Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 30th Aug)

Features of the Forecast (tl;dr)

• Continuing small mixed bag Thurs (low point in energy) with light winds AM, tending S’ly then W’ly late
• Low pressure trough likely to form in Tasman Fri with increasing S’ly winds and swell
• Mod S swell likely Sat with SW-S winds
• S/SE swell on the small side Sun with offshore winds
• Small E/NE swell in the mix Sat/Sun
• Small S/SE swell Mon, with winds tending N’ly
• SE pulse Tues, persisting Wed, with N’ly winds Tues and a S’ly change Wed
• More S swell in the medium term

Recap

Long period S swell slowly tailed off yesterday with some inconsistent 3-4ft sets at S facing beaches in the morning under morning offshore winds the best of it. A’noon NE winds added a bit of NE windswell to the mix. Clean conditions again this morning under a light W-NW flow, expected to tend to N’ly breezes. A small mixed bag on offer with some leftover S swell and E-NE swell offering up some mostly 2ft surf with the  occ. 3ft set.

Red sky at morning with a small mixed bag

This week (Aug 30- Sep 1)

There’s a troughy pattern in play at present, with a long trough snaking from inland QLD down to the Central/Southern NSW Coast. Return flow off the back of a retreating high is feeding N’ly winds into the trough line. We’re expecting a front to interact with the trough overnight Thurs to form a low pressure trough in the Tasman. This trough then absorbs another trough of low pressure moving south from the South Pacific islands to form a large area of low pressure near New Zealand. Compared to Mondays notes the components of this complex pattern all look a little weaker and more mobile with reduced swell generating potential, but we will still see some useful pulses from the various incarnations of the broad pattern.

In the short run and we’ll see a low point in swell tomorrow with just minor levels of E swell filtering down from the sub-tropics and remnants of S swell - topping out around 1-2ft at most open beaches. Conditions should be clean early under a W/SW-SW flow as the trough/front approaches but latest model runs show winds shifting SW-S fairly rapidly in the morning and freshening. We may see a late kick back to the W as another arm of the trough exits the coast around the Sydney region. It’ll be a tricky and late change if it happens.

We’re still on track for a reasonable spike in S swell through Fri, although most of it will be short range energy whipped up by the proximate fetch to the Southern NSW coastline, and accompanied by fresh S’ly winds. An early window of SW winds will be on offer, but without much swell to work with, just a foot or two at open beaches. Winds kick up from the S and it won’t be until after lunch until dark that we really see the swell pick up. To get out of the wind and sea state you’ll have to sacrifice a lot of size so keep expectations pegged pretty low for Fri.

This weekend (Sep 2-3)

The proximate fetch moves away quickly by Sat, leaving a mod SW flow early, tending S’ly during the day. That will see a moderate amount of mid period S swell in the water, fairly uninspiring to be honest, with size in the 3-4ft range at S facing beaches, bigger by a notch on the Hunter. S winds will force you to more protected spots for a clean wave and there will be some small E/NE swell getting in there from a southwards moving fetch from the South Pacific slot. That should supply some clean 2ft surf with the occ. 3ft set.

Winds drop right out for Sun as another troughy area moves across the state, with light morning offshores and weak a’noon seabreezes likely. The low pressure trough briefly exhibits a SSE fetch in the central Tasman and this should be enough to supply some 2-3ft surf through Sun, mixed with a small signal of E/NE swell to 2ft+. With the more favourable winds and small combo swell there should be some fun peaks around on the beachies. 

Next week (Sep 4 onwards)

Successive model runs have downgraded the potential fetch out of Cook Strait later this weekend, so we’re looking at a small S/SE swell signal for Mon with light winds and NE breezes.

SE-E/SE swell from Cook Strait then arrives Tues and lingers into Wed but size is more likely to top out around 3ft, although we’ll still have Fri to finesse size and timing. N’ly winds look likely for Tues, with a troughy, shallow S’ly change for Wed. 

Small bits and pieces then pad out the rest of the week, mostly remants of SE swell.

Longer term and there is frontal activity passing into the Tasman later next week which suggests some small S swell potential for Sep 9/10.
GFS continues to hint at instability in the Coral Sea or near South Pacific but considering the recent history of downgraded forecasts we’ll keep froth very much contained and see how it looks on Fri. 

Seeya then.