Winter: La Nina refuses to leave the building.

[steve shearer]

And this upcoming ECL/Hybrid low looks like a double whammy bank buster supreme, with the chance of some ten foot plus surf if it tracks away adagio

[AZ]

La Nina is well and truly done based on all indicators, so I don't understand this title. East Coast Lows are most frequent in June, so no surprises with the past week and the forecast charts for the week to come.

[steve shearer]

Might be well and truly done in terms of atmos/oceanic indicators but in terms of on the ground weather it is very much still in evidence.

And rainfall percentiles for the autumn/winter predictability barrier will prove that in hindsight.

Frequency of ECL's is also closely associated with ENSO cycle. 2007 being exhibit A. Also 1967.

[AZ]

I see your point. There are still warm anomalies through the Coral Sea which may be something that persists post La Nina events and enhances low development/rainfall. http://www.weatherzone.com.au/climate/i ... jsp?c=ssta

However, looking at the eastern equatorial Pacific things are swinging towards El Nino in terms of SST anomalies, that's why I questioned the title. Back to watching the webcast, pretty solid...

[steve shearer]

The North Coast of NSW is extremely sensitive as an indicator of ENSO cycle changes, particularly lingering or early onset La Nina's or the approach of transition phases which are only detected later by hindcasting.
Most probably due to it's position on the cusp of tropical and sub-tropical/temperate atmospheric/oceanic influences.

[Donweather]

Geezus Alex....where the hell you been mate? Long time no hear.

[Nick Carroll]

Just 'cause there's an ECL off northern NSW/Qld in early June doesn't mean La Nina's got anything to do wif it.

They happen in off years, on years, whatever.

[steve shearer]

>><<

..smacks head.....


I'm talking about a bigger suite of factors of which the presence of two back to back ECL/ hybrid low systems is one symptom of a larger whole.

Lets look at recent history in a little more detail, some other time.

But there's been an interesting meso scale pattern occurring as we seem to cycle into a more active Nina dominated base state.

[Donweather]

Here she goes!!!

http://www.derm.qld.gov.au/environmenta ... &paramid=1

[oldman]

While acknowledging the far superior training in meteorology of the contributors, I can't remember an ECL forming off the qld coast, summer style, in mid June.

East Coast Lows are most frequent in June, so no surprises with the past week and the forecast charts for the week to come.

Which led me to be very surprised by this comment from AZ.

I would have thought an ECL forming up off the qld coast almost never happens in June but is a late summer, early autumn phenomenon.

As opposed to the great and scary ECLs that tend to form off the NSW Sydney to Eden region and south, which I would guess to be quite a different phenomenon, although in physical terms the same thing.

And I would have guessed at July and August being greater ECL producers as well, given that June is so often flat and witless on the east coast.

Go on, tear me a new one.

[steve shearer]

The question is: what happens now?

My guess/hunch is that the one-two punch from the Tasman then Coral Sea complex low/ECL's represents the last great explosion of a fading Nina. In effect the rebalancing and atmospheric release of all that built up energy that Nina's store in the West Pacific warm pool and, via the East Australian Current, the Tasman sea.

That would mean in terms of base state a return to a mild winter pattern typical of neutral or weak Nino. Westerlies, stable atmos dominated by sub-tropical high pressure and small/medium S swells from fronts in the Tasman. The Southern Annular Mode has been in negative territory too, which suggests further cold front activity through the last days of June. It is now progged to go weakly positive which barring further ECL development would suggest a pretty flaccid start to July.

Thats Fine. The best thing for sandbank restoration around here is a pattern of weak/moderate South swell activity, just to get those storm bars gently moving shoreward and and northwards.

Moving into a weak Nino or neutral with a base state of negative PDO and IOD would suggest a pretty mild winter with a late kick into Spring, before a dry northerly pattern.

Supporting evidence comes from early activity from the young male Eastern Rosellas who are looking for mates, and this correlates with mild winter condys and an early Spring.

[Grooter]

I don't understand most of that shit you blokes are talking about.

But it has been much more cold and wet than usual down south.

And to top it off I got rocked gently on my couch last night by an earthquake!

[alakaboo]

Moving into a weak Nino or neutral with a base state of negative PDO and IOD would suggest a pretty mild winter with a late kick into Spring, before a dry northerly pattern.

Supporting evidence comes from early activity from the young male Eastern Rosellas who are looking for mates, and this correlates with mild winter condys and an early Spring.

So which is it, late Spring or early Spring?

Are the storm bars that bad down near you, Steve?
I haven't checked out everywhere, but where I have been wasn't as badly affected as I expected. Sand was shifted out of the dunes, sure, but didn't seem to go all that far offshore.

[steve shearer]

I meant a quiet winter with a late kick Aug, and into Spring pattern proper by Sept.

We've had winters where S swells have been strong right through late Sep.

This is all hunch though Boo.

We'll see what happens.

[alakaboo]

My hunch basically matches up with yours.
I don't keep records or memories like you, but last time I can remember this sort of pattern (about 2000-2001?) we had a dry mild winter, and great run of medium size surf late July-August.

[brendo]

steve, i believe the enso is showing nuteral atm. which would explain some good early season snow, and a big dump coming. base could be 1m by july. if it stays that way, could be epic snow yr. last yr started like this, but mid july soi shot up over 10. and it stopped snowing.

[Donweather]

That would mean in terms of base state a return to a mild winter pattern typical of neutral or weak Nino. Westerlies, stable atmos dominated by sub-tropical high pressure and small/medium S swells from fronts in the Tasman. The Southern Annular Mode has been in negative territory too, which suggests further cold front activity through the last days of June. It is now progged to go weakly positive which barring further ECL development would suggest a pretty flaccid start to July.

Still running with this scenario Steve?

[steve shearer]

I reserve the right to be totally wrong and defer to the title of the thread.