Developing superbomb in the Indian Ocean
As most of the East Coast sits waiting for the first decent swell of the year, it's of interest to cast our eyes over into the Indian Ocean and in particular, a pair of tropical cyclones.
An active phase of the Madden Julian Oscillation (MJO) across the western Indian Ocean has spawned two tropical cyclones, Ava off the Madagascar coast and the more intense Irving which is west-southwest of Cocos Islands.
As Ava stalls off the south-east tip of Madagascar today, Irving will make a bee line south-west but come tomorrow, Ava will be drawn like a magnet east-southeast on a collision course with the then southward tracking Irving.
When two volatile and energy charged cyclones combine in the Southern Ocean along with an infeed of cold air from the upper atmosphere, the end result can only be something of significance.
Regular Swellnet readers will be familiar with the weather term 'bombing low,' that being a low that drops 24hPa or more in central pressure within a 24 hour period.
The exact meteorological definition is that this 24hPa drop in 24 hours occurs at 60degrees latitude (called 1 bergeron), but if the storm is at a lower latitude (more towards the equator) less of a pressure drop is required for it to be classified as a 'bomb'. For example at 25degrees only a drop of 12hPa is needed for it to be classified as a 'bombing low.'
This is because storms in the polar regions usually exhibiting less strength (from a comparable pressure drop) due to the effects of latitude. When looking at a synoptic chart, if we have the same isobar wind spacing across the Gold Coast and Victoria, the winds will be stronger across the Gold Coast due to this latitudinal effect.
The storm in question is forecast to drop a phenomenal 47hPa in 24 hours at a latitude of 40-45 degrees south. At this latitude the low only needs to drop approximately 18hPa in 24 hours to be classified as a bomb, but it will clearly surpass this, intensifying at 2.6 bergerons.
As the intensification will be greater than 2 bergerons we'll see this storm fall into the superbomb/ultrabomb classification which is very rare. The last time I can recall a system like this locally was March 2007 - almost ten years ago - when the BOM issued their first ever hurricane wind warning for Southern Australian waters (read Alex Zadnik’s article here).
But moving away from the geeky weather talk, what most want to know is how much swell it will produce.
Current forecasts have the ultrabomb generating a fetch of storm-force W'ly winds (possibly reaching hurricane force) as it dips south-east through the Indian Ocean.
While the south-east track of the low isn't ideal, the slow moving nature and pure wind strengths will help generate large long-period surf ranging from Sumatra to southern Australia, with smaller very inconsistent energy filtering into New Zealand and Fiji.
A peak in size is expected across Western Australia on Monday afternoon (12-15ft Margaret River) with favourable morning winds, while Indonesia should see the swell mid-week, peaking to 8ft on the sets across swell magnets around Bali (smaller west of Java).
Coming back to the East Coast, and the MJO which is the source of tropical instability (namely cyclones) is forecast to move more towards the Australian region in the coming fortnight though it will be weakening. Ben Matson will provide updates on this in the East Coast forecaster notes over the coming weeks.
Comments
You had me at 2.6 bergerons. Great synopsis Craig.
Mmmmm... Bergerons.
I love these articles.
Be interesting to see how big it comes in at.
Track looks very sub-optimal for major swell development as the fetch moves quickly and obliquely wrt to the swell window.
Actually after the initial south-east dip is stalls and aims a sustained storm-force W/SW fetch for about 24 hours from Friday morning through Saturday morning towards Australia before veering more polar.
It could be better but it's still significant.
Could you put one about a thousand nautical miles due east of Brisbane please.
Bongon, Beeron, Bergeron. Sounds like a great night out to me.
But seriously, that is an amazing piece of weather, very nice. Thanks for the learning, never knew.
That was fkn cool! So in theory winkipop and bells are about to get the first cyclone swell of the year.. Kind of..
Hope so!
Pack your guns I have a feeling wensday could deliver a wiamea like day at a secret spot in Victoria! With a beach break near bells becoming like pipe/backdoor a wave in Port Phillp doing its best indo impressions and the usual suspects in cat bay purring into the arvo..
Sucks I'm in NSW...
Yeah woof, if it is a se and it cranks there will be a garzillion surfers at you know where. Bank is really average out there but it won’t stop the west coast invasion.
Bahaha, Sheddy Eddy reckons its a secret spot......West Coast guys reckon they own it anyways cause you can see it from Lonny
Cat jumped out of that bag in the 80s
Hardly a secret spot it's just that people fucking go crazy when you say the name!
