South Australian Surf Forecast by Craig Brokensha (issued Wednesday December 20th)

Best Days: Today Mid Coast, South Coast for the keen early Saturday morning

Features of the Forecast (tl;dr)

• Easing W/SW-SW swell tomorrow with strong SE tending S/SE winds
• Poor S/SE windswell for the coming days, easing Sat
• Moderate SE winds, freshening from the S/SE Fri
• Variable winds Sat AM, strengthening from the S through the day
• Strong S-S/SE tending S/SW winds Sun
• Strong S/SW winds Mon, easing a little Tue
• Moderate sized SW groundswell building Mon PM, easing Tue, with a moderate sized S windswell in the mix
• Smaller Wed with S winds
• Possible light E/SE winds Thu AM

Recap

Our moderate + sized W/SW-SW swell filled in through yesterday though the incoming tide filled up the Mid Coast as winds strengthened, creating less than idealistic conditions. Later in the day, conditions improved a little but this morning provided the best surf with cleaner conditions and fun 1-2ft sets.

The South Coast has been a mess with the size building into yesterday afternoon before starting to ease today.

Good sets this morning

This week and next (Dec 21 - 29)

The best swell of the period has unfortunately now peaked, with easing surf due in the gulf over the coming days, tiny and only for beginners tomorrow.

The South Coast will fall under a relentless pattern of poor, strong S/SE-SE winds along with localised levels of windswell. Water temps will also drop thanks to localised upwelling off the South East.

The current pattern will be thanks to persistent high pressure setting up camp south-west of us, squeezed by a stationary inland trough. All linked to a + Southern Annular Mode event.

The squeezing of the high on its north-eastern flank will bring strong SE tending S/SE winds tomorrow, lighter Friday morning but not light enough to provide anything worth chasing.

Our possible more variable W winds on Saturday morning look less likely, with a more variable breeze in general due, possibly light onshore. This will be with a new mid-period S/SW swell generated by healthy polar frontal activity.

Sets to 2-3ft are due across Middleton, flat on the Mid Coast, then easing Sunday as winds strengthen from the S again as the next high moves in. With the poor outlook it's worth chasing a quick surf early Saturday but lower the expectations.

Sunday morning's poor S winds will shift S/SW into the afternoon and then hold Monday, whipping up some tiny but unsurfable S/SW windswell across the Mid Coast.

These winds will persist into Tuesday before finally weakening Wednesday, all thanks to the inland trough to our east broadening into a low. This is the reason winds will tilt back to the S/SW, and at the same time they'll wreck a moderate sized groundswell due into Monday/Tuesday.

The source of the groundswell will be an intensification in the stream of frontal activity moving under the country, with a low due to generate a fetch of W/SW gales over the coming days (above left).

Sets to 4ft are due across Middleton Monday afternoon, easing Tuesday with tiny waves on the Mid Coast.

Longer term there might be a temporary window of lighter E/SE winds on Thursday morning but without any major swell before strong S/SE winds kick back in.

All in all not great at all.