigger in the Hunter) but surf size will ease throughout the day. Expect very small waves south of Sydney/Wollongong, even at swell magnets (owing to the regional axis of refraction). Fresh westerly winds will continue to keep conditions clean.

Another pulse of similar acute south swell is then due to push through the southern NSW coast late Thursday (probably overnight) that’s on track to deliver a similar level of south swell for Friday morning. Set waves should approach 2-3ft at exposed south swell magnets (a little bigger in the Hunter) but as per usual it’ll be much smaller elsewhere due to the swell direction, and south of Sydney/Wollongong.

Winds are likely to be moderate to fresh W’ly early but will veer NW then N’ly through mid-late morning as a high pressure system develops in the Northern Tasman Sea and a deep low (another one!) approaches Bass Strait from the west. So, the afternoon may become bumpy at exposed beaches but south swell magnets with protection from these northerly winds should fare well all day, even as the swell slowly subsides into the afternoon.

This weekend (June 28-29)

The weekend’s not looking too flash overall. Friday’s south swell will trend downwards quickly during Saturday and NW winds will strengthen as the low pushes south of the state. So hit up exposed south facing beaches early for the best waves - the Hunter region will probably be the standout performer due to its magnetic properties under funky south swells.

Model guidance is a little split as to the exact timing when this low will (eventually) track into our acute south swell window - some models have Sunday morning, and others have Sunday afternoon. So best case scenario is for a late pulse of south swell on Sunday afternoon (say 2-3ft south facing beaches, tiny elsewhere) but this may very well get pushed back to Monday morning. Either way winds will be strong offshore all day from the western quadrant. I’ll reevaluate this on Friday.

Next week (June 30 onwards)

A similar weather pattern is expected to develop across the SE corner of the country from Sunday onwards, as to what we’ve seen this week.

However this time around we’ll probably be on the backside of the Long Wave Trough, which means we’ll see a stronger, longer and broader southerly fetch developing east of Tasmania - which should generate a bigger south swell for southern NSW early next week - in fact current guidance suggests we’ll be looking at moderate but punchy south swell from Monday morning right through Tuesday and maybe even Wednesday (ballpark 4-5ft south facing beaches). 

The only downside is that winds will be more SW in direction, and may even veer S/SW at times - which will render exposed beaches a little bumpy at times. Still, there’s no shortage of southerly swell on target for next week. I’ll fine tune the specifics on Friday.