South Australian Forecast by Craig Brokensha (issued Wednesday July 16th)

Best Days: South Coast today and tomorrow morning, Mid Coast early Friday, South Coast Friday, South Coast Saturday morning, South Coast Sunday (Mid Coast through the morning), South Coast Monday and Tuesday

Features of the Forecast (tl;dr)

• Large SW groundswell kicking later today, peaking tomorrow morning with W/NW tending SW winds down South, fresh NW tending variable on the Mid through the AM
• Large W/SW groundswell for Fri AM, easing with freshening N/NW winds down South, light-mod N/NE-NE tending fresh N/NW on the Mid
• Large, reinforcing W/SW groundswell Sat with strong N/NW tending NW then W/NW winds
• Easing surf down South Sun, holding on the Mid with early variable winds on the Mid, tending N through the day, N/NW down South
• Easing surf Mon with strong N/NE winds
• Smaller Tue with mod-fresh N/NW winds
• Large W/SW groundswell likely Wed with mod-fresh N/NE tending N/NW winds

Recap

The Mid offered a fun, clean 2ft wave yesterday morning with early clear conditions before fog rolled in while the South Coast came in a bit lumpy though still solid and to 3ft+.

This morning the swell has backed off to a weaker 2ft to occasionally 3ft across Middleton with a fresh offshore wind, tiny and wind affected across the Mid Coast.

Later today a mix of new mid-period and groundswell are due to show across both coasts as winds strengthen from the N/NW.

This week and weekend (Jul 17 - 20)

Up, up, up.

From this afternoon through the coming days we’re expected to see the swell increasing in both size and power as a strong progression of Southern Ocean storms produces multiple pulses of large groundswell.

This afternoon’s increase will arrive out of the SW, generated by a strong low that spawned off a strong Southern Ocean frontal progression that was positioned around the Heard Island region earlier this week.

This should provide good 4-5ft+ sets across Middleton tomorrow morning, possibly easing a touch through the day with 1-2ft sets across the Mid Coast.

As touched on in Monday’s notes, winds are looking dicey as a weak SW change moves through around dawn, but we’re now looking at an increased likelihood of morning W/NW winds across the South Coast, shifting weak SW into the afternoon and dawn NW winds on the Mid, easing and becoming variable through the morning.

Friday is a much better surf day though as our larger W/SW groundswell fills in tomorrow evening, peaking through the morning.

This swell is being generated by a secondary, slightly stronger low pushing in, under Western Australia today, with it sitting a touch more north in latitude, generating a more westerly angled groundswell.

The Mid Coast should see stronger 2-3ft waves through Friday, while Middleton looks to come in at 6ft on the sets, easing a touch through the day.

A third and final pulse of large W/SW groundswell is then due on Saturday, produced by a third frontal system pushing in right on the tail of the current low passing under WA, with severe-gale W/NW winds moving on top of an active sea state.

This should maintain 2-3ft surf on the Mid Coast with the South Coast holding 4-6ft, easing slowly from a similar size Sunday inside the gulf and down from 4-5ft+ across Middleton.

Conditions will be best for the South Coast this period with the Mid offering windows of lighter winds but still less than perfect conditions. Moderate N/NW winds are due to freshen into the afternoon Friday, with the Mid seeing a window of early, lighter N/NE-NE winds.

Saturday will see strengthening N/NW tending NW then W/NW winds as the final swell producing front moves through, with the South Coast being best through the morning, while come Sunday, the South Coast looks great with a light N/NW offshore. The Mid Coast looks to see variable tending N/NE-N winds, with lumpy surf for the keen, though with the size it’ll be worth a paddle.

Moving into next week and strengthening N/NE winds Monday with easing levels of swell from the weekend will favour the South Coast, with weaker N/NW breezes due Tuesday.

We may see a signifcant, strengthening mid-latitude low bringing some new, large W/SW swell later in the day but more so Wednesday, though we’ll review this Friday.