South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Monday 10th February)

Best Days: Plenty of good waves most days, becoming sizeable later Friday and into Saturday, easing Sunday, thanks to cyclone swell from TC Uesi. 

Recap: Slowly building E’ly swells were accompanied by generally light variable winds (and a deluge of rain) on Saturday, and Sunday managed to deliver better-than-expected conditions across a few coasts thanks to the dynamic structure of the local trough meandering just off (and occasionally on to) the coast. Some locations did see freshening northerlies through the day though, and wave heights became quite large across the lower Mid North Coast (8ft+ or so) but it was smaller in the north, grading to 5-6ft in Far Northern NSW and 4-5ft across SE Qld (for reference, Sunday reached 10-12ft across the Hunter, Sydney and Illawarra coasts, from the same system). We’ve seen a similar mix today with light winds through the morning at most locations but freshening NE breezes after lunch, and a steady though easing E/SE swell around 3-5ft across SE Qld and 4-6ft throughout Northern NSW. 

Solid lines at Snapper this morning

This week (Feb 11 - 14)

Of the next few days, Tuesday morning is the pick (specifically the morning) as Wednesday may see freshening NE winds. Early Tuesday should see light variable conditions and easing size from today, before afternoon sea breezes freshen from the NE.

A ridge remains in place across the Northern Tasman Sea, midway between the leftover coastal trough that’s now aimed fair and square into Tasmania, and Tropical Cyclone Uesi, which is currently positioned north-west of New Caledonia, tracking slowly south into our swell window.

The resulting E’ly fetch will maintain 3-4ft surf across most coasts into Tuesday though the Mid North Coast may see a few bigger waves. Size will ease a little during the day and then level out into Wednesday around 3ft. Our mid week onshore flow will become more E/NE across SE Qld and NE across Northern NSW so for now it’s generally worth flagging Wednesday as a lay day. Though, early morning may see a few hours of light winds north from Byron into SE Qld thanks to a weak coastal trough. So a quick early surf could be worthwhile in this region.

TC Uesi is an interesting weather system, as it’s been a part of our long range guidance for more than a week now. And the models have been unusually convergent on the broader path, which doesn’t happen at long lead times (especially when there’s another dynamic system within close synoptic proximity). 

TC Uesi will properly enter our swell window on Tuesday morning, and right now it’s looking like it will push south-west towards Northern NSW through the middle part of the week and then travel southwards later this week, almost parallel to the NSW coast, reaching Sydney latitudes over the weekend (which itself is a very unusual occurrence).

The leading edge forerunners of NE swell will arrive across SE Qld on Wednesday, pushing south into Northern NSW by the afternoon but probably not reaching the Mid North Coast until Thursday. However, this will actually be a spread of NE energy from a strong E’ly fetch, rather than sourced from a direct NE fetch, so we need some elasticity on size and timing expectations.

As TC Uesi tracks south, it’ll become perfectly aimed into SE Qld’s swell window from late Wednesday thru’ Thursday, with locations south from the border seeing a delay in the order of about half to almost one day. This will result in a similar timeline delay of peak swell heights (earliest across SE Qld, then the Northern Rivers, then the Mid North Coast). 

Now before getting in projected wave heights, it’s worth pointing out there’s a couple of things I really like about TC Uesi, but a few things I don’t. 

The positives are a steady forward track towards the coast (rather than away), a healthy supporting ridge to the south-east, maintaining a broad fetch on the southern flank of the cyclone, and a path near the coast - to maximise size potential - but not right on the coast (that might destroy the swell lines with unnecessary short range energy).

However, TC Uesi’s forward speed is a tad faster than ideal (and may slightly inhibit a captured fetch scenario), and the fetch length of the core winds is not very long. So when estimating surf size, we have to be careful not to assess the broader system by cherry-picking the stronger characteristics of the inner parts of the cyclone, and then applying this across the entire system.

Additionally, the track will be slightly better aimed towards Southern NSW, and will be more across-the-great-circle-paths relative to SE Qld and Northern NSW. 

Anyway, as for size, SE Qld should see surf size build slowly on Wednesday (3-5ft early morning), then more rapidly into Thursday, peaking later afternoon or perhaps early Friday morning. I’m estimating 8-10ft sets at exposed spots at the height of this swell, and we should see plenty of size across the points too, as the swell direction will be NE tending E/NE (so, shadowed locations will be those facing due south). Wave heights will ease fairly steadily across SE Qld and Far Northern NSW during Friday. 

Across Northern NSW, the delay in the arrival of the peak size will probably result in the Mid North Coast seeing maximum wave heights later Friday. 

As for conditions, Thursday is at risk of freshening E’ly winds though they’ll veer SE as TC Uesi approaches, and will then swing S’ly in its wake (and maybe even SW across a few locations later Friday, mainly SE Qld). Locations north from Byron stand to receive the best conditions from this swell, as the delay in the wind shift will likely create a narrower window of opportunity across southern locations.

So, that’s where things stand at the moment. Let’s take one final pass at things on Wednesday. But, it's looking very promising for some hefty surf with decent conditions. 

This weekend (Feb 15 - 16)

Rapidly easing cyclone swell will occupy the weekend, with the largest waves occuring across the Mid North Coast early Saturday (because it’ll receive this swell later, compared to northern locations).

For the most part, we can expect residual E/NE tending E’ly swells easing from 4-6ft to 3-4ft across most coasts on Saturday though the MNC should see some bigger sets early. 

Also, this size range is more likely across Northern NSW, with slightly smaller surf across SE Qld (specifically the Sunshine Coast).

Residual E’ly swell should maintain 3ft+ surf across most open beaches into Sunday. 

As for conditions, they’re looking pretty good with light variable winds for the most part. 

Giddy up!

Next week (Feb 17 onwards)

A brief reintensification of ex-TC Uesi in the southern Tasman Sea later this weekend may give rise to a short lived but punchy SE swell early next week, but this is still quite some time off. If it eventuates, it’ll mainly influence Southern NSW with the most size, though we should see some fun waves push up into Northern NSW too.

Otherwise, persistent moderate trades south of Fiji this week will maintain background E/NE swells in the 2-3ft+ range for most of next week (probably larger towards the end of the week as the trades muscle up). 

This strengthening of the trade flow will be related to another tropical cyclone that’s expected to develop north of Fiji later this week, and will probably slide between it and Samoa early next week, and so we’ve got some more long range E’ly groundswell potential into the long, long term outlook.

Either way, no shortage of waves for the East Coast. Been a dynamic summer, eh?

See you Wednesday.