Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon 21st Aug)

Features of the Forecast (tl;dr)

• Small S leftovers Tues- low point in energy
• Modest S'ly swell Wed with winds tending S-SE in the a’noon
• Small long period S swells mid/late this week
• Poor quality S swell Thurs AM with lingering S’ly winds
• Tricky outlook for the weekend with low pressure trough possible off NSW Coast
• Likely freshening S-SE winds this weekend with building SE swells
• Plenty of SE swell likely early next week with winds slowly moderating 
• Potential for several E’ly swell sources next week- check back Wed for updates

Recap

Pulses of S swell over the weekend provided enough energy for fun surf at S exposed breaks. Surf pulsed in the 3-4ft range both days with mostly clean conditions. Still some clean surf on offer today in the 3-4ft range with clean morning conditions under offshore winds, which are expected to tend mod N/NE through the day. 

Nice energy still on offer this morning with an easing trend

This week (Aug 21-25)

The Tasman Sea is looking very benign to start the week with a large area of weak high pressure over the Eastern Seaboard and extending into the Tasman. The remnants of the weekends frontal systems have set up a fading off axis fetch near New Zealand with the current run of small S swells also on the way out. A weak mid week front will bring a wind change and a small flush of S swell but next week looks a bit more robust although with plenty of winds. Read on for details.

In the short run and the current run of small S swell bottoms out tomorrow with minor leftovers to a foot or so at most places and a few 2ft sets at S facing beaches. There may be some traces of long period S swell glancing the coast in the a’noon but it’s hard to see more than the occasional 2ft+ set at S swell magnets. Light morning NW winds should swing N’ly then NW-W/NW later in the a’noon as a front approaches. With the favourable winds it’s worth a squizz at S swell magnets to see if they are hoovering up any of the S swell traces on offer.

Winds tend W/SW overnight as the front and a small trough of low pressure push into the Tasman early Wed (see below). Those winds should tend SW through the morning then S-S/SE in the a’noon as the front/trough move NE. Small leftovers in the morning should see some rideable options at S facing beaches, albeit a little wind affected. A modest bump in S swell to 2-3ft in the a’noon will be wind affected at S facing beaches and tiny elsewhere.

That small bump in S swell is still in the water for Thurs but with lingering S’ly winds quality looks poor. We may see a few rideable options north of the Harbour with a morning SW breeze but everywhere else looks like it will be wind affected. Winds should tend NE through the day as high pressure moves into the Tasman. 

Light/variable winds to end the working week under a weak, troughy environment. Not much swell energy expected. A small blend of leftover S-SE and traces of longer period S may see some 1-2ft surf at S facing beaches, with most places around a foot or so. 

This weekend (Aug 26-27)

Looks like we will see some robust S’ly winds develop this weekend as a coastal trough and strong high approaching Tasmania combine. Sat morning should still see light winds but as the day goes on, those winds look to freshen. Small surf early in the 1-2ft range tends to increasing S’ly windswell through the a’noon, likely up into the 2-3ft range but we’ll finesse size and timing through the week. 

Sunday looks even windier at this stage, although there’s still substantial model divergence about a potential low pressure trough off the NSW Coast with EC suggesting a trough off the Mid North Coast and direct SE flow aimed at Central NSW, which would see mod/fresh SE winds and a substantial SE short range swell across the region. GFS has a more diffuse area of low pressure moving NE into the Tasman with a broad S-SE wind field through the Tasman. We’ll still see S/SE-SE winds under this scenario with modest building SE swells. We’ll pencil in surf building into the 3-4ft range for now, wind affected at most places and finesse through the week.

Next week (Aug 28 onwards)

Winds from the S-SE and plenty of short range SE swell under current modelling to start next week. Expect revisions with the model divergence on offer but size in the 4ft+ range looks likely with mod/fresh S/SE-SE winds.

We should see winds ease through the week and swells ease back slowly, hopefully with a sweet spot of cleaner conditions which looks likely Wed at this stage. 

Further ahead and there is quite a bit on the radar. We may see a fetch out of Cook Strait mid next week, with possibly a lingering E’ly fetch through the Northern Tasman into South Pacific corridor. That suggests at least modest amounts of E’ly quadrant swell around later next week. 

We’ll focus on the specifics as we move through the week and model runs start to sharpen focus.

Check back in on Wed for the latest.