Sydney Hunter Illawarra Forecast by Steve Shearer (issued Mon May 13th)

Features of the Forecast (tl;dr)

• Fun waves Tues AM with good winds before swells ease
• Easing surf Wed becoming small Thurs with light winds
• S groundswell pulse Thurs PM/ holding  Fri
• Strong front and potential low sees sizey S swell and fresh S’ly winds this weekend- low confidence in specifics
• Plenty of S swell next week as fronts enter the Tasman

Recap

Plenty of robust swell over the weekend from sources in the Tasman and far southern ocean and ranging from E/SE to S- S/SE. Size was in the 3-5ft range across both days with bigger 6ft sets at S facing beaches and reefs,especially Sat. Conditions were complex as a coastal low formed in the trough line with light winds tending E/NE-NE on Sat and light winds tending SW-S on Sunday. Size is still in the 3-4ft range with the odd bigger set today with a morning W-SW flow set to tend S’ly and freshen through the day. 

Still plenty of swell energy this morning, clean before the S'ly got up

This week (May 13-17)

The low which formed off the NSW Central Coast yesterday is hovering almost due E of Sydney, generating a SW-S flow along the Eastern Seaboard as far north as the sub-tropics. The low is expected to drift off and dissipate as a new high moves in over NSW at a more northerly latitude compared to the recent pattern. Small swells from this low will ease through the week with some deep polar activity sending more small S swell wrap up the Pipe before a stronger frontal intrusion this weekend brings a sizier S swell with plenty of S wind.

In the short run we’ll see winds from the low continue to influence local conditions with a morning W/SW flow tending SW for most of the morning then S-SE after lunch (likely from mid-a’noon). Surf-wise as long period swell trains drop out of the mix we’ll see a mix of shorter period swells from winds feeding into, and exiting the southern flank of the low, primarily E/SE-SE with some short range S swell in the mix. Expect some 3ft sets through the morning but there will be an easing trend in play after lunch.

Winds should drop out and tend to morning offshores with a light/variable tending N’ly breeze in the a’noon on Wed as the low moves away and high pressure moves over Central NSW. Swell will be in the decline with some short range S to 2ft, dropping through the day.

Light winds for the rest of the week as high pressure drifts off the NSW Central Coast, likely tending to NE seabreezes Thurs with a slight question mark for Fri as a small trough moves in. It’ll likely stay W-NW tending NW-N but a weak S’fly flow could be on the cards. 

Tiny swells for Thurs AM as local swell sources dry up with some clean babyfood to a foot or so on tap. We should see some S’ly groundswell fill in during the a’noon to 3 occ. 4ft at S facing beaches generated by a broad fetch of gales passing under Tasmania Wed.

This source should hold 3 occ. 4ft sets for Fri with winds favourable for S magnets, as long as that sneaky S’ly doesn’t kick in. We’ll finesse winds Fri. 

This weekend (May18-19)

Another front Fri looks to track much more aggressively into the Tasman this weekend, with fresh S/SW-S winds likely Sat and a steep increase in S swell on the cards. Still some model divergence with GFS favouring a much more bullish outlook and size building up into the 6ft range with bigger 8ft sets on the Hunter and exposed reefs/bommies. EC would suggest a more bog standard S swell in the 4-5ft range at S facing beaches. S’ly winds are common to both models. 

Sunday depends on how this front evolves with GFS suggesting a low forming later Sat and moving offshore, with plenty of size from the S again (6-8ft at S facing beaches) and fresh S-SW winds easing as the low moves off. We’ll see how it looks Wed because models have consistently over-estimated potential low pressure development in the Taman Sea this autumn and size downgrades have been common. Under the more subdued EC prognosis we’d expect strong but easing S swell Sun with easing S’ly winds, possibly tending SW again as another front pushes into the Tasman. 

Next week (May 20 onwards)

We’ll see S swells of varying magnitude next week, likely persisting at least into the middle and possibly all of next working week as a series of fronts push into the Tasman.

As per the weekend f/cast there’ll still a lot of uncertainty surrounding the strength of these fronts and whether the weekend front forms a surface low over the weekend. 

We’ll peg in moderate/sizey S swells early next week with S quadrant winds and sharpen focus on Wed as we get more model clarity.

Seeya then.