Dicey conditions until Saturday, better options Sunday onwards

Ben Matson picture
Ben Matson (thermalben)

Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Wednesday 20th May)

Best Days: Fri AM: possible a small window in the morning before the onshore hit (keep your expectations low). Sun: improving winds and abating S'ly swells. Mon/Tues: small S'ly swells and light winds. Late Tues and (more likely) early Wed: small SE groundswell with light winds. 

Recap: Minor southerly swells pulsing intermittently over the last two days, albeit small in size. Good conditions with light winds on hand.

This week (May 21 - 22)

Not much surf is expected on Thursday. There’s been no new swell generating systems in our swell window over the last few days, so tiny conditions are expected to persist with freshening W/SW tending SW winds. 

However, a strong cold front is presently racing through the Southern Ocean and into the lower Tasman Sea, and this is generating a new S’ly groundswell that’s due to build during Friday. Because the front has been sped up since Monday’s notes, the associated swell’s arrival time has also been pulled forward. Model guidance has the leading edge in mid-late morning (Tp likely to be around 17-18 seconds), with a steady increase in size expected into the afternoon, around 4ft+ by close of business. 

However, local winds look pretty dicey. A low pressure system is modelled to form off the coast during Thursday, and strong S/SE winds will envelop the coast on Friday - probably around the same time the (unrelated) groundswell starts to muscle up (early guidance suggests around midday). These winds will also generate a choppy windswell of a similar size (3-5ft by the end of the day) but most beaches picking up any appreciable size are likely to be very choppy. 

So, the only real options for Friday will be early morning while winds are SW - but surf size will be very small at this time - with a possible window late morning as the new S’ly groundswell starts to build but before the low moves across the coast, bringing strong S/SE winds.

Otherwise, Friday's only other possibility will be late afternoon inside a sheltered southern corner where i’ll be much smaller but at least cleaner on the surface.

This weekend (May 23-24)

Saturday looks rather poor for surfing. The Tasman Low is expected to slide quickly to the east, so the pressure gradient will quickly ease however we’ll still be under a mainly fresh S’ly breeze (maybe a few pockets of early SW winds but don’t hold your breath).

Surf wise, Friday’s S’ly groundswell and S/SE windswell will also be easing but south facing beaches should still see 3-4ft sets (bigger in the Hunter). Keep your expectations very low.

On Sunday, we’re looking at much better conditions with mainly light winds across most coasts, although there may still be a few lumps and bumps from Saturday’s winds.

The easing swell trend evident on Saturday will be reinforced by a small, long range pulse of S’ly swell from a frontal belt in the Southern Ocean but no great size is expected - just an occasional 2-3ft set at south facing beaches, with smaller surf at remaining beaches. The Hunter coast should see bigger waves in the 3-4ft range at times but it’ll be inconsistent. Overall, there should be some fun waves on offer to finish the weekend.

Next week (May 25 onwards)

We’ve got plenty of small southerly swell lining up for the first half of the week, thanks to a very active frontal progression that’s expected to slam New Zealand’s South Island for several days. Most of these systems won’t be very well aimed for us, but we should still see inconsistent surf in the 2ft+ range at south facing beaches on Monday and early Tuesday, and light winds will maintain clean conditions. Expect bigger surf in the Hunter.

Late Tuesday (and more so into early Wednesday) a new SE groundswell is expected to make landfall, originating from a polar low SE of New Zealand - one of our funky swell windows - that’s expected to push up into the broader frontal streamflow later Saturday and into Sunday. Despite the lengthy travel time, we should see inconsistent 2-3ft sets from this source at exposed beaches and with light winds on hand there should be some great waves at most open coasts.

Otherwise, a large blocking high through the Tasman Sea during this period suggests we could be heading towards a spell of much smaller conditions through the second half of next week, and possible next weekend. More on this in Friday’s update.

Comments

belly's picture
belly's picture
belly Thursday, 21 May 2015 at 12:56pm

Ben, do you think the South Coast might display some more favourable conditions on Saturday? I'm thinking there might be some more east (and size) in the swell from the fetch generated on the southern flank of the Tasman low through late Thurs into Fri.
Cheers!

Craig's picture
Craig's picture
Craig Thursday, 21 May 2015 at 1:15pm

Looks like the strength of the low has increased, as well as the favouable in-feed of E/SE winds on its south-eastern flank.

I think the weekend is now looking quite good, if not better if you can find somewhere out of the wind.

thermalben's picture
thermalben's picture
thermalben Thursday, 21 May 2015 at 1:41pm

Yeah latest model runs have upgraded.. But it's just one model run. Will need to keep a close eye on this arvo's 00z and tonight's 12Z run.

nickg's picture
nickg's picture
nickg Thursday, 21 May 2015 at 3:26pm

nice. I had a look at the synoptic this morning and was going to ask the question here about the potential for a bit more east swell than was originally forecast. it whips away pretty quickly but it heads due east so hopefully the fetch has enough time to generate something.

JackGregory's picture
JackGregory's picture
JackGregory Thursday, 21 May 2015 at 3:11pm

hey ben whats your opinion on saturday morning and is there gonna be S'ly winds or a bit more west in it ?

Craig's picture
Craig's picture
Craig Friday, 22 May 2015 at 3:23pm

What a rapid jump in size. Most of Sydney looks to be in the 6-8ft range, with Newy even bigger. Looks like the large swell spike has alrady peaked already in Sydney though with Wollongong already looking a bit smaller than late this morning.

ASCAT is quite impressive with winds up to 40kts right off the coast.