Cyclone Prospects Warming Up
How many cyclones can you remember forming off Queensland this season? One.. maybe two?
It's been a quiet summer for tropical cyclone activity in the Coral Sea, especially with pre-season forecasts suggesting La Nina would bring a higher than average number of cyclones.
Tropical cyclones typically form during active phases of the Madden-Julian Oscillation (MJO). The MJO is a 'wave' of tropical activity that propagates eastward around the globe. It is simply a large area of low pressure and enhanced rainfall that moves around tropical latitudes on time scales of 30-60 days.
While tropical storms can form at any time during our summer and early autumn, the presence of the MJO moving through the Australian region greatly enhances the chances of tropical cyclone formation due to the increased instability and favourable atmospheric setup it creates. It provides the fundamental starting point for tropical storm formation by way of multiple areas of low pressure.
Combine the MJO with warm sea surface temperatures (as there currently are off north-west Western Australia and northern Queensland) and the likelihood of tropical cyclone formation becomes high.
The MJO 'wave' is currently moving across northern Australia and was last here during the end of January. If you remember TC Iggy which created the rare north-west swell for Western Australia, and then TC Jasmine which formed after a tropical low crossed into the Coral Sea from the Gulf of Carpentaria; these were related to the last time the MJO moved through the Australian region.
Once the MJO moves away to the east across the Pacific Ocean and beyond, tropical activity is usually suppressed across tropical Australia due to the establishment of a more stable weather pattern.
While the MJO increases the likelihood of tropical storms, it also varies in strength. The last two times it passed across Australia (around Christmas and then late January) it was relatively weak. This is one of the main reasons there's been a lower than average occurrence of tropical cyclones this season even though sea surface temperatures have been primed.
The MJO is back again and can be seen clearly on the satellite picture attached (Image 1 above), as a broad area of cloud and enhanced rainfall engulfing the northern half of Australia and surrounds. This time around though it's much stronger and as a result we can expect a flurry of tropical storm activity over the coming week. We have already seen Tropical Cyclone Lua form off north-west Western Australia and it's currently a category 2 system, but forecast to reach category 4 over the coming days.
With the MJO moving through the Coral Sea this weekend and into next week, coupled with high sea surface temperatures, the chance for cyclone formation will become very high and the weather models are indicating this.
A large swell is expected for the Australian East Coast during next week and this late season burst of tropical activity is all linked to the MJO. To forecast when the MJO is expected to come around and when there's an increased likely hood of cyclone activity you can use Images 2 & 3.
Image 2 (above) shows the current position of the MJO and it's track and strength over the last forty days, with Australia being positioned on the right hand side of the diagram (section 5) and the MJO travelling anti-clockwise.
What you can see is that during February the MJO was on the other side of the world and strongest in section 7 which is around Central America, with it re-intensifying as it crossed through the Indian Ocean during the start of this month. Image 3 (right) can be used to forecast the MJO 2 weeks ahead and currently indicates that it will weaken after passing across us and then restrengthen in the Western Pacific Ocean.
The MJO is likely to come around through our region again during the middle of April but as the seasons change it moves further north and will likely play no significant role until next summer.
But keep an eye on the East Coast forecasts over the next few updates as large swell event is highly likely with the last burst of the MJO moving through our region for the summer surf season.
1) The Madden-Julian Oscillation is an eastward tracking 'wave' of tropical instability around the globe with a period of 30-60 days.
2) The current MJO phase may help facilitate the formation of a tropical cyclone in the Coral Sea in the coming week
3) Once the MJO passes the likelihood of further tropical acitivty is suppressed until it comes around again.
The current position and track of the MJO for the last 40 days can be seen here: MJO Phase The forecast strength and track of the MJO next 14 days can be seen here: MJO Phase Forecast
*rubs hands together*
Looks like the family trip to Angourie is going to be swamped with sweet sweet juice...
Careful what you wish for ........floods, onshores and bank-busting storm-surf is also on the menu.
its also in sync with the monsoon trough so it should be a ripper.
Latest model updates are in stark contrast to each other.
GFS would indicate an oversized sand gouging, property damaging and erosive tropical low right off the SE Qld coast as Steve was indicating while EC has a tropical low intensifying over near New Zealand, with a weaker system up near the Gulf of Carpenteria.
Things are likely to chop and change for at least the next couple of days making it very tricky to forecast!
There's been some of the greatest model flip flops ever in the last 48hrs.
Truly astounding, and impossible to remember which model said what, 'cause they've been contorting so much.
Hope EC comes off.
Don't want a bank-buster at the start of Autumn.
Hope everyone gets rocked! In a good way.
Natures natural phenomenas are so much more fun than world news!!! Surf/swell/good waves ridden and recorded.
Disastrous erosion? Not so much.
Ah, such is the unpredictability of the active monsoonal season.
The banks may cop a hiding but it'll take a bit to upset the reefs.
Lets just hope the winds co-operate and stay calm.
BTW, good write up and explination of the subtleties Craig.
Good write up - even though MJO's and stuff like that indirectly relate to my employment I still had no idea how to read that circular worm graph on the BOM, cheers for that.
You guys over there keep praying - Luahahaha ;-)
Good luck to the people posting forecasts today (Ben? Steve?). Still seems like horrid inconsistencies in the charts. Got any other methods at your disposal.
Craig, very good mate, as usual I learnt something new.
I did see that band of cloud covering the entire top third of oz last night, and thought it to be significant. This article explains the background phenomenon.
@ the spleen, sure there are inconsistencies in the models, but on the other hand they point to the same thing. Those forecasts should be looked at as the 'highest probability' outcomes rather than forecasts.
While it makes specific locations of cyclone development highly subjective, the likelihood of a cyclone or very intense low in our swell region very high. Forecasting swell for next week, very high chance, picking the spot, very low.
Then Craig just writes his forecasts like an astrology chart - "you will run into a complete stranger today who looks at you in a funny way. You may or may not react emotionally to this encounter."
This is exactly why Swellnet is my favourite website.
Can I ask a question Craig?
So the MJO is the name given to this moving mass of low pressure, which gives birth to all these baby cyclones along the way. How long has this one mass been around for? Years? Decades?
All these years I've worshipped these cyclones. Vania, Jasper & Betty being the better ones I've personally made the pilgrimage to the points for. But perhaps all along it's been the MJO I should be getting excited about.
Clear the schedule boys...
The MJO was only discovered in the early 1970's but it's part of the climatic cycle and is a permanent feature that has always been present.
The MJO provides the enhanced environment for these cyclones to form but whether the cyclone produces any meaningful swell is up to the individual storm.
The link between cyclone formation and quality long-lived swells is another story for another day with many a discussion actually steering away from this. It's actually the tropical storms that make an extra-tropical transition that seem to offer the better quality swells.
I agree with Steve. I hope EC comes to fruition. GFS will just be a mess for SE Qld. I do note that GFS is the major outlier at the moment in the models, with it still running for a tropical low off SE Qld.
GFS and EC are computer model forecasts, Mitch.
GFS data is courtesy the USA's federal weather forecasting agency (NOAA), while EC data is courtesy an intergovernmental organisation in Europe (European Centre for Medium-Range Weather Forecasts).
There are probably another dozen weather models around the world, but GFS and EC are two of the most reliable.
The main difference between them are the algorithms that they each use to 'predict' the state of the atmosphere up to a couple of weeks in advance - some are better than others (the BOM's own model was decommissioned a few years back, mainly because it wasn't particularly accurate - they've now launched a new model in collaboration with the UK Met Office, which is much better).
So many questions, but I mainly just wanna know who GFS and EC are (weather forecasting services I presume)??????
Also Shoredump, I don't think that the MJO can be thought of as a 'mass', that implies the same air mass just keeps going around the globe forever. I think several different air masses can be intensified at the one time by the MJO 'wave', which kind of just doesn't show up over the Atlantic. But I haven't studied meteorology as much as some these guys so I could be wrong.
Ha, added then deleted a comment. Now Thermalben looks like a magician!
So my next question is: don't NOAA's MJO and GFS models contradict each other. If the MJO forecast is for weak activity here and stronger activity further east, why does their synoptic chart model predict an intense ECL and not a low near the North Island like the BoM is???
The MJO is not a model, it is a weather phenomena and it is slowly moving across the north of the country.
The charts I linked to above show where it's been the last 2 months and also where it is expected to head and intensify over the next 2 weeks.
When it is in our region it usually takes a week or two to pass by and during this period the weather models EC and GFS will struggle to pick up and forecast the tropical developments and will disagree a few days out.
So the current disagreement between the models is just because they struggle with tropical developments most the time, although with this swell event they are both performing worse than normal.
Oh and also the weather model forecasting the MJO is totally different and focusses on different atmospheric characteristics compared to the GFS model forecast.
I was 600 miles off Darwin at sea 3 weeks ago and you could actually see the change in weather as the MJO intensified. The ocean had been mirror glass for a fortnight and then it started stirring, the currents picked up from the west and the patchy afternoon thunderstorms started to form into proper line squalls.
I'll be on a road trip to the North coast next week, if our new friend MJO can whip up a low far enough away not to ruin the sand but just right to send a juicy groundswell that would be great.
Craig, can you put in an order with Huey , cheers :)
Hmmm ok, I assumed that they would use the results of their global forecast model to make the MJO forecast. I guess it doesn't make sense to assume that because both situations, low off SEQ or low over the North Island aren't in tropical latitudes anyway.
I would like to follow the MJO around . dont go if no MJO .lol
The first active phase for the season of the Madden Julian Oscillation is currently moving across the Australian region and this is the cause of the 'troughiness' showing on the weather charts for next week in the Coral and Tasman Sea's.
It's a weak signal and won't amount to any Tropical Cyclone formation (due to the waters not being close to warm enough), but it's the first real 'troughy' weather pattern we've seen since autumn and should produce some fun waves across the East Coast (especially the Goldy who've missed out of late) later next week.
The East Coast is about to enter into a classic E'ly trade-swell tending groundswell episode that's expected to be quite prolonged, extending from Monday next week through to the following weekend.
Keep an eye on the site tomorrow for a more detailed analysis and break down of the swell event.
Looking forward to it cheers
Craig, the big question though is, will it be EC or GFS? EC (with the tropical low swinging down in the Coral Sea) will more than likely be a bank busting affair, where as GFS, with the tropical low pushing down in the South Pacific looks to be a much much better swell with respect to non-bank busting.
I'm praying for GFS as I've found myself some sweet sweet banks of late and don't want them ruined back to a storm bar affair!!!
Hard to say at this stage Don, but I'm hoping for GFS as well or maybe a hybrid so that we get a good amount of swell down here as well instead of the system possibly slipping behind the North Island.
Hello Ossie and Gazza!!!
Tropical Cyclone Oswald? Stay where you are, don't head for the hills, no-one's getting hurt by a cyclone called Oswald.
Where's Gazza? Fiji?
And yeah, won't see any real swell from Gazza, but certainly damn good to see such an active monsoon trough stretching across the top of the continent and out into the Tropical South Pacific.
Also, if GFS has it's way, we won't see anything from Ossie either. It's the post Ossie tropical low that spins off the monsoon trough that delivers our swell according to GFS.
The models are still a bit undecided on all this up and coming activity so we'll hold off a couple of days regarding the article sorry Mitch.
I tell ya though that the lastest 18z GFS update has ex-Tropical Cyclone Oswald reintensifying as an extra-tropical low off the SE Qld /Northern NSW coasts through early next week in conjunction with the low above New Zealand.
Active times ahead!
Heres hoping that pressure gradient comes to fruition, it'll be game on in my area this coming weekend. Haven't seen anything like that for quite a few years now.
As always though, these lows are mighty unpredictable.
"I tell ya though that the lastest 18z GFS update has ex-Tropical Cyclone Oswald reintensifying as an extra-tropical low off the SE Qld /Northern NSW coasts through early next week in conjunction with the low above New Zealand."
And EC and ACCESS G have been progging this for a while in their long term runs also.
WE DO NOT WANT THIS!!!!! Piss off inland Ossie!!!
And for tonights change of events ... Some models Access R ? ?? . has Oz as a Tropical storm all the way to Mackay for Five days then finally out into the Corla Sea ( and then intensifying ) to a swell producing ( mainly for those north of the Tweed ) state out near New Caledonia .
This is turning out to be quite a dynamic period. 18z GFS has come into alignment with 12z ECMWF in that ex-TC Oswald will drift south down the North Coast will intensifying and then turn into a serious system off the Sydney coast!
Hopefully by tonight's 00z run they fall into proper alignment!
ok Craig, Stu and Ben
if this system falls into place,
can you please just list (from North to South) all possible locations that will be firing.
thanks in advance
Should be all time at Batau Bay and Blue Bay
G'day Craig. Something that isn't quite clear in the extended report & forecast: What will happen with the trade swell between now and Monday, regardless of Ex-TC Oswald? Linear build in height and period to Monday's forecast?
Hi Mitch, yeah the trade-swell should just muscle up slowly through Friday but more steadily through Saturday but then rise steadily through Sunday, reaching 3-5ft through the afternoon and holding through to at least Thursday. This would be the case without Oswald, but jeez it's gonna get a lot bigger looking at the current model guidance with him in the mix!
Righto Ossie, you can just feck right off now!!!! We don't need you down here and don't fecking want you so go east young man!!!!
Screw your sandbanks Don! Here's hoping for an XXL NE swell and southerly wind combo for southern NSW, might even be enough for me to sweep the dust off the bodyboard and get out there. And a lot of rain wouldn't go astray either, most of nsw is either in drought or heading that way.
Cheers Craig, just managing expectations!
I agree with Scoopie. Bar the banks! Even if you live on the Goldy, it's a long weekend, so sniff out some other sea floor surfaces for a change!
are you guys sure about this swell....??
still learning about the east coast swells......but looks like the low actually ends up on the gold/northern Coast.....looks supa wet????
Very sure Brutus, keep an eye out on an article on the up and coming event around lunch time.
Ex-TC Oswald is gonna move down the entire East Coast bringing torrential rains and large onshore swells, but once the wind swings offshore and rain clears we should see some great waves!
"Ex-TC Oswald is gonna move down the entire East Coast bringing torrential rains and large onshore swells, but once the wind swings offshore and rain clears we should see some great waves!"
Great swell, yes, but not sure about great waves Craig as ex Ossie will destroy what sand has returned over the last few months, hence I can't see there being any real quality waves in SE Qld post Ossie's drift south of us and when that longer period E'ly groundswell arrives post long weekend.
Yes totally agree, Don, it all depends where Ossie drifts offshore and at this stage the best region to aim for is the Southern NSW Coast. Further north it looks like winds from the northerly quadrant will spoil most of this swell :(
Just as a side note, let's see how ACCESS G goes.
24th morn run: Ex-TC Ossie has tracked down the coast to just nth of Fraser at 991hPa by Monday the 28th. Then on the 29th begins to weaken and drift NE. E to NElys maintained across the Sthn Coral Sea, against a Tasman/NZ high.
On Tuesday 29th night, a low squishes against the high, just NNE of NZ, to a min of 992hPa. There is quite a long belt of trades, beginning to aim a pulse of at least 6m at 14s (AUSWAVE G) towards us...
The viewer isn't able to display a decent primary swell on the East Coast until Sunday. But combined sea and swell gives >2m sth of Fraser from Friday onwards.
Lastly, winds at 500hPa seem to be supportive of both systems (can see two circles going round). Winds at 200 aren't for Ossie but are for the other.
Also showing a low coming in from way out in the Coral Sea to move west and join along the same trough line.
Craig has just posted an article about the coming mix of swells: http://www.swellnet.com.au/news/3394-cyclone-oswald-spikes-tropical-punch
The next active phase of the MJO is forecast to move in from the west and enter the Australian region in approximately a week.
With this we can expect an increase in tropical activity and possibly a Tropical Cyclone or two, and while it doesn't look to be as strong as the last passing, some of the long-range forecast models are already picking up some funky developments both east and west of the country into the middle of next week.
Ooohh. Just in time for Snapper, huh?
Too bad about that big hole out the back.
Yeah I'm not sure what they'll do there. Rainbow to greenmount is pretty good. Everyone is saying there's no sand to pump into the snapper hole.
Is it true they can no longer relocate the contest?
great sand at burleigh ........relocate it.
Oh, wouldn't the Harris brothers and co. just love that! Word is Letitia Spit has no surplus so the only sand to be pumped into Snapper is the naturally migrating sand. Also, they pumped about 40,000 cubic metres in January only to lose most of it in ex-TC Oswald.
Oswald was an angry man.
Those forecasts look to have it stalling somewhat over the Maritime Continent? Albeit weakening at the same time??
I think most forecasts have it weakening but continuing to slowly track east into the Pacific Ocean. Here's an article about the upcoming active phase I wrote today: http://www.swellnet.com.au/news/3429-last-chance-for-a-tropical-blast
Wish I checked the date on the above article after following the link from todays forecast notes. Would have saved me scratching my head for ten minutes. Good knowledge though.
Haha, that would of been a total trip reading that thinking it was current. Yes, I should probably make a new article just solely explaining the MJO.
That'd be great Craig. Coming from the N Hemisphere where everything spins the other way means I'm re-learning all about forecasting down here, but you and this site are a huge help. Thank you.
Im heading to the gold coast on the 18th of January to the 25, have you got a rough idea on the swell forecast?
If you're a Swellnet Pro subscriber, you'll start to see forecasts for Jan 18th appear in a few days time.
What is the latest status of the mjo and la nina?
There has been some extreme weather around the country.
The La nina affects here is it ?
Not quite, that's just due to the MJO.
La Nina mostly influences the East Coast as it's related to a build up of warm waters in the Western Pacific and Coral Seas. It's influence on WA and SA is very minimal if at all.
Any info on models predicting severe tropical cyclone for late jan/early feb for coral sea? Just read on internet somewhere and cant find it..
You can check the MJO forecasts here.. http://gpvjma.ccs.hpcc.jp/TIGGE/tigge_MJO.html
Just spent 10 minutes staring at the squiggles, back to the article, I think it means that most met offices (BOM being very circumspect) see the MJO strengthening in the next 4 days through Indian ocean region, then weakening a bit around 8 days on into the 'maritime continent'. So no cyclones. ??
That was 3 days ago, looks to have peaked across the western Indian Ocean and will move east still with strength over our region.
If it holds its strength we'll definitely see cyclones, but we need it to push further east otherwise they will be up around the north of the country and not the Coral Sea. We watch and wait.
At least there is activity inbound, give me a tropical low on top a stationary high please!