Western Australian Surf Forecast by Steve Shearer (issued Friday September 8th)

Features of the Forecast (tl;dr)

• W/NW-NW winds Sat (possibly NE early in Mandurah/Perth)
• Moderate sized + W/SW groundswell building late Sat, easing Sun
• Moderate W/NW tending fresher NW winds Sun (E/NE early to the north)
• Similar winds Mon with an easing swell
• Large mix of W/SW groundswells building Wed with strong NW winds
• XL surf next Thu and Fri with strong NW-W/NW winds, tending W/SW Fri

Recap

Nice sized 6ft+ swell for the Margarets region yesterday, smaller 2-3ft in Perth and 3ft in Mandurah with clean conditions under E’ly winds. Size has dropped today, topping out around 3-4ft between the Capes with offshore E’ly winds. 

This weekend and next week (Sep 9 - 15)

No change to the weekend f/cast. Sat starts small in between swells with a late kick in W/SW swell as a cut-off low approaches form the W, dissipating as it approaches the SWWA coast. Early winds should tend N-N/NW (more NE in Perth-Mandurah) before swinging mod W/NW-NW through the day.  We should see a moderate + sized pulse of W/SW groundswell that should kick to 6ft+ on dark Saturday in the South West, peaking overnight and easing steadily from a similar 6ft+ Sunday morning. Perth and Mandurah should see the swell peak Sunday morning with 3ft sets across the latter and 2-3ft across the former.

Winds will remain onshore for the South West but only moderate, strengthening from the NW through the day. Perth and Mandurah should see more variable E/NE winds through the morning.

Similar winds are due Monday but with easing surf.

Into next week and very active Indian Ocean storm track spawns a slow moving massive gyre with multiple (at least 3) back to back to back severe gale fetches which will generate L to XL surf, primarily benefitting the NW and Indonesia. SW WA will be mostly in the storm track and thus subject to a mostly stormy, onshore flow, with the breaks between onshore episodes unlikely to be sufficient for surf to clean up away from a few select winter spots.

W’ly swells look to build Tues into the 6ft range in the SW- 3ft in Perth and Mandurah under a lighter onshore flow.

There may be a brief window of NE winds Wed morning in Perth/Mandurah before winds shift strong W/NW as a major low approaches. Surf will build from large (6-8ft) to XL (12-15ft) during the day, possibly firing up some novelty winter waves.

Thurs looks gigantic and stormy, possibly in excess of 20ft but under such a fresh onshore flow (W/SW) as the system passes across the SW corner. 

Elevated wave heights are expected right through next week, coming down from Thursday peak,  slowly through Fri and into the weekend, but unlikely to drop below 8ft.

Unfortunately SWWA will still be in the storm track during this period so onshore winds will persist. 

More frontal activity at SWWA latitudes looks likely into early next week so it might be a while before conditions clean up enough to surf the reefs. Late season Indo or NWWA would be the go, with plenty of chunky, albeit onshore beacbhbreaks for Perth/Mandurah on the menu. 

Check back Mon for the latest and have a great weekend!