South Arm Surf Forecast by Ben Matson (issued Friday 22nd September)

Features of the Forecast (tl;dr)

• Small swells for the forseeable futue
• Best conditions Sun and Tues with generally light offshore winds
• Better swell potential later next week/weekend

Recap

Small swells and generally average conditions Thursday becoming clean today with offshore winds. 

This weekend (Sep 23 - 24)

We’ve got a couple of small swells expected to impact the region over the weekend but they’re too small in size and west in direction to have a positive impact on the South Arm.

In addition to easing swell from today, the first new swell will be sourced from unfavourably aligned pre-frontal NW winds way out W/SW of Western Australia earlier this week. The second swell will be extra-long period energy from the huge storm off South Africa over a week ago (which has only just appeared at the Cape du Couedic wave buoy, off Kangaroo Island, with peak swell periods of 20 seconds).

The distant source and poor alignment of these swells means I’m not expecting much size, perhaps 1-2ft sets at exposed beaches, but with very long breaks between waves. 

As for conditions, light winds are expected both days, it’ll trend W’ly on Saturday at times but Sunday should straighten up from the N/NE. As such Sunday will be your best day for a hike to more exposed coasts seeking greater size prospects. 

Next week (Sep 25 onwards)

An active though distant storm track SW of Western Australia over the weekend and into next week will somewhat keep a lid on groundswell size prospects for next week.

We’ll see a series of weak fronts slip south of the state, they’ll have just enough energy to stop the coast from becoming completely flat however it’s unlikely to offer anything inspirational in the surf department. 

If you’re looking for a day to scout for waves, Tuesday and maybe early Wednesday will see the best conditions with light N/NE tending NW winds (Monday will see a front clip the coast, bringing fresh W/SW winds; Wednesday has a late W’ly change on the cards).

The long term, outlook has more size potential associated with a strong frontal passage but it may not be until the weekend that local conditions allow for favourable conditions to settle whilst there’s still some leftover swell on offer. 

Check back Monday for the latest. But until then, be prepared to drive…. and grovel.

Have a great weekend!