Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 20th Sep)

Features of the Forecast (tl;dr)

• Small amounts of E/NE swell filtering down from tradewinds provide a small, background signal through the week and into the weekend
• S’ly change Wed night with fresh S’lies Thurs and building short range S swell
• Mix off S’ly swells Fri with easing S-SE winds
• Small mixed bag Sat with an a’noon kick in new S swell
• Better quality S swell persists Sun with good winds
• Small E/NE swells continue next week bumping up a notch Tues/Wed
• Small mixed bag of swell sources into the medium term

Recap

Really fun combination swell yesterday with a mix of E/NE swell (dominant across the Illawarra) and some long-lined S’ly groundswell (dominant across the Hunter/Central Coast). E/NE swell was in the 3ft+ range and S’ly groundswell was mostly 3-4ft with some occ. bigger sets touching 5ft, all under offshore NW winds for most of the day. Lefts runners, right walls and some quality A-frames were on offer across the region. S’ly swell has eased back today with E/NE swell becoming dominant, holding in the 2-3ft range. Conditions were clean early under W-NW winds with a late S’ly change expected to cool things down after an extended hot spell. Thankfully, with some good waves for aquatic relief.

Back to peaky NE-E/NE today as S'ly groundswell drops out of the mix

This week (Sep20-22)

High pressure is now close to New Zealand, with an advancing trough and cold front bringing a fresh S’ly change, expected to generate a strong SE surge up the sub-tropical coast as a new high moves into the Bight and strengthens. Once the high moves into the Tasman over the weekend it’ll set up a blocking pattern but we’re expecting a few small S pulses leading up to that although winds look fickle. E'ly swell from persistent tradewind fetches should continue as a fun background source of swell. There should be a few small swell sources to work with next week. 

In the short run and S’ly winds tomorrow will constrain clean waves to sheltered corners and bays but there’ll be some 2-3ft NE windswell and E/NE swell to work with. Expect a morning SW flow north of the Harbour before mod/fresh S’lies kick in (early S’lies on the Hunter). A kick in new short range S swell to 3ft at S facing beaches will be low quality stuff and only for the very keen.

Not much of an improvement in conditions for Fri- that S’ly flow will hang in there and tend SE through the a’noon. A morning SW flow will be brief and limited to the usual spots north of the Harbour. E/NE swell from a very persistent fetch should hold some 2ft surf, making protected corners and Bays worth a look. Short range S’ly swells in the 3-4ft range will add some energy to that mix, easing during the day. It does offer up some potential A-frames although nothing like what we’ve seen earlier this week. There’ll be more size on the Hunter but the S’ly flow won’t do much for surf quality. 

This weekend (Sep 23-24)

Winds back down this weekend as high pressure drifts over Southern NSW so we should see light land breezes for both mornings with Sat seeing a light SE-NE a’noon breeze and winds tending more N-NE on Sunday. Typical spring progression.

Small amounts of E/NE swell hang in there in the 2ft range and with S-S/SE swell of a similar size (2-3ft on the Hunter) there should be a few workable beachies on hand for Sat. An a’noon kick in better quality S swell to 3ft is also on the cards from a weakening front/low Thurs.

That pulse should hang in for Sun morning before easing, with small amounts of E/NE swell ticking away in the background. All up a few 2 occ 3ft sets on offer with good S swell magnets topping out the size and enjoying the N’ly winds expected.

Next week (Sep 25 onwards)

Small mixed bag continues into next week with the basic building block of a slow moving high in the Tasman and N'ly winds to kick off the week. Nothing major expected for Mon, just a continuation of small S and E swells topping out at 2ft on open beaches.

We may see a trough Tues with flukey winds. E/NE swell should bump a notch as an angular trough which runs right up the South Pacific swell window focuses tradewinds into a more E/NE alignment over the weekend. That should see swell bump up a notch from the E/NE Tues into Wed. 

Models are divergent about the possibility of a trough forming off the NSW Coast later next week, pssobioy a source of local S swell if it forms according to the EC model. GFS suggests a low/front passing up towards New Zealand Tues with small/moderate S-S/SE swell Thurs.

We’ll see how all this shakes out on Fri but odds are good we’ll have enough mixed swell sources to keep the wave count ticking over.

Check back Fri for the latest.