Extended run of favourable conditions
Western Australian Surf Forecast by Ben Matson (issued Thursday 13th May)
Features of the Forecast (tl;dr)
- Easing size Fri/Sat, clean with E'ly winds
- Inconsistent mix of new groundswells Sun, continuing offshore winds
- Fun waves at exposed coasts for much of next week thanks to light winds
- Decent pulse of swell later Wed/Thurs, then Sat
Developing southerly winds wiped out surf prospects on Wednesday, however today has seen an about-face with a large groundswell pushing 10ft in the Margs region, brushed clean with moderate to fresh E/SE winds. Wave heights have reached 3-4ft in Mandurah and 2-3ft across Perth’s metro beaches, with similar clean conditions (but limited surf options thanks to a distinct lack of banks).
This week and weekend (May 13 - 16)
Today’s large swell will slowly ease through Thursday though early morning should still be large, somewhere between 6ft and maybe 6-8ft at exposed Margs breaks, abating to 4-6ft through the day. We’ll see smaller surf racing across metro coasts, around 2ft in Perth and 3ft in Mandurah through the morning (smaller later).
A high pressure system to the south of the state and a deepening trough well east of WA will maintain moderate to fresh E’ly winds across the region. So, conditions are looking to remain excellent.
The weekend will maintain clean conditions for all of Saturday, and early Sunday though the weakening remnants of the Indian Ocean trough - which will move slowly west over the coming days - will swing the wind to the north at some point on Sunday. No major strength is expected however it does need to be factored in.
As for surf, Saturday will see a continual easing trend from Friday (say, 4-5ft Margs, 1ft Perth, 2ft Mandurah) but Sunday as a series of new long period groundswell that’ll boost wave heights through the day.
As mentioned on Tuesday, these swells have originated from two sources - a deep polar low below South Africa earlier this week, and a second low deepening near Heard Island today. The latter was expected to be responsible for the most size, but the latest model runs have pulled back its strength so I’m marginally pulling back my expectations for Sunday, with wave heights expected to reach an inconsistent 5-6ft across the Margs region.
There won’t be much on offer across the metro beaches, maybe some stray 2ft+ sets across the Mandurah region and a slow 1-2ft in Perth.
Next week (May 17 onwards)
The latest model guidance has throttled back the storm track for next week, suggesting a slow week of moderate groundswells across the region but fortunately very little in the way of local synoptic wind. This means we’ll see clean conditions most days.
For the most part, wave heights should hover in the 4ft range at exposed beaches, though Wednesday is likely to build towards 5-6ft into the afternoon (easing Thursday), from a reasonable frontal sequence pushing east of Heard Island over the weekend - but it’s not looking as good as it was a few days ago. Surf size will remain small across metro coasts for a while.
The next groundswell event is pegged for the following Saturday but I’ll have more on that in the next forecast update (Saturday).