Western Australian Forecast by Steve Shearer (issued Wed November 13th)

Features of the Forecast (tl;dr)

• Small but fun waves Thurs/Fri with offshore winds Thurs, tending more S’ly on Fri
• Nice sized S/SW swell this weekend with offshore winds both days
• Long range swells next week with offshore winds
• Moderate reinforcing swells later next week with a bias towards offshore winds

Recap

Small surf yesterday with onshore winds, initially around 2ft in the SW did build in the a’noon and today we’ve seen a nice reinforcing pulse of swell in the 4-5ft range between the Capes, smaller 2ft or less in Mandurah/Perth. Winds were offshore E/SE before a S’ly seabreeze kicked in at mod paces.

Nice conditions this morning

This week and next week (Nov11 - Nov 22)

We’ll see SE winds again tomorrow (slightly more S than todays winds and with an earlier seabreeze) as a large high pressure belt extends from under the state out into the Indian Ocean. Size drops back into the 3ft range tomorrow, similar for Fri.

We’ll see winds shift S’ly on Fri as a front just tips the state and a new high ridges in.

That front is tied to a fetch of SW winds which tracks towards WA. Windspeeds are a little lower than models initially expected so size gets a downgrade. We should see undersized 3ft surf Sat morning, building into the 4-5ft range during the day. Early winds from the SE-S/SE tend S-S/SE in the a’noon at mod/fresh paces.

Those winds should tend more SE-E/SE on Sun as high pressure slips under the state and a coastal trough moves southwards from the Gascoyne region. Sundays size should hold in the 4-5ft range, 2ft in Perth/Mandurah so there should be some good waves at exposed reefs and beachies.

Winds will freshen from the NE on Mon, and tend more N’ly on Tues as the coastal trough of low pressure drifts towards the SW corner. Surf-wise a storm force system under Africa sends long period forerunners arriving Mon in the 19-20 second band before the bulk of the swell energy in the 16-17 second band fills in later Mon and Tues with size to 4-5ft extending into Wed. Expect a slow, pulsey swell due to the travel distance. Winds look good with high pressure under the state generating E to E/SE winds both days tending more E-E/NE on Wed. There'll be some closer range energy in the mix from a disturbance passing NE of Heard Island over the weekend.

Further ahead and a similar moderate disturbance passing under Heard Is provides reinforcing energy through Thurs and Fri in the 3-4ft range.

Longer term and we may see a slow moving low develop around Heard Island later next week, suggesting sizey SW swell early in the following week. GFS is much more bullish about this scenario than EC so we’ll flag it for now and see how it looks Fri. 

Seeya then.