Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Monday 30th June)

Best Days: Tues/Wed/Thurs: strong S'ly groundswell, biggest Tues/Wed with generally good winds. Fri: plenty of leftover south swell with offshore winds. 

Recap: Tiny waves on Saturday, consisting of leftover (and rapidly fading) southerly groundswell and a meagre NE windswell. Almost completely flat on Sunday with fresh offshore winds. Building S’ly swell today that held 2-3ft at south facing beaches early morning, but is now pushing 4ft and could become a little bigger by the end of the day. Still very small at beaches not open to the south though.

This week (July 1 - July 4)

Looking really good all week, as long as you don’t mind a steady diet of south swell.

As was discussed much of last week, the Long Wave Trough is amplifying across Tasman and New Zealand longitudes, and will result in a prolonged region of strong to gale force S/SW winds stretching from polar latitudes right up into the Tasman Sea.

In essence, this will deliver around four days of strong south swell (with today being Day 1). Wave heights will build further into Tuesday, holding through Wednesday at a similar size ahead of a slow easing trend Thursday. At the peak of the swell (late Tues/Wed) south facing beaches should manage 4-6ft surf, with a few bigger waves in the Hunter. However locations not open to the south will be considerably smaller.

In fact there’s an interesting front/low contained within this pattern that may give a slightly bigger boost to the coast late Wednesday (or possibly overnight into Thursday morning) that the models aren’t picking up very well right now.

A small low is modelled to form well SE of Tasmania (and SW of New Zealand) early tomorrow, before rocketing up through the central Tasman Sea. It’s not aimed very well for the East Coast but the associated kick in swell period - thanks to the fetch working on the pre-existing sea state - could really amplify wave heights at exposed reefs/deepwater locations. However, due to the eastern position of the fetch, it’ll probably create a more noticeable increase along the North Coast than in southern NSW. The timing isn’t great for southern regions either - likely to be overnight. But it will be worth keeping an eye out for.

Throughout this period, conditions should be generally quite good with moderate to fresh W’ly tending SW winds on Tuesday and Wednesday. There is a risk that we’ll see S/SW winds develop on Tuesday afternoon and Wednesday afternoon, and this poses a risk mainly for the Northern Hunter region. By Thursday we’ll be back to light W/NW winds in most areas as the swell begins to ease.

Friday is also looking great with freshening NW winds and slowly easing S’ly swell from Thursday. Another strong front trailing this broad progression (through the Tasman Sea overnight Wednesday/early Thursday) is split between the computer models as to where it’ll strengthen and focus, and at the moment there’s a reasonable chance that the current automated forecast of 2ft surf on Friday could very well be upgraded by a foot or two in future model runs. But I’ll have a closer look at that in Wednesday’s update.

This weekend (July 5-6)

Lots of divergence between the models right now, so we’re going to need a few days before fine tuning the weekend forecast. But in general the overarching theme looks to continue the run of southerly groundswell for the region, from a couple of sources (both distant and near). Overall I’m confident there’ll be some decent waves but let’s take a closer look on Wednesday.

Long term (July 7 onwards)

Again, with divergent model guidance we really can’t speculate too much on next week’s surf however we’re in the midst of a fluid, mobile Long Wave pattern and this certainly tips the balance in favour of a steady stream of southerly swells for the long term. More on this in Wednesday’s forecast notes.