El ninyaknow

you still manage to find time for this even between forecasts! :-P

Klaus and Wolter developed a fairly robust MEI index using reconstructed analysis data characterizing ENSO behaviour since 1871. This MEI index this will take you back all the way. Other, possibly more suspect literature attempts to go back the 1600's to look at solar cycle impacts/relationship on/to ENSO but its not reliable, note the MEI index possibly over does the 1877/78 event surpassing the 1997/98, but I guess we will never truly know! Good luck with your research - you may want to investigate how the different ENSO classification "flavours" of warm events affects your results. http://www.esrl.noaa.gov/psd/enso/mei.ext/table.ext.html. I think the authors mentioned have written a paper (2013) perhaps which list these events since 1871 in order of their magnitude which may help you also.

It will certainly help to focus the convective maximum towards the central Pacific, and hence a CP signal upper air pattern highlighted this week by VP 200 anomalies (Twitter post my Mike ventrice- not sure how to post photos on my phone) . Whether or not the most recent KW which was impressive in terms of its magnitude and longevity will have a slight decelerating effect on the cooling of late in the Nino 1.2 region remains to be seen. The eastward extension of the EA jet is another growing demonstration of the attractive forcing of warm SST anomalies becoming increasingly confined to the central Pacific after such a basin wide display. Interesting thought that the anomalous La Niña esque warmth of the Indian Ocean trying to provide a competing convective pool is somehwhat muting the El Niño signal seen both in the SOI and AMM but hopefully with another bout of MJO attraction to the maritime continent and beyond, should help cement some favourable late winter impacts downstream not to mention anything going on waaay above our heads!! :-P

Nice kick in the Nino 3 and 3.4 regions in response to latest KW, also a little deepening of the thermocline in the WPAC, should keep this quite remarkable event going a little longer and perhaps strengthen the late season CP signal which has been trying to emerge between successive WWBs that just keep on coