Best days: Friday AM in metro regions, Saturday AM in Margs

Features of the forecast (tl;dr)

• Small leftovers with OK winds at Margs tomorrow morning
• Localised windswell Thur PM for metro regions but onshore
• Easing windswell on Friday with better winds up north
• Inconsistent SW groundswell Sat AM with good winds
• Stormy, severe conditions into the weekend building up early next week

Recap

Tuesday was a fun day up north with 3ft peaks and clean surf all day, while Margs was messy and onshore.

Today was more workable and all regions had fun conditions in the morning, the metro regions saw peaky 2-3ft waves with offshore winds before deteriorating into the afternoon, and Margs had the E/NE winds holding up all day and the groundswell easing from 6 to 4ft. 

This week (Jul 2-4)

There is not much change from the last notes for this week and the weekend other than some improvement for Margs on Saturday, with some leftovers and windswell for the next few days before large, stormy conditions develop into Sunday and next week. 

The WSW groundswell eases through the next few days, and while nothing else major arriver, we have a small and relatively weak low pressure system off the coast with a fetch of westerlies on its northern flank that is producing a localised pulse well aimed for the metro regions. The system pushes onto the coast from tomorrow morning, with the WNW windswell building in the afternoon to 2-3ft, but that will arrive with onshore W/SW winds. 

Margs will be sitting in the eye of the low in the morning and could see light NE/N winds with the leftover groundswell at 3-4ft, before it goes onshore. Mandurah could also see light winds in the morning and leftover 1-2ft waves before the windswell builds but Perth is closer to that northern flank with fresher winds all day. 

As the system moves through and high pressure approaches from the West, on Friday we see improving winds out of the SE for metro regions weakening through the day, but the best timing is in the morning before the windswell eases from 2-3ft. Margs will still see SSW winds from the remnants of the low going fresh to moderate later in the day, before improving on Saturday.

This weekend (Jul 5-6)

Condition should clean up on Saturday morning with the high pressure moving in through the night of Friday, making it a good window of surf well timed with the arrival of a new groundswell. 

As touched on in the last notes, the source is a distant polar low formed south of Madagascar that quickly weakened as it progressed east, so the swell will be inconsistent but should arrive at 6ft+ in Margs, 2ft Mandurah and 1-2ft Perth. 

Into the afternoon we have the arrival of a strong and long frontal progression pushing up against the country under the influence of the Long Wave Trough, and the start of some very raw few days. 

Through Sunday we’ll see strengthening N/NW winds as the first severe front moves in, with a building stormy WNW surf that peaks on Monday more from the south-west. It is a very wild and destructive system and the beaches could see some serious erosion with the strong onshore winds, high water levels and stormy surf.

Next week (Jul 7 onwards)

The next front moves in on Tuesday keeping the winds onshore. These are very dynamic systems and the timing of a possible window of lighter winds depends on how those develop, so we will provide an updated outlook on Friday.