South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Wednesday 11th March)

Best Days: Entire period: windy waves at the points in SE Qld and Far Northern NSW. Could become sizeable mid-late next week.

Recap: Overall, it's been pretty windy in the north with 3-5ft of SE swell across the Sunshine Coast, 3-4ft on the Gold Coast and then slightly smaller surf south from Byron Bay. Tuesday and Wednesday also saw a decent SE groundswell across Northern NSW though wave heights cane in a little under expectations. Winds have been lighter south of Yamba though still out of the southern quadrant.

Empty Greenmount Wednesday morning

Snapper looking fat but fun early Wednesday

This week (Mar 12 - 13)

Looks like a whole week of continuing windy weather ahead for SE Qld and Far Northern NSW. 

A broad ridge through the Tasman Sea extends back quite a reasonable distance towards New Zealand longitudes, and although not perfectly aligned for our region, will maintain plenty of SE swell for the rest of the week.

With the fetch angled best towards the Sunshine Coast, we’ll see the most size here (but also the most wind), where exposed beaches should see occasional 4-5ft sets on Thursday, easing a touch through Friday. Surf size will then become incrementally smaller as you travel south from the Gold Coast.

Of course, with these conditions only the sheltered points will have anything worthwhile so you’ll need to work around the large tidal range each day. 

South from Yamba, and with no other major swell sources on offer - except a small S’ly swell that’ll glance the coast on Friday - we’ll see a slightly smaller, slightly less bumpy version of what’s happening up north. Most regions south from Coffs should pick up a few hours of light SW winds through the mornings, but overall it’s looking a little average - but workable if you’re keen. 

This weekend (Mar 14 - 15)

We’ve got two main synoptic features for the weekend - a gusty southerly change on Sunday in Northern NSW, and a large tropical cyclone in the north-eastern Coral Sea, that’ll concurrently strengthen southerly winds across northern coasts, also on Sunday. 

Saturday will see a low point in both surf size and also wind strength. The Mid North Coast should be light and variable all day, but as you head north from Yamba, we’ll be under the synoptic influence of the supporting ridge south of the developing tropical cyclone. So, this will create moderate to fresh SE winds, but with windows of lighter S/SW winds early. 

Expect 3ft+ sets across SE Qld and Far Northern NSW, with smaller surf as you head south (the Mid North Coast may just be a couple of feet of residual swell). 

Surf size will slowly rebuild on Sunday as the wind strengthens but quality will be very low and only sheltered locations will have anything rideable (and they’ll be quite small at first thanks to the predominant S’ly swell direction). 

Model guidance is showing a small N’ly swell across the coast on Sunday - 0.5m at 14.6 seconds at the Gold Coast - but I’m not particularly confident on the source of this right now - the cyclone develops in a rare part of the swell window and tracks away from the coast, so any energy we see will be glancing sideband energy at best. 

But, by Friday we’ll have a firmer dataset to evaluate, so we’ll be able to see if there’s any potential from the northern swell window.

Either way, it’s going to be bloody windy. 

Next week (Mar 16 onwards)

Jeez, next week is looking super complex. 

A Tasman Low in the central/Southern Tasman Sea on Sunday and Monday looks to be slightly off-axis for Northern NSW’s swell window, but I’ll assess this again on Friday for potential. 

Otherwise, the main focus for next week’s forecast centres around the aforementioned large tropical cyclone that is expected to have (by this time) tracked rapidly SE through the Coral Sea, taking up residence off the North Island of New Zealand as an extra-tropical low pressure system around Monday. 

Individual synoptic snapshots look very impressive with regards to E’ly swell potential for Northern NSW and SE Qld early next week, but the fact of the matter is that this cyclone is expected to travel too fast (during its initial phase in the Coral Sea) to generate an exceptional swell event for our region, that corresponds with the synoptics.

But, once this system stalls near New Zealand around Monday, things look much different (see below). Though - as expected - there have been a lot of model revisions over the last few days, and we’ll see further changes over the coming days - so it’s too early to pin down anything specific. 

So, let’s paint in long, broad brushstrokes for now.

To begin with, there’s enough strength and depth in the weekend’s preliminary infeed (south of the cyclone) to generate a good 4-6ft of E’ly and SE swells (yes, from several sources) for the first few days of next week, in addition to whatever local windswell rears its head from the local fetch developing Sunday and holding through Monday. 

If we’re to believe the latest model runs, the extra-tropical developments near New Zealand around Monday should give rise to a powerful E’ly groundswell around Wednesday that should push size up into the 6-8ft range, may even higher, holding through Thursday. 

There's a good baseline to work with for all future forecasts.

To provide a little more detail, the current (modeled) strength of the core winds around this ex-TC are likely to be in excess of 50kts across a broad swathe, so it’s easy to assume we could be looking at much significantly more size - but I’m still very dubious on the evolution of this system, relative to surf potential.

Its proximity to New Zealand is also of considerable concern, as it’s already going to bisect a healthy percentage of the broad scale fetch and any small eastward shift in the position of this low could completely wipe out ALL of its swell potential. So, nothing is assured at all from this system, no matter how sexy the WAMS look right now.

Let’s take a closer look on Friday.

See you then!