Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Nov 15 )

Forecast Summary (tl;dr)

• Small bump in S swell Mon PM from Bass Strait fetch
• Slightly undersized S swell Tues AM before stronger S swell fills in. Best winds AM
• Longer period S swell Wed, with winds becoming light
• Easing S swells Thurs with freshening NE winds
• Small NE windswell Fri
• Small mix of swells Sat with freshening NE winds
• Small bump in S swell Sun
• Uncertain outlook for next week, check back Wed

Recap

S swell pulses have been on the menu this weekend, a little light on and on the “cool”end of the forecast range. Saturday saw W’ly winds most of the day with small 2ft S swell, bigger 2-3ft on the Hunter. Size perked up yesterday with a fresh pulse which maxed out on the Hunter with 4-5ft surf, 3-4ft at S facing beaches in the Sydney basin and elsewhere, and swell ramped downwards through the a’noon, with a mostly offshore flow all day. 

That pulse has now faded right back and this morning saw tiny surf across the region, brushed by continuing W’ly winds. Short term prognosis is good though, with a strong cold front now pushing into the Tasman and S swell ahead, building slightly this a'noon from a Bass Strait fetch. Read on for details.

This week (Nov 15-19)

A deep mid-latitude low with high pressure support in the Bight and multiple cold fronts has now moved E of Tasmania with W to SW gales pushing out of Bass Strait and a deeper SSW fetch pushing up from the Southern Ocean into the Tasman Sea. It’s a wintry looking system and it has a nice sting in the tail as a small troughy intensification slingshots up into the Tasman Sea through tomorrow, giving another longer period pulse S swell to add onto the main body of the swell.

Surf from this system shows tomorrow, primarily the Bass Strait refracted S swell, which will have filled in late this evening/overnight. That will supply surf a bit undersized but in the 2-3ft range through the morning at S facing beaches, bigger 3-4ft on the Hunter. Cleanish under early W/SW winds, which will be fresh at times. Size builds into the a’noon, up into the 3-4ft range at S facing beaches, bigger 4-5ft on the Hunter. Winds will be a problem as they tend S/SE as a high pressure ridge builds in quickly behind the passage of the front. Size sacrifice will be required to find cleaner conditions with protection from the wind.

The lingering S’ly flow extends into Wed morning, likely SW inshore across the Sydney basin through the early morning. Winds should lay down in strength quickly as high pressure moves over the area, leading to weak breezes then light E/NE winds through the a’noon. There’ll be plenty of swell in the water. The initial body of S swell will be supplanted by longer period S swell from the troughy slingshot Mon. Those swell trains will overlap, with the stronger swell expected to fill in from lunch-time. Size in the 3-5ft range, bigger 4-6ft on the Hunter is expected through the day, so if you can work around the not quite ideal  winds there should be a few options available, especially if you can sacrifice a bit of quality for size.

Thursday sees the downslope of the swell with early size in the 3-4ft range at S facing beaches, easing back during the day. The N’ly pattern kicks in during Thursday, with lightest winds early, possibly NW before they tend NE and freshen. With best conditions and most size in the morning it makes the early a no-brainer.

N’ly winds blow overnight Thursday, with a proximate fetch to the Central NSW coast expected to generate a peak in NE windswell through the early morning in the 2-3ft range. These fetches tend to exhibit high variability in model to model runs, so we may need a fresh look Wed. At any rate, conditions Fri will be determined by a troughy S to SE change during the day. We’ll finesse that call on Wed.

This weekend (Nov 20-21)

Tricky little weekend ahead with no major swell sources but enough flukey swell trains to get wet.

Sat looks the smallest of the two days. Friday’s weak troughy change quickly slides off into the Tasman, with a transient fetch of SE/ESE winds likely leaving some weak 2ft surf in it’s wake from that direction. A new high pressure ridge sets in, leading to winds freshening from the NE during the day. That should see a bit of NE/ENE windswell in the 2ft range. If you can get your head around small, weak windswell there should be enough for a grovel on Sat.

Sunday has slightly more potential. A front passing through the lower Tasman Fri/Sat is expected to generate a broad swathe of seas in the 15-20ft range. While most of that is aimed at New Zealand targets, radial spread from the source is expected to see some mid period S swell on Sun. Size in the 2-3ft range at S facing beaches is on the cards, possibly 3ft on the Hunter. N’ly winds freshen as an inland low approaches, then tend NW and possibly W as the low approaches the coast. Possibility exists for small NE windswell on Sun, as well. Depending on the timing of the wind change, a window opens for some clean, small surf on Sun but keep expectations low.

Next week (Nov22) and beyond

The interior low exits the coast Mon next week, driving W’ly winds across the region. Surf potential from this low as it enters the Tasman looks constrained from this far out. Without a supporting high pressure ridge the low dips south with winds aimed at Tasmania, then meanders across the Tasman, with quite a weak fetch through Bass Strait, then along the western flank of the low.

Thus we’re only looking at a modest S swell potential from the low, probably bumping a notch during Tues next week, into the 2-3ft range at exposed S facing beaches. Mon is likely tiny.

Another interior cut-off low is expected to approach the coast Wed, suggesting an increased NE infeed into the low and potential for NE windswell by during Wed next week.

This unstable pattern is likely to have low model predictability so expect major revisions as we enter next week. Get what you can from this round of S swell because the following period looks small and flukey.

Check back Wed for a full update.