South Australian Forecast by Craig Brokensha (issued Monday 17th April)

Best Days: South Coast every day, Mid Coast tomorrow afternoon through the weekend

Recap

Great waves across both coasts Saturday with a good W/SW groundswell to 2ft to occasionally 3ft on the Mid Coast, while Middleton saw solid clean conditions before sea breezes kicked in.

Sunday unfortunately failed to see the onshore breeze overnight backing off, resulting in average onshore conditions, while the Mid Coast dropped back to a smaller but clean 1-2ft.

Today a new SW groundswell seen yesterday afternoon was holding strong down South (although inconsistent) with a return to offshore winds, while the Mid Coast is continuing around an inconsistent 1-2ft.

This week (Apr 18 – 21)

We've got an excellent week of surf ahead for the South Coast, and also at times for the Mid Coast.

Today a mix of long-period SW groundswell and reinforcing W/SW swell are breaking across the region, with a temporary low point in energy due early tomorrow morning.

This will see 3ft sets across Middleton with 1ft+ waves on the Mid, building again from late morning with the arrival of a strong new W/SW groundswell.

The source of this swell was a great pre-frontal fetch of severe-gale W/NW winds ahead of the stronger storm-force fetch linked to Wednesday's swell.

Tomorrow afternoon's increase should see the Mid Coast kicking back to a good 2ft if not a little bigger at magnets, and 3-5ft off Middleton. Conditions are looking great all day with E/NE tending variable winds on the Mid Coast and N/NE tending NE and then E/NE breezes down South.

Wednesday's large long-period SW groundswell is on track, with satellite observations confirming an amazing fetch of 50-55kt winds over an already active sea state.

The swell is due to arrive early Wednesday morning, filling in strongly for the morning and coming in at an easy 6ft on the sets off Middleton and a great 2-3ft on the Mid Coast.

Winds will be excellent all day for the South Coast with a fresh but easing N/NE tending N/NW breeze, while the Mid should be OK early before becoming bumpy as winds tend more north.

Later in the day Wednesday the swell should start to ease, with Thursday still being solid but smaller with early light offshore winds. Both coasts look to offer good conditions, smaller again Friday morning.

Come Friday afternoon another good W/SW groundswell is due to fill in across the state, produced over the coming days by a strong mid-latitude front firing up towards WA over the coming days.

This swell will favour the Mid with a pulse to 2ft+ due through the afternoon, while the South Coast looks to kick back to 3ft to occasionally 4ft at Middleton (larger at Waits and Parsons). More variable breezes from the SE should keep both coasts clean, with sea breezes into the afternoon with the new building swell.

This weekend onwards (Apr 22 onwards)

Friday afternoon's swell should ease back through Saturday with excellent N/NE offshore winds, variable into the afternoon.

Into Sunday a similar sized W/SW groundswell is due again (if not a touch bigger) produced by back to back mid-latitude fronts pushing up towards WA again. With the dual action we could see a touch more size for the Mid, kicking to 2ft to occasionally 3ft Sunday with 3-4ft sets down off Middleton down South.

Both coasts are looking to see clean conditions continue with morning variable winds ahead of sea breezes, but more on this Wednesday.