South East Queensland and Northern New South Wales Surf Forecast by Ben Matson (issued Monday 9th March)

Best Days: Second half of the week onwards (Wed thru' Sun) should have fun small waves at semi-exposed points under a slowly building trade swell. Stronger E'ly swell for late Mon/Tues.

Recap: A second south swell pushed across the NSW coast on Saturday, surprisingly coming in bigger than forecast in southern NSW (6-8ft south facing beaches, and 10-12ft+ at offshore bombies), but a little smaller than forecast across much of Northern NSW and SE Qld (the latter of which was expected to be very small anyway). This event eased from Sunday and further into today, leaving most locations with very small waves to start the working week.

Next week (Mar 10 - 13)

No major changes to the forecast for the rest of this week as issued last Friday.

We’re currently at the low point of the swell cycle; the trades are slowly starting to muscle up south and west of New Caledonia, and this will incrementally build a trade swell about the region over the coming days, biggest north of Byron. 

A ridge across the Queensland coast will maintain moderate to (by the second half of the week) fresh SE winds, although pockets of light S/SW winds are likely early mornings at the usual haunts. 

As for size, expect a slowl upwards trend from Tuesday onwards, towards a peak on Friday afernoon in the 3-4ft range across open Gold Coast beaches (a little smaller on the points) with bigger sets on the Sunshine Coast (3-5ft, but again smaller on the points - and even more so at very sheltered spots like Noosa).

However, the open beaches picking up the most size will be wind affected so the sheltered points will certainly offer the best conditions. 

As a side note: (re: WSL event) - the contest site at Snapper Rocks usually performs as well as an open beach under these tradeswell events, so we should see a slow building trend from 1-2ft Tuesday to 2-3ft throughout Wednesday, a little bigger into Thursday and then somewhere around 3ft to maybe 4ft throughout Friday. Local winds should be OK - the afternoon sou’easter will add in some bumps to the outside section but for the most part the wave faces should be clean. 

South of Byron Bay, this trade swell will taper off in size with increasing southerly latitude, but local winds will be lighter. A southerly change is due throughout Friday which will also bring about a building short range S/SE swell into the afternoon (and more so into Saturday), but no major size or quality is expected from this source. 

This weekend (Mar 14 - 15)

Although we’ve got a pretty serious looking synoptic chart for the next few days, the weekend is expected to mainly consist of similar trade swell as what we’re expecting on Friday.

A second developing Tropical Cyclone in the northern Coral Sea will enhance SE winds through the southern Coral Sea during this time, and several days of building trades further east (i.e. north of New Zealand) should maintain mid-range energy from the east. 

At this stage we’re still looking at somewhere in the 3-5ft range for open beaches across the Sunshine Coast, 3-4ft for the Gold Coast and then slightly smaller surf as you track southwards from Byron Bay. Moderate to fresh SE winds will dominate the region (lighter on the Mid North Coast) so it’ll be a fun weekend of small to moderate sized semi-exposed points.

Is there a chance for an upgrade? Certainly, but it’ll require future model updates to rapidly speed up the development of the second (Coral Sea) Tropical Cyclone, and track it further south than the current E/SE trajectory. The larger Tropical Cyclone (developing near the Solomons right now) is not expected to provide major energy to the coast until next week (read on for more!).

Next week (Mar 16 onwards)

Tropical Cyclones, eh? Amidst much of the hyperbole in recent days, and as suggested in these notes on Friday, it looks like we probably won’t see a major swell event from this system (despite the myriad of colours on the WAM charts). 

What’s unfolding right now is a very complex synoptic pattern across the Tropical South Pacific. However, we’re now getting a firmer grip on the future track of this first Tropical Cyclone developing near the Solomon Islands: initially, its strongest intensification phase will probably occur inside the swell shadow of the South Pacific islands (i.e. Vanuatu, New Caledonia et al), and during that time the strongest flank of the cyclone will be its eastern side (ie W'ly thru' N'ly winds, aimed to the south-east).

The cyclone is then expected to track south, and then south-east, post haste: not a good development for East Coast swell potential (as it’ll be perpendicular to the great circle paths). 

But that doesn’t mean we have to completely write off this system.

Let’s take a look at the synoptics across our swell window for the next few days - on the whole, building trades from about Samoan latitudes through the mainland. This will whip up a small sea-state that will be of great assistance as the cyclone approaches and its supporting ridge to the south tightens further.

However if you assess the supporting ridge to the south in isolation as it develops towards the end of the week - i.e. ignore the cyclone itself and just look at the broader trade flow - there’s a healthy fetch of easterly gales developing to the south between Friday and Saturday (see chart below) as the southward tracking cyclone ridges up against a high east of New Zealand. 

And this is the most likely source of a decent swell event from this entire weather progression. 

At this stage we’re looking at a stronger E’ly trade swell arriving Monday (4ft most open beaches), ahead of an E’ly groundswell pushing through Tuesday (4-5ft) before easing steadily from Wednesday. The more distance source of the swell, plus the easterly swell direction should provide a relatively uniform size distribution to most coasts. It's a real shame the entire system is tracking SE though, as this track will majorly restrict its surf generating potential.

Also, I am discounting the core of the cyclone as having any swell generating potential (for the East Coast), as I don’t think the environment is sufficiently well set up to allow this to contribute significant energy from such a distant source. So really, this swell event will probably just be another super-charged trade swell, mixed in with a healthy percentage of mid-range energy from a more local source (mainly in SE Qld), being the infeed of SE winds into the second developing Tropical Cyclone in the Coral Sea. 

Of course, these surf height estimations are malleable depending on how the second cyclone behaves. There is certainly a reasonable possibility that it could track down the Qld coast and end up being a dominant system for the middle of next week, overshadowing any energy generated by the first cyclone further afield. But we won’t have a grip on those possibilities for quite a few days yet.. so let’s re-evaluate the numbers again on Wednesday.