Off the charts: The mystery of mysto swells

Craig Brokensha
Swellnet Analysis

“Bear knew where the waves came from and why.”
- Big Wednesday, 1978

A lot of things have changed in the surfing world since Big Wednesday first hit the movie screens. In 1978 professional surfing was in its infancy, most people rode single fins, and surf forecasting was a rudimentary art consisting of equal parts science, intuition, and sheer pot luck.

Some surfers had a handle on the basics of surf forecasting, they could predict swells created close to shore or from a frontal system. Yet every so often a swell would hit the coast from no obvious source. They were mystery swells, and due to modern day surf forecasting they are practically a thing of the past (cue grumbling from the surfing Luddites).

This brings us to the very long-range easterly groundswell due this Sunday and Monday across Australia's East Coast. Even ten years ago this swell would have been hard to spot, and in Bear's day it would have seemingly arrived out of nowhere.

Before the internet, amateur surf forecasters used the synoptic charts in the local paper provided by the Bureau of Meteorology. They'd try and get an edge on the rest of the surfing population who'd just rock up at the beach day after day, dealing with what they were given.

The BOM's charts were fine for forecasting swells generated within Australian waters out to 2,000km (a distance to about New Zealand and halfway to Heard Island) but were useless for longer-range swells from the Western Indian Ocean or greater South Pacific Ocean. Those swells were literally off the map.

Last weekend's swell, which formed between Fiji and New Zealand, could have been forecasted by monitoring the BOM weather charts, as Ex-Tropical Cyclone Lusi sat just on the right hand edge of the charts (top image). Keen-eyed surfers would've known a swell was coming.

But have a look at today's chart (middle image) and you'll see nothing of significance anywhere east of the Australian continent. There's only a weak high pressure ridge across the Coral Sea and a polar frontal passage south-west of Tasmania and Victoria. It would appear there's nothing of interest in our swell window.

However, if you look at Swellnet's WAMs (bottom image), which extend out an extra 5,000km further east of the Bureau charts, you will spot a significant tropical synoptic setup around the Cook Islands. This is Tropical Cyclone Mike and it's moving slowly south into a broad and strong trade-flow created by a large stationary high east of New Zealand. It's a great swell-producing system and it's totally off the BOM's weather charts.

The distance between Tropical Cyclone Mike and the Australian East Coast is about 4,600km, with the swell expected to take three to four days to reach Northern NSW and South-east Queensland. If a surfer was only looking at the BOM charts they'd have no idea where this swell had come from. A mystery swell indeed. But with access to better charts we now truly know where this swell is gonna come from and why.

                                                                                       --------------------

As an end note, we can't stress enough how inconsistent this groundswell event will be. This system is twice as far away as Tropical Cyclone Lusi, so if you thought there were long lulls during last weekend's swell this next swell will see twice the inconsistency with waits of up to 15 minutes and not much in between. So prepare to be patient and also take that extra ten minutes to watch the surf before paddling, just to get a better picture of what the ocean is doing. //CRAIG BROKENSHA with STU NETTLE

Check your local forecast here:
Gold Coast
Ballina
Coffs Harbour
Newcastle
Northern Beaches
Cronulla
Wollongong
Ulladulla

Comments

grazza's picture
grazza's picture
grazza commented Thursday, 20 Mar 2014 at 1:49pm

It would be a truly excellent week to set up camp in say Whangamata or Gisborne. Once the North Island intervenes, we lose connection with the source, but this system would just keep on giving to East Coast NZ.

I for one miss the mystery swell days. It's nice to know, I'd just rather no one else did...

