Sydney Hunter Illawarra Forecast by Steve Shearer (issued Wed April 24th)

Features of the Forecast (tl;dr)

• Minor background E/NE swell Thurs-Fri offering up the occ. 2ft set, persisting into the weekend at minor levels
• S’ly winds Thurs with an increase in raggedy S swell
• Solid S swell improves a little Fri as winds ease
• Clean conditions Sat with quality S swell on offer
• Easing surf Sun with light winds
• Small to start next week
• More S swell on offer from Tues next week but S’ly winds remain persistent

Recap

S swell yesterday came in nice and “warm” at the top end of f/cast expectations or just above with a nice spread of 2-3ft surf at S exposed breaks, bigger on the Hunter with clean conditions for most of the day. That source has eased into today with minor 1-2ft surf on offer, clean early before a S’ly change after lunch, generated by a tight trough of low pressure now moving NE fro Tasmania. 

Lovely clean conditions yesterday with fun S swell

This week (Apr 24-26)

The sharp trough in low pressure moving NE of Tasmania is generating a fetch of gales tracking through the southern swell window, with a following long, broad fetch of S’ly biased winds moving NE through tomorrow, setting up a series of S pulses in the run up to and over the weekend. A weakening trough of low pressure near New Caledonia is seeing easing E swells across the sub-tropics. A monster high (1037hPa) moves into the Bight tomorrow and slowly weakens as it enters the Tasman on the weekend, bringing light winds from temperate NSW right up into the sub-tropics.

In the short run, todays gale force fetch pushing NE of Tasman generates a pulse of S swell for tomorrow, but mod/fresh S’ly winds will hamper wave quality. Expect mid period S swell to 3-4ft at S exposed breaks, smaller into more sheltered bays. There will be some up and down as various swell trains make landfall with another pulse likely in the a’noon, still hampered by S’ly winds.

Friday looks solid as a range of mid period and longer period S swell trains generated by the proximate and deep fetches make landfall. Unfortunately the new high pressure ridge will reinforce the S’ly flow along the coast but we should see a morning SW breeze before that happens. Expect 4-5ft surf, at least at S exposed breaks, bigger 6ft on the Hunter, and smaller into more sheltered spots. Mod/fresh S’ly winds should ease back a notch in the a’noon as the ridge relaxes quite quickly. The weekend will be cleaner if you want to wait for better conditions.

This weekend (April 27-28)

Still looking good for the weekend, especially Sat as high pressure moves across Southern NSW and light winds establish. We should see light land breezes both days, with a slight S’ly bias Sat (W/SW-SW) and more true W’ly Sun, with a’noon E’ly breezes Sat, tending NE on Sun.

Sat still has plenty of leftover S swell, a mix of mid and longer period stuff with sets still in the 4 occ. 5ft range but easing through the day. 

By Sun we’ll see much less energy in the water, offering inconsistent 3ft sets at S facing beaches, dropping back to 2ft or less through the day.

Both days will see traces of E/NE swell but it’s not likely to be a useful swell source, just the odd 1 to occ. 2ft set.

Next week (April 29 onwards)

Light winds to start next week, as a high pressure sits in the Tasman. An approaching front/trough system is likely to see NW possibly pre-frontal N’ly flow through the day. Not much swell expected though, just some minor leftover S and background E swell which will offer up just surfable options on the beachies (1 occ. 2ft). 

A low pressure system forming N of the North Island looks to quickly duck behind the shadow of that swell blocking Island but we’ll keep an eye on it and update Fri.

The front and trough looks to bring a robust S’ly change Tues with an increase in mostly short range S swell. If the trough deepens we may see an even bigger increase in S/SE swell through Tues a’noon into Wed. We’ll revise that on Fri but it looks windy and ragged as a minimum at this stage.

Windy S-S/SE swells continue into Wed as another major high well south of the Bight shifts E and a series of fronts sweeps across the lower Tasman. That should see moderate to sizey S swells through the second half of next week with an onshore S-SE flow due to the southwards positioning of the dominant high pressure ridge. We’ll keep eyes on the charts for any possibility of a trough deepening into a low pressure system in the Tasman but at this stage there’s nothing concrete to report on.

Check back Fri for the latest updates.