The Black Nor'easter: a historical study

Stu Nettle
Swellnet Analysis

The synoptic setup forecast to develop in the Tasman Sea this weekend has weather watchers agog. The configuration isn't overly rare, however it's the magnitude of this system – the size of the air masses and the pressure gradient between them – that sets it apart from similar events.

Technically, this type of system is referred to as an anticyclone intensification, and this particular one will result in a sharp jump in wave heights from the east-northeast for the East Coast. To get some further information on the setup Swellnet spoke to Associate Professor Ian Goodwin of the Marine Climate Risk Group at Macquarie University. Goodwin, a surfer from Sydney's northern beaches, worked on these notes with Tom Mortlock and Stu Browning:

This type of anticyclonic intensification produces a strong north-east windfield and east-north east storm waves over the western Tasman Sea. On average they occur about two days a year. The north-east windfield directing warm moist tropical air to the subtropics and mid-latitudes can combine with an upper level cut off low from the Southern Ocean.

The composite sea level pressure pattern for all east-northeast anticyclone intensification events over the past 30 years is below.

screen_shot_2016-06-03_at_10.46.19_am.png

The forecast pattern is most similar to the event of 23 April to 1st May 1989. In that instance the Easterly Trough Low (ETL) formed in the easterly airstream over the Coral Sea and northern Tasman Sea, and was associated with a strong subtropical anticyclone centred on Tasmania and the southern Tasman Sea (see images below).

screen_shot_2016-06-03_at_11.03.06_am.pngscreen_shot_2016-06-03_at_11.03.12_am.png

The peak storm wave conditions were observed at Brisbane, reaching wave heights (Hsig) of 6.11 metres and period (Tp) of 9.1 seconds. The duration of the storm wave conditions was 156 hours.

Peak storm wave conditions with wave heights (Hsig) of 5.87 m, 5.64 m, and 5.32 m were observed from the ETL on the 26th April at Byron Bay, Coffs Harbour and Crowdy Head, respectively.

As the ETL tracked south on the 27th and 28th April peak storm wave conditions with wave heights (Hsig) of 4.38 m, 3.72 m, and 3.83 m were observed at Sydney, Port Kembla and Eden, respectively.

Storm damage and coastal erosion from gale-to-storm force winds and high waves was recorded along the northern NSW and southeast Queensland coast. The north-facing coasts, called the southern hooks, of the coastline were most exposed and locations such as Byron Bay experienced severe coastal erosion.

Historically, this type of pattern is referred to as a ‘Black Nor’easter’ and was first recorded during the 1800s. It's possible that a Black Nor’easter was responsible for the grounding of the SS Wollongbar at Byron Bay on the 14th May 1921 when strong north-east gale force winds blew up. See sea level pressure field below.

screen_shot_2016-06-03_at_11.03.40_am.png

- Thanks to Associate Professor Ian Goodwin, Tom Mortlock, and Stu Browning of the Marine Climate Risk Group at Macquarie University.

Comments

crg's picture
crg's picture
crg commented Friday, 3 Jun 2016 at 5:16pm

Be interesting to see what happens to Belongil beach...more fodder for the rock wall debate...

SimoSurf70's picture
SimoSurf70's picture
SimoSurf70 commented Friday, 3 Jun 2016 at 5:20pm

I was gonna check Byron on Mon,Tue when wind swings. Should handle some wide lines. I got a gut feeling for Dixon and some fickle bombies North. Yeew

Blowin's picture
Blowin's picture
Blowin commented Friday, 3 Jun 2016 at 10:15pm

Why in gods fucking name would you broadcast where you think there will be good waves in the near future ?

Stupidity, ego or loneliness ?

Someone give this arrogant, dumb cunt a hug ASAP.

southey's picture
southey's picture
southey commented Friday, 3 Jun 2016 at 5:42pm

Its a very dynamic setup what price it doesn't come off as forecast , the Low drops down and then retro grades . ?
Nice story though .

" Gimme More Power "

freeride76's picture
freeride76's picture
freeride76 commented Friday, 3 Jun 2016 at 5:54pm

re: Belongil.

I've rarely, if ever seen such a large sand buildup on Belongil from the wreck to the mouth of Belongil creek.
If the storm bars form quickly Sat, the beach might be spared a real gouging.

AndyM's picture
AndyM's picture
AndyM commented Friday, 3 Jun 2016 at 6:18pm

Bet the land owners are shitting bricks.

freeride76's picture
freeride76's picture
freeride76 commented Friday, 3 Jun 2016 at 6:24pm

you know the rockwall is already there, right?

AndyM's picture
AndyM's picture
AndyM commented Friday, 3 Jun 2016 at 6:51pm

I would completely expect that with the right timing of tide and swell size and direction, rocks could start to shift.
Would you say it's out of the question FR?

freeride76's picture
freeride76's picture
freeride76 commented Friday, 3 Jun 2016 at 6:50pm

I very much doubt it, but the sand in front of it sure will erode.

but like I said, there is an enormous sand buffer there now.

AndyM's picture
AndyM's picture
AndyM commented Friday, 3 Jun 2016 at 6:52pm

As the weather starts to turn up...

AndyM's picture
AndyM's picture
AndyM commented Friday, 3 Jun 2016 at 6:54pm

I doubt it too, I'm just saying that if I lived there, I'd feel a slight puckering.

freeride76's picture
freeride76's picture
freeride76 commented Friday, 3 Jun 2016 at 6:59pm

great short story written by the late great Lester Brien about a couple guys wagering on a house still being there in the morning on the Belongil during the '54 cyclone, where the ocean waves/storm surge rolled down the main street of Byron.

AndyM's picture
AndyM's picture
AndyM commented Friday, 3 Jun 2016 at 7:02pm

Crazy shit can happen - will this be the one that punches through to the river in Wooli? Probably not but again, would you bet the house on it?

Can you post a link to that story?

wingnut2443's picture
wingnut2443's picture
wingnut2443 commented Friday, 3 Jun 2016 at 6:20pm

Fuck 'em, they can afford it.

Surfboard Design and Construction Kook. Evidence is here: www.ffwsurfboards.com.au
*FFW - Few Fun Waves ... that's what it's all about for me.

batfink's picture
batfink's picture
batfink commented Friday, 3 Jun 2016 at 6:34pm

Possibly some, but quite a few are probably still in the hands of people who bought many moons ago and don't have the wherewithal to stump up a few $100k or more for repairs.

Try to keep your schadenfreude to a minimum. :- |

tworules's picture
tworules's picture
tworules commented Friday, 3 Jun 2016 at 6:21pm

one time ne swell was consistent, now its the big deal!

batfink's picture
batfink's picture
batfink commented Friday, 3 Jun 2016 at 6:36pm

"however it's the magnitude of this system – the size of the air masses and the pressure gradient between them – that sets it apart"

That's it stu, the gradient and length, from that direction, I haven't seen for a long time, if ever.

If it was from the south, meh, fairly strong but not untypical southerly monster, but this is a beast from the north.

Will be interesting to look at south end 'bra come next week.

tworules's picture
tworules's picture
tworules commented Friday, 3 Jun 2016 at 6:49pm

only time we ever shut the backdoor,was in a black ne,er

MartinNow's picture
MartinNow's picture
MartinNow commented Friday, 3 Jun 2016 at 6:54pm

I first heard the expression "dirty black nor easter" from Barry V Stark who was a well known knee boarder / fisherman / lure maker / yarn spinner (all lies!) / gem, late of Woombah, who used to knock around with surfings legends of the 60s. RIP Bazza! I got to surf a wonderfully clean and solid NE swell at Coalcliffe Bombie in about 1975 until about 2100 one Friday night under a full moon. It had cleaned up incredibly and was green glass. Could history repeat?

tworules's picture
tworules's picture
tworules commented Friday, 3 Jun 2016 at 7:08pm

its on the new moon this year, and i hope you got to north's before closing

MartinNow's picture
MartinNow's picture
MartinNow commented Friday, 3 Jun 2016 at 9:57pm

I think we just crashed in the old slsc clubhouse - coupla hot ones helped. Not too long after that the club house fell into the sea. I saw my mates fall with the kitchen floor and fridge and stove into a very high tide!

Sheepdog's picture
Sheepdog's picture
Sheepdog commented Monday, 6 Jun 2016 at 7:24pm

"The Black Nor'easter".......

I don't think I've read bullshit like this here since, jeez, the last time I read bullshit like this here.......

Sheepdog

wellymon's picture
wellymon's picture
wellymon commented Monday, 6 Jun 2016 at 10:20pm

Sheepdog wrote: "The Black Nor'easter".......

I don't think I've read bullshit like this here since, jeez, the last time I read bullshit like this here.......

Alot more informing than your political waffle Sheepio ;-P

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 .

Blowin's picture
Blowin's picture
Blowin commented Monday, 6 Jun 2016 at 10:31pm

Got a glimpse of the gold on offer on the West coast of your Death Island yet ,Welly ?

Supreme fun .

All work and no play makes Welly a dull boy.

Try hitting up one of the WAPET production boys and get them to take you on a little surfari on your RDO .

Shhhhh !

wellymon's picture
wellymon's picture
wellymon commented Tuesday, 7 Jun 2016 at 6:58am

Haha looks good Blowin.

Out of bounds :(

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 Monday, 6 Jun 2016 at 10:54pm

You read that stuff? A non naturalized kiwi reading threads on Australian politics? Jesus.... You'll be following the wallabees next...... Be careful bruh..

Sheepdog

stunet's picture
stunet's picture
stunet commented Tuesday, 7 Jun 2016 at 7:23pm

To Martin, I'm deleting your comments (as I also did in the East Coast thread) because that photo doesn't mention the waves name for a reason.

Be cool, man.