Incoming from the east
Just as the East Coast was settling into winter and a belated pattern of south swells, the Coral Sea has begun to twitch and tremble.
A system more reminiscent of late summer or autumn is currently taking shape with a large high pressure system enveloping the whole Tasman Sea and a broad field of easterly winds forecast to blow across its northern flank. It’s a classic trade wind set up, more often seen through the warmer months delivering mid-range east swell to SE QLD and Northern NSW.
Those coasts could’ve expected similar returns from this system, except that on Friday an easterly dip will form south of New Caledonia (see image below) which will increase the pressure gradient in the wind field and push core wind speeds above 40 knots.
The strongest winds are aimed towards SE QLD, which will be the biggest beneficiary (in terms of size) from this swell, however the increased wind speed is just one notable factor of what’s shaping up to be a favourable system.
The sheer size of the wind field - which will occupy the SE corner of the Coral Sea and stretch out into the South Pacific - and its distance off the coast will ensure that this is a widespread and extended swell event. Queensland and northern NSW will get the most size, but the swell will be felt right down the NSW coast and as far south as the east coast of Tasmania.
Between Friday and Sunday, the easterly dip will also retrograde - that is, move west towards the Australian mainland - thereby creating a captured fetch which will prolong the period of strong winds blowing on the growing swell and increase wave size on the coast
So, timing and size?
Being closer to the action, Queensland and Northern NSW will be the first to receive swell with the first flush of easterly trade swell beginning this weekend, coming in around 4ft, however by late Sunday the period will climb over 10 seconds and the swell will muscle up to approx 5-6ft. The size will steadily climb through Monday, peaking on Tuesday at around 6ft+, though it’d be wise to pace yourself as there’ll be a long wag in the swell’s tail as the swell drops slowly, with even Friday expecting 3-5ft waves on the Gold Coast.
Yep, a full working week of east swell. How long has it been since that's happened?
Coastlines further south down the NSW coast can expect a later arrival with the first tendrils of swell hitting Monday morning (earlier to the north, later to the south) and then a similar upwards trend peaking through Tuesday. The further south, the more north the swell will be. In Sydney it will strike from the east-northeast.
Monday will climb from 3ft to 5ft, with Tuesday and Wednesday coming in around 5-6ft, and then a slow taper through the back half of the week. With swell periods around 12 seconds, it’s likely that some exposed bommies will magnify the energy and come in a bit above those predictions.
And lastly, winds, because a good swell with bad winds isn't a good swell at all.
Queensland and Northern NSW will see south-east onshores through the weekend and early part of the swell, fortunately improving to light southerlies on Monday and Tuesday, so the outer points will be bumpy but inner points silky. Wednesday and Thursday are looking like a mix of NW and SW, before a return to light southerlies on Friday.
Sydney should see an early offshore land breeze on Monday morning, shifting towards the north through the day before a westerly change hits on Tuesday, blowing first north-west then settling into southwest through Wednesday and Thursday.
There'll be various takes on the above scenarios depending on where you're located on the coast, and keep in mind we're a week out so accuracy of the local wind forecast is still loose.
Check your forecast in the links below or keep track of changes in the comments.