Like Easter reef whoops..
Easter reef? Must be 2 mile from where Campbell gets his Port from on the other side of the dozen old blokes....
Fuck I dig being cryptic.
Lol hey Tarzan how funny is it when all these people go proper Loco over well known waves that have been documented and talked about in mags and movies for decades.
The funny thing is while all these idiots are woffling on about not talking about well know spots the smart guys are smiling and surfing the epic secret spots just around the corner..
You me and anyone can get waves anywhere as long as you drop your football mentality and don't Chase a wave like the pack as if it's a football.
(snapper not included)
Who’s Sheddy Eddy?
Yep! What a shame the eastcoast of Victoria is not littered with offshore bomboras like Beacon..
Would prove to be Australians Hawaii other wise.
"Superbomb" - sounds a bit Higgins Storm Chasers Craig.
What are the implications for the SA coast, will it be too west to get in to the south coast, or will that turn back towards the continent (referred to above in the comments) send some swell up to Victor from a more SW orientation?
Not that it matters to me over here in Spain...
Ouch.. the Higgins slight stings a little.
But in all seriousness, check the link to Alex Zadnik’s article from ten years ago. Stuart Coombs - respected BoM Forecaster - referenced the terms ‘superbomb’ and ‘ultrabomb’, with quite an elegant description too.
Ha, thought that might hit you where it hurts Ben. Just dumb luck when actual science aligns with the perfect clickbait headline.
Indeed. We’ve been waiting ten years for this bastard to come around again!
So that's a Northern and now Southern Hemisphere weather "bomb" event this month!?
at least he didn't say Bomb Cyclone
Hmm the last proper "Bomb" event in NSW was about 6-7years ago when a low drifted offshore around the gong.
We woke to 6-8ft pipe like beachs quickly getting out off control and rising to 12ft+
I was out at south beach and it got so big the rips where psycho and 12+ things started landing all over place..
Couldn't catch one on my 6'3 because of the water being sucked out.
Took a scary hour to get in.. A broken leggy that day would have spelled death..
Only 3 of us surfed the golf course that day..
Sandon point held a boardriders that day..
The swell was dead east and a westerly blew all day..
Heavy day.. But perfect..
Settle
No chance I'm "excited" for you guys and I'm not even there.
These events are like Santa for me..
Whether it's just seeing pictures of waves that I have been to around Australia online or I'm there..
Clubbies going to be busy on this side of Tasman.
Cool love these unique systems wonder if this will light up fanning wave?
ID: "wonder if this will light up fanning wave?" - what, the one in NW Africa?
;)
I think we've all woken up to the fact that Huey is on his Summer Surf Safari.
That can only mean Captain Goodvibes & Astro are at the helm.
Bombs! Of course you get Bombs! Pig of steel tosses H-TYPES overboard! *Surf's up.
For all we know it's Huey that drives Goodvibes around the bend at the end of the day.
That's a fact seldom shared...[SN-1st]
Good stuff, Craig - and thank you for not calling it a 'weather bomb'!
We just had a bombing low cross NZ - just in time for the holidays, as usual - and mysto spots in weird places lit up.
For those of you hoping for giant Winki/Bells, look up 'Dynamic Fetch' and check your Great Circle trajectories. Could be some interesting reading.
Do you have a reference article or site I can read about this..
Can't quite find it.
Woof woof, I'll have a look tomorrow. Frantic evening at work issuing warnings for heavy rain in NZ :-)
where was good?....what mysto spots?...I was in Nz on the chase. I didnt think there was any fetch to light up spots but I'm happy to be proven wrong. got some good action but not from that low. I was in Langs beach fri morning onshore wedgues
Island bay pumping was it island bay
Next swell due in 2025
Think South Island and impossibly sheltered...
Latest updates have the bombing low slightly weaker but just sneaking into the 2 bergerons category, dropping from 967hPa to 931hPa in 24 hours, and bottoming out around 928hPa.
The low is also less favourably aimed for Indo but still good for southern Australia.
Looking forward to seeing how this turns out.
Haven’t had 8ft waves and offshore winds together for a while now
What area/coastline are you from goofy?
Melbourne
Well fuck yeah! That's where I grew up...
OK we can be friend's.
I noticed the charts have halfed in size for the Mentawai, do you expect them to increase the outlook for next week?
