Sydney Hunter Illawarra Surf Forecast by Ben Matson (issued Wed 16th Aug)

Features of the Forecast (tl;dr)

• Easing S'ly swells from Thurs, tiny by Fri
• Small NE windswell early Thurs
• Tricky mix of south swells Sat AM, leveling out PM and into Sun, good winds
• Small leftovers Mon/Tues
• Another S'ly swell Wed

Recap

Strong S’ly swell on Tuesday, around 3-4ft at most beaches but with bigger sets at some spots (mainly Northern Beaches). Light W’ly winds through the morning before moderate to fresh southerlies kicked in just before lunchtime. Size has eased back a smidge today and conditions are nice and clean with light offshore winds.

Not quite a pot of gold in Newy this morning, but still, it's purdy

This week (Aug 17-18)

Easing swells are expected for the rest of the week, perhaps 2-3ft at south facing beaches early Thursday but trending down through the day and into Friday, which will be a slow, lacklustre day of surf. 

Early Thursday may see some minor leftover NE windswell from northerlies that are expected to crop up overnight, but at this stage I can’t see a lot of size potential, even NE swell magnets will be pretty small. 

Model guidance has a tiny south swell glancing the coast on Friday, originating from strong frontal activity below the continent, but at this stage I can’t see it amounting to much size either. 

The good news is that conditions are looking pretty good all round, with overnight N’ly winds (tonight) swinging NW Thursday morning, and then becoming fresh from the west through Friday as a vigorous frontal passage crosses the SE corner of the country.  As such the best window of waves looks to be mid-late morning Thursday once the wind’s swung offshore, but before the tail end of the south swell disappears completely.

Bear in mind, this window of opportunity will be fleeting.

This weekend (Aug 19-20)

A strong frontal progression pushing into the Tasman Sea late Friday will set up a decent SW flow exiting eastern Bass Strait. 

Although this change looks respectable on paper - we’ll see fresh SW winds extending as far north as New Caledonia by early Sunday (see below) - the synoptic flow will be disjointed through the lower Tasman Sea and into the Southern Ocean, which will limit its swell generating potential for Southern NSW.

So, instead of being a punchy round of south swell, it'll be a mixed swell with variable results, especially along the South Coast (which will be partially shadowed from the primary fetrch, compared to locations further north).

However, the upside is that local conditions will be clean all weekend with generally light to moderate offshore winds, maybe a weak afternoon sea breeze on Sunday.

As for size, most of the weekend will see an undercurrent of peaky south swell in the 3ft range at south facing beaches, a little bigger on the Hunter (4ft) but much smaller at other locations not open to the south.

The exception here will be sometime early-mid morning Saturday, should should see a brief round of bigger surf associated with the initial front transiting the Tasman Sea overnight Friday. This could deliver a few hours of 3-5ft sets at south facing beaches. But, some exposed spots may concurrently experience lumpy side shore conditions associated with gusty SW winds in the wake of the front (locally, early hours of Sat morning). So keep your expectations low at south swell magnets.

Next week (Aug 21 onwards)

The weekend’s broadscale frontal progression will slow near New Zealand and form a cut off low by Monday. Early indications are that it’ll probably remain aligned outside of our swell window, but we’ll keep an eye on it for next week’s surf potential. 

Otherwise, the next round of surf for the region looks to originate from another front exiting eastern Bass Strait around Tuesday night (i.e. producing a short range S’ly swell for Wednesday). This front looks to be tied in with a powerful but poorly aligned Southern Ocean low that - as a minimum - should continue to supply small long period southerly swell through the back half of next week. 

However, no major swells are otherwise showing on the radar.

See you Friday!