Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 28thDec)

Forecast Summary (tl;dr)

• Slow increase in E/NE swell Wed PM persists into Thurs with flukey SW-S winds Thurs AM, tending SE-NE in the a’noon
• Workable fun E/NE swell Fri with E-NE winds re-establishing
• Fun E/NE swell continues NYE, with a muscling up in size New Years Day and light/mod NE winds 
• Much stronger E swell fills in Mon with NE winds
• Strong E swell holds Tues, slowly easing Wed/Thurs with S’ly winds becoming established
• Slow easing in E swell into next weekend
• Still monitoring the tropics as Monsoon trough remains active

Recap

The N’ly pattern set up as expected with mostly tiny surf through yesterday. A surprise packet did arrive as extra long period S swell from a bombing low which traversed the Southern Ocean below Aus Xmas Day made landfall. That saw some inconsistent 2-3ft surf show at S facing beaches. That signal has continued into this morning, albeit becoming very slow, and with a slow rising E/NE swell overlaid across it.

A few small S swell lines with E/NE swell starting to build in over the top of it 

This week (Dec 28-30)

The building blocks for a classic Summer monsoonal pattern are now firmly in place and almost the entire Eastern Seaboard from the Tropic of Capricorn to Tasmania is going receive swell as a result of it.  A dual-centred high straddles New Zealand with an elongated monsoonal low pressure trough located in the Coral Sea and extending into the near South Pacific. This is creating a long and broad E’ly fetch which is slowly extending southwards. As we near the end of the week, a more discrete surface low hives off the end of the monsoonal low pressure trough and retrogrades back into the Tasman Sea as it intensifies, generating large E’ly swells over the last days of 2022 and first days of 2023.

In the short run and the initial stages of the fetch have created a tradewind type swell for the subtropics and this swell will slowly filter down to temperate NSW through tomorrow. Expect a playful 2ft of E/NE swell to be in the water through tomorrow. Winds look a bit tricky though as a trough moves through the region before stalling out and dissipating on the lower Hunter. Thats likely to see a morning light and variable flow from Sydney north with the Syd-Illawarra region seeing more mod S’ly biased winds. Through the a’noon, as the trough dissipates and moves offshore we’ll see a light SE-NE flow develop. 

Light winds should hold into Fri morning with some fun beachies perking up into the 2-3ft range before an E/NE flow starts to kick in. By close of play we should see size more locked into the 3ft range. 

Nothing major but there should be enough fun beachies around to roll the arms over in preparation for the juicier days to come. 

This weekend (Dec 31-Jan1)

Compared to Mondays notes we’ll still be in a slightly under-sized phase of this swell event through NYE. Thats due to the low pressure trough remaining primarily in the Coral Sea and the E’ly fetch aimed more directly at sub-tropical targets. 

Still, we’ll see workable levels of E/NE swell in the 3ft range through Sat with light/mod NE winds affecting surface quality but still maintaining reasonable conditions if you aren’t too fussy.

The first, stronger pulse is now due in Sun- New Years Day. We should see a more notable increase in size and juice with sets building into the 4ft+ range through mid-morning. 

A generous attitude to wave quality may be required as as that light/mod N to NE flow continues but there is good odds for lighter NW-N winds inshore early. The increase in wave size and favourable direction should compensate for the light onshore flow.

Next week (Jan2 onwards)

If models hold true we’ll be looking at the main course of this swell event to kick off 2023. Over the weekend a low hives off from the end of the large area of monsoonal low pressure and begins to drift SW back into the Northern Tasman (see below), intensifying with E’ly gales aimed back at the Eastern Seaboard. With the fetch travelling in the same direction as the propagated swell trains, we’ll see enhanced potential for swell production.

Expect a solid muscling up in size through Mon, with initial 4-5ft surf building into the 6ft range through the day as size and period increase. Outliers amongst some of the South Coast reefs are likely to see bigger 6-8ft surf by close of play. You’ll have to deal with increased NE wind though as a trough approaches from the W. 

Size holds at a solid 6ft (bigger at exposed reefs) into Tues morning . A trough brings another tricky wind outlook, with early variable winds, tending S/SE and then light E’ly during the day. Thats not set in stone, so check back in Fri for an update. 

Flukey winds carry-over into Wed AM as the trough hovers about the coast before a more settled S/SE flow kicks in as a new, major high pressure ridge moves in from the Bight. 

Plenty of size is expected to hold into Wed as the low slowly hovers in the Tasman. Expect 4-5ft surf Wed, slowly easing into Thurs.

Under current modelling we’ll see winds tend S-SSE in a more stable synoptic flow. 

The easing trend is expected to continue into next weekend.

Longer term and we may see some S quadrant swell next weekend from S’ly winds in the Tasman, associated with a front pushing through. The monsoon trough still remains active and although models have gone a bit cool on cyclogenesis in the Coral Sea we may till see further low pressure development in that area or possibly further south associated with the remnants of this weeks low pressure.

Get your paddling arms ready and be ready to drop your standards a notch to deal with some onshore winds.

Check back Fri for the latest.