Nah, unfortunately the low is now forming a little too late and west for Indonesia and aimed more towards the south of Australia.
Woooo I just have this feeling that Victoria is going to make the most of this swell over all..
lot of froth over nothing if you ask me.
i remember surfing the one in 2007@torquay i cant remember where the storm or fetch was but it was 6-8ft &choppy with a sw wind...the last one was in a similar position to this but the low traveled down the west coast and bombed @ the bottom left of wa in a slightly better position than this current one is forcast ...i surfed west victoria it was straight as a ruler groomed with an offshore wind and size was DOUBLE GARRY.... will be interesting to see if the swell will fill in with the storm running away from the land
That's solid, and there's a little bit more of Gary around at the moment after the Xmas break.
" 6-8ft &choppy with a sw wind" every second week pig dog
So Craig, or one of you weather types, what does 2.25m at 17 to 18 sec look like on a well exposed bombie. 2.25m Does not get me to excited but does the 17.5 sec really jack it up. What are we looking at 8 ft? 10 ft? bigger?
Does it also mean less sets?
A lot of varying factors, but with that extra period and if it's coming in from deep water you should see the full potential of the swell, likely 8ft range. Consistency depends on how far your bombie is from the storm. The further, the less consistent.
Could you please add some more information Wbat?
Generally the size of a well exposed Gary depends on the ambient temerature
south coast WA.
Brilliant.
Assuming you're talking about next Wednesday it looks to be about 25 - so there shouldn't be any visible shrinkage but Gary won't quite be in full flight.
Now the other issue is that of perspective - will you be viewing from above or below?
2.5 @ 17s = 12ft on one particular swell magnet in the west .
Theres only one spot that does this while the rest of the coast is smaller .
Needs a specific swell direction for this to happen tho
htp://www.instagram.com/p/Bd8udrxFZkP/
whats the latest?
Hey Craig, I think you Guy's underestimate Swellnet's impact on Surf Tourism. I base all my Travel and surf missions on your forecasts. You should encourage your readers who set off on missions guided by your forecasts to document their Trip. Post on Swellnet. Best Trip Wins.
It's a No Brainer. Bells Pumped over New Year and No One was out. NSW and QLD were flat.
Go Figure That.
'Bells Pumped over New Year and No One was out.'
That's bullshit pal. Car parks (and line ups) were chockers every day by 6am.
Chock full of gits
I'd vouch for that after my paddle on new year's eve at wink and bells
You and every other "weekend surfer" seem to base their surf days on these forecasts. That is why the surf is so crowded on good days and now we are being made to feel guilty by some websites and fork out $8.95/month to read their reports.
At least most surf forecasts are wrong and most massive swells predictions are hoaxes and massively overcalled.
Then again, by hyping everything up as these surf forecasters do, it helps attract more viewers to sell more ad space and then try and influence us to pay for the privilege to read their over-exaggerated waffle.
Learn to read a weather map and boycott them all lol
Eh hem! That's a little hypocritical seeing your here?
This morning at Cape St. Frances should be okay off this storm. https://magicseaweed.com/Cape-St-Francis-Surf-Report/714/
Ahhhhhhh Most of the cars at Bells are tourists "bless their soul" and don't Surf. I call 6 people out at Rincon at 6" uncrowded. I was out there every day. Where were You?
Doesn't matter anyway! I came back to bells last year for the first time in a decade.
And was getting more than my fair share..
Even on the best most crowded days at winki and Bells you can still snag a good solid 20waves if you know what your doing.
The playing field is large and various waves of different sizes at different tides break all over the place at these spots.
It's not always the sets that are best.
The grower at bells is often the one running down the line and holding the best Shape.
And it blows me away that the guys that can't get waves at small Rincon don't just paddle in and get 50 double up shoreys that mostly miss the outside take off and go through unridden. They are sick.
Quota is every thing here you not going to get the barrel of your life but you can get 20 waves and do the turns of your life.
Woof woof quit your barking and stop feeding the sheep, you don’t have to deal with them everyday. It’s not fine for an interstater to shoot their mouth off regardless of how long you lived here prior. It’s just plan all out dumb and inconsiderate
Yes sir! But can I say cloud break looks fucking amazing this week super solid and even offshore.
Have you been there before ruckus..
Do you think would be less crowded this time off the year with a whole week of amazing swell and wind???
Travelled most places quietly and without words following and definitely not on a public forum let alone a whisper down the pub. You may think your words have no ramifications but they do (not that you give a shit anyway). Peace out
Conspiratorial much? What do you think its the 1970s? You think anyone saying 'I had fun at bells' makes a single difference to the crowds, most of whom are kooks these days anyway, when millions of people watch the rip curl pro? People like you are ruining the surfing community in Victoria.
I surfed winkipop about two months ago, it was complete shite with 50 guys in the water and a pretty boring 3 feet of swell. I don't know why you guys get so defensive about it.
Lol mate. A secret spot is a secret spot and I never say a word about these break.
And spots like cat bay and 13th are the words that get spilled out on triple Ms surf forecast everyday with a direction for a spot depending on the wind.
Well done for believing you are saving whole towns from world famous waves by telling people online not to talk about them.
I love surfing and others in the water.
I will spark up a vibrant happy uplifting conversion with as many people in the water and the carpark as I can.
I will call others into waves and never get angery if someone drops in on me rarely even shouting at them as they drop in.
Only time in the last 10years I have been pissed was at winki last year when a guy dropped in on me and we clashed rails 5 times on the wave "his intention" because he thought I had to many waves. Sounds like your thinking.
I love my sport and get more waves than other because I spend hours studying them in photos and will go down after a surf and just enjoy watching everyone surf and learn about breaks.
I broke out of that jealous pigheaded surfer attitude a long time ago and learnt to take smaller insiders or some scraps in between getting a set or two to keep me satisfied at the end of the day.
There is nothing worse than that guy up on the cliff or out in the water that is always negative angry and pissed.
Always blaming someone else because he is a shit surfer and can't admit it so he takes out on Innocent Bystanders or people in the surf.
Ruining their day and making the whole vibe in the water feelore like a funeral than a fun sport! basically that guy can't stand others being better than him. This guy also believes if his day in the water is bad then everyone else's has to be.
Yes I can be annoying online and I have apologized to Ben.
But I have more enthusiasm for other to also enjoy what I have and I will help anyone who asks me and spend time with them if they want to help get them a couple of good ones.
These waves I talk of winki bells beacon are as well know as PIPELINE and no amount of me talking will make any difference on the crowds anymore.
Say what you want and winge all day fucking long because you will not bring my day down or the people around me in the surf you have scared or soured their day.
Because after you have had a bitch at them I will simply say to them how was that fuck wit and give them the next wave...
See you up on the cliff after I have just had a great surf while you just stood up there telling everyone that life sucks and they do to.
And missed out on a great surf because everyone ruined it for you without you even paddling out.
Fuck wit.
Its OK Ben you ban me again now I not really annoyed if you do.
I just not going to be a prick and complain about other people ruining my day I'm the surf because they are having fun.
WW41 I really liked the attitude you have written in & out of the water, don't mind those spots mentioned, ah, but the strategies, haha they are all we have left, shhhh! Being caring,surfing lesser spots, camaraderie, humility, joy, smaller waves and higher counts lol. Just watch me line up those rocks for the further-in takeoff on wave 12 of the session...
Yep I know but I keep my proper game plan for me!
And my mates In the water when they crack the shits because there not getting waves and they want to leave and I don't.
I don't know sometimes you can get a screamer at winki and ride it for 450 meters and not get a turn in.
But then you might get one that breaks for 50meters and do 5 of the best turns you have ever done..
Which is the better wave?
My call, greedy posing fuckwits are the issue in today's surfing
A few of us can think back 20 years to Tony Bullimore's summer swell .
There were definitely some DoUBLE LARRY's that came through on exposed coasts during that swell . WA doesn't look to be blessed with such weather this time . But parts of SA and VIC look good .
https://thewest.com.au/sport/surfing/superbomb-wa-surfers-get-ready-for-...
Good mention in the article there Craig
Quick early size reference form Southside, which seems to have increased from 3-4ft at dawn to 8-10ft now. How's that line of swell!
Watch it live: https://www.swellnet.com/surfcams/margaret-river
More frames from our Margs surfcam:
Pumping!
The top one is a beautiful thing
In contrast, Yalls is hardy picking up anything. It's so small that the half a dozen crew in the lineup are almost sitting behind the tree line!
Craig, is this normal cyclonic activity for Summer? Seems to be more like a winter pattern? And I know this is early but do you have any idea how the fetches will align for Victoria? Looks from that map that most of the energy will push west towards tasmania as it moves south?
