Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed Sep 11th)

Features of the Forecast (tl;dr)

• Spike in new S swell Thurs as trough of low pressure forms offshore , windy from the S/SW-S/SE
• Still sizey but easing S swells Fri with S’ly winds easing during the day
• Light winds Sat small swells
• Strong S swells Sun strong S’ly winds easing and tending S/SE in the a’noon
• Mix of S swells likely early next week- potentially some good long period S'ly groundswell Tues/Wed with mostly offshore winds and a’noon seabreezes
• Small surf from mid next week
• Potentially more S swell medium term, possibly sizey

Recap

A small pulse offered S-S/SE swells in the 2ft range yesterday with the occ. 3 footer at S magnets. Conditions were workable under light winds before NE breezes kicked in. Size has eased back a notch today with the occ. 2 footer under W/NW winds expe4cted to tend N’ly and freshen through the day.

The odd fun peak on offer this morning

This week (Sep 11-13)

We’ve got high pressure moving across the Tasman with a much stronger dual-centred high tracking into the Bight. A trough between them moves offshore tomorrow forming a fast moving trough of low pressure in the Tasman, which tracks rapidly NE. We’ll see a spike of S swell from this system, downgraded from Mon. A following front and trough now looks stronger, earning an upgrade. More S swell into the middle of next week from polar activity tracking NE with good winds expected. Let’s dig in.

We’ll still see fresh S’ly winds develop tomorrow as the trough moves offshore and deepens. Early W’ly breezes should be confined to the Hunter and Central Coast with the S’ly flow in by dawn across Sydney and freshening rapidly by office hours. There may be some minor NE windswell on offer for the diehards but we’ll see short period S’ly swells building in through the a’noon to a raw 3-4ft, with bigger 4-5ft surf across true S facing stretches like the Hunter. Much smaller in sheltered locations due to the steep swell angle and low swell periods.

We’ll see the S’ly flow in Fri morning with mod S’lies (more SW across the Northern Beaches) so expect it to be pretty raw and ragged. Size in the 4ft range (bigger 5ft on the Hunter) and that will ease quite quickly through the a’noon as the fetch moves quickly to the NE. Local winds will ease off quickly too as pressure gradient slacken with SE-E breezes dropping to less than 10kts by close of play.

This weekend (Sep14-15)

We’ve got greater confidence on the weekend outlook as models come into alignment over the strength of the follow-up front expected on the weekend. Sat looks calm with a slack pressure gradient offering light winds all day, early offshores and light seabreezes. Not much size, just some small leftover S/SE swell to 2 occ. 3ft early, easing to 2ft or less through the day. Definitely worth a look though with good conditions.

The front now looks to push through Sydney around dark or just after bringing fresh/gusty S’lies that will blow strongly o/night Sat into Sun, tending SW-S/SW in the morning. This fetch is broader, stronger and extends further into the Tasman the Thursdays rapid fire fetch so we should see surf of a bulkier dimension into Sun up into the 5-6ft range with bigger sets and solid 6-8ft on the Hunter. Very windy though with S exposed breaks blown to shreds. There’ll be smaller, workable options at protected spots under fresh S’lies. The fetch does move away during the a’noon with local winds also moderating and tending S/SE from mid a’noon.

Next week (Sep16 onwards)

Easing swells on Mon, from a high base with size to 4-6ft early dropping through the day. Winds look good as high pressure moves into the bight and a troughy area sits over coastal NSW and a new front pushes into the Tasman. Light morning land breezes should tend to weak seabreezes making for good conditions most of the day.

We’ll see another complex of S swell trains make landfall on Tues. Mostly mid period S from the frontal intrusion into the Tasman (see below) but there will be come much longer period swells in there from polar sources. 

Tues and Wed are looking good with mostly offshore winds and light N’ly breezes favouring S facing beaches.

At this stage, under current modelling we should see size to 4-5ft at S facing beaches Tues , holding into Wed before easing during the day. We’ll finesse size and timing on Fri but at this stage it looks pretty good.

The rest of next week now looks quite small. There’s still some suggestion of a N’ly infeed into a trough from EC but it looks ,much weaker than on Mon. 

Small surf looks likely for the second half of next week.

A strong front and low approach the Tasman late next week or weekend and certainly offers the chance of a major S swell. Long way off and confidence is low so check in Fri and we’ll how it’s shaping up.

Seeya then.