Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Saturday 9th September)

Best Days: Sun: very large S'ly groundswell with light winds. Mon: solid but steadily easing S'ly swell with offshore winds. Tues: small leftovers, clean with offshores. 

Recap: Thursday and Friday both delivered strong southerly swells; initially 3-5ft at south facing beaches Thursday before reaching a slightly bigger peak on Friday afternoon around 4-5ft. Today has seen size increase further with 6ft+ sets across south facing beaches. Conditions have been clean with offshore winds. We may see some bigger sets through the afternoon as the final, biggest pulse of south swell pushes through.

Solid sets at Shark Island this morning

This weekend (Sep 10th)

Looks like Wednesday’s model run was pretty good. The leading edge of the final pulse of southerly groundswell - the biggest in the sequence - is due across the Far South Coast this afternoon, and should be into Sydney around dinner time or early evening. 

Core wind speeds around the responsible low have been clocked in well over 50kts so we’re looking at 18-19 second peak swell periods as the swell front hits; of which the sheer length and breadth of the fetch will ensure a very large swell event for Sunday morning. 

South facing beaches across the Sydney region should see solid 8ft sets at times, and offshore bombies as well as some sections of the Hunter coast should see considerably larger surf in the 10ft+ range. It’s going to be a strong, heavy swell with a lot of water moving. However beaches not directly open to the south will be considerably smaller - around 5-6ft at most open beaches and down to 3-4ft at protected southern ends. Wave heights will probably peak through the early morning and then ease into the afternoon.

Incredibly, local conditions are looking amazing with light variable winds and sea breezes. So there’ll be plenty of options to pick and choose from.

Next week (Sep 11th onwards)

The first half of next week will see steadily easing swells. Monday morning will see the most size with 4-6ft sets at south facing beaches (still pushing 6-8ft on the Hunter) easing by two or three feet by the afternoon, and it’ll be nice and clean with mainly light NW winds. Once again, expect much smaller surf at beaches not completely open to the south.

Surf size will then ease further into Tuesday, from 2-2ft to 1-2ft at south facing beaches, remaining clean with light offshore winds from the NW.  By Wednesday we’ll be down to very small residual surf right across the coast.

Late Wednesday or early Thursday should see a small pulse of unusual, long range SE groundswell - the models aren’t picking it up very well, but in the absence of anything else it’s worth keeping an eye out for it. It will be generated over the coming days from a frontal system related to the enormous broad scale low pressure system associated with the current Tasman Sea frontal passage. The primary low will be located east of New Zealand, and a smaller, secondary polar low to the south-east is expected to slingshot to the west, around the bottom of the parent system, up into the SE Tasman Sea. It’ll generate just a small flush of SE swell but could light up some exposed beaches with very inconsistent 2ft sets. 

However, if it doesn’t arrive until Thursday, it may be hard to discern from a local building S’ly swell, originating from another vigorous front exiting eastern Bass Strait, driving W/SW gales into the Tasman Sea. This should building S’ly swells up to 3-5ft at south facing beaches by the afternoon (smaller earlier) though it’ll be windy with fresh W/SW winds locally. This swell will peak overnight or possibly early Friday morning and then trend down through the day as winds revert back to a light offshore. 

Looking towards next weekend, and further small to moderate S’ly swells from similarly rapid transitioning frontal systems are on the cards. More on this in Monday’s update.