Sydney Hunter Illawarra Forecast by Steve Shearer (issued Mon May 27th)

Features of the Forecast (tl;dr)

• S-S/SE’ly groundswell easing Tues with light winds
• Small S swells Wed with N’ly winds
• Couple of quiet days at the back end of this week with small NE and S/SE swells
• Dynamic weekend ahead with front and potential trough forming off NSW S. Coast- low confidence in specifics but potentially large swells developing Sun or Mon
• Dynamic week next week as trough or low pressures in Tasman brings S swells and offshore winds- check back Wed for latest updates

Recap

Nice conditions over the weekend with morning offshores lingering into light/variable winds with afternoon glass offs. S swell pulses kept surf zones active with size to 2-3ft Sat morning, building to 4ft in the a’noon. Similar size on Sun. Today has built another notch into the 3-5ft range but the lines are very straight and closing out most beachies. Good to great surf if you have a reef or other swell shaping feature at your disposal.

Long-lined sets in the dawn mist

This week (May 27-31)

Lovely late autumn conditions as high pressure drifts across NSW bringing light winds and settled conditions through the first half of the week. A pair of weak cold fronts are expected to pass over Tasmania in the short term, generating small S swells which will overlap with the last pulses coming from the polar low now SE of New Zealand. A dynamic, troughy pattern looks set to unfold over the weekend. Read on for details.

In the short run we’ll see dreamy conditions continuing through tomorrow with light offshore winds for the morning, tending to light a’noon N-NE seabreezes. A mix of mid and longer period S swell trains should hold 3ft sets at S facing beaches, smaller elsewhere.

By Wed we’ll see high pressure in the Tasman and with an approaching inland trough and cut-off low in the Bight a N’ly flow will develop and freshen through the day. Early light winds from the W-NW will tend N’ly and freshen in the a’noon. Mostly mid period S swells to 2-3ft will be on offer, best at S facing beaches. 

Looks like a small blend of short period N-NE windswell and S/SE swell for Thurs from an off-axis fetch near New Zealand early this week. Similar winds as Wed with morning W-NW breezes tending mod/fresh N’ly in the a’noon.

Pre-frontal N’lies continue Fri with small NE windswell and some E/NE swell from the top of the high. At present the proximate fetch of N’ly winds looks poorly aligned so we’re unlikely to see more than 2 occ. 3ft of surf through Fri but we can update this if required during the week.

This weekend (June 1-2)

Interesting weekend ahead and it’s likely we’ll be revising further as we go through the week due to model divergence as they struggle to resolve a troughy/dynamic pattern.

A front passing over Tasmania is likely to bring a W’ly flow through Sat so conditions are looking groomed for the day. NE-E/NE swell from the top of the high, mixed with some small leftover S/SE swell should hold some fun 2-3ft surf through Sat.

Sun looks a different story. We mentioned on Fri a trough deepening off the QLD coast. Models are now favouring a trough moving off the NSW South Coast and deepening, possibly later Sat or into Sun and forming mutliple low centres (see below). Depending on the positioning of the trough and a potential surface low we could see a rapid increase in onshore winds and swell through Sun (ECMWF resolution) or offshore winds and small swells building later in the day or into Mon (GFS). Confidence in model outputs is low so check back Wed for updates. 

Next week (June 3 onwards)

Uncertain outlook due to the model divergence over the weekend. It’s likely we will see swell of some significance early next week as the trough or potential low drifts SE across the Tasman. These short range features look to dominate the Tasman early next week with the main southern storm track continuing to develop in the NZ corridor aimed at Pacific targets.

Models have been all over the place over the weekend and with such poor run to run and model to model consistency we’ll need to watch and wait for guidance into next week before we can have any reasonable confidence in the surf outlook.

Check back Wed and we’ll update with all the latest information.

Seeya then.