Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Friday 29th May)

Best Days: Sat AM: small clean surf at the open beachie swell magnets. Wed onwards: large S'ly swells, though periods of windy conditions at times. 

Recap: SE swells have slowly eased from 3-4ft early Thursday to 2-3ft this morning and 2ft this afternoon. Winds have generally been light. 

Fun waves on the Cenny Coast today

This weekend (May 30 - 31)

Only small surf is expected this weekend. 

Saturday looks nice and clean with early light winds, though freshening NE breezes are expected after lunch (they’ll freshen N’ly for most of the day along the South Coast). We’ll see the wind veer N’ly overnight as a front approaches from the west, though a N/NW, maybe even NW tendency is possible through Sunday so some of the open beaches should clean up a little. But, expect some surface wobble at times.

As for swell, we’ve got a few peripheral sources.

Small E’ly fetches off New Zealand’s West Coast this week have generated minor energy that will occupy open beaches with 1-2ft sets. Small long period S’ly swell from migrating polar lows below the continent may provide slow, inconsistent sets of a similar size at south swell magnets, and Saturday evening’s developing N’ly fetch will generate some NE windswell, though this will show best south from the Illawarra on Sunday (just a foot or two north into Sydney and very little through the Hunter).

So on the balance, expect small options both days, and a few pockets of workable conditions, mainly in the mornings. 

Next week (June 1 onwards)

The remnants of the Tasman Low are now unlikely to develop into a useful swell generating system for the East Coast. 

Alhough the charts to show an impressive trough strengthening across New Zealand’s North Island on Sunday and Monday, only a small percentage of the fetch will extend into the Tasman Sea, and by the time the resulting swell arrives, it’ll be overshadowed by a much more prominent south swell. 

As such, we can safely erase that option from the forecast, though Monday should see small residual E'ly swells at open beaches in the 1-2ft range, with freshening NW winds. 

The new south swell looks pretty impressive event all up, and it will arrive in several stages, all associated with an amplifying node of the Long Wave Trough. 

Initially, strong southerly winds developing in the lee of a cold front (overnight Monday) will generate punchy local swells for Tuesday (3-4ft south facing beaches by the afternoon), but a second, stronger front racing up from the south will create a larger increase for Wednesday, with windy 4-6ft surf at south facing beaches. 

At the same time, a deep polar low will push NE from the ice shelf below Tasmania and up into the lower Tasman Sea (see below), with broad, gale to storm force S/SW winds encompassing a large region of NSW’s south swell window. We’ll then probably see the development of a large Tasman Low by Thursday morning. 

This should create large S’ly swells for Thursday and early Friday, somewhere in the 6-8ft range at south facing beaches. However we’re still quite a way out from this materialising, and it won’t take much of an upgrade in the strength and position of the Tasman Low to significant increase surf height estimates. 

Of course, such developments will be accompanied with periods of fresh, gusty winds out of the SW quadrant, but I’ll have more confidence on the timing of the best windows of opportunity in Monday’s update.

Either way, we’re looking at yet another strong, sizeable round of south swell next week, and there’ll be great surf persisting right through into next weekend too as wave heights gradually ease and local winds become light and favourable under the next ridge of high pressure. 

So don’t worry too much about this weekend, there’s a stack of swell on the way.

See you Monday!