Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon 3rd Oct)

Forecast Summary (tl;dr)

• Nice pulse of ESE swell Mon with light winds, slowly easing through Tues with morning offshores
• Pulses of small S’ly groundswell from Wed-Fri this week
• Onshore flow develops Wed with short range E-E/NE swell tending to NE swell Thurs-Sun
• Plenty of E/NE tradewind swell Mon-Wed next week
• Uncertain wind outlook from Sat due to coastal trough and possible low, check back Wed for updates

Recap

Plenty of energy over the long weekend as a low drifted through the Tasman. Saturday was large and unruly with 5-6ft of surf, bigger 6-8ft on the Hunter and mod/fresh S-SSE winds confining surfing to the most protected corners. Sunday saw easing winds with a morning offshore breeze and 4-5ft of SSE-SE swell lighting up protected corners. Today has seen more light winds with strong SE-ESE swell filling in, in the 3-5ft range, a notch bigger on the Hunter. Great conditions before onshore winds kicked in. 

Plenty of size this morning with much lighter winds

This week (Oct 3-7)

Weak high pressure is now moving NE from Tasmania to cover the NSW Coast, leading to a couple of days of mored settled conditions. A much stronger high is moving into the classic La Niña slot- SE of Tasmania- where it will start to be squeezed by another approaching inland trough and complex low pressure system. That will see increasing NE winds come into play from mid-week with increasing levels of NE-E/NE windswell. Frontal progressions passing well to the south no longer have a strong surge into the Tasman but will send mid/long period pulses of S-SSE swell our way from mid week while a strong developing trade-wind flow will keep swell chugging away from the NE-E/NE into next week. A very active outlook for October. 

In the short run and we’ll be in mop-up mode tomorrow for the current pulse of E/SE swell which will be on the way down from this afternoon. Get in early for some 3ft leftover sets, clean under early NW winds before they tend to light E/NE to NE breezes. By the a’noon it’ll be slim picking with size dropping down to 2ft or so. Some traces of long period refracted S swell will add 2ft sets at S facing beaches, bigger on the Hunter.

Wednesday looks to be the low point of the week a blend of small S and residual ESE swell to 1-2ft through the morning, augmented by another pulse of small long period S swell adding some 2ft sets, bigger 2-3ft on the Hunter. A developing E’ly to E/NE’ly flow will add plenty of chop and bump for the a’noon session apart from the most S facing beaches and corners. 

By Thursday the stronger high will be dominant in the Tasman, located well to the SE of Tasmania and directing a fresh E-NE flow along the NSW Coasts with a proximate fetch extending out into the Tasman. We’ll see building levels of short range E-E/NE swell through Thurs, up into the 4ft range but messy under winds from the same direction. There’ll be some small mid period S swell in the mix but the signal will likely be too weak to be detected amongst the general onshore seas state. 

By Fri the approaching inland trough and cut-off low will be tightening pressure gradients with the high in the Tasman, with freshening N to NE flow along the coast. The biggest surf will be on the South Coast and Tasmania where they will benefit from the full length of the fetch but the f/cast region will still see surf build into the 3-4ft range during the day, albeit mostly short period NE windswell.  Once again in the mix will be some mid/long period S-SSE swell supplying inconsistent 2ft sets, possibly a notch bigger at well known S swell magnets. 

This weekend (Oct 8-9)

A trough line is expected to push up the South Coast Sat morning, likely stalling south of Jervis Bay. Depending on how it shakes out we should see lighter NW winds at a minimum, depending on how far north the trough makes it. We’ll still see plenty of NE swell in the water in the 3-4ft range, possibly kicking a notch into the a’noon, depending on how the fetch intensifies offshore. 

Sunday is a mystery bag at the moment. Depending on the position of the trough line, we could even see a small low form off the Central or Southern NSW Coast with fresh S to SE winds through the region. If the trough stays south we will see continuing N’ly winds. The N’ly fetch infeeding into this system maintains plenty of NE swell, likely in the 4-6ft range, so it’s a question if winds will co-operate. Check back Mon and we’ll have fresh updates.

Next week (Oct 10 onwards)

We’ll see plenty of E/NE tradewind style swell through the opening days of next week. The tradewind fetch is broad and extends well down into the Tasman (see below), ensuring a good coverage of swell for the Eastern Seaboard next week. 

We should see an offshore flow through Mon as a small low forms in the trough line over the weekend and moves south. Size in the 3-5ft range, extending into Tues, with an uncertain wind outlook.

E/NE swell extends into Wed, possibly with some small S swell in the mix depending on the movement of the low. 

The tradewind fetch does break down early next week, with a tropical low forming and tracking away to the ESE, likely not generating much significant swell for the region under current modelling.

Models continue to show a lot of variability at present due to the increased troughiness and instability leading to low confidence in anything beyond the short term so check back in Wed for the latest update.