West Australian Surf Forecast by Guy Dixon (issued Wednesday 23rd September)

Best Days: Early Saturday and virtually all day Sunday

Recap:

Thursday hit a bit of a flat spot in terms of surf. The South West was offering 2-3ft peaks at exposed beaches in the morning under light east/northeasterly winds. A cooler change soon moved through and created a few bumps putting it on hold for the day. Metro beaches were virtually unsurfable unless you were under 30 kilos or on a SUP, but remained clean in the morning. That same southwesterly change created a few bumps in the afternoon however.

Light/moderate southwesterly breezes dominated the WA coastline today and whipped up a few bumps on top of an inconsistent 3ft swell with the odd 4ft set occasionally. It was surfable, but the quality was generally low and there wasn’t a whole lot of reason to get motivated. Perth and Mandurah were a weak 1ft all day, clean in the morning under light southeasterly winds, soon tending onshore and deteriorating.

This weekend (Saturday 26th - Sunday 27th):

We are still on track for a small lift in energy for Saturday. Throughout the day, the surf will build to the 4-5ft range generated by a southwesterly trailing fetch moving across Heard Island which we saw in Wednesday’s notes. A second small pulse will approach the South West in the late afternoon, peaking overnight. Sunday will hold at a similar size in the morning, gradually easing throughout the afternoon. Perth and Mandurah area only likely to see a small lift to around 1-2ft on both days, easing throughout Sunday.

The South West will be under a light southerly breeze on Saturday morning, potentially southwesterly closer to Cape Leeuwin. Breezes will gradually swing around to the south/southeast and increase late in the day. Perth and Mandurah will start out under light southeasterly breezes, increasing and tending south/southwesterly late. Sunday’s winds will be much more favourable, holding moderate easterly all day across the coast, lightening and tending southerly late.

Next week (Monday 28th – Friday 2nd):

By Tuesday, the swell will have faded to a low of around 2-3ft for the South West and back in to grom territory for Perth and Mandurah while we all eagerly await the next significant system. It won’t matter too much as onshore breezes dominate.

A small amount of energy will allow for a late increase on Wednesday to the 3-4ft range for the South West, and 1ft for Perth and Mandurah under light northwesterly winds (moderate for the southwest). The real energy is due late in the week however.

A node of the long wave trough will become more active over the Indian Ocean mid-way through the week leading to more pronounced frontal activity. A long range system originating from under  South Africa on the weekend will generate a particularly large (and growing) fetch with 40-50kt core winds. This system will move over the Heard Island region around Monday/Tuesday becoming broader but with less intense winds.

The effects of this system will first be felt on Thursday where the surf should build to an inconsistent 4-6ft across the South West with the long period forerunners.

Friday should continue to build to around 6-8ft+ on dark, potentially nudging the 10ft range by Saturday. Perth and Mandurah should build to around 2-3ft on Friday, holding in the 3ft range throughout Saturday.

Unfortunately gusty northwesterly winds have the potential plague the coast throughout Thursday and Friday, with the only window of opportunity in the morning of Thursday when winds are at their lightest and most northerly. Perth and Mandurah have the outside chance of seeing northeasterly breezes early if the models come into alignment the way we want them to.

We hope that a ridge will have become established by Saturday, but it’s just too far out to say with any confidence. My prediction is that it will be wind affected, but I’m hoping to be proven wrong. It’s early days, I want to remain conservative this far out, but we can be confident that we will see building surf this time next week after a pretty quiet few days.