Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Friday 24th April)

Best Days: Sat/Sun AM: fun small E'ly swell with offshore winds. Bigger south of Sydney. Sun: late increase in (windy) short range south swell. Wed/Thurs: Easing S/SE swell with generally light winds.

Recap: Pumping beach breaks for the last few days. Leftover but easing 4-5ft SE swell on Thursday morning was replaced by a new E’ly swell into the afternoon, with 3ft sets at open beaches. This size range has persisted through today with great waves on offer at most beaches (and bigger 3-5ft surf at exposed spots on the South Coast, owing to a better aligned fetch). Conditions have been generally clean with light offshore winds. 

This weekend (Apr 25 - 26)

Wave models have a minor reinforcement of E’ly swell due early Saturday morning, extending from the same fetch that produced today’s waves - essentially, an infeed of NE winds into the broad but slowly weakening Tasman trough.

I am a little concerned that the trough is located a little too far away form the mainland, and that the fetch is more perpendicular than parallel to the swell window, to deliver any great size to the Sydney coast. However, as per today we’ll see larger surf with increasing southerly latitude, so it’s well worth a trip down south if you’re that way inclined.

As such, I’m going to hold steady with my original forecast for 2-3ft surf across most open Sydney beaches on Saturday. Set waves will be a little inconsistent at times but it’ll be clean with light offshore winds for the most part (a shallow sea breeze is possible mid-afternoon).

Surf size will be bigger further south, probably 3-4ft across much of the Illawarra region and 3-5ft south from about Jervis Bay (but equally inconsistent). However, we will probably see slightly smaller surf (than Sydney) up in the Hunter region. All in all, there should be a healthy smattering of fun peaky waves at most beach breaks.

On Sunday, I'm expecting a combination of east swells in the water - initially some leftover energy from Saturday plus a new E/NE pulse from a tropical system that developed NE of New Zealand during the middle of the week. This should maintain a similar size as per Saturday however set waves will probably be even less consistent owing to the more distant swell source. Local winds are expected to strengthen with an approaching frontal system though - they will be offshore (west tending south-west) but it’ll become blustery at times. 

In Monday’s notes I mentioned a developing Tasman Low off the South Coast during Sunday that would generate a solid late kick in new southerly swell. By Wednesday, the models had delayed the development cycle of this low, but in the last few model runs they’ve shunted it forward again - so much so that the latest guidance has a 40kt+ fetch off the South Coast developing from mid-late morning onwards.

What this does to the surf outlook for Sunday is increase the chances that we’ll see an appreciable kick in short range southerly swell.  There’s also a risk in this synoptic pattern that winds may veer more S/SW through the latter part of the day (in sync with the building swell) so I’ll keep an eye on things and update in the comments below accordingly. But right now there's the potential for an increase towards 3-5ft at exposed south facing beaches from mid-late afternoon onwards (smaller at remaining beaches due to the swell direction). It’ll be bumpy and windy but it’ll certainly be an alternate option to the morning’s clean but inconsistent E’ly swell.

Next week (Apr 27 onwards)

Although this Tasman Low is expected to track steadily east away from the mainland from Monday onwards, a strong high in the Bight will direct a vigorous southerly airstream across the Southern NSW coast for the first few days of the new week. 

This should maintain somewhere around 4-5ft+ of average short range swell at south facing beaches, with smaller 3ft waves at remaining beaches and very small surf inside protected southern corners. There’ll also be some distant E’ly swell in the mix at most open beaches, but it’ll be very inconsistent, just a couple of feet at best.

Local winds may veer W/SW across a few coasts for brief period in the early mornings (Mon/Tues) but in general we’re looking at fresh S/SW tending S’ly winds. So, keep your expectations low. 

From Wednesday onwards, we’ll see easing swells form the southern quadrant as a high pressure system fills into the souther Tasman Sea and the swell window dries. up. There should still be plenty of good waves at open beaches though, both Wednesday and Thursday. 

As for the long term outlook, We’ve got a strengthening ridge across the Northern Tasman Sea and a developing coastal (and secondary inland) trough along the East Coast later int he week that has potential to prime the atmosphere for a significant weather (and swell) event sometime around next weekend. More on this in Monday’s update.