South Australian forecast by Craig Brokensha (issued Friday March 21st)

Best Days: Both coasts today ahead of sea breezes, both coasts tomorrow morning, Mid Coast Sunday for a small wave, South Coast Sunday morning

Features of the Forecast (tl;dr)

• Easing surf tomorrow with light, local offshore winds ahead of strengthening S/SE winds
• Moderate + SW groundswell building rapidly Sun with E/NE-NE tending S/SE winds down South, E/SE tending SW on the Mid (possibly S/SE later)
• Easing swell Mon with fresh S/SE winds
• Smaller Tue with E winds in the AM, back to the S/SE into the PM
• New moderate sized, inconsistent SW groundswell for Wed, peaking through the middle of the day/afternoon with gusty S/SE winds
• Easing swell Thu with mod-fresh E/SE-SE tending S/SE winds
• Smaller Fri with possibly E/NE morning winds

Recap

The South Coast offered great waves into yesterday morning with easing 4ft sets from the SSW under strengthening offshore winds that then eased ahead of an evening change. 

The Mid Coast became choppy through the morning before improving into the afternoon while today, our new W/SW swell has started to fill in with infrequent 1-2ft sets under a nice offshore wind.

The South Coast saw improving conditions this morning with a lighter E-NE wind developing along with building sets to 3-4ft. We should see the building swell through today peaking this afternoon along with sea breezes, cleaning up later inside the gulf but with an unfavourable, big high tide.

Cracker conditions yesterday morning

This weekend and next week (Mar 22 - 28)

Today’s swell will start to ease back through tomorrow but conditions look great for all locations with a light, local offshore breeze and easing 1-2ft sets across the Mid Coast, 3ft+ down South.

A trough will bring strengthening S/SE winds into the afternoon while Sunday should see winds ease and tend back to the E/NE-NE down South, E/SE on the Mid coast, along with our stronger pulse of SW groundswell.

The source is a deepening low currently south of Western Australia, with a great fetch of gale to severe-gale W/SW winds due to generated through our south-western swell window today before weakening this evening,.

The swell will build rapidly from dawn with Middleton due to reach 4-5ft+ with 1-2ft sets likely on the Mid Coast on the favourable parts of the tide (undersized early).

Sea breezes will kick in across both coasts though a following trough will likely tend winds S/SE later on the Mid Coast, with Monday seeing fresh S/SE winds continuing as the swell fades from 1-1.5ft inside the gulf, 3-4ft down South.

A slight easing and shift in winds to the E on Tuesday should provide slightly cleaner conditions down South but with smaller surf to 3ft across Middleton, tiny in the 1ft range across the Mid Coast.

Into Wednesday, a new long-range SW groundswell is due, with the source being a strong polar low that formed west of the Heard Island region earlier this week.

A slow moving fetch of severe-gale W’ly winds were projected through our long-range swell window, with the low due to slowly weaken and track east-northeast today and tomorrow, towards Western Australia.

It’ll be inconsistent but the South Coast should see strong 4ft sets off Middleton developing Wednesday with the Mid only coming in at 1-1.5ft.

Unfortunately winds will revert back to the S/SE on Wednesday, spoiling the South Coast with Thursday remaining less than ideal under a fresh E/SE-SE breeze as the swell eases. Friday could be cleaner thanks to a lighter E/NE wind but with smaller, fading surf.

Longer term it looks like high pressure and winds from the south-eastern quadrant will dominate the period, with a return to a summer like pattern. Have a great weekend!