South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Wed 14th Dec)

Forecast Summary (tl;dr)

• Fun waves Thurs with a small building E'ly swell and reasonably good winds (best prospects in Northern NSW)
• Building E'ly swell Fri, peaking early Sat, easing thereafter, but showing best across SE Qld
• Large, windy south swell building Fri in Northern NSW, holding Sat/Sun/Mon, easing from Tues
• Smaller surf Wed onwards with light winds

Recap

Small swells have padded out the last few day, Tuesday seeing mainly leftover short range energy whilst today saw the arrival of both a small south and east swell, though mainly across Northern NSW. Winds haven't been too strong so conditions have been workable.

This week (Dec 15 - 16)

The main synoptic feature for the short term period is a developing complex Tasman Low that'll spin up east of Bass Strait overnight, and reach peak intensity on Friday, but actually remain active within our swell window until next Wednesday.

That's right, we're looking at a week of waves from a single swell source.

However, Thursday will see smaller swells from a predominately different source. I've been discussing a sub-tropical low south of Fiji for the last week or so, and it's generated a nice E'ly groundswell that will build slowly through Thursday and Friday towards a Saturday peak, but only Thursday will allow this swell - albeit on the smaller, upwards phase of the event - to be properly seen across the coast in relative isolation.

The models are currently undercalling this event (just 1-2ft); I think we'll see early 2-3ft sets out of the east however I am a little cautious on SE Qld's size prospects as it appears that the building E'ly we've seen today has been focused towards Northern NSW. So keep your expectations in check north of the border.

In any case, winds may be a little funky, as a weak ridge pushes in behind a trough just to our north-east. This will steer SE winds around to the E, though they should be light enough to allow for light morning offshores (more likely on the Gold Coast than Sunshine Coast).

In Northern NSW, this E'ly swell should build from 2-3ft to 3-4ft throughout the day, but we'll also see some new S'ly swell pushing across the region through the day, of a similar size and trend. Conditions should be generally OK across much of the Mid North Coast and the Northern Rivers with a weak synoptic flow resulting in light variable winds and sea breezes.

Friday will then see the E'ly swell ramp up a little more, however it'll be overshadowed by a building S'ly swell that'll reach 4-6ft at south facing beaches throughout the day.

An early window of SW winds is possible across some regions - mainly in the north - ahead of developing southerly winds throughout the day. This will confine the best waves to sheltered southern ends and protected points.

SE Qld will pick up only small levels of S'ly swell on Friday, so we'll be relying on the E'ly swell here, which I still think will fall short of the projected size across Northern NSW. Let's peg wave heights in and around the 3-4ft mark for now (possibly undersized early morning), and expect very long breaks between sets, owing to the distant swell source. S'ly tending SE winds will favour the semi-exposed points.

This weekend (Dec 17 - 18)

The E'ly swell is expected to reach a peak on Saturday morning, around 4-5ft+ south of the border and 3-4ft+ across SE Qld, before easing steadily through the weekend. It'll be very inconsistent and best suited towards more exposed coasts than inner, sheltered points.

Regardless, the dominate energy all weekend will be out of the south (in Northern NSW, anyway), with 4-6ft surf expected both days. Fresh SW tending S'ly winds both days will once again favour regional points and protected southern ends.

I'm not initially expecting the S'ly swell to make much of an impact north of the border, especially with a decent E'ly swell in the water, but these priorities may switch on Sunday as the S'ly swell starts to overshadow the fading E'ly swell across SE Qld. Unfortunately, fresh S'ly winds throughout this period won't favour those exposed beaches picking up the most size, so most surfers will have to rely on the small abating E'ly energy at the semi-exposed points.

Next week (Dec 19 onwards)

The Tasman Low will remain active in our swell window up until Wednesday, and as it'll be positioned further east by this time, the resulting swell direction will be more S/SE, which should allow fore a little more size across the sheltered spots. As such we'll see surf all week from this system.

Fresh southerly winds on Monday will gradually ease on Tuesday to become light and variable Wednesday and Thursday before northerlies resume on Friday.

4-6ft surf at south facing beaches (south of Byron) Monday and perhaps early Tuesday should ease to 3-4ft by Wednesday and 2-3ft for Thursday, maybe even Friday if we're lucky.

North of the border can expect a similar swell trend, but with perhaps only half the size, with the upper end of this size range mainly across exposed northern ends and south facing beaches. The points will be smaller again (short version: make the most of Monday and Tuesday - it'll be open beaches Wed/Thurs).

See you Friday!