Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Nov 22 )

Forecast Summary (tl;dr)

• Chunky E to ESE swell Mon, with fresh onshore winds expected
• Chunky E'ly swell Tues with onshore winds easing- keep tabs on local winds due to small low
• E'ly swell over-lapped by building NE swell Wed PM, peaking Thurs, easing Fri
• Large S swell on the cards for Sat, with fresh S to SSE winds
• S swell tending SSE on Sun, with S to SSE winds easing, surf easing Mon
• Looks like a quiet period ahead for most of next week, stay tuned for revisions

Recap

The weekend was a game of two halves with small surf Sat, marred by S’ly winds and mostly below 2ft. Sunday started small, but as a trough wound up off the Mid North Coast an E’ly infeed generated rising surf with size building into the 3-5ft range and onshore SSE to ESE winds. It was mostly unrideable at exposed coasts, with more sheltered spots seeing 3ft surf for the keen.  Onshore winds from the same direction have continued into today with more unruly 3-4ft surf on offer. A few peaky, semi-sheltered options are on offer for those who aren’t too fussy when it comes to conditions. 

This week (Nov 22-26)

Our current unstable, stormy pattern is being driven by a peanut-shaped high straddling Tasmania, and multiple troughs of low pressure, stretching from the interior of NSW, out to the Mid North Coast and South Pacific near New Zealand’s North Island. Given the dynamic fluidity of this troughy pattern- this past weekend’s trough ended upon the Mid North Coast instead of the South Coast- we’ll still need some wriggle room even in the short term f/cast.

The crux of the uncertainty comes down to the small, surface low which has formed in the trough line off the Mid North Coast overnight.

That small low is expected to retrograde in a SW direction back to the coast through tomorrow. Surf from the E, generated by winds infeeding into the trough/low should hold short period surf in the 3-5ft range, a notch up on size today. Winds will generally be from the SE/E, with the caveat that if the small low tracks further S than f/cast we could see a more SW/S flow around the western flank of the low. This is more likely on the Southern parts of the Mid North Coast, possibly extending down to the Hunter in the a’noon. Keep a weather eye on local winds.

E’ly swell from the close range source eases into Wed, as the small low dissipates and the infeeding fetch winds down. That sees surf in the 3-4ft range, winding back into the 3ft range during the day. With high pressure moving out into the Tasman, we’ll start to see winds rotating counter-clockwise around to the NE during Wed and freshening.

Those N’ly winds extend into Thurs, though with some question marks over strength as a another complex troughy area drifts over the area. Expect light winds in the morning, freshening during the day and with a small signal of ENE/NE windswell overlapping the dying E swell signal. Nothing amazing but the active sea state means it’s unlikely surf will drop below 2-3ft during the day, although quality will remain on the low end of the scale.

The end of the working week sees N’ly winds through the morning before a major S’ly change kicks in during the a’noon. This change is a result of a major trough line forming in the Tasman as an interior trough exits the Coast. 

This trough is expected to exit the South Coast and form a long SSE  angled fetch as it becomes cradled by a large high moving through the Bight. A pretty classic set-up. On current modelling, Fri looks to be NE windswell in the 3-4ft range, with quality determined by the timing of the change. There’s likely a window of cleaner surf as winds swing NW before the change. 

This weekend (Nov 27-28)

The weekend will be dominated by fresh S’ly quarter winds and large swell as the trough forms a small low and the large high tightens the pressure gradient through a large area of Central and Southern Tasman Sea. Sat is likely to see a steep increase in S swell, generated by the proximate fetch of gales to the Southern NSW Coast. With fresh S to SSE winds you’ll need to seek protection, which will entail sacrificing size. This will be a substantial S swell with size likely in the 6-8ft range at S exposed breaks, possibly a bigger 10ft at the more exposed locations, depending on how the windspeeds end up in the fetch.

Winds remain from the SSE on Sun, but should moderate through the a’noon as the trough system dissipates and the cradling high slips away towards New Zealand. Swell from the deeper SSE fetch sees a slightly better angled swell on Sun, but you’ll still need to sacrifice size at most spots to get out of the wind. Expect size in the 6ft range, easing back during the day. 

Next week (Nov29) and beyond

The trend is down from Mon, as the weekends swell event rolls off on size, leaving leftover swell from the SSE in the 3-4ft range, easing further during the day, and a lighter NE flow which may tend to morning land breezes. 

A weak, troughy pattern then occupies the Tasman, leading to a week of light winds and weak swells. 

Frontal systems tracking through the Southern Ocean get shunted southwards next week with zonal fetches, leading to a few minor S swell trains possible through Tues/Wed. We’ll recheck that on Wed, but at this stage we are looking at marginal 2ft surf at the most reliable magnets.

Other than that, looks like a quiet period through most of next week.

There’s some model interest in yet another trough through the interior approaching the coast towards the end of next week which offers both the potential for a NE infeed into the end of the week and a swell event if the low moves offshore.

Both of those events are too far into the future to have any confidence in with such an unstable synoptic pattern.

Best bet is to check back Wed and we’ll take a fresh look at the upcoming synoptics.

See ya then.