North vs south.

Or is it south vs east..?

While surfers from Sydney's Northern and Eastern Beaches lamented at the large and mostly wasted southerly swell lines over the past week, Cronulla and South Coast surfers rejoiced as long-dormant reefs roared to life.

Further north of Sydney, select pointbreaks offered moments of magic, but it was slim pickings north of the Queensland border.

Looking at the charts for next week and it appears we'll see a flip back to the east, as a strong, slow moving low pressure system deepens just north of New Zealand's North Island.

The catalyst for this low will be a tropical depression sitting in the Coral Sea, drifting slowly south-east while deepening over the weekend. A pool of cold air will be advected north across New Zealand, feeding into the tropical air mass, resuting in the rapid deepening and intensification of the low.

Importantly for swell, this hybrid low will be cradled by a high pressure system sliding under New Zealand, tightening pressure gradients further on its south-western flank, aimed back towards the East Coast.

The low looks to be best aligned towards the NSW North Coast and south-east Queensland, but that's not to say the Sydney region will miss out.

However, locations further south of Sydney and deeper towards Tasmania will see a relative size reduction as they fall within New Zealand's North Island swell shadow.

Great fetch aimed towards the East Coast. Also note the large swell generator for Tahiti, further east

The great thing about the development of this low, is that a mid-latitude frontal progression will move across us right when the swell is due to start building, bringing clean conditions and offshore, south-west winds in the mornings.

Northern NSW should see an initial kick in large E/SE groundswell on Wednesday morning, ahead of a secondary pulse through the afternoon, holding into Thursday. The Sydney region will build strongly into Wednesday afternoon, then easing slowly Thursday from an early morning peak.

Size-wise, we're looking at a peak to the 6-8ft range across northern NSW and south-east Queensland, grading smaller and coming in more towards 4-6ft around Sydney. Morning, offshore W/SW-SW breezes will create great conditions on Wednesday, shifting S-S/SE into the afternoon, with Thursday due to play out similar.

The swell will have a bit of longevity with the low forecast to hold north of the North Island while slowly weakening through the middle of next week. This will see the size slowly abating through Friday and then more noticeably next Saturday and Sunday. Winds look to swing more NW into Friday, straightening out from the W again on the weekend as the next front pushes through.

And yes, with a return to an easterly influence we'll also see a return to rain after two weeks of clear blue skies. This could happen as soon as this weekend so keep an eye on weather forecasts.

Following this event there's the possibility of a secondary low forming in the Tasman Sea late in the month. It's worth noting that swell, however we've got plenty to look at in the interim.