Tim Bonython's picture
Tim Bonython's picture
Tim Bonython commented Thursday, 20 Mar 2014 at 1:59pm

Pity about the winds but there will be pockets & in the early hours there will be places.

sunlover199's picture
sunlover199's picture
sunlover199 commented Wednesday, 4 Apr 2018 at 12:29pm

plenty of pockets goin off in South Oz Desert this week and this month, all welcome bring your cameras and the crew !

dellabeach's picture
dellabeach's picture
dellabeach commented Thursday, 20 Mar 2014 at 4:37pm

Please never use "would of" again. Thanking you in advance.

thermalben's picture
thermalben's picture
thermalben commented Thursday, 20 Mar 2014 at 4:53pm

Ah, the grammar police are on the beat! Well spotted DB (jeez, you're more pedantic than me).

dellabeach's picture
dellabeach's picture
dellabeach commented Thursday, 20 Mar 2014 at 5:11pm

Believe me, it's a curse. Life would be more enjoyable if i could simply ignore "loose" used in place of "lose", "your" rather than "you're" and don't get me started on "there, their, they're". I will however practise patience, in preparation for the expected long lulls during this next swell.

Craig's picture
Craig's picture
Craig commented Thursday, 20 Mar 2014 at 5:18pm

I fall into those traps all the time re loose and lose. All over the should've and would've though, thanks for pointing it out, never new that. Jokes, knew.

thermalben's picture
thermalben's picture
thermalben commented Thursday, 20 Mar 2014 at 5:45pm

Here ya go DB, a special forum thread just for you!

https://www.swellnet.com/forums/wax/100116

zenagain's picture
zenagain's picture
zenagain commented Thursday, 20 Mar 2014 at 7:23pm

Della, you used a lower case 'I' when referring to the first person. Namely yourself.

Life would be more enjoyable if i could simply ignore "loose" used in place of "lose",

Such grammatical sloppiness will not be tolerated on these forums young man;)

Watashi wa metabo oyagi desu.

dellabeach's picture
dellabeach's picture
dellabeach commented Friday, 21 Mar 2014 at 8:54am

zenagain wrote: Della, you used a lower case 'I' when referring to the first person. Namely yourself.

Life would be more enjoyable if i could simply ignore "loose" used in place of "lose",

Such grammatical sloppiness will not be tolerated on these forums young man;)

Happy to be among my own. Thank you Zen, I stand corrected.....yet again.

zenagain's picture
zenagain's picture
zenagain commented Thursday, 20 Mar 2014 at 7:28pm

Nice use of Alliteration in the last sentence though.

Watashi wa metabo oyagi desu.

stunet's picture
stunet's picture
stunet commented Friday, 21 Mar 2014 at 8:12am

Sorry Zen, gotta pull you up for Arbitrary Capitalism.

zenagain's picture
zenagain's picture
zenagain commented Friday, 21 Mar 2014 at 11:23am

That's true Stu, you got me there.

Please correct me if I'm wrong but isn't the correct term 'Arbitrary Capitalization'?

;)

Watashi wa metabo oyagi desu.

stunet's picture
stunet's picture
stunet commented Friday, 21 Mar 2014 at 11:31am

Smarmy bastard. I'd pull you up on the use of a 'Z' instead of the regionally correct 'S' except you're not in this region and I've got nothing else to call on. 

Think I'll quit while I'm behind and hope I've spelled everything correctly...

 

kaiser's picture
kaiser's picture
kaiser commented Thursday, 20 Mar 2014 at 5:25pm

it's and its.

It's only ever applies if it is short for 'it is'

Overuse of apostrophes is rampant.

thermalben's picture
thermalben's picture
thermalben commented Thursday, 20 Mar 2014 at 5:27pm

Don't get me started.

wellymon's picture
wellymon's picture
wellymon commented Thursday, 20 Mar 2014 at 5:53pm

dellabeach, sorry but whose give's a fuk about spelling, these is not a spelling comp, some of os never hat amasing whriting skilles like youse.
Be patient :)

Patience serves us against insults precisely as clothes do against the cold. For if you multiply your garment as the cold increases, that cold cannot hurt you; in the same way increase your patience under great offences, and they cannot hurt your feelings.

Good article Craig, really do appreciate your WAMS.
Back to back swells about time, patience is a good thing, I believe matures wiith age.

Our brains are too small at the moment to comprehend the reality of what's happening in our forests . We're only just waking up so to speak . The big problem is we think we know everything, we are specks of dust on a timeline and we know nothing .

