South-east Queensland and Northern NSW Surf Forecast by Ben Matson (issued Monday 5th July)

SE Qld Forecast Summary (tl;dr)

• Initially strong, though easing E/NE swell from Tuesday thru' Friday
• Generally good winds for the points until Thursday
• Tricky conditions Friday with possible N'lies
• Unsure weekend, looks small Sat but a flukey S'ly swell is possible Sun

Northern NSW Forecast Summary (tl;dr)

• Initially large, easing E/NE swell from Tuesday thru' Friday
• Generally good winds until Thursday
• Small S'ly swell later Tues/Wed, bigger S'ly swell very late Wed, peaking Thurs
• Tricky conditions Friday with possible N'lies
• Fun S'ly swell Sat, flukey S'ly swell Sun

Recap

We've had pumping waves over the last few days, with E/NE swells from the trough block building surf size to 4-6ft across SE Qld by Sunday (a little smaller on Saturday), reaching 6-8ft throughout Northern NSW. Wave heights have held this size today though seem to be slightly easing now. Saturday's winds were generally light though with pockets of northerlies, however moderate SW winds enveloped the region on Sunday, holding today. As such it's been a great run of surf for the regional points.

Currumbin late Monday

Kirra late Monday

This week (July 6 - 9)

The trough block is slowly pushing eastwards under the influence of a regional frontal progression. We've still got 25 - 30kts of reasonably-well aligned E/NE winds in our swell window (for the MId North Coast at least), but the eastwards storm track is detrimental to swell prospects.

However, the fact that the trough block's been in place since last last week somewhat compensates, as the current (easing, retreating) fetch is working on an already active sea state. And, the supporting ridge to the north-east stretches out into the South Pacific, and should remain active for another 24-36 hours (albeit much weaker in strength. 

As such we'll see surf size ease over the coming days but it should still be pretty punchy on Tuesday. Size wise, I'm not going to change Friday's prediction, which for Northern NSW is 4-6ft on Tuesday, 3-5ft Wednesday and 2-3ft+ Thursday, then 2-3ft Friday. Expect the upper end of this size range across the Mid North Coast and slightly smaller wave heights in the Far North.

Because the main fetch is best aimed  towards southern locations, SE Qld will come in a little smaller all week - probably knock a foot off these estimates for the Gold Coast, maybe 1-2ft less along the Sunshine Coast.

As for conditions, they look pretty good for the points until Thursday afternoon. The broadscale frontal system crossing through the Tasman has swung the synoptic wind to the SW and a building ridge along the Qld coast will anchor in a S'ly flow north from Ballina - though no major strength is expected. 

A developing trough along the coast on Friday is currently modeled to bring about a period of northerly winds, which could get quite gusty. But that's still a few days away, I'll have more details on Wednesday. 

Also! We have some south swell on the way this week, but only for Northern NSW. 

Gusty SW winds exiting eastern Bass Strait today will kick up a small south swell for Tuesday afternoon (2-3ft south facing beaches south of Byron, hardly noticeable) ahead of a stronger south swell building later Wednesday (lower Mid North Coast), sourced from a strong parent low/front combo below Tasmania today. 

This swell looks to peak on Thursday with 4-5ft sets at south facing beaches south of Byron, smaller elsewhere. SE Qld's south swell magnets and exposed northern ends may see some stray 2-3ft sets but it'll generally bypass most of this region. 

Of course, expect smaller surf at beaches not directly exposed to the south.

A strong polar much further south (on Tuesday) should then generate a smaller S/SE swell for late Friday and Saturday in the 2-3ft+ range at south swell magnets. 

This weekend (July 10-11)

As mentioned above, we've got some underlying long range S/SE groundswell for Northern NSW's south swell magnets on Saturday, in the 2-3ft+ range. It'll be inconsistent but should provide some fun waves. 

But, making the surf outlook a little difficult is a small Tasman Low expected to form off the coast on Friday, along the trough line. Current model guidance suggests the strongest flanks will be its northern (i.e. W'ly winds) and south-eastern (i.e. E/NE winds), all of which will be aimed generally away from Nouthern NSW. 

However, current projections are that the low will remain slow moving, and we often see a small spread of acute S'ly swell fill back into the coast from W'ly gales off Southern NSW, as long as there's at least a slight southerly component in the fetch. So, right now I'm hedging my bets that we may see an interesting flush of south swell on Sunday - but probably just a handful of reliable south swell magnets. 

I'll have more on that in Wednesday's update. 

Next week (July 12 onwards)

Long range guidance is suggesting a broad zonal flow across the mid-latitudes next week, which suggests a stream of winteresque fronts throughout SE Australia, but not linked to parent polar lows - which could result in only short, brief southerly fetches within our south swell window.

This doesn't necessarly suggest a poor surf outlook, but the flukey nature of these kinds of weather patterns (relative to our swell window) means that the extended forecast outlook has only low confidence right now.

So, make the most of what you see right now!

See you Wednesday.