Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Fri Oct 22 )

Forecast Summary (tl;dr)

• Mix of easing ESE and small E swell Sat with window of OK winds AM before NE winds freshen
• Stronger ENE swell Sun, with fresh S'ly winds developing and S'ly windswell building PM
• ENE swell peaks Mon, easing back Tues combined with S'ly swell and easing winds
• Strong S'ly swell Tues easing Wed with potential good winds Tues and Wed AM
• Small S swell Thurs, small NE windswell Fri
• More prospects for S swell next weekend as another low moves into Tasman Sea

Recap

Fun sized SE/ESE swells have been in the water there last 48hrs, generated by a weak, but well placed Tasman low in the Central Tasman Sea. Yesterday saw surf in the 2-3ft range with slightly larger 3ft+ surf in the Hunter, with light winds from the SW to SE. Today has seen a slight bump in size from the ESE into the 3ft range with generally clean morning conditions before a light/mod SE/NE onshore flow developed. All in all, plenty of fun waves to end the working week.

This weekend (Oct 23-24)

Still a dynamic weekend f/cast ahead. The current Tasman low has drifted out and become absorbed into a long, NE/SW angled trough in the South Pacific, which is currently organising and energising a broad but thin fetch of E’ly gales from the South Pacific down into the Tasman Sea adjacent to the North Island. It’s a complex wind field which is expected to be quite mobile, but still capable of generating a nice pulse of E’ly swell for the region.

That swell is expected to build in Sunday, along with a fresh S’ly as a low forms East of Tasmania in a trough line.

For Saturday we are looking at swell trains from the more proximate Tasman low, slowly easing through the day. Weak high pressure off sub-tropical NSW generates a NE flow through tomorrow, but there’s not much synoptic strength in it, so early winds are likely to be favourably disposed from the NW before clocking around to the NE and freshening in the a’noon.

Sunday hinges on the S’ly change and that now looks to be in by first light across most of the region, possibly delayed enough on the Hunter for an early window of more WSW winds before the S’ly kicks in. Sunday morning looks under-sized, with mostly leftover ESE swell in the 2-3ft range.

Through the a’noon, longer period E swell is expected to fill in, with wave heights reaching 3-4ft, as well as new short range S swell, up into the 4ft range at S facing beaches, larger 4-5ft on the Hunter. All this will take place under a regime of fresh S’ly winds, so finding protection from the wind will shave off a lot of size from the S’ly swell and make E’ly swells the dominant source. In other words, options out of the wind with E swell.

Next week (Oct 25) and beyond

The new Tasman low East of Tasmania dominates the first half of next week, but it does look a bit less favourable for swell production compared too Wed’s f/cast. Despite the slight haircut in size Mon will still have plenty of surf with E swell from the North Island source in the 3-5ft range, easing back during the day and plenty of mid period S swell. Winds are expected to have S’ly component but with latest model runs keeping the low quite close to Tasmania during Mon morning it’s possible we’ll get synoptic WSW to SW winds through Mon morning. Check comment below for updates over the weekend on winds. There’s still a lot of troughiness lingering along the NSW coast so local wind convergences are likely/possible.

Lighter winds are more certain for Tuesday, which now looks the best day of the f/cast period. The Tasman low reaches peak intensity through Mon, with a compact but strong fetch of gales off the Gippsland and Far South Coast, a fetch that typically favours the Sydney Basin and Hunter Curve. So expect a wide variety in wave heights through the region as some areas dip out due to the fetch position. More likely, the South Coast and Illawarra.

Longer period S swell pushes wave heights up into the 3-5ft range at S facing beaches in the Sydney basin, bigger 4-6ft on the Hunter, with light SW winds early tending to light/mod SSE to SE breezes during the day. Easing E swell should provide a few small 2-3ft sets early before dropping out of the mix. 

Wed sees easing swell and winds with residual S swell in the 3ft range, easing during the day and light land and seabreezes as the Tasman low dissipates and the area comes under a regime of light pressure gradients. 

A couple of days of N’ly winds are expected through the latter part of next week, as weak high pressure at sub-tropical latitudes slowly gets squeezed by another approaching front and trough. Thats likely to lead to couple of days of small, poor surf, especially in the context of the run we have been getting. Small leftover S swells Thurs in the 2ft range, with a developing 2ft NE windswell Friday. Nothing to write home about.

Into the medium term and another mid-latitude system is expected to approach Tasmania next weekend. Models are still divergent on this system with EC pushing it into the lower Tasman, then spawning another low in the Central Tasman among a trough line. That would see S swell likely Sun with major swell potential into the week 1/11. GFS has a more modest, stalled low, which moves into the Tasman as it weakens next weekend. Suggesting much more modest S swell potential into November. With the dynamic and troughy Spring pattern so far, no doubt these prospects will be revised when we come back on Mon.

Check back in then and have a great weekend.