Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Nov 29 )

Forecast Summary (tl;dr)

• Small leftovers from the SE Tues AM, with light winds
• Small, pulsey E swell suitable for a grovel Wed-Fri, with flukey, light winds
• Small increase in S swell Sat PM with S'ly winds
• Stronger S swell Sun with S'ly winds
• Easing surf Mon next week
• More E swell ahead as tropics become active, check back on Wed for revisions

Recap

Lots of energy over the weekend from the south, with winds and swell from that direction as a deep, elongated trough aimed up at NSW. Saturday saw lots of solid swell in the  6ft+ range, bigger 8ft on the Hunter but with fresh S’ly winds the only surfable options were at more protected locations. Swell angled in a little more favourably Sun, with some 6-8ft sets still on offer at S exposed breaks and easing S’ly winds. This morning has seen cleaner conditions with some good quality 4-6ft surf on offer across a wide spread of locations with a much lighter wind regime. 

This week (Nov 29-Dec3)

We’re right up to our neck in a troughy La Nina pattern, which continues on through this week. High pressure is sitting just to the East of Tasmania, with the dissipating remains of the weekend’s trough of low pressure linked to a coastal trough extending up into the sub-tropics. More troughs are expected in the Tasman this week before another long, elongated trough occupies the Tasman, this weekend, in a similar pattern to this last weekend’s trough system. The tropical and sub-tropical South Pacific Convergence Zone is starting to bubble up with a series of depressions which look likely to be surf producers into the medium term. 

In the short run, the trend is down, with the leftover of the current SE swell event running down through tomorrow. Some early sets in the 2-3ft range, drop back into the sub 2ft range through the day. Early light winds then tend to the E/NE during the day.

What follows is a period of small and weak energy from the E as the troughs in the Tasman set up a lazy blocking pattern. A broad but weak tradewind fetch pushes south from the Coral Sea, extending out towards New Caledonia, and looping around a long trough extending from roughly Lord Howe up into the tropics. That will be the primary swell source this week, supplying pulsey, flukey surf in the 2ft range with some subtle ups and downs as wind speeds fluctuate around the trough line.

Expect this regime of grovel worthy small surf at magnets Wed-Fri

Having said that, it’s local winds that will determine a fun surf, and they will be flukey this week, in response to the troughiness. The general pattern will be light and variable E’ly breezes, more N’ly Wed , before tending light E’ly through the a’noon and then light and variable Thurs/Fri. 

This weekend (Dec 4-5)

The upcoming weekend is looking like a watered down version of the one just passed. A cold front feeds into an elongated trough through the Tasman Sea, squeezed by high pressure moving through the Bight. This brings S’ly winds and swell, albeit at a reduced level compared to the current event. 

Saturday is likely to start out small with residual E’ly swell, with S’ly winds kicking in through the day as the trough winds up. There’s still considerable model divergence on the resulting fetch but neither of the major models suggest anything too powerful, so it’s good odds an a’noon increase in S swell from the initial cold front pushing E of Tas will be short period and quite modest; likely up into the 3ft range at S exposed breaks. 

Fresh S’ly winds continue into Sun, possibly SW inshore early for a brief period more likely on the Northern Beaches. The trough is expected to be pushed out into the Tasman as high pressure moves E of Tasmania. That should allow for a broader coverage of S/SSE winds through the Central Tasman, although low windspeeds look to be the main limiting factor for swell generation. We can expect 3-4ft surf at S facing beaches likely easing into the 3ft range during the a’noon. Bigger 4-5ft on the Hunter. 

Next week (Dec6) and beyond

All eyes remain on the East as we head into the opening stanza of a La Nina Summer, but we’ll start next week with swell easing from the S/SSE as the trough system weakens and moves away. That should see some leftover 2-3ft surf at S facing beaches, dropping back during the day with light winds.

A couple of small days then look likely up into mid next week.

High pressure cells either side of New Zealand by next weekend (4-5/12) anchor trade flows in the South Pacific, intensified by the development of sub-tropical depressions along the northern flanks of the highs. Under current modelling a far system may generate a small E swell for late second week of Dec, while a more proximate system SW of New Caledonia has potential for the same period. 

The long lead time and lack of consistency in model runs lends low confidence to the medium term.

The arrival of the MJO in our longitudes suggests increased odds of tropical activity during this period.

Check back Wed and we’ll have a full update on it.