Western Australia Surf Forecast by Craig Brokensha (issued Wednesday 17th June)

Best Days: Friday for experienced sufers, Saturday and Sunday selected spots, early Monday selected spots

Recap

Early light winds across the South West and a window of OK large waves to 8-10ft, while Perth and Mandurah were great with clean conditions and surf to 2-3ft across the former and 3ft+ in the later.

Today the surf was poor or deteriorating with strengthening N/NW winds which are now gale-force across the South West along with a drop in swell. Perth was best early but now poor.

This week and weekend (Jun 18 – 21)

The strengthening and gale-force N/NW breeze is due to a strong mid-latitude approaching from the west-southwest, with it expected to cross the coast later this afternoon and this evening, bringing strong to gale-force W'ly winds.

An XXL W/SW groundswell will follow it into tomorrow, mixed in with local windswell and there's no change to the expected size with the South West due to build to a stormy 15ft+, 5-6ft in Mandurah and 3-5ft across Perth. Conditions will remain poor though with strong onshore W/SW winds, easing slightly and tending more SW through the afternoon.

The surf will start to ease Friday but from a still XXL 12ft to possibly 15ft in the South West, 4-5ft across Mandurah and 3-4ft in Perth and our swing to offshore winds is still on track.

A high will move in tomorrow evening and winds should swing around to the E/NE across all locations through the morning Friday, more NE into the late morning and early afternoon before tending variable. Perth and Mandurah will be cleanest with some leftover lump and wobble due across the South West, though improving as the day progresses.

The weekend will still see freshening E/NE tending NE winds as the swell continues to ease, favouring some breaks over others. Size wise the swell will be much smaller and down to 4-5ft+ across the South West, easing further through the day, 2ft in Mandurah and 1-2ft across Perth.

A new W/SW groundswell is due to build through Sunday with a secondary reinforcing increase for Monday and Tuesday.

This is being generated by a strong mid-latitude front that's currently south-east of Madagascar, projecting a fetch of gale to severe-gale W/SW winds towards us. The front will broaden and weaken tomorrow afternoon and evening but a secondary burst of W/SW gales towards us, on top an active sea state should produce a secondary pulse of similar sized and reinforcing swell for Monday.

The first long-period swell should arrive Sunday and build towards a peak later afternoon to 8ft to occasionally 10ft across the South West, 3ft+ in Mandurah and 2-3ft across Perth, holding Monday with the secondary pulse. A slight drop in size is then likely Tuesday.

Unfortunately as the frontal progression as a whole approaches us through the weekend, winds will deteriorate, swinging from the E/NE-NE early Sunday to the N/NE into the afternoon, stronger N/NE on Monday and then W/NW Tuesday.

This will be associated with a strengthening frontal progression south-west of us, bringing more large onshore surf late week, but more on this Friday.