Western Australia Surf Forecast by Ben Matson (issued Friday 28th October)

Best Days: Sat: bays and points down south. Sun: fun clean metro beaches early, small bays and points down south. Mon/Tues: easing swells and clean morning conditions down south. Wed: unusual small/mod S'ly swell for Margs, with offshores. Fri thru' Mon: building series of long range W/SW swells. 

Recap: Wednesday’s large swell across the Margs coast eased into Thursday but we’ve seen another solid swell build throughout today, and early light offshore winds are now moderate onshore. Perth and Mandurah beaches have had fun small waves for the last few days with light offshore winds and afternoon sea breezes. 

This weekend (Oct 29th - 30th)

Saturday looks like a write-off across most coasts.

A vigorous cold front will cross the coast in the morning, swinging fresh and gusty W’ly winds around to the SW for much of the day. The current swell increase will continue to build through Saturday and we should see some very large waves across the exposed Margaret River coastline by the afternoon, somewhere up in the 10ft+ range, but with winds around to the SW and this level of size there’ll be good options across the protected bays and points. 

Perth and Mandurah coasts won’t fare very well on Saturday thanks to the persistent onshore airstream however there will be small waves in behind sheltered groynes and the like. Set waves should push the 2-3ft+ mark across Perth metro beaches by the afternoon, and a little bigger in Mandurah.

Sunday will see a reasonable improvement across the Margaret River coastline, with steadily abating SW winds overnight Saturday possibly swinging light to moderate S’ly by Sunday morning. There’ll still be some leftover lumpiness through the lineup and exposed locations are looking at early 6-8ft sets ahead of an easing trend during the day. Once again, protected bays and coves will be your best option though it will be abating in size. 

The Perth and Mandurah coasts look much better for Sunday morning with winds expected to swing light SE before dawn, allowing conditions to clean up quite a bit. Surf size should manage 2-3ft sets across Perth metro beaches, slightly bigger in Mandurah but with a slight easing trend through the afternoon, which will be accompanied by fresh afternoon sea breezes. So, aim for the early session here.

Next week (Oct 31st onwards)

The weekend’s swell is expected to steadily abate through Monday and further into Tuesday. Weak synoptic patterns will create typical light offshore winds and afternoon seabreezes for this time of the year.

A small polar low developing off the ice shelf SW of Heard Island today will intensify as it tracks NE up towards the mainland over the weekend, though it’ll be right on the eastern periphery of the swell window so the resulting energy will just glance the WA coast with an almost straight southerly direction.

The leading edge of this swell may nose into the Margaret River coastline on dark Tuesday (surf heights will otherwise bottom out on Tues in the 3ft range with light offshore winds and sea breezes), but it’ll show best on Wednesday. This swell direction is a little unusual and won’t show up at many breaks, probably bypassing all but the most exposed south facing locations who could pick up stray 3-5ft sets - there will be very long breaks between waves. Otherwise, expect much smaller surf at most locations. Conditions should be clean with light winds and sea breezes. 

Perth and Mandurah won’t enjoy this swell direction at all so Tuesday and Wednesday are looking at residual energy around the 1ft mark both days with light offshore winds and fresh afternoon sea breezes. 

Looking further ahead, and a developing conveyer belt of storms in our western swell window - quite north in latitude, just NW of Heard Island over the weekend - are expected to generate our next run of groundswell.

Overall, the significant travel distance between these storms and the mainland will keep a lid on likely wave heights and swell consistency, but we should see a series of small long period W/SW groundswell arriving from Friday onwards, providing good waves across the state as they build towards a peak on Sunday or maybe even Monday. 

I doubt we’ll see much more than very inconsistent sets between 4ft and maybe 6ft at exposed beaches across the Margaret River coast at the height of the swell (Sun or Mon) but the extra west in the swell direction may provide a slightly different response at some of the reefs that are more tuned for regional south-west swell energies. These swell sources often produce good (small) surf across the Perth and Mandurah coasts, owing to the slightly wider swell window and reduced shadowing by geographical features. 

Anyway, it’s certainly an event to keep a close eye on over the coming days though.