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

Features of the Forecast (tl;dr)

• First pulse of longer period S swell Tues with N’ly winds tending variable
• Stronger long period S swell Wed with early light winds, tending variable then S-SE
• Easing S swells Thurs with early SW winds tending S’ly
• Mod short range S swells Fri with fresh S’lies easing during the day
• Mixed bag Sat with small S swells and some possible E/NE swell from Pacific depression or TC
• Another strong, long period S’ly groundswell pulse Sun with tricky winds
• Troughy, unstable outlook into next week, stay tuned for updates

Recap

NE windswell over the weekend supplied plenty of fun moments with Sat up in the 3ft range under a fresh N/NE flow. Sun morning was a similar size with a S’ly change arriving in the early morning and confining clean conditions to protected spots. A little kick in size and late afternoon glass-off was a treat for the keen through Sun a’noon. Tricky, troughy winds this week with some juice from the S. Details below.

Fun NE windswell over the weekend- Sun morning after the S'ly

This week (Nov 13-17)

Quite an active synoptic situation to start the week. The continent is unstable with a heat trough over NWWA and more troughs extending from the interior  through to the East Coast. A deep low and powerful frontal system with a long trailing fetch is currently traversing the lower Tasman, generating long period S swells. In the tropical South Pacific an area of convection is currently organising and deepening into a tropical depression and potential TC east of the Solomon Islands. This depression or TC is expected to race through the swell window and send a small pulse of swell our way. 

In the short run yesterday’s S’ly change quickly washes out under a weak synoptic environment with winds tending N’ly tomorrow as a small high sits off the Central NSW Coast and a trough approaches. A small pulse of long period S swell is en route, likely filling in mid-morning with some 3ft sets at S facing beaches, small elsewhere. Some magnets may hoover up extra size. 

Stronger S swell with uncommonly long swell periods then fills in o/night Tue into Wed. No real change to that outlook. With swell periods in the 16-17 second band we can expect some juice and outliers from swell focussing at S facing reefs. We’d mostly expect 5-6ft surf at S exposed breaks, with bigger 6-8 and even a few 8-10ft sets possible at those direct S facing swell magnet reefs. Winds will be tricky as a trough hovers off Jervis Bay. We should see a light/variable flow with a N’ly bias Hunter-Illawarra for the early to late morning before S’ly winds after lunch. A light E’ly flow then looks likely for the late. It’ll be tricky so keep tabs on your local wind obs. 

Light winds into Thurs morning, likely SW early before a mod S’ly flow as a weak front pushes up the coast. Size will have eased from Wed’s long period pulse with some 5-6ft sets at S facing beaches early, easing during the day. 

The front combines with a trough and paired systems create a large S’ly wind field in the Central-Northern Tasman on Fri. That will see mod/fresh S’ly winds tending lighter SE and a moderate short range S swell. Not much in the way of quality but we should see 3-4ft of S swell, bigger on the Hunter, back down a notch in the a’noon. With easing winds there’ll be some sloppy but surfable options to wash off the working week.

This weekend (Nov 18-19)

We should see light winds tending N’ly on Sat as a small high centre moves offshore from the Central NSW Coast. An off-axis fetch in the Tasman and the remnants of Fridays short range S swell should hold a small blend of S swells to 2-3ft at S facing beaches, likely biggest and best early before an easing trend sets in. In addition the tropical depression or TC (Mal) which is expected to track SE through the swell window Wed/Thurs is expected to send some small E/NE swell our way. It’s a tricky, compact free-standing system but we can reasonably expect some 2 occ. 3ft sets Sat into Sun with revision to come this week.

Sunday is a different story. Another powerful low tracking into the Far Southern Tasman- this time at potential storm force- sends more uncommonly long period S swell up the NSW Coast (although better aimed up the Tasman Sea pipe towards Fiji). With swell periods potentially  in the 19-20 second band there’ll be some real juice in the swell. Typically we see a large range of wave heights with these events due to bathymetry effects and subsequent swell focussing, even at S facing beaches. We may see some solid 6-8ft sets at S facing reefs Sun (possible 8-10ft at some deepwater reefs), with smaller surf elsewhere, although all S facing exposures should see solid sets fill in mid-late morning with biggest sets in the a’noon session. Winds look tricky again, with high pressure  off the NSW Central Coast feeding into a trough. EC has a more favourable (for S facing reefs) N-NE flow while GFS has a more direct onshore E/NE flow expected. Stay tuned for wind updates through the week.

Next week (Nov 20 onwards)

We may see a small trough of low pressure form off the NSW South Coast next week, with an initial infeed of NE winds suggesting NE windswell later Sun into Mon. Along with easing S’ly groundswell from Sun.

Potential is there for SE swell if the trough of low pressure winds up early next week, but model agreement is poor and with so much troughiness and instability expected, low confidence in outcomes this far out is warranted.

Check back Wed and we’ll see how it’s shaping up.