Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Monday 14th October)

Best Days: Tues: improving conditions with a solid south swell. Wed: smaller surf with light winds early. Thurs: solid renewal of S'ly swell with good winds in the morning. 

Recap: Saturday’s building NE windswell provided some fun late options about Sydney beaches, and the swell held a little longer than expected with Sunday morning producing fun clean surf of a similar size range, around 2-3ft. Also in the water throughout Sunday was a small southerly swell mentioned in last week's notes (and missed by the models), with occasional 2ft+ sets at south swell magnets. Today we’ve seen tiny clean conditions early ahead of a gusty S’ly change. A late increase in south swell is expected across the coast. 

This week (Nov 15th - 18th)

We’ve got two separate south swells on the way this week. 

Right now a Tasman low is driving a cold front across the Southern NSW coast, and strong to gale force S’ly winds in its wake will whip up large southerly swells for Tuesday. South facing beaches should see an early peak with set waves somewhere in the 5-6ft range, though the acute swell direction will create smaller waves at beaches with less southern exposure. 

Winds are looking a little dicey for most areas with fresh southerlies expected to persist overnight and into the early morning, however we should see an easing trend and a directional shift back to the SW before lunch across many areas (but possibly a late shift back to the S/SE, of light to moderate strength).

Some locations such as the Northern Beaches may see local topographical influences result in a pre-dawn through early morning W/SW flow though exposed northern ends will probably retain some surface lumpiness. 

Whilst this system will clear to the east on Tuesday, resulting in a steady easing trend in the size department, there are two feeder sources of swell that will supply good background swell through Wednesday. The first is a developing E/SE through SE then S’ly fetch at the bottom flank of the low - immediately west of the SW tip of New Zealand’s South Island today. 

Secondly, despite the Tasman low moving eastwards, a ridge will remain across the SE Tasman Sea on Tuesday with strong SW winds exiting eastern Bass Strait, which will continue to generate smaller sideband energy through the middle of the week in the 3ft+ range for south facing beaches. Early light W’ly winds on Wednesday will precede a moderate to fresh S’ly change through the afternoon.

A second cold front currently developing SW of Tasmania today is then expected to enter the Lower Tasman Sea later Tuesday, eventually merging with the remnants of the current Tasman Low by early Wednesday. This progression will result in gale force S’ly winds through the lower Tasman Sea that will kick up a renewal of solid south swell for very late Wednesday (Far South Coast) and Thursday elsewhere.

Whilst less favourably aligned for Southern NSW (partly due to the fetch orientation, and partly due to the more eastern position of the fetch), the groundswell generated should be very good quality - even if it only glances the coast. 

Surf size will probably be a little smaller on Thursday, generally 4-5ft at south facing beaches however the larger wavelengths associated with this swell (due to the stronger core wind speeds, and the slightly larger travel distance) should enhance wave heights at offshore bombies so 6ft+ sets are expected at some of these locations, and also across the norther Hunter region which usually draws in this kinds of south swells really well. Set waves will probably be more inconsistent than Tuesday's swell though, due to the poor fetch alignment.

Otherwise, once again expect smaller surf at beaches not completely open to the south. Conditions look great on Thursday with light offshore winds and NE afternoon sea breezes. 

Surf size will then abate rapidly into Friday, possibly some 2-3ft sets early morning at south facing beaches (mainly across the Hunter) but smaller elsewhere and easing throughout the day. Winds will freshen from the north as the day progresses and we may also see a small degree of NE windswell in the mix. But hopefully you’ll have had your fix well and truly by then!

This weekend (Nov 19th - 20th)

The weekend forecast is a little complex right now, as the models have been moving around a lot over the last few days.

Saturday will initially see a continuation of the northerly regime, though with very little windswell prospects. We’ll see some small residual south swell in the mix but I can’t see there being much more than slow, peaky 1-2ft waves at exposed beaches at best.

A trough is expected to move up the coast at some point over the weekend, either late Saturday or overnight into Sunday morning but the models are not resolving the process beyond that very well. However at this stage it looks like the most likely scenario will be a continuation of small swells across most beaches. I’ll update this over the coming days as more data comes to hand.

However, Sunday is also on target to see a very small but long period southerly groundswell, originating from a deep mid-latitude low tracking well below Tasmania later this week.

It’s not very well aligned for our coast but the sheer size and strength of the low (50kt+ surface winds) should override some of the directional deficiencies. As such south facing beaches could be looking at very inconsistent 3ft+ sets at times, with bigger sets across the northern Hunter region. Maybe even a few bigger waves. I’ll fine tune this in more detail on Wednesday.

Next week (Nov 21st onwards)

Nothing major standing out in the long term forecasts though the models have maintained a tropical system at the backend of the model runs within the Coral Sea since late last week, which seems to be slowly firming up as a swell generating system for Northern NSW. If this occurs, it could be a source of E/NE or NE swell for Southern NSW some time mid-late next week.