Small surf all week; mixed options for the weekend

Ben Matson picture
Ben Matson (thermalben)

Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Monday 17th October)

Best Days: Sat: outside chance for a small easing NE swell with a brief window of good winds. Sun: chance for a solid S'ly swell.

Recap: Friday’s south swell eased steadily through the weekend, from 2-3ft sets across Sydney’s south facing beaches early Saturday down to a foot or so on throughout Sunday. We also saw a minor NE windswell develop during Sunday but it wasn’t very big and didn’t have much strength. A slightly bigger NE windswell built overnight and peaked this morning before easing this afternoon. There was a brief window of opportunity around the middle of the day as early N’ly winds swung W’ly and cleaned up conditions, where wave heights held in between 2ft and almost 3ft at NE facing beaches (see image from Manly, below), by it’s eased further since then.

Clean lunchtime peaks across the Manly stretch; for size reference, there's a bloke on the left

This week (Oct 18th - Oct 21st)

Today’s westerly change has no redeeming features of than its influence on surface conditions. 

It’s associated with a storm track that’s riding particular north in latitude, which means there is no secondary fetch to the south pushing into the lower Tasman Sea.

So, we have no significant south swell on the way in the near future.

The broader parent low still lies SW of Victoria, and is moving very slowly eastwards. It’s expected to pass across Tasmania on Tuesday afternoon, and will briefly freshen winds around to the NE across Southern NSW during the day (not enough to generate any new swell though). As such Tuesday will see small residual swell from today with early light winds ahead of the nor’easter.

A small SW fetch will then push up though the south-western Tasman Sea into Wednesday morning, generating a small south swell for the afternoon though no major size is expected. South facing beaches should see 1-2ft sets after lunch with bigger waves across the Hunter but it’s not really worth working around. 

Wednesday’s late new south swell should hold into Thursday morning, and may be reinforced by a secondary, slightly stronger south swell originating from the main fetch around the parent low south of Tasmania. Again, this fetch is poorly aligned and not particularly strong so I’d be surprised if we saw much more than very inconsistent 2ft sets across south facing beaches in Sydney (bigger across the Hunter) with tiny conditions elsewhere. Note: this size range is actually much higher than our surf forecast model is estimating - just one foot at south facing beaches - so keep your expectations low for Thursday's south swell potential.

Local conditions on Thursday look pretty average anyway with only a brief window of light variable winds at dawn ahead of freshening NE breezes through the day that could become quite gusty into the afternoon. A small NE windswell is possible late in the day though Friday morning is where we’ll most likely see any rideable action from this fetch, with 1-2ft surf early possibly increasing to 2-3ft late afternoon as the NE flow strengthens further ahead of an approaching southerly change for the weekend. South facing beaches will remain tiny though.

This weekend (Oct 22nd - Oct 23rd)

Friday’s strengthening NE flow has the most potential for the forecast period. And even then I’m only rating it a 50% chance of eventuating in decent surf.

Current expectations are that we’ll see short range NE swell peaking overnight Friday, before easing all day Saturday. Early Saturday sets should manage 2-3ft but it’ll become smaller during the day. Winds are expected to swing from the north to the west then the south, so it’s likely there’ll be a brief window of clean conditions for the open beaches around the middle of the day. Depending on the timing and strength of the southerly change, we may see a late increase in south swell too.

Let’s firm up the specifics on Wednesday.

Model guidance is then developing a broad, complex multi-centered Tasman low in the wake of Saturday’s southerly change that could very well deliver a sizeable, windy south swell for Sunday. Our surf forecast model has this pegged around the 6ft mark right now but let’s see how future model runs hold in before we get too excited. 

Next week (Oct 24th onwards)

Sunday’s Tasman low looks like it’ll remain a feature inside our swell window for a couple of days, meaning surf prospects should remain quite elevated through Monday and maybe Tuesday of next week. Otherwise, there are no other new swell sources of any interest for us.

See you back on Wednesday for a reevaluation of the Fr/Sat NE swell and Sunday’s solid S’ly swell.


Halfscousehalfcockneyfullaussie's picture
Halfscousehalfcockneyfullaussie's picture
Halfscousehalfc... Monday, 17 Oct 2016 at 7:09pm

I wouldn't mind some of these north east swells pumping up a bit to 3-4 ft in stead of the last couple of weeks 2-3 ft. there's some potential in a few sand banks around

thermalben's picture
thermalben's picture
thermalben Tuesday, 18 Oct 2016 at 8:06am

Wow, been a while since I've been caught out. This morning's small south swell (2ft sets south facing beaches) seems to have originated from one of my favourite, flukey swell windows - a W'ly thru' W/SW fetch exiting eastern Bass Strait yesterday.

However, wind speeds were only ~20kts and the fetch was almost completely westerly in direction - based on many recent swells from the same region, I figured these factored would result in a swell unlikely to make it ashore (we usually need at least a dominant W/SW alignment to allow the swell to spread back into the coast).

Unfortunately, ASCAT didn't provide a good data pass from the region yesterday so I was unable to confirm whether winds were higher than modeled.

Even with the benefit of hindcasting, these charts certainly don't raise any flags for me - looks like the fetch was just enough over the threshold to kick things into gear. Another one for the knowledge bank!

dannyz's picture
dannyz's picture
dannyz Tuesday, 18 Oct 2016 at 8:18am

a nice surprise nonetheless! So is Weds morning now looking any better than originally forecast Ben?

thermalben's picture
thermalben's picture
thermalben Tuesday, 18 Oct 2016 at 8:45am

Nah, it's a seperate, new swell - it has no relation to today's pulse. Each swell is assesed independently.

That being said, I'll recheck the deets for tomorrow's swell this afternoon.

alexsmith1's picture
alexsmith1's picture
alexsmith1 Tuesday, 18 Oct 2016 at 9:39am

Definitely flew under the radar.. not many bods in the water this AM. Hopefully it hangs around this afternoon

thermalben's picture
thermalben's picture
thermalben Tuesday, 18 Oct 2016 at 4:13pm

Small south swell in Newy this arvo, notice how close the lines are together - shows its short range/low period energy.

No change to the forecast for tomorrow either, small S'ly pulse in the arvo.

ojackojacko's picture
ojackojacko's picture
ojackojacko Tuesday, 18 Oct 2016 at 7:25pm

thanks ben. appreciated