Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Fri Oct8 )

Forecast Summary (tl;dr)

• Small S swell leftovers Sat AM before N'ly winds kick up
• Small NE windswell Sun with an a'noon S'ly change.
• Rapid increase in S swell Mon with strong SSW/S winds
• SE swell tending ESE Tues, easing through the day with local winds easing
• Possible ESE/E swell Wed/Thurs, with fresh N to NE winds developing
• NE windswell through Wed/Thurs
• Uncertain outlook later next weekend and next week as low moves over Tasmania into Tasman sea, check back Mon for revisions

Recap

Leftover S swell through Thursday saw some clean surf in the 2-3ft range at S facing beaches, with much smaller surf elsewhere. A vigorous Southerly buster worked it’s way up the coast in the a’noon, with windspeeds super-charged by a small trough just in advance of the change. Unfortunately, despite those windspeeds, the fetch was shallow and short-lived and today we’ve got messy, wind affected 2-3ft of S swell across the region. Winds are expected to lay down and turn NE through the later PM hours, offering a grovel up to end the working week.

This weekend (Oct 9-10)

The highly unstable, mobile pattern continues with no major changes for the weekend f/cast. High pressure currently over the NSW/Vic interior races out into the Tasman sea today, energising another round of N’ly winds. 

Leftover S swells from the trough and a compact parent low which transited the Tasman later yesterday into this morning will be on offer Sat morning, with a brief window of more favourable NW winds on the cards before winds tend N to NE and freshen. Expect some small 2ft surf at S facing beaches, bigger 2-3ft on the Hunter, best early before the N’ly winds up. 

Sunday is a game of two halves. Initially mod/fresh N’ly winds are on offer, with small amounts of NE windswell on offer. Compared to Wed’s notes, the N’ly fetch is located further north and pushed a bit eastwards out of the Hunter-Illawarra swell window so keep expectations pegged low. A few 2ft sidewinders are on the menu. 

As we saw on Thursday another vigorous S’ly change is expected to propagate up the coast, likely just after lunch. If you’ve got aspirations for a go out it’s best to get it done before the southerly buster arrives. A slightly cleaner period of NW winds is on the cards just prior to the arrival of the S’ly if you want to try and pick the eyes out of it.

Next week (Oct 11) and beyond

Highly dynamic week next week kicks off Mon with a NE/SW angled trough expected to form offshore from the top of the Hunter coast, or lower Mid North Coast. That will see strong S’ly quarter winds through Mon , possibly SSW to S and strong to low end gale force in strength. 

If you can deal with those winds, increasing short-range S to SSE swell is on the cards, with size expected to build into the 6ft range during the a’noon. Much smaller surf is expected in sheltered bays protected from S’ly winds.

The trough is expected to move north through Tues and form an elongated area of low pressure with a robust pressure gradient developing with a high moving East of Tasmania. That will see swell clock around through the SE to ESE as swell from the trough/low starts to fill in. Windspeeds aren’t expected to be anything over strong wind/low end gale and the fetch is quite mobile so size is expected to be constrained, at this point. Expect size in the 4-6ft range, easing through the day, with local winds also expected to lay down as the trough/low moves away and local pressure gradients slacken.

Still quite a few question marks over the second half of next week, with model divergence increasing between major weather models. We can make a call on local winds with a high degree of confidence as high pressure at Tasmanian latitudes drifts towards New Zealand, giving us an increasing N’ly flow off the back of the high. That sees N’ly winds freshen through Wed and Thurs with pressure gradients tightening as a complex, mid-latitude low approaches from the Bight.

Current wave model guidance is heavily discounting swell from the SE/ESE generated by the low as it drifts near the North Island, suggesting easing 3-4ft surf through Wed, with smaller 2ft surf on Thursday and NE windswell becoming the dominant swell train. 

It’s possible those figures may look better on Mon if E’ly winds near the North Island, or a lingering fetch of SE winds near the South Island over-achieve next week. GFS looks more bullish in that respect compared to the European model. 

By the end of the working week we are likely to be under the synoptic influence of the approaching low from the Bight, with winds expected to tend NW to W and freshen, especially if a cold front from the low impacts the region. 

This low is expected to enter the Tasman during the next weekend, with uncertain surf potential at this stage. Saturday is likely to see small surf, with easing levels of NE windswell and W’ly winds.

Sunday may see a late pulse of S swell depending on the timing and positioning of the low, but Monday looks a better bet for another round of S swell. 

Longer term and more S swell is expected from the week beginning 18/10, though with such a long lead time, plenty of revision is likely in the mean-time.

Have a great weekend and check back in Mon for a full update on the new week.