Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 29th Nov)

Features of the Forecast (tl;dr)

• Window of favourable offshore winds likely Thurs with a morning peak in E/NE-NE swell, easing in the day
• Good winds again Fri with swell clocking around more E-E/SE
• Fun waves Sat with E/SE swell and light S’ly winds
• Mixed bag Sun (mostly SE swell) with freshening S’ly winds likely
• Small, fun S-SE swell likely early next week as low lingers in Tasman, S-SE winds Mon, tending N’ly Tues
• Troughy pattern continues
• Tracking the Solomons region for another potential tropical depression or TC, too early to determine any surf potential

Recap

Trashy onshore conditions for the most part yesterday but there was a reasonable amount of S swell in the water- around 3-4ft, a notch bigger on the Hunter. Onshore NE winds have freshened today as a complex inland low approaches with it’s associated troughs. We’re seeing building NE-E/NE swells from the infeed into this system, with size in the 3-4ft range. 

Stormy with building NE-E/NE swells as low pressure approaches South Coast

This week (Nov 29- Dec 1)

A dynamic weather event is underway as a complex inland low approaches the Far South Coast of NSW, expected to enter the Tasman Sea tomorrow. A moist NE-E/NE infeed into the low is generating plenty of rain (heaviest falls on the South Coast) and building swells from the same direction. A smaller trough with a similar but smaller NE infeed off the sub-tropical coast is now moving southwards. We’ll see improving conditions for Central/Southern NSW as the low moves offshore tomorrow. The low dissipates early in the weekend with remnants of the system captured by a front Sun and lingering in the Tasman Sea next week to supply small amounts of S to SE swell. 

In the short run as the low moves away o/night we’ll see a clearing offshore flow through the morning. Size will be limited by the fetch being shunted away during the same time period so get in early for clean 3-4ft+ sets, easing during the day.  There will be bigger surf available on the Illawarra and even bigger south of Jervis Bay down to the border. Offshore morning winds will tend variable then flukey/seabreeze in the a’noon.

Offshore W-SW winds Fri as the return flow from the low acquires a S’ly bias. Those winds will tend S’ly through the day, likely just after lunch in the Sydney region. A mix of NE swells and new S/SE-SE swell from the fetch off the bottom of the low should see wave heights build back up into the 3ft range during the day, bigger on the South Coast. Short range S swell will also be in the mix- a classic signature of multiple swell directions from winds feeding into the low.

This weekend (Dec 2-3)

S’ly winds extend over the weekend as remnants of the low pressure system stall out between Tasmania and New Zealand, with a weak S’ly flow through Sat. Morning should be clean and fun with W-SW winds and 3-4ft of surf from multiple sources. A broad infeed from the Northern Tasman, winds around the bottom of the low to name two Expect bigger surf on the Illawarra and South Coast. SE swells from the bottom of the low should be dominant but peaky surf should be widespread across the beachies with a weak onshore flow in the a’noon scuffing things up a bit.

Sunday sees the S’ly flow increase as a weak front and new high pressure ridge combine with the decaying low. Mod S’ly winds at the minimum are expected, likely tending fresh in the a’noon. Workable 2-3ft surf in the morning from the SE is likely to become wind affected in the a’noon with some new short range S-S/SE swell building to 2-3ft in the a’noon. 

Next week (Dec 4 onwards)

The reconstituted low looks to drift NE in the Tasman early next week with high pressure moving East of Tasmania Mon. A resultant SE fetch through the middle Tasman isn’t too strong as far as windspeeds go, but should see workable surf in the 2-3ft range Mon, likely extending  into Tues.

A S’ly flow Mon should tend variable then N’ly on Tues as another troughy area approaches Central NSW. We’ll revise that on Wed.

Further ahead and models are mixed with GFS suggesting a moderate frontal passage and a S swell later next week.

EC maintains a weak, troughy pattern from mid week onwards. Not much point putting confidence in either scenario with the instability of this current troughy regime. 

In the South Pacific the previously active area near the Solomons that has already spawned two tropical cyclones looks to flare up again next week with convective activity enhanced by a cross-equatorial flow. We may see a new tropical depression or even cyclone form later next week, with uncertain surf potential at this very early stage. There’s some model guidance that, at a minimum, we may see an enhanced trade flow in the Coral Sea later next week as the depression drifts southwards. 

Let’s see how it looks on Fri.