Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 30th August)

Best Days: Thurs: large building S'ly swell though wind affected. Fri: steadily easing S/SE swell, rapidly improving conditions. Sat: clean leftover S/SE tending SE swell. Tues/Wed: flukey though clean S'ly swell with offshore winds. 

Recap: Monday’s large S’ly swell eased steadily through Tuesday and conditions were generally favourable as winds swing offshore. Today we’ve seen much smaller S’ly swell plus some small E’ly groundswell from a fetch north of New Zealand late last week. Size is in the 2-3ft range and winds were light and variable until lunchtime ahead of a gusty S’ly change early afternoon. 

This week (Aug 31st - 1st Sep)

In Monday’s notes I discussed a new Tasman Low that was expected to develop in the central Tasman Sea on Thursday, in the lee of today’s southerly change.

Over the last 48 hours, the models have sped up the evolution of this system and also steered it closer to the coast. It is currently forming E/NE of Tasmania, and will drive southerly gales through our immediate S/SE swell window overnight into Thursday morning, bringing forward the timing of the expected new swell. 

Additionally, as a result of the low being closer to the mainland, the peak surf surf size will be a little bigger than Monday’s notes indicated (which was 4-6ft+ south facing beaches, bigger in the Hunter).

However, the downside is that Thursday will be quite wind affected with mainly fresh S/SW tending S’ly winds (isolated regions of SW winds are a low chance early morning).

Most south facing beaches should push a solid 6-8ft by Thursday afternoon as the groundswell reaches a peak. The early morning will be smaller, with a greater percentage of short range S’ly energy. Bigger sets are likely across the Hunter.

However, with the accompanying winds surface conditions will only be clean at protected southern ends. 

Friday still looks like the pick of the next few days. Wave heights will trend down from Thursday’s late peak, but winds will veer SW in most locations, even W/SW - the only region for concern is the Hunter which may see a lingering S/SW flow.

South facing beaches will ease slowly from 4-6ft to 3-5ft though the Hunter will see bigger waves as per usual, and the swell direction should veer more S/SE thanks to a supporting fetch below the Tasman Low. Expect smaller surf at beaches not fully exposed to the south. Conditions may see a slight wobble early morning but should clean up throughout the day.  

This weekend (Sep 2nd - 3rd)

Saturday looks like the pick of the weekend. The fetch responsible for the last swell over the next few days will weaken but still remain active Thurs/Fri just off the SW tip of New Zealand’s South Island. In fact even by Saturday morning there’ll still be a tiny region of leftover gales in the swell window, though it'll rapidly subside during the day. 

This means we’ll see only a slow easing trend from the S/SE, with the swell direction even tending SE. Our model has 3ft at most open beaches on Saturday morning but I reckon this may be a slight undercall, with a chance for a few bigger sets near 3-4ft (whilst the Hunter may see 3-5ft sets at first). Expect size to ease by a foot or so throughout the day; Sunday morning will be down to a peaky 2ft+ from this source with smaller surf again by Sunday afternoon.

Saturday’s conditions are looking great with light offshore winds but N’ly breezes will develop late afternoon and Sunday’s on track for strengthening N’ly winds as a vigorous frontal procession approaches from the west. Small peaky N’ly windswells are likely late afternoon (2ft+ sets at NE facing beaches).

So the only real options on Sunday are early morning when there’s a brief chance for an hour or two of NW in the wind direction. Other than that it looks pretty ordinary.

Next week (Sep 4th onwards)

The local N’ly fetch will clear quickly to the east overnight Sunday so the chances of any leftover windswell early Monday are now slim. As such, surf size will be pretty small to start the week. Strengthening W/NW winds will tend gale force W’ly during the afternoon.

Our favourite acute south swell window (eastern Bass Strait) will fire up on Monday with Tuesday and Wednesday seeing varying degrees of flukey south swell, biggest in the Hunter though south facing beaches in Sydney should see set waves in and around the 3ft mark. It’ll be clean with offshore winds too.

Another strong front/low in this series is then expected to cross the Tasmanian divide, strengthening southerly gales and building southerly swell through Thursday afternoon and Friday, maybe holding into next weekend too. More on this Friday’s update.