South Australian Forecast by Craig Brokensha (issued Monday 27th June)

Best Days: South Coast Tuesday and Wednesday, Mid Tuesday morning, both coasts Friday, South Coast all weekend

Recap

Excellent waves across the South Coast both Saturday and Sunday with easing clean 3-5ft surf on the former, back to a smaller 2-3ft Sunday, bigger and better at Waits with Sunday being the standout west of town. The Mid was a clean and good 2ft Saturday with 1-1.5ft waves Sunday.

Today a large new W/SW groundswell has come in a bit under expectations, which is a bit surprising seeing the numbers that came in across Western Australia over the weekend. Cape du Couedic rose mid-morning though to the peak is due into the afternoon. We should still see 2-3ft sets on the Mid (now showing signs on the South Port cam) and 4-5ft waves off Middleton, a touch under Friday's expectations.

This week (Jun 28 – Jul 1)

This afternoon's strong W/SW groundswell will peak overnight and ease off through tomorrow. Middleton should ease from 3-4ft+ with 6ft sets at Waits and Parsons, while the Mid is expected to drop from 2ft.

Our new SW groundswell due late in the day tomorrow will only likely arrive after dark, with Wednesday morning offering the best size. This swell is being generated by a tight and intense mid-latitude low passing under us, with satellite observations confirming a fetch of storm-force W'ly winds under WA.

This low is currently weakening, with the swell due to come in Wednesday morning to 3-4ft at Middleton and 5-6ft at Waits and Parsons, easing through the afternoon and becoming small Thursday (2ft Middleton). The Mid isn't due to see any major size with 1-2ft sets possible on the favourable parts of the tide Wednesday.

Conditions are looking great all day down South tomorrow with a persistent moderate to fresh NW'ly, (lighter and more manageable on the Mid), with strengthening N'ly tending N/NW winds Wednesday. This will likely also kick up a tiny NW windswell on the Mid.

Into Thursday a vigorous cold front is expected to push into the state, with it currently in the form of a polar low in the Heard Island region. This polar low will generate an inconsistent SW groundswell for Friday, but the front pushing ahead of it is due to kick up a building short-range SW swell through Thursday afternoon, peaking Friday.

The Mid should kick to a stormy 3ft through the day with gusty W/NW tending strong SW winds. Middleton is expected to build to 3ft+ later in the day with bigger sets at Waits and Parsons.

Friday should then see solid 3-5ft sets off Middleton with more size at Waits and Parsons, with the Mid easing back from the 2ft+ range. Our models are combining the long-range and short-range energy incorrectly and over-forecasting the size. Winds are expected to be from the W/NW most of Friday, light across the Mid creating workable conditions.

Into the weekend a good reinforcing SW groundswell is due Saturday from a broad fetch of pre-frontal W/NW gales moving under us. Middleton will likely be the best bet holding between 3-4ft with 5-6ft sets at Waits and Parsons, and NW to W/NW winds will favour protected locations all weekend. The Mid will see small bumpy surf likely between 1-2ft on the favourable parts of the tide.

Longer term a strong cold-outbreak pushing up and into Vicco is due to produce moderate to large levels of S/SW swell for early next week, but more on this Wednesday.