Great waves Thursday; small funky S and SE swells beyond

Ben Matson picture
Ben Matson (thermalben)

Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 26th August)

Best Days: Thurs: excellent combo of easing E/SE and new S'ly groundswell, with offshore winds. Fri: smaller but clean early. Sat: Initially punchy but easing S'ly swell with offshore winds. Mon/Tues/Wed: should be a combo of SE and S'ly swells in the water.

Recap: Considering the tricky nature of the ECL, I'm reasonably pleased with the overall outcome of the last few days. Wave heights remained static for most of Tuesday, before surging overnight and then slowly easing throughout today. Tuesday's winds were excellent, whilst a shallow S'ly tending SE breeze bumped up the Sydney and Illawarra region this morning, before winds returned to the SW this afternoon. 

This week (Aug 27 - 28)

We've got some great waves expected on Thursday. Today's E/SE swell will continue to ease in size (3-4ft early, smaller later), and it'll mix in with a long period southerly swell pushing up the coast that should offer 4ft sets at south facing beaches. Locations south of Sydney should see more size from the E/SE as the fetch is aimed in better there, set waves could still be somwehere between 4ft and maybe 6ft early morning. 

Crucially, winds will veer westerly as the ECL dissipates in the central Tasman Sea. So, all open beaches should be nice and clean, and locations open to the south should see some rather solid peaks at times as the two swell trains interact.

On Friday, the general trend will be downwards as both the E/SE and S'ly swells ease back in size (~2ft+ or so open beaches, mainly south facing). Conditions should be good early with freshening W'ly tending W/SW winds however a new low is expected to form off the Far South Coast in the early hours of the morning, and it'll push along the Southern NSW coast during the day, bringing a gusty S/SW wind change to the South Coast mid-late morning, Illawarra around lunchtime and the Sydney region early afternoon (Hunter coast mid-late afternoon). 

This should kick up a very late increase in short range S'ly windswell at south facing beaches (maybe some 3-4ft sets right on dark if we're lucky) but these locations will be bumpy under the accompanying winds and it'll be much smaller elsewhere. So, aim for smaller cleaner waves early in the morning.

This weekend (Aug 29 - 30)

The weekend's forecast remains very tricky. Friday's late south swell is expected to be a short lived event and will peak overnight. I don't think we'll see a great deal of size early Saturday morning but a few stray 3ft+ sets at dawn are possible at south facing beaches (bigger in the Hunter, smaller elsewhere). However by mid-morning it'll be easing and the downwards trend will continue throughout the day, with very small surf expected late afternoon.

A new low pressure system developing well south of the Tasman Sea (technically the Southern Ocean) on Friday looks like being a tricky bugger to forecast for too. An initial S/SE fetch is now modelled to retrograde NW back up into the Tasmanian region, but it may briefly push up inside our acute south swell window. It's a very unusual pattern, and this exaggerates the difficulty in estimating surf size because I can't recall seeing a fetch track in this direction, in this region before. So there's no precedence to work against.

Additionally, the models have been moving around a lot with this synoptic setup in recent runs (shunting the fetch inside, and then outside of the swell window). It's quite likely that they'll continue to move around for the next few days so let's leave the outlook for Sunday until things firm up, hopefully by Friday.

However, aside from this south swell as a possible source for Sunday, there are no other weather systems lining up to deliver swell for the second half of the weekend. So aim to make the most of Saturday's swell in case Sunday's disappears from the charts.

Next week (Aug 31 onwards)

The complex low well south of the Tasman Sea from Friday onwards is a tricky beast to get my head around right now. With the models changing with each and every model run we really need a few more days to get a grip on next week's surf potential.

But as a baseline, we're still on target for a day or two of decent S/SE thru' SE groundswell around Monday and Tuesday (easing Wednesday), and the models are also suggesting another small closed low may form off the Far South Coast early in the week - possibly a source of fresh southerly swell too. Aside from this our other swell windows are relatively inactive. 

See you Friday!

Comments

thermalben's picture
thermalben's picture
thermalben Thursday, 27 Aug 2015 at 12:27pm

Looking rather tasty at Bondi!

Generic's picture
Generic's picture
Generic Thursday, 27 Aug 2015 at 6:26pm

Ben noticed a huge pulse of swell just on dark tonight easily 8ft + set came through bronte is there a new swell looked like a wave you would get on a south swell

acol's picture
acol's picture
acol Thursday, 27 Aug 2015 at 7:05pm

I saw the same sets come through Bronte this afternoon too

geoffrey's picture
geoffrey's picture
geoffrey Thursday, 27 Aug 2015 at 7:16pm

absolutely pumpeed this arvo

thermalben's picture
thermalben's picture
thermalben Thursday, 27 Aug 2015 at 8:13pm

Buoy data doesn't suggest anything unusual for the afternoon, certainly nothing bigger than what was seen during the morning.

deckstrus's picture
deckstrus's picture
deckstrus Thursday, 27 Aug 2015 at 8:30pm

I got cleaned up by an 8ft clean up set at outside Tama this arvo.

MHL is showing 16 sec period - and it felt like it.

thermalben's picture
thermalben's picture
thermalben Thursday, 27 Aug 2015 at 8:37pm

8ft as in genuine triple overhead?

deckstrus's picture
deckstrus's picture
deckstrus Thursday, 27 Aug 2015 at 8:53pm

I was out @ Tama on my own for 90mins and it was consistent 4—6ft and then this set of two waves came that were significantly bigger than anything else. Copped both on the head. Didn't think the second was ever letting me up again, totally smoked. Dunno Ben, was pretty solid.

Generic's picture
Generic's picture
Generic Thursday, 27 Aug 2015 at 9:04pm

Yeh it was around 550 huge from my perspective it was definetly triple overheard broke out the back way out and ran through to the bank and threw a huge barrel I was out their is the morning and the arvo was definetly more solid and powerful and it only got bigger until dark

thermalben's picture
thermalben's picture
thermalben Friday, 28 Aug 2015 at 7:15am

Unreal, thanks for the feedback guys. Certainly couldn't be ruled out due to the swell source (very intense polar storm in the Southern Ocean, with resulting long periods) but it seems to be an anomoly rather than a trend indicator. In any case this south swel has certainly performed well above expectations.

thermalben's picture
thermalben's picture
thermalben Friday, 28 Aug 2015 at 7:16am

Bondi still punching above its weight this AM.

And Newy on the pump again!