South Australian Surf Forecast by Ben Matson (issued Monday 29th May)

Best Days: Tues: late lumpy options on the Mid. Wed: improving surf on both coasts with easing surf. Thurs/Fri/Sat: small clean surf down south. Late Thurs/Fri: small new pulse for the Mid, clean with offshores. Sat: small distant groundswell for the Mid. Sun: bigger groundswell for both coasts but tricky winds for the Mid.

Recap: Saturday delivered plenty of waves at Victor under offshore breezes, with small residual lines on the Mid Coast. A new swell build strongly on Sunday though winds freshened from the west with a cold front. Sunday’s new swell is now easing across all coasts though we’re still seeing plenty of great waves at Victor under a NW airstream. The Mid Coast is bumpy with onshore winds. 

Note: our computer model surf forecast graphs will be a little funky for the next day or two.. read more here: https://www.swellnet.com/forums/website-troubleshooting/352217

This week (May 30 – Jun 2)

A cold front passing south of the state overnight will swing winds around to the SW, then S, creating poor conditions in most regions for Tuesday. 

The leading edge of a new long period groundswell is expected to make landfall in the morning, but it’s not expected to begin building properly across the coast until the middle of the day, so in general we can expect this swell to go to waste down at Victor thanks to the onshore airstream.

However, winds will ease rapidly across the Mid during the day and we could be under a moderate S'ly tending S/SE breeze late afternoon, which should assist in helping the small new groundswell produce some OK waves. I haven’t had time to hindcast the specifics of the early incarnations of this system but a brief look at the weekend's satellite data didn’t show any major strength in the fetch (i.e. nothing greater than 40-50kts), and the bulk storm track was quite far south. As such I’m going for a late afternoon tidal kick to 2ft+ across the Mid Coast whilst the Victor stretch could see 3-5ft sets right on dark.

Light variable winds are then expected on Wednesday before an extended run of NE winds from Thursday through Saturday. 

Wednesday should see a rapid improvement in surf quality at Victor (though likely with still an early wobble), and easing 3-4ft sets at Middleton down to 2-3ft during the day and into Thursday morning. The Mid Coast should see small waves through Wednesday around 1-2ft, easing to 1-1.5ft Thursday morning.

On Thursday afternoon, a new W/SW swell is expected to push through, providing energy for the afternoon and perhaps Friday morning. This swell will have been generated by a cut-off low currently forming west of Margaret River, which is then expected to take an unfavourable SE track perpendicular to our swell window over the coming days. This will limit swell potential for us, in fact we’ll probably see the most size from the pre-frontal NW fetch (poorly aimed, but strong and wide enough to allow for some spread back into the mainland).

This swell should produce small clean waves across the Mid Coast under an offshore NE breeze, around 1-2ft at times. The westerly component in the swell will limit size at Victor to 1-2ft across the Middleton stretch with bigger waves at Goolwa and Waits, but it’ll be super clean.

This weekend (Jun 3 - Jun 4)

The weekend looks really interesting.

A series of new long period groundswells are expected to arrive, generated by a very intense series of fronts currently developing near Heard Island.

The enormous travel distance and the northern position of the storm track (relative to our swell window) means we’ll see long breaks between set waves, and quite a lot of west in the swell direction too - great for the Mid Coast but not so great for the South Coast.

Saturday’s swell looks to be the smaller of the two, and should supply infrequent 1-2ft waves across the Mid Coast whilst Sunday’s even longer period swell (peak swell periods of 19-20 seconds) could produce occasional 2-3ft sets. Expect very long breaks between set waves. 

Down south, we should see a little more more size though the westerly component in the swell direction will restrict size here, maybe 2-3ft Saturday at Middleton building to 3-4ft Sunday, with bigger options west and east of here. 

The only concern are the winds. Saturday should retain a light pressure gradient under a broad, slow moving high in the Bight but a approaching front may swing the winds around to the NW with a freshening trend on Sunday. This is fine for Victor but could create some problems across the Mid Coast.

Let’s have a closer look on Wednesday. 

Next week (Jun 5 onwards)

A very active frontal passage through our far and mid-range swell windows will keep the South Oz coast very busy through much of next week. It’s too early for specifics but things are lining up for an extended period of great waves - especially along the Mid Coast too. More on this in Wednesday’s update.