Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 27th May)

Best Days: Thurs: easing, clean surf. Fri: possible SE groundswell with offshore winds. Sat: small SE and S'ly swell with good winds. Mon/Tues: windy south swell but some workable options.

Recap: Fantastic S/SE groundswell with light offshore winds for the last few days. Strong and well defined, a little inconsistent but otherwise really good autumn waves have been on offer at selected beaches and reefs. Most locations held in the 4-5ft range Tuesday but some swell magnets were reportedly around 6ft. Marginally smaller surf today but equally strong and well defined lines of swell.

This week (May 28 - 29)

Our recent run of excellent late-autumn surf will continue through the next few days. The source of this swell is a series of deep surface low pressure systems south and south-east of New Zealand, related to a slow moving Long Wave Trough over the region. Prolonged gale to storm force S’ly winds about the SW flank of the long wave trough are the primary source, however they did push out of the swell window late Monday and into Tuesday which means we’ll see a slow decline in surf size into Thursday.

That being said, conditions will remain excellent as a slow moving high in the Tasman Sea directs NW winds across the region. Most south facing beaches should see inconsistent 2-3ft+ sets, with smaller waves elsewhere. 

For Friday, we’re still on track for a unique, and probably very good quality SE groundswell, generated by a merging low pressure centre within the broader system SE of New Zealand, on Monday and Tuesday.

Storm force S/SE winds feeding into the parent low seem to have been located just far south enough for the fetch to be placed within our swell window - however the large travel time will shave off a considerable amount of size. But the active sea state that the fetch was working on top of will have also greatly assisted swell production.

Confidence isn’t especially high as to what will eventuate on Friday (due to the rarity of this synoptic setup) but I’ll holding firm with my forecast for inconsistent 3-4ft sets at exposed beaches throughout the day - there will be very long breaks between the bigger waves but conditions should be excellent once again with moderate NW winds. The leading edge should push through overnight Thursday so it’s likely to be in the water Friday morning, with a possible easing trend into the afternoon.

Anyway, we rarely see swells originate from this part of the world so it’ll be interesting to see what eventuates. 

This weekend (May 30 - Jun 1)

Friday’s SE swell - if it pushes through (c’mon! let’s show some positivity!) - will be on the way down through Saturday so apart from some early sets at exposed beaches (2ft, maybe 3ft?), we’re looking at slowly easing swells with moderate offshore winds.

A weakening front pushing east of Bass Strait on Friday may generate some small S’ly swell for Saturday but it’ll likely be smaller in size than the pre-existing SE swell. Conditions look good with freshening W’ly winds though.

On Sunday, surf size is expected to remain very small. We’ll see a minor new south swell push through, originating from the parent (Southern Ocean) low pressure system related to Friday’s front - as it tracks SW of Tasmania on Thursday - but although core wind speeds are very strong, most of the fetch is positioned just outside our acute south swell window. 

As such, I’m not very confident that we’ll see much more than an inconsistent one or two feet of surf at south facing beaches, with tiny to flat conditions elsewhere. These south swells do often produce much better results in the Hunter (2-3ft perhaps) but I wouldn’t schedule a road trip on this basis. Nevertheless conditions look pretty good with offshore winds so keep some time free nearby a south swell magnet if you’re that way inclined.

Next week (June 2 onwards)

The deepening trough north of New Zealand expected from Friday onwards now doesn’t look very good for us - it’s been marginally weakened, but worse - pushed slightly SE in direction, inside the swell shadow of New Zealand’s North Island. There’s a chance we may see some faint lines from this source but with better swell prospects from other regions it’s not worth worrying about.

Otherwise, the models have changed their long term outlook since Monday’s notes, pushing the Long Wave Trough across Tasmanian longitudes around Sunday, driving strong S/SW winds through the southern Tasman Sea and kicking up a new south swell for Monday and Tuesday. This looks good for a peak in the 5-6ft range at south facing beaches (smaller elsewhere, bigger in the Hunter) but with mainly fresh and gusty SW tending S/SW winds. So, options will be limited at many breaks. 

The good news beyond this is that further strong fronts migrating around the LWT during this time will maintain strong southerly swell through the second half of the week, possibly a little bigger than what we’re expecting Monday and Tuesday. In any case this region will certainly be the focus of our attention next week.