No, this storm only really developed due to it being created by the combination of two volatile cyclones moving into the Southern Ocean. Will be good in Vicco but inconsistent winds will be a limiting factor. Keep an eye on my update here.. https://www.swellnet.com/reports/australia/victoria/torquay/forecaster-notes
What kind of open ocean swell numbers are you guys thinking? 3m @ 12 seconds kind of thing?
Just got out of the water at Mainbreak. Pumping!!!! 6 to 8. Long, long lines. Awesome to see the big boards sliding in to a few semi solid ones.
Hooray!
Great to hear!
Oh yeh double L. That Bullimore swell produced some of the best waves I've ever surfed , I remember well. Big Mitch and Kashy owning among many others, don't see that every day hey. Not much down on the deep south today.
https://thewest.com.au/sport/surfing/it-was-unreal-margaret-river-superb...
"Locals have reported swells of up to six metres this morning with breaks Bombies and Boatramps throwing out the biggest waves."
"Swellnet surf forecaster Craig Brokensha has been tracking the surf at Boatramps and Bombie on live cameras since yesterday.
He said the swell was hitting six metres high at 8am, with strong offshore winds providing a haven for experienced surfers.
Many of the 20 surfers seen at Bombie this morning found their smaller boards were no match for the powerful waves and had since returned with bigger boards for a second attempt.
“With this swell in summer there would have been a lot of people who have taken the day off for it but the size and the power of the swell might have put a lot of people off, you can easily get into trouble in it,” Mr Brokensha said."
"Former professional surfer Palmateer suggested reports of six-metre swells were inflated and most waves were no higher than three metres high.
“It’s pretty full on at the moment, it’s definitely six to eight feet but I’d say three metres max,” he said.
“It’s a solid day for swell but we’ve seen bigger.”"
Typo there craig with 6metres ?
Twas under 2.5m according to a trained eye and the Albany buoy supports this .
One of the problems we continually face when approached by mainstream media is how to depict wave heights. In this instance, it appears that there's been some confusion - Craig was only forecasting 8-10ft so it would seem that he's been asked to clarify how high the wave faces were - which equates to around 15-20ft on the face (which they have converted to metres, and used in their story).
Albany 2.25m peak
http://www.srosurf.com/allwabuoy.html
Was a very hyped swell Mr Clam, even little old ladies were talking about this one, epic conditions and high period long lines and waits between the sets, 4-9ft light winds, best day in a fair while , should be reaching you tomorrow, enjoy
Its very promising on the cd buoy stats already , thanks . Tassie not showing yet
Its all about the "Long period groundswell" not the swells Height..
Nowhere will be good on this swell today. Wrong direction completely
There's been a bit of buzz here so far, grapevine frothing it into that 6 range on weekend while I note the forecaster saying 3-4 and the forecast notes thinking magnets will hit 4-5. We will see.
That was two of the best days of swell/surf I have seen in a while. Epic surfing days.
Smashed today, glad it's over. (kind of)
Great to hear! Heard similar things from a few people, stoked.
Boatramp bomber set.
promotional account
Very few like that came through John. I spent most of the morning out there.
Now bombie was a different story ... really firing.
Two autumn like days they were.
Thats right not the left....
Certain swell magnets...
Surfed those reefs when i was younger and we called em west swells...
Good January surf...amazing weather system. . .
Tassie got the biggest buoy reading for the superbomb swell over 3m easy and sustained long period swell . Of all the Australian buoys that is .
All while the storm began near Madagascar from two cyclones joining and heading towards Tasmania.
A great circle path swell sort of thing ?
Clean 18sec was different, before that it had been about 11sec for the previous 2 months .
The barometer has been averaging pretty low for a few months too? perhaps soon an actual big high could enter the picture. The cockle farmers might finally get a low enough tide to satisfy them
I'm sure Gary G will chime in soon about his own Cock le farming techniques . Yeah clam some WA friends of mine didn't believe me this would happen . Truth is a transitioning Tropical system will always see higher wind speeds on the NE leading flank . meaning that most of the time the strongest Swell out of systems like this is usually of W- WNW nature , helped along by its angle of travel during intensification . So yes Great Circle path would come into it . On top of SW WA having a little more shelf in a West direction to deal with that long period . Still i doubt there was many complaints over West .