Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 31st Aug)

Forecast Summary (tl;dr)

• Slight S swell increase Wed PM, extending into Thurs AM with improving winds
• Minor E'ly swell Fri into weekend
• Vigorous S’ly flow kicks in Fri as low forms off MNC
• Late kick in local S swell Fri, extending into Sat and Sun with plenty of size
• Long period S swell with plenty of size expected Mon PM, peaking Tues, easing Wed with light winds tending N’ly
• NE windswell possible later next week
• Looking to the S by next weekend for more swell as fronts push through, stay tuned for updates

Recap

Small bits and pieces through yesterday, with a bit of NE windswell not exceeding 2ft and continuing marginal surf into today. Early NW winds are tending S’ly as a weak, troughy change works it’s way north. Odds are now firming  for a much more dynamic period from Friday. Details below.

Small, weak swells in the drizzle. Much more action coming

This week (Aug 31-Sep 2)

No significant changes to the outlook. The current pattern- with weak high pressure drifting across Central NSW and a soft ridge along the coast- will be replaced in emphatic fashion by a much stronger front and trough on Friday, anchored by a monster high moving into the Bight at the same time. Well to the south of that set-up will be a deep polar low and associated fronts with severe gales to storm force winds generating long period S’ly swells to make landfall early next week.

In the short run the current S’ly change quickly runs out of steam tomorrow with the soft ridge seeing weak E-NE breezes establish in the a’noon. Not much surf is expected, just a small signal of S swell in the 1-2ft range, 2ft+ on the Hunter and easing through the day. A few small E’ly swell trains generated by a distant tradewind fetch will supply some marginal background surf from that direction with size less than 2ft. 

Friday looks dynamic. A trough off the coast is activated by a strong front, with an early convergence zone around the Hunter likely to see NW winds. S’lies should embrace the rest of the region early morning. By lunch-time S’lies will really freshen as the trough moves offshore and deepens. A late kick in new, local S swell into the 3-4ft range will be limited by winds, with only small surf at sheltered locations. Minor E swell will supply small energy into these spots if you are happy to work around fresh S’lies.

This weekend (Sep3-4)

The trough deepens north of Lord Howe Island overnight Fri and into Sat (see below) with a surface low forming N of the Island. That will concentrate gales in the sub-tropics, with the biggest surf generated well north of temperate NSW. 

We’re still looking at some size for the region over the weekend, especially Sat, although fresh/strong S to SSE winds will limit surfable options. Expect size in the 5-6ft range at S exposed breaks, with much smaller surf in sheltered corners, where a small amount of background E swell will help the cause. 

That size holds into Sun morning, although there is still some model divergence on the position of the low, with EC holding the low further north, compared to GFS. We’ll finesse size on Fri but for now pencil in 6ft of S/SSE swell with fresh S’lies, slowly moderating through the day. 

Next week (Sep 5 onwards)

Leftover S’ly flow will still be with us on Mon, albeit at reduced speeds and likely to tend to a morning SW land breeze north of the Harbour. Through the morning , mod S’lies will kick in and they will blow out S facing beaches, which will still have 4-5ft of swell. Through the a’noon, we’ll see long period swell trains from the vast polar storm passing between Australia and New Zealand Fri-Sun. That will see 4-6ft sets at S exposed breaks with smaller surf at more sheltered breaks.

Long period swell is expected to peak Tues with solid sets to 6ft, bigger 8ft at exposed S facing reefs. Unfortunately, local winds are now looking a bit shabby as the S’ly flow remains persistent. Odds are good for a morning SW wind across the region before a light SSE to SE breeze kicks in. There may be some pockets of lighter wind south of Jervis Bay but you’ll have to keep eyes on local weather obs and be ready to react. 

By mid next week we’ll be seeing easing swells from the South, although still plenty of juice available Wed, with expected size in the 4-6ft range, easing during the day. A high moving East of Tasmania should see a light offshore morning wind, with light N’lies in the a’noon. 

N’lies increase to end next week, with good odds for some workable NE windswell to end next week. With another strong frontal progression looking likely to generate another round of S swell. Confidence is low this far out so lets see how it’s shaping up Fri.

More on that in Fridays f/cast. See you then.