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Thursday, 20 Mar 2014 at 6:08pm

Well here's what I reckon............... Only kidding ;)

Sheepdog

plasm's picture
plasm's picture
plasm commented Thursday, 20 Mar 2014 at 6:27pm

I remember many years ago (probably 10) a similar swell was forecast for the east coast but it just never showed up. I think the synoptic setup was similar to this one but it was even further to the east (probably why). Anyone remember that one and the reasons why it never made it to shore other than distance? This will test the memory banks.

Craig's picture
Craig's picture
Craig commented Thursday, 20 Mar 2014 at 6:33pm

That's another thing that should be pointed out with these long-period groundswells.

Because they start to interact with the ocean floor at quite some depth and distance offshore they usually focus into some spots, and are deflected away from others.

This was seen at even single beaches on the last swell event, with some breaks raking in all the size, while others were half if not smaller.

So I would say that could of happened in your local area plasm, or just that the swell was too far away and experienced too much swell decay on the way to the East Coast.

We are very cautious about this up coming swell, and if we rated the Sunday/Monday swell around Southern NSW as 9-10/10, then this one will probably be more in the 6/10 range due to the smaller size, less consistency and also less than perfect winds.

Craig's picture
Craig's picture
Craig commented Thursday, 20 Mar 2014 at 6:44pm

Here's a real crude overlay of the BOM chart region and how much further this storm falls outside of this area.

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Thursday, 20 Mar 2014 at 7:01pm

Hmmmmmm...... Interesting call.....

Sheepdog

dromodreamer05's picture
dromodreamer05's picture
dromodreamer05 commented Thursday, 20 Mar 2014 at 9:17pm

On the bright side this is the lazy bastard surfer's (me) wet dream, i can paddle out without getting my expensive hair product washed out straight into a stand up pit with just enough chandelier coming down to get that wet but not drowned rat look....

batfink_and_karate's picture
batfink_and_karate's picture
batfink_and_karate commented Thursday, 20 Mar 2014 at 10:51pm

"So I would say that could of happened in your local area plasm"

Could of, could of??????????? You had just been warned Craig, and you put that out there. I hope you were being facetious young man (facetious, the only word in the English language with all the vowels in alphabetical order!)

Anyway, where was I, oh yes, you egregious young upstart, get your act together.

On a slightly more mysterious note, even with all the information we have, there are still mysterious swells that appear now and then, and I kid you not. I have been tracking these things since we now have access to much wider maps, and I can tell you that there have been a number of swells, less than a handful, that have come in over the last 5 years, that have had no explanation whatsoever.

From Craig, from Ben, from anyone. I know, I asked them.

The mysto swells are not gone, just less likely.

Craig's picture
Craig's picture
Craig commented Friday, 21 Mar 2014 at 8:14am

Oh Jeez, this is going to take a while to re-wire my grammar.

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Friday, 21 Mar 2014 at 8:53am

Craig... You write, "As an end note, we can't stress enough how inconsistent this groundswell event will be."
Was just looking at my "hail mary" posts from the 12th re' this swell.
It will be inconsistent, Craig, no doubt.... But not as inconsistent as most swells from that region....... Cheers.....

Sheepdog

Craig's picture
Craig's picture
Craig commented Friday, 21 Mar 2014 at 9:03am

Sheepdog, we hardly receive noticeable swell energy from this region.

I can't even remember the last time we received swell from this distance on the East Coast.

When the swell's generated that far away, the main point is that it will be extremely inconsistent compared to closer-range swells most East Coasters are used to.

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Friday, 21 Mar 2014 at 9:38am

Yeah, Craig.... IKR........ South of about Anga orCoffs will be very inconsistent, if not a hoax swell... But Byron to Fraser well be slightly different, not as inconsistent as one may think.... I'll take my opinion over to Swell net forecast notes, if you are interested, Craig.
Otherwise, fix those dings, mate, and get out early on the 25th, still the best day in my opinion...

Sheepdog

ACB__'s picture
ACB__'s picture
ACB__ commented Friday, 21 Mar 2014 at 9:51am

I love inconsistent swells. It gives me lots of time to start lots of conversations with all the friendly surfing tradies on the Northern Beaches!! always so well received.

the-u-turn's picture
the-u-turn's picture
the-u-turn commented Friday, 21 Mar 2014 at 11:06am

...writing a paper at the moment and checking the grammar as I (me, one) goes.

luv you'se work, dellabeach and zennagain.

The U Turn
...a little Aloha goes a long way.

mitchvg's picture
mitchvg's picture
mitchvg commented Friday, 21 Mar 2014 at 12:33pm

So what's up with Newy being 3-4ft SE today? That seems a bit mysto.

blueberrybill's picture
blueberrybill's picture
blueberrybill commented Saturday, 22 Mar 2014 at 8:51pm

mitchvg wrote: So what's up with Newy being 3-4ft SE today? That seems a bit mysto.

exactly mitchvg! I've been wondering the same thing. Thursday 20th we had a good size fun SE ground swell (1hr nth Newcastle) and all the models predicted 1-2ft E swell. How do the models miss a 4ft ground swell that lasts nearly 2 days? It happens here a bit?!

mitchvg's picture
mitchvg's picture
mitchvg commented Sunday, 23 Mar 2014 at 7:44pm

Yeah must just be those swells generated under Tassie somewhere, finding their thrill on their way to Fiji.

BringOutTheGimp's picture
BringOutTheGimp's picture
BringOutTheGimp commented Saturday, 22 Mar 2014 at 6:17pm

Are Gina or Clive rich enough to mine the North Island of New Zealand completely off the charts and out of my SE swell window? I have had enough of that useless land mass cutting swells short and interrupting so many, perfectly good, long range, "mysto" swell generating fetches. Even in the short term, TC Mike's swell will be cut shorter than is necessary... All the Kiwi's are living and working on the Gold Coast now anyway- piss the North Island off and outta the road already!!!

udo's picture
udo's picture
udo commented Saturday, 22 Mar 2014 at 7:51pm

@sheepdog, hows the 25th looking ? you still calling it ?

OK Anti vaxxers ------------ Now is your chance to go to China and prove us all wrong

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Saturday, 22 Mar 2014 at 9:31pm

Udo.... Called that waaaaay back on the 12th..... 4 foot.... yeah, reckon it'll be 4 foot+. Asked Don weather to give me 24hrs each side of the 25th, seeings I called it 13 days early.... But Don's a tight arse.... (luv ya don ;) ) lol
Probably peak on the 24th early, but should hang in till the 26th..... Shame about the winds, udo..... I think real early though, on the 25th, it could be ok.
Check this map - 0700 tues - quite a slack gradient over the sunny coast with rain... Outer points at that secret spot north of brisbane lol

http://www.metvuw.com/forecast/forecast.php?type=rain&region=swp&noofdays=7

Sheepdog

blindboy's picture
blindboy's picture
blindboy commented Sunday, 23 Mar 2014 at 7:51pm

Well there was certainly no mystery about this evening's late boost of swell in Sydney. Full parking areas all up and down the northern beaches! I have to say that the accuracy of the swell predictions has become a factor in concentrating the crowd and it is likely to get worse given that the future direction of forecasting generally is not so much longer term as more precise local data. Oh shit, watch out for the 5.05pm set!

mick-free's picture
mick-free's picture
mick-free commented Sunday, 23 Mar 2014 at 8:06pm

Blindboy just makes it all the more rewarding when you score it uncrowded. Unfortunately even Sky News Weather were pumping Manly as the place to be today, and it was super crowded

Mick Free FIFOFOMO

thermalben's picture
thermalben's picture
thermalben commented Tuesday, 3 Apr 2018 at 4:58pm

There's no doubt that had today's synoptics occurred fifteen years ago, the inbound E'ly swell due this Thurs/Fri Sat would be attributed to TC Iris in the Coral Sea.

When in actual fact it will have been generated by TC Josie, in the South Pacific.

Here's a rough overlay.

batfink's picture
batfink's picture
batfink commented Tuesday, 3 Apr 2018 at 6:10pm

Nice thread revival Ben.

freeride76's picture
freeride76's picture
freeride76 commented Wednesday, 4 Apr 2018 at 6:26am

Just as an aside, I don't think I've ever seen better looking synoptics deliver shittier surf.

Wharfjunkie's picture
Wharfjunkie's picture
Wharfjunkie commented Wednesday, 4 Apr 2018 at 11:24am

"(cue grumbling from the surfing Luddites)."
Those who are profiteering from surf forecasting and the way the information is published to the public would surely not call anyone questioning the impact their website has on crowds in the water "Luddites" would they.

Collect that revenue boys and who gives a stuff about the negative impact it has when you encourage people to visit certain coastline on certain days.

thermalben's picture
thermalben's picture
thermalben commented Sunday, 26 Jan 2020 at 2:49pm

Ignoring for a moment the (generally unfavourable) local winds, the current E'ly groundswell across the East Coast would have definitely been a contender for 'mystery swell', but adding further confusion would have been the presence of TC Tino a week ago.

To recap: TC Tino first began to develop near the Solomon Islands around Jan 11 but didn't reach TC category until Jan 16. It was always too far east for the regular BOM charts but first appeared on the BOM's Pacific Ocean MSLP Manual Analysis on Jan 17 (see examples of both below).

Now, try to wrap your head around the orientation of the Pacific chart - I can't without turning my head on its side, and even then it's impossible to have any sense of accuracy in its position. And, it wasn't until the next day (Jan 18) that TC Tino emerged from the Fijian swell shadow; I reckon it would have been impossible to deduce from those map projections anyway.

Anyway, the 'off the charts' part is only half of the fascination here.

Those who read my QLD FC Notes will know that the early TC-classified stage of this system wasn't favourable for swell production, and that it was only meant to develop an enhanced E'ly fetch once it had turned extra-tropical - by which time it had fallen into the swell shadow of New Zealand.

Primary swell production occured around Jan 20/21 (see charts below for the 20).

And, here's the corresponding BOM chart for Jan 20.

Now, imagine the viewpoint from someone watching the surf in SE Qld.

New swell lines start showing through Friday 24th, and then hold through Sat 25th and Sun 26th. A three-day E'ly groundswell event is not as regular occurrence as you'd think, so it would have stood out to keen observers.

The Tasman Sea synoptics via the Courier Mail (probably in use at at the fish and chip shop by this time) would have shown no possible sources, but if you had access to the BOM's Pacific charts, you would have noticed TC Tino way out east of Fiji way back on Jan 17 - seven days prior to the start of the swell making landfall (and nine days prior to today, when the E'ly swell is still showing nicely).

Now, it doesn't take 7-9 days for an easterly groundswell to arrive from the other side of New Zealand. It only takes 4 days for a decent trade swell, and less for a longer period groundswell (because they travel faster).

So, there would have 'kinda' been an explanation to a handful of people - maybe a delayed swell from TC Tino? - though it wouldn't have really made sense. And to everyone else, it would have been a proper mystery swell.

And how about those people in Southern NSW who have also picked up long period E/NE swell from this system, located on the other side of NZ? It's one of those "no possible chance" weather charts that require a lot of extra scrutiny to have any hope in believing there's any possibility that SE thru' E/SE swell energy would have traversed the North Island and come back into Southern NSW out of the E/NE.

freeride76's picture
freeride76's picture
freeride76 commented Sunday, 26 Jan 2020 at 3:02pm

frustrating motherfucker trying to find a rideable wave off it though.

simba's picture
simba's picture
simba commented Sunday, 26 Jan 2020 at 4:29pm

yea cunt of a swell with shit winds here.

simba

thermalben's picture
thermalben's picture
thermalben commented Sunday, 26 Jan 2020 at 4:33pm

"Jellyfish shit winds", in the proper vernacular (apologies Sheepdog).