Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 23rd June)

Best Days: Thurs/Fri: small clean waves at open beaches early. Late Sun: small new south swell

Recap: Easing E/SE and S’ly swell on Tuesday with generally clean conditions. A new S/SE swell arrived this morning and has pushed just above forecast expectations (2-3ft Sydney, 3-4ft Hunter), and conditions have been generally good with light winds.

This week (July 24-25)

Today’s S/SE swell should just hold through into Thursday morning but is expected to trend downwards during the day. We’ll see the biggest waves across open beaches in the Hunter (inconsistent 3ft+ sets at dawn), with smaller surf in Sydney (2ft, occ 3ft south facing beaches) and smaller again on the South Coast - but expect a distinct drop in size from early-mid morning onwards. Winds will freshen from the NW in the morning before tending N/NE in the afternoon so aim for an early session.

On Friday, we’ll see a new small long period south swell fill in underneath the almost-gone S/SE swell from today. Unfortunately ASCAT data didn’t show much spatial coverage of the polar low responsible for this incoming swell (well south of Tasmania Tuesday) however winds were recorded in the 40kt range. As such I’m lowering my expectations to a couple of stray 2ft sets in Sydney (but generally smaller than this, especially at beaches not open to the south).

It’s possible that the Hunter will pick up more size from this source - say, occasional 2-3ft sets at times - but I wouldn’t bank on it, as this swell will have originated from a very large distance away and there’ll be lengthy breaks between bigger waves.

Likely to be a little more prominent in the water on Friday is a small NE windswell generated by Thursday afternoon’s locally freshening winds. At this stage I think we’ll be lucky to see much more than a couple of feet on offer at NE facing beaches but hopefully the combination of the south and north-east energy will provide some peaky options at open stretches. Winds will be initial moderate NW but are also likely to trend N/NE into the afternoon, so aim for the morning session for the best conditions.

This weekend (July 26-27)

Nothing great is expected this weekend surf-wise: we’re looking at a small peaky combo of NE windswell and inconsistent long range S'ly groundswell. Winds will freshen from the west on Saturday as a trough crosses the coast and into the Tasman Sea but I wouldn’t expect much more than a foot or two of low quality surf at exposed beaches. 

As the trough moves further out into the Tasman Sea on Saturday, a broad SW fetch will develop along its western flank and should kick up a short range south swell for Sunday, probably arriving around lunchtime, give or take a few hours. This size increase will only be seen at south facing beaches - and probably only north of about Jervis Bay, due to the fetch's position right off the South Coast.

There’s currently a lot of divergence in the models around the strength and alignment of the fetch, and consequently the surf forecast isn't particularly confident right now. However I’m going for an afternoon increase into the 2-3ft range at exposed south facing beaches; I’ll pin this down a little better in Friday’s update.

Longer term (July 28 onwards)

No major changes for the long term forecast. An amplifying node of the Long Wave Trough SW of West Oz will slowly move below the continent over the coming week (generating a lengthy round of large windy waves for the southern states), but its position will essentially steer all major swell generating activity away from NSW's southern swell window. 

This suggests an extended period of small conditions for the East Coast, interspersed by short lived events from flukey parts of our swell window.

Current thinking is that a vigorous frontal passage across Bass Strait mid-next week will spawn a short range south swell around Thursday or Friday, with follow up south swells of a similar nature the following weekend - but it’s still very early days. I’ll take a closer look on Friday.