Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Friday 17th August)

Best Days: Sat AM: offshore with a fun S'ly swell early morning. Sun: windy but building S'ly swells during the day (small early). Mon: very large from the south, but very windy. Tues: very large from the south, but easing, with light winds. Wed/Thurs: easing S'ly swell, light winds. 

Recap: Thursday delivered small, inconsistent waves for most of the day however a new south swell kicked in late, providing inconsistent 2-3ft sets in the hour or two before dark. This south swell has pulsed intermittently today in and around the 3ft range across Sydney’s south facing beaches, whilst exposed Hunter beaches have seen bigger waves around 3-5ft. Winds have been generally favourable with light winds. 

Small clean southerly groundswell lines at Manly this morning

This weekend (Aug 18 - 19)

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

Today’s south swell is now easing, but a fresh pulse of south swell will fill in overnight, generated by the parent low to the front that kicked up today’s swell.

This low was positioned S/SE of Tasmania on Thursday, and didn’t hang within our swell window for very long, so the resulting swell will last only a short period of time. And unfortunately, some of this will occur under the cover of darkness (tonight).

Therefore, you’ll have to make the most of Saturday morning as it’s when we’ll see the most size. Most south facing beaches should pick up 2ft, almost 2-3ft sets with bigger waves around 3-4ft, maybe 3-5ft across the Hunter. However as per usual, beaches not exposed to the south will be much smaller. Expect smaller waves to prevail throughout the day as this event slowly eases in size. 

Conditions will be clean with freshening NW winds ahead of a late gusty W’ly change. 

This change will be associated with a series of vigorous fronts crossing the SE corner of the country, and they’ll deliver cold conditions to the region and maintaining fresh to strong W/SW winds, that’ll veer SW at some point into the afternoon. 

Although a deep Tasman Low will begin developing east of Tasmania through Sunday, the initial fetch alignment within our swell window will be very west so Sunday’s surf will consist of small leftovers from Saturday, plus slowly building S’ly swell from the SW/SW fetch exiting eastern Bass Strait - probably building to 3ft+ into the afternoon at south swell magnets (much smaller earlier). Surf size will remain very small at locations not open to the south. 

However, early-mid Sunday afternoon is expected to see a small embedded low strengthen off the South Coast and this could deliver a strong, though very late round of short range south swell in the few hours before sunset (however it’ll ultimately peak through Monday). Any late increase will be accompanied by strong SW winds so conditions won’t be great but keep an eye on conditions as there's a chance for pockets of opportunity. 

Next week (Aug 20 onwards)

We’ve got a complex series of large south swells for the first half of next week. They’ll originate from a deep Tasman Low that’s expected to display several embedded low/fronts wrapping around its western flank, all of which will be working on a large pre-existing sea state. 

Our surf model seems to be handling this event pretty well, though the take home message is that Monday will be very wind affected with strong to gale force SW tending S’ly winds as the low pushes close to the coast. There’s a slim chance for a brief period of early W/SW winds but if this occurs it’ll be confined to a handful of coasts like the Northern Beaches. 

As for size, Monday will see a broad mix of southerly swells contributing size up into the 6-8ft+ range at south facing beaches (bigger through the Hunter). Protected spots will be your only choice. 

Late afternoon will see a large pulse of slightly longer period S’ly swell pushing through, which could see some much bigger waves in the last few hours of the day (see chart below, from our Northern Beaches data point). This next round of energy will be sourced from a secondary embedded low positioned much further south in the Tasman Sea, which will allow for a better quality groundswell to develop (especially because it will have been working on an active pre-existing sea state), and with the local fetch off the South Coast also easing later Monday, the short range southerly energy will ease back in size through Tuesday. 

Even better, the low will clear to the east and this will allow offshore W’ly winds to brush the ocean clean. Sets should push the 8ft+ mark at south facing beaches, though offshore reefs and bombies well aligned to the south could see much bigger waves, depending on how well they can focus and magnify the energy. However once again, locations not directly open to the south will see smaller surf, and wave heights will trend down throughout the day. 

You'll be best off aiming for sheltered spots once again on Tuesday - but keep mind there'll be a lot of water moving around, so make sure you're confident in your ability before paddling out.

Light winds are expected for the rest of the week under a broad but relatively benign high pressure system. Tuesday’s very large southerly groundswell will abate through Wednesday, from 4-6ft to 3-4ft at south facing beaches throughout the day (bigger in the Hunter though smaller elsewhere).

Expect size to continue down through Thursday, bottoming out into Friday aead of a small bump of long period Southern Ocean S’ly groundswell on Saturday that’ll renew surfable options across south swell magnets. 

More on that in Monday’s update. Have a great weekend!