Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Nov 1 )

Forecast Summary (tl;dr)

• Few small leftover sets from the S Tues morning at S facing beaches
• NE windswell at low levels Tues, holding at small/marginal levels through Wed/Thurs
• Small, flukey S swell pulse Wed at S facing magnets
• Juicy ESE swell building Fri, holding Sat morning, with continuing NE winds

Recap

A compact but storm force low which formed east of Tasmania on Friday has bought several pulses of S swell over the weekend and extending into today. Saturday was a bit undersized according to f/cast expectations at some places, which saw only 2-3ft surf, but bigger surf was reported at S facing beaches in Sydney. Stronger, longer period surf filled in through Sunday with 5-6ft surf on the Hunter, 3-5ft at S facing beaches elsewhere. Winds from the south moderated in strength and tended to light NE breezes in the a’noon. Strong S swell held into this morning with some 5-6ft sets on the Hunter, smaller 3-4ft in Sydney, and conditions were clean-ish with a light N’ly flow, which is now beginning to freshen and tend NE. All in all, there were a few windows despite generally tricky winds to work around and a swell that was a bit too long and straight for most beachies.

This week (Nov1-5)

The robust low responsible for the current S swell event has now fled the Tasman sea, so we are relying on residual swell which is now on the downslope. A large (1025 hPa) high pressure system is currently drifting over Central NSW into the Tasman sea and this high pressure cell is expected to track SE, strengthen and  become slow moving as it meanders near the South Island for most of this week. That creates a summer-style synoptic pattern, with SE/ESE Tradewinds through the sub-tropics and a N’ly flow through temperate NSW. A low pressure system developing north of New Zealand’s North Island drifts south to be over the North Island Wed, and while that blocks most of the fetch from generating swell for the East Coast, it does shoot out a fetch through Cook Strait Wed/Thurs which looks like a tidy source of ESE swell for the region Fri/Sat. More details below.

Looking short term and the blocking pattern will be established, resulting in NE winds through to the weekend. It’s quite a weak, gradient wind so keep expectations pegged very low for NE windswell- 1-2ft at best, and biggest during the late a’noon when wind strengths are at their diurnal peak.

Small amounts of leftover S swell through Tues will be worth some 2ft sets, possibly 2-3ft on the Hunter, but that will fade away through the day, with small NE windswell becoming the dominant swell train.

Not much to recommend Wed, as mod/fresh NE winds continue. As we mentioned Fri, a broad polar low is passing during Mon, but the fetch is aimed mostly at targets to the East of New Zealand and thus we are only looking at minor sideband energy heading up the Tasman Sea. That could be worth some stray 2ft sets on Wed, possibly 2-3ft at some of the more reliable S swell magnets, but it’s a very flukey source so don’t burn fuel chasing it.

Thursday maintains small NE windswell, with possibly some stray leftover S swell trains at more reliable S facing magnets. Nothing much to get frothed about.

The end of the working week is expected to see a marked increase in swell, from the Cook Strait fetch we mentioned earlier. Under current modelling this gale to severe gale force fetch elongates out of Cook Strait, adjacent to the Taranaki peninsula and retrograding  into the Tasman Sea Wed, and into Thursday. 

This looks great for a pulse of ESE groundswell arriving Fri, building during the day from an under-sized 2-3ft into the 3-5ft range. You’ll have to work with the continuing NE wind, but if you can solve that problem there should be plenty of good surf through Fri a’noon to wind down the week. 

This weekend (Nov 6-7)

Plenty of ESE swell through Sat morning from the Cook Strait source, with size likely to peak in the 4-5ft range through the morning, before size rolls off in the a’noon. Winds are a bit of a concern. The movement of the retrograding fetch through the end of the week, sees the gradient wind tend a bit more to the ENE through Sat, though it’s likely to be lighter and possibly NW inshore early morning. Winds will be better through the morning, any way we slice it.

Sunday will be mopping up the leftovers of the ESE swell, with reduced energy in the 3ft range, declining through the day. The block pattern will be starting to shift as an inland trough approaches, likely seeing winds from the N to NNE freshen during the day. Again, winds will be best early before they crank up, likely being enhanced by a’noon Seabreeze effects.

Next week (Nov8) and beyond

Into next week and models are struggling to resolve the troughy pattern as it enters the Tasman Sea. The northerly pattern is likely to extend into Mon, with small NE windswell on the menu.

A troughy, S’ly change is likely Tuesday next week, and although there’s considerable model divergence which lends extremely low confidence in the specifics, a new S swell is likely through Tues/Wed next week. No great size expected at this stage. 

Check back Wed for a fresh update.