Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Monday 1st October)

Best Days: Tues: inconsistent long period S'ly swell and early light winds. Wed: inconsistent long period S'ly swell; winds should back to the NW throughout the day. Thurs: inconsistent long period S'ly swell, small E/NE swell and light winds. 

Recap: There wasn’t much surf on offer Saturday morning, with tiny leftovers and early W/SW winds ahead of a gusty southerly that kicked in around lunchtime. South facing beaches saw poor quality windswells build through the afternoon, holding into Sunday morning but easing from 3ft throughout the day, whilst early light winds gave way to an afternoon sea breeze. Today we’ve started off with small leftover swells, but as suggested in Friday’s notes we’ve seen new long period S’ly swell push through the coast this afternoon. At the time these notes were prepared, Sydney’s south facing beaches seemed to be in the 2ft+ range but our Newcastle surfcam is showing solid 4ft+ sets (unfortunately, being bumped up by a moderate NE breeze).

Solid Monday arvo sets at Newcastle

This week (Oct 2 - 5)

Today’s Forecaster Notes are brought to you by Rip Curl

By and large, there are very few revisions to be made for the next few days from Friday’s notes. The synoptics haven’t changed a lot and we’re still looking at a wide variety of swells from various flukey parts of our swell window(s).

As today has shown, this developing period of overlapping long period southerly swell is going to cause a lot of headaches on the forecasting bench. Whilst today generally came within forecast expectations (though admittedly confidence was low) there’s simply no way to be able to fine tune the mechanics of multiple swell trains from the same direction, especially from such a remote swell source where we often see large variations in size from beach to beach (and region to region) anyway.

Although I’m reluctant to do so, it’s hard to do much more than paint broad brushstrokes through this swell window for the next three days. Of which, it looks like we’ll see similarly sized swell tomorrow as per today (2-3ft south facing beaches with 4ft+ sets through the Hunter), easing slightly through Wednesday and early Thursday before ramping up much more significantly later Thursday and Friday with some very long period swell pushing 19-20 seconds - where we could see another couple of feet on top of the current energy. All of this energy will be sourced from an impressive conveyor belt of intense Southern Ocean fronts and lows.

In addition to offshore bombies and other reliable south swell magnets like the Hunter picking up bigger waves than regular south facing beaches in Sydney, it’s also worth pointing out that southerly groundswells will also arrive sooner across the South Coast. 

Local winds look light and variable early Tuesday but will freshen from the N/NE throughout the day, favouring protected northern corners. This northerly flow will continue into Wednesday but ease and veer NW throughout the day, offering an improvement - though the morning may still be wind affected. 

Small levels of NE windswell are expected in the water on Wednesday too, sourced from Tuesday’s developing local fetch.

The local synoptics then become much more complex from Thursday onwards, as a developing trough moving into our region looks like it may form a closed system - a Tasman Low, or possibly even an East Coast Low - off the South Coast during the day. This has massively complicated the surf outlook for the end of the week.

However, Thursday looks like it’ll see a period of light variable winds as the trough encroaches the region. What’s not clear is how this trough/low will develop, nor where - and this will have a major bearing on local winds (and the resulting local swell too). 

At this stage the models are throwing up some pretty large (and windy) estimates of short range south swell for Friday but I think we need a few more days to have any kind of confidence. And this all the more important, because irrespective of whatever develops in the Tasman Sea, we’ll also have a significant underlying long period S’ly groundswell. 

Oh yeah, and before I forget - the second half of the week will also see a small building E/NE swell, generated from a developing trough south of Fiji that looks pretty good on the MSLP charts but unfortunately won’t have quite enough strength to generate any meaningful size. A peak is expected over the weekend (with 3ft+ sets) but through Thursday and Friday we’ll see some smaller, inconsistent waves build across the coast underneath the long period S’ly groundswell - and whatever short range energy is whipped up locally on Friday.

This weekend (Oct 6 - 7)

It doesn’t get much more complex than what we have in front of us right now.

As a bare minimum the weekend will see small to moderate E/NE swell from the trough south of Fiji, some long period S’ly groundswell from the Southern Ocean progression, and then whatever local swell is generated by the system in the western Tasman Sea.

The latter will obviously have a strong bearing on surface quality too, so it’s simply too early to pin down any specifics.

However, there is almost zero chance of the surf being small this weekend.

Let’s fine tune things on Wednesday.

Next week (Oct 8 onwards)

There’s too much going on within the synoptic to paint any kind of picture for next week, at this stage. Things should become clearer by the end of the week.