Western Australia Surf Forecast by Craig Brokensha (issued Wednesday 19th August)

Best Days: Early tomorrow keen surfers in the South West, all day to the north, Margs and Mandurah Friday, dawn Saturday keen surfers Margs, Monday and Tuesday next week

Recap

Large and onshore waves continued across the South West yesterday, similar in Perth and Mandurah, but light offshore winds have provided fun, clean 2ft sets across those latter locations today, with bumpy 6ft surf around Margs this morning.

This week and weekend (Aug 20 - 23)

We've got a little aberration in the local winds for the South West tomorrow morning. A small trough now looks to spoil the offshore that was forecast, but the hi-res models have more variable winds through the morning before shifting onshore.

With onshore W'ly winds just to the west though, the surf will likely come in lumpy and not ideal (keep your expectations lowered). To the north conditions look better with an E/NE offshore and afternoon sea breezes.

Our new W/SW groundswell is still on track, with inconsistent 4-6ft sets due to push in across the South West, 2ft across Perth and Mandurah on the sets.

This swell will then ease on Friday with a true E/NE offshore across the South West (E/SE-E further north), variable into the afternoon.

Moving into the weekend our new inconsistent W/SW groundswell building Saturday and peaking Sunday is looking on track as well, though so are the onshore winds Sunday.

The swell has and is still being generated by a mid-latitude frontal progression that formed south-east of South Africa and pushed east towards us.

A mixed though consistent fetch of strong to gale-force W/SW winds has moved through our swell window and is now dipping south-east across the Heard Island region.

An initial pulse Saturday looks to come in around an inconsistent 4-5ft in the South West, tiny to the north and with early N/NE tending N/NW winds ahead of a trough.

The trough will move through Sunday bringing onshore W tending W/SW winds, spoiling the bigger pulse of groundswell that's due to come in around 6ft+ in the South West, 2ft+ across Mandurah and 2ft in Perth.

We'll hopefully see winds go light offshore on Monday but with the swell on the ease, clean again Tuesday but smaller again.

Longer term we're looking at a larger W/SW groundswell for late next week and weekend across the state, though the local winds are up and in the air. More on this Friday.