Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 19th Oct)

Forecast Summary (tl;dr)

• Small S swell pulses this week Tues/Wed, slightly stronger Fri- only showing at S swell magnets
• NE windswell now building late Thurs, becoming chunky Fri and extending through the weekend and into early next week
• N’ly winds Sat with a S’ly change now likely Sun AM
• NE winds re-establish Mon 
• Small SSE-SE swell likely from late Mon into Wed as trough moves off South Coast
• Stronger, mid period E/NE swell building Mon peaking Tues, easing off Wed, 
• Winds possibly tending offshore Wed, stay tuned for updates
• Complex, troughy pattern remains so expect constant revisions!

Recap

A slight bump in E swell yesterday held wave heights at around the 2-3ft mark, with early light winds tending to an onshore E to ENE’ly flow. Nothing amazing but surfable. Today has seen surf ease a little into the 2ft range, with the odd bigger one more prevalent on the Hunter. Clean conditions early before a weak trough brings a fairly feeble S’ly change which will tend SE/NE through the a’noon.

Still some small clean options this morning before the S'ly change

This week (Oct 19-21)

We are in between patterns at present with a feeble trough delaying the start of the next pattern. That will see an approaching inland low and high pressure system generate increasing NE winds across most of the Eastern Seaboard. The onshore flow is enhanced into a deeper tradewind flow up in the Coral Sea, which gets a boost from a trough of low pressure expected to form off the Central QLD Coast this weekend. All of which is to say the dominant swell trains will be from the NE to E/NE through the short to medium term.

In the short run and we’ll see a low point in wave heights through Thursday, with small leftovers in the 2ft range through the morning. Through the a’noon we’ll see the NE flow start to kick, spelling an extended period with winds from this direction. Expect a small increase in size- just short period NE windswell up to 2ft+.

A bigger increase in NE windswell is still on the cards for Fri as both local NE winds and a proximate fetch to the NSW coastline increase in speed and extent. Expect winds to exceed 20 knots through the day and NE windswell to build into the 3-4ft range, likely a notch bigger (4-5ft) on the Hunter and South Coast. As mentioned on Mon, the last of a series of fronts rapidly transiting the Tasman this week is likely to supply some 2-3ft S swell Fri, mostly swallowed up by the NE windswell apart from reliable S facing swell magnets.

This weekend (Oct 22-23)

Saturday still looks unchanged with a mod/fresh NE flow that looks to contract a little towards NNE to N during the day, as the inland trough of low pressure approaches the coast. Plenty of NE swell is expected with size in the 4ft range, along with easing S swell which will see some morning sets to 2-3ft at S facing beaches, easing during the day.

Sunday now looks much trickier, at least wind-wise. The approaching trough generates a shear trough line Sun morning which approaches the region in the early hours. There’ll be a window of light NW winds in advance of the trough line and S’lies behind it. Under current modelling it looks to arrive close to dawn in the Illawarra and propagate north to be in Sydney early morning. The Hunter should have a more leisurely window of NW winds before the change. Expect NE swell down a notch as the approaching trough shunts the fetch eastwards, with size to 3-4ft early, easing during the day. Some small, short-range S swell is possible later in the a’noon but unlikely to be worth working around.

Next week (Oct 24 onwards)

Plenty of action on next week’s synoptic chart (see below). High pressure sits well south of Tasmania and anchors a fetch of SE-ESE winds, which is better aimed at Tasmania and the Gippsland Coast but will supply some small SE swell for the f/cast region likely from Mon, into the 2-3ft range and extending into Tues at least at similar sizes.

That swell will be overshadowed though by a more dominant NE-E/NE swell as a trough of low pressure off the QLD Coast drifts south and drags a tradewind-style fetch south with it. This will be a chunkier, longer period swell than the previous NE windswell so expect a bit more juice to it.

This should see surf build into the 3ft range Mon, with winds clocking back around to the NE-E/NE.

Stronger E/NE swell then fills in Tues into the 4-5ft range with NE winds remaining intact. 

We may see a wind change Wed as the next approaching cut-off low drifts towards Victoria/Southern NSW, possibly exiting around the Gippsland Coast. If this happens we will see an offshore W’ly flow develop, with a mix of mid period E/NE swell and more local NE swell.

Pencil in Wed for now, and we’ll see how this wind shift is shaping up on Fri.

Troughy bits and pieces everywhere on the charts for late next week, which means confidence this far out is extremely low. Odds are we will see easing swells into the end of next week, with winds dependent on the movement and position of the various trough lines.

Check back Fri and we’ll have a better view of next week, as well as a final tune-up for the weekend. See you then.