South Australian Surf Forecast by Craig Brokensha (issued Friday September 1st)

Best Days: Both coasts today, South Coast on the weekend, Tuesday afternoon both regions, early Wednesday Mid Coast, South Coast all day Wednesday

Features of the Forecast (tl;dr)

• Slight drop in swell Sat with N/NE-NE tending variable winds (E/NE in the AM on the Mid)
• Smaller easing surf Sun with gusty N/NE-NE winds, tending N/NE and easing
• Mod-large W/SW groundswell building later Mon, peaking Tue AM with gusty W/NW tending W/SW winds Mon
• Large W/SW swell building Tue PM, easing Wed with gusty but easing W/NW-W/SW winds Tue
• Moderate N/NE tending fresh N/NW winds Wed
• Gusty W/SW winds on Thu with some new, building W/SW swell, peaking Fri with N winds

Recap

There was a window of clean conditions across the South Coast yesterday morning with a peaky, weak swell to 2-3ft, deteriorating through the day with an onshore change and increase in swell. The Mid was poor and weak all day, but today we've got our peak in mid-period SW swell with glassy 1.5ft+ waves on the magnets and lumpy 4ft+ surf across the South Coast.

Sea breezes are only due to be weak across both coasts so there'll be a fun wave all day.

Fun Mid Coast waves today

This weekend and next week (Sep 2 - 8)

Today's swell will ease slowly over the weekend as the some slightly stronger period energy fills in tonight, generated by the earlier stages of the swell producing frontal system.

Middleton should be around and inconsistent 3-4ft, easing slightly later and then down from 3ft on the sets Sunday morning (mostly 2-3ft).

The Mid Coast will lose it's surfable size and back off to 1ft+ tomorrow, tiny Sunday.

Local winds look favourable again tomorrow with an E/NE offshore on the Mid Coast and N/NE-NE winds down South, becoming variable into the afternoon.

Sunday looks clean all day across most breaks with a fresh N/NE-NE breeze, easing and holding from the N/NE into the afternoon.

Monday will be a lay day with a low point in swell during the morning under early, gusty NW winds ahead of W/SW change before lunch.

Into the afternoon we're likely to see an increase in size on the Mid Coast as a new, moderate to large, long-period W/SW groundswell arrives, though Tuesday should reveal the most size as a larger increase fills in.

The source of these swells is strong, back to back frontal systems pushing in from the west-southwest of Western Australia.

The first system will be the strongest but the most distant, with a great fetch of gale to near severe-gale W/SW winds currently projecting east through our medium-long-range swell window.

This storm will weaken on approach to Western Australia, generating a moderate to large W/SW groundswell that might kick to 2ft late on the Mid Coast Monday but peak Tuesday to 2-3ft.

Middleton should see inconsistent 3-5ft waves on Tuesday morning when it peaks, but both regions will see a more consistent, larger mid-period W/SW swell building through the day, generated by a secondary front firing up on the tail of the first.

An additional fetch of strong to gale-force W/SW winds will be projected up and under Western Australia, through the Bight Monday, slowing a touch while moving in and across us Tuesday.

A late pulse to 3-4ft is likely on the Mid Coast, easing from 3ft+ Wednesday with Middleton kicking to 5-6ft, easing from a similar size Wednesday morning.

Fresh but easing W/NW tending W/SW winds are due on Tuesday, with workable waves all day in protected spots down South, best later on the Mid, while Wednesday will be wind affected in the gulf but great down South. A N/NE tending fresh N/NW breeze is due, best at dawn on the Mid Coast.

Weaker, trailing mid-latitude frontal activity should generate some reinforcing mid-period W/SW swell later week though with a gusty W/SW change Thursday, possibly cleaner Friday. We'll have a closer look at this on Monday though.