Fun mixed bag this week as summer pattern slowly fades

Steve Shearer picture
Steve Shearer (freeride76)

Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Mar 18th)

Features of the Forecast (tl;dr)

  • Easing S/SE groundswell Mon with light/mod NE winds
  • Mix of swells Tues with freshening NE winds
  • Potential fun window of E/NE and NE swells Wed with a brief W'ly period before gusty S'lies kick in
  • Spike in S-S/SE swell Thurs with S-SE winds easing
  • Small, fun weekend with light winds
  • A few swell sources on the radar for next week- check back Wed for updates


Quite a bit of swell over the weekend with Sat seeing around 3-4ft of SE-S/SE swell with conditions mostly hampered by onshore SE-E/SE winds although winds did back down through the day . Sunday was similar size to start with with light NW-N/NW winds reasonably widespread and a S/SE groundswell filling in during the a’noon. A range of sizes reported from 3-4ft topping out at 4-5ft with the occ. 6ft set on the lower MNC. Still some S/SE swell around today with mostly 3-4ft surf ( a few 4-5ft outliers reported) and clean conditions under light winds for the morning session before mod NE winds clocked in.

Still some girth in the sets this morning

This week (Mar 18-22)

Pretty typical late Summer pattern with a high in the Tasman and a maturing trade-wind flow in the Coral Sea, linked to an active monsoon trough with a small embedded low in the Coral Sea. There is a tropical cyclone in the Gulf of Carpentaria which formed over the weekend but this system is expected to track inland over the NT and Kimberley regions and not be a swell source for the East Coast. We’ll see this pattern disrupted mid-week by an aggressive trough which brings S winds and swell before the next high slowly resets the trade pattern, this time further north in the Coral Sea.

In the short run we’ll see the NE flow strengthen along the temperate NSW coast, reaching in excess of 20 knots through the a’noon. Most of the S/SE energy will have dissipated leaving a mix of NE and E/NE swell from the top of the high, offering workable options in the 3ft range.

Similar size or a tad more into Wed, with a little more NE dominated windswell in the mix,  with N’ly winds early up to around lunch-time where the S’ly change comes blasting in. Expect winds in excess of 20kts through the a’noon, tending S/SE by close of play. A small window of offshore winds may present itself before the change but it looks to be relatively brief (an hr or two) so you’ll need to be on it. Otherwise right around the change or after for protected N facing spots but even those are likely to be wind affected through the a’noon. Short range S swell is expected to rise through the a’noon but very raw and ragged. 

By Thurs the trough will have moved away but we’ll still see a mod S’ly flow, tending SE in the a’noon and dropping back in strength. Plenty of size in the morning in the 5-6ft range but that will mostly be local, short period stuff, so expect that to ease off quite quickly in the a’noon as the fetch moves away. Also in the mix will be continuing fun sized E/NE swell to 2 occ. 3ft.

Easing winds for Fri with a good chance for morning land breezes before light/variable seabreezes kick in. Not much swell on offer but a small blend of E/NE and S/SE should offer up some 2-3ft surf in the morning, dropping back during the day.

This weekend (Mar 23-24)

Generally easing swells with light winds this weekend. Weak, troughy winds look likely for both days so morning offshores and light/variable breezes through the day should offer mostly glassy surf. 

Swell tap is mostly turned off though so you’ll need to be ready to grovel. 

The tradewind band contracts eastwards later this week so that swell source will slowly dry up, leaving an inconsistent 1-2ft signal Sat, smaller Sun.

Frontal activity below the continent is not well aligned but it does get pretty busy down there later this week, so small amounts of refracted S swell should offer up some 2ft sets at S swell magnets over the weekend - we’ll hope for a slight upgrade through the week.

All told, there should be just enough for a fun wave at open beaches and swell magnets. 

Next week (Mar 25 onwards)

Small start to next week with reinforcing high pressure gradually shifting into the Tasman early next week. We should see a day of light winds Mon with small S and E swells to 2ft, possibly a notch bigger at S swell magnets depending on how the frontal activity shapes up.

That small swell signal persists into the middle of next week.

From there we may see NE winds freshen and bring some NE windswell, as well as small E/NE swell from the top of the high. 

The area around the eastern ice shelf still looks active with a possible fetch there early next week, so we’ll keep an eye on that.
In short, nothing major on the radar but a few sneaky swell sources that should offer up some rideable options.

Check back Wed for the latest. 


Craig's picture
Craig's picture
Craig Monday, 18 Mar 2024 at 1:29pm

Here's a great buoy trace of the combined S/SE groundswell and lower period NE windswell (appearing as E-E/NE).

You can see yesterday it was mainly S/SE groundswell but from early this morning the NE windswell started to dominate, with both swells of equal weighting, resulting in the back and forth..

Anthony Gale's picture
Anthony Gale's picture
Anthony Gale Monday, 18 Mar 2024 at 6:30pm

not the mhl buoy is it?

Craig's picture
Craig's picture
Craig Tuesday, 19 Mar 2024 at 6:11am

Nah, Port Botany.

Anthony Gale's picture
Anthony Gale's picture
Anthony Gale Tuesday, 19 Mar 2024 at 9:26pm

Do you have a link for that one please mate

FrazP's picture
FrazP's picture
FrazP Tuesday, 19 Mar 2024 at 8:57am

Not sure if I was dreaming but it seemed to pulse strongly late evening when I was out. Checking the buoy off Kurnell it suggests a spike to 4m @ up to 15 secs.

Craig's picture
Craig's picture
Craig Tuesday, 19 Mar 2024 at 9:08am

Last breath of the S/SE groundswell probably?

FrazP's picture
FrazP's picture
FrazP Tuesday, 19 Mar 2024 at 12:51pm

Maybe a case of don't question just accept !

It was a fair bit bigger than it had been.

john_c's picture
john_c's picture
john_c Tuesday, 19 Mar 2024 at 9:53am

Super fun this morning at my local on the NB.

sean killen's picture
sean killen's picture
sean killen Wednesday, 20 Mar 2024 at 8:43am

Very slow this morning one end pumping 4ft the north facing end 2ft at best..still fun though

belly's picture
belly's picture
belly Wednesday, 20 Mar 2024 at 11:31am

Bit dire for obs down south, Montague Island wind has been down for 2 weeks or so, Eden buoy went adrift over a week ago, and now no data feed for Batemans Bay buoy.

Craig's picture
Craig's picture
Craig Wednesday, 20 Mar 2024 at 11:34am

Ughh and no Maria either!