Sydney Hunter Illawarra Forecast by Steve Shearer (issued Wed July 16th)

Features of the Forecast (tl;dr)

• Small background conditions Thurs
• S'ly winds developing Fri, building short range swell later and poss a flukey long range S'ly swell too
• Generally light winds for the weekend with small flukey long range S'ly swells
• Mix of E/NE and NE swells through most of next week 
• Possibility of juicier E swell medium term as low intensifies in South Pacific next week- check back Fri for latest updates

Recap

A fresh pulse of S’ly swell supplied some tasty waves at spots open to that swell direction with size generally in the 3ft range, a notch bigger on the Hunter (4ft+ sets occ.) with a favourable offshore breeze tending NW through the day.  Size has come down just a smidge today with sets still in the 3ft range but we are on the backside of this pulse so we’ll see further easing through the day. Conditions should stay clean through the day under a light offshore flow tending to variable breezes this a’noon.

Some fun waves about as this current S swell eases off

This week (July 15 - 18)

All the action is under the continent at the moment with strong frontal activity generating plenty of swell for the southern states. The Tasman Sea is under the sway of weak pressure gradients as a decaying high pressure system sits off the NSW coast and a trough moves offshore from the Far South Coast. Another trough through the NENSW interior is expected to move offshore Fri and form a weak surface low. Not much short term gain from this system but there is broad model agreement we’ll see this low deepen and develop into a more powerful system mid/late next week as it drifts into a position north of the North Island. Best case scenario is a quality E’ly groundswell event from this system. In the interim we’re looking at mostly flukey swell sources to supply a rideable wave. 

In the short run we’ll see beautiful conditions tomorrow but only small leftovers from the S. Magnets should still be hoovering up a few 2ft sets with tiny surf elsewhere. Light winds all day, tending to W/SW winds as the small low forms off the coast will make for A-grade conditions so its worth having a squizz at magnets to see if they are offering up some shape.

We’ll see conditions deteriorate Fri as the trough deepens into a low with early W-SW winds shifting S then S/SE at mod paces. Only tiny surf to start with some short range S-S/SE swell filling in to the 2ft range during the a’noon. As mentioned on Mon, we may see some super flukey long range S swell from the edge our swell window but it’s hard to see anything much more than a grovel on offer through Fri under a developing onshore flow. In the event winds do look better for Fri it’ll be worth keeping an eye on S magnets.

This weekend (July 19 - 20)

Winds still look good for the weekend with offshore winds both mornings, tending N-NE on Sat, light and variable Sun. We may still need to tweak that on Fri as a troughy area hangs around the NSW Central/South coast.

Generally it’s a low energy weekend with some flukey swell sources on tap and a weak low in the Tasman expected to offer some shorter period swell into the mix. Keep expectations low though, nothing more than 2 occ. 3ft is expected as a maximum.

Long range S’ly swell is showing on wave models and with significant swell periods is worth looking at S swell magnets.

The system E/SE of the South Island looks even less well aligned for swell production for NSW but a very occ. 2ft set from the SE can’t be ruled out. All in all, there should be enough energy from these various swell sources to find a rideable wave both days. 

Next week (July 21 onwards)

Eyes to the east next week as low pressure sits in the Tasman. Expect revisions over wind as get into the nitty gritty next week but the basic outline of a broad low forming in the Northern Tasman has medium confidence attached to it. High pressure moves into Tasman bringing E then NE’ly winds from Mon into Tues. We’ll likely see some small E/NE-NE’ly swell start to develop through the same period, provisionally in the 2ft range Mon, 2-3ft Tues. 

There should be enough fetch length off the top of the high through next week to maintain that level of swell energy but we’ll fine-tune that on Fri.

The big question will be the next incarnation of the low as it drifts N-NE of the North island into Fijian longitudes and intensifies. Current modelling suggests a sufficient intensification and slowing of eastwards movement to generate a significant E’ly swell favouring the sub-tropics for size. 

We’d expect an initial downward trend into next weekend and if the situation plays out favourably an increase in E swell possibly as early as Sun int the sub-tropics, early week 28/7 into temperate NSW with potential for size in the 5-6ft range in the sub-tropics, 4-5ft further south. Those are low confidence numbers so expect adjustments either up (hopefully) or downwards as we get more model guidance. 

Still a long way off, so we’ll see how it looks on Fri.

Seeya then.