thermalben

South swell for the weekend, east swell for next week

South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Friday 13th September)

Best Days: Sun: decent S'ly swell with early light offshore, biggest in Northern NSW (only small in SE Qld). Wed/Thurs: fun E'ly swell though the wind outlook is tricky. Thurs/Fri: interesting long period S'ly groundswell.

Recap: Thursday saw excellent waves in Northern NSW with a SE swell pushing 4-5ft at exposed beaches, and even SE Qld managed good surf with 2ft, almost 2-3ft waves across the outer points, bigger at exposed northern ends. Winds were light offshore ahead of afternoon northerlies. Surf size eased quite a bit overnight, and we’ve seen smaller surf today in the 2-3ft range across Northern NSW, though there’s no sign of the flukey long period S’ly swell (despite the Tweed buoy picking up a jump in peak periods to 22 seconds). Most beaches delivered fun early morning peaks under an early NW breeze, but developing southerly winds have bumped up everywhere through the day. 

Smoky Friday morning lines at Yamba

Small leftover SE peaks at Coolum this morning

Friday lunchtime leftovers at Snapper Rocks

This weekend (Sep 14 - 15)

We’ve got a couple of south swells in store for the weekend, generated by transient fronts through the lower Tasman Sea. The second one is the biggest and best (see below) and will generate the best waves of the weekend on Sunday, though only across Northern NSW.

The general trend will be slowly up through Saturday to 2-3ft+ at south facing beaches south of Byron Bay, with the second south swell expected to reach a peak through Sunday around 4-5ft+.

Surf size will be smaller at beaches not directly exposed to the south, and SE Qld won’t like this swell direction very well, with Sunday likely to see only slow 1ft, maybe 1-2ft waves across the outer Gold Coast point (smaller on the Sunshine Coast) with bigger surf at exposed northern ends and south facing beaches, up to 3ft.

Saturday’s winds look dicey as a southerly change moves up the coast, we’ll see a brief window of morning offshores in Northern NSW so aim for exposed spots early on. However, this front will clear the coast overnight Saturday, leaving us with light offshore winds for Sunday morning and clean conditions area of a freshening northerly after lunch.

So, aim for Sunday morning at your favourite south friendly beach!

Next week (Sep 16 onwards)

Next week just got a whole lot more complex. 

In a addition to a series of interesting long period southerly swells glancing the coast, a small trough will push up the Southern NSW region on Monday, freshening northerly winds across all regions, before the trough stalls off the Mid North Coast into Tuesday, and then broadens a nice E’ly fetch through the central Tasman Sea for a few days. 

Local winds are thus quite difficult to be confident in, because the proximity of the trough to the coast will dictate what happens: we could see fresh southerlies envelop all regions (like they will across Southern NSW), but alternatively, we may see the southerlies confined to a region south from the Mid North Coast, with variable winds further north and even potentially N’ly winds at times in SE Qld. 

In any case, there’s quite a bit of E’ly swell potential from this system and that’s the main thing, as we can always work around pockets of opportunity with the local winds. 

Following on from northerly-affected, easing surf on Monday, Tuesday will deliver building short range S’ly swell in the lee of the change. However, Wednesday and maybe Thursday are where the real E’ly swell potential is, with sets pushing 3-4ft+ at most exposed beaches in Northern NSW, a little smaller north of the border (and direction trending E/SE here). I’ll have a better understanding of local conditions by Monday.

An approaching front from the west will then strengthen northerly winds into Friday as the E’ly swell dissipates - we may should some local NE windswell across the region to finish the working week too - ahead of a return to southerly swell patterns for next weekend and beyond.

As a side note, a complex sub-tropical low will form NE of New Zealand early next week, but despite being quite strong, its swell potential looks to a be a little on the low side because of a poor ridging structure. Its latter stages (mid/late next week) look better aligned but it'll also be further east by this time. I'll take a closer look on Monday. 

Also, just a quick note on the long period S’ly groundswells due next week too - in the absence of any major swell systems (and favourable winds) for next week it’d be worth analysing the potential for these groundswells in fine detail. However, the fact is that it’ll generally be hard to spot ‘em underneath the local energy, so there’s not a lot of point spending much time deliberating about remote, flukey swell sources that - like yesterday afternoon showed - may very well not appear as expected. 

There is one groundswell I really like the look of though, due in around Thurs/Fri, with leading edge swell periods of 21-22+ seconds that could light up south swell magnets with solid though very inconsistent 3-5ft sets. This will be sourced from a deep low and vigorous front SW of Tasmania around Tuesday, so let’s wait and see how the models resolve things over the weekend. 

See you Monday!

Comments

thermalben's picture
thermalben's picture
thermalben commented Saturday, 14 Sep 2019 at 8:10am

New S'ly swell already pushing through Coffs with head high sets (see bloke up and riding, below). Looks pretty smoky though!

adsi's picture
adsi's picture
adsi commented Saturday, 14 Sep 2019 at 5:30pm

Can we expect that southerly swell to have filled in for tomorrow morning Ben ? hanging for a good wave

thermalben's picture
thermalben's picture
thermalben commented Sunday, 15 Sep 2019 at 8:07am

Strong S'ly swells in Coffs breaking quite a fair way outside, especially given we're close to the top of the tide.
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adsi's picture
adsi's picture
adsi commented Sunday, 15 Sep 2019 at 3:09pm

Was quite small south of Cape Byron. 2 ft mostly but turned out pretty fun. How's tomorrow morning looking?

thermalben's picture
thermalben's picture
thermalben commented Sunday, 15 Sep 2019 at 3:31pm

Really? I saw occ 3ft+ sets on the Tweed Coast this morning though the banks were such that (when I was there) all of the surfing was happening on the shorey where it was smaller (though I heard this reversed on the low tide, and the outer bars had good waves).

No change to the outlook for tomorrow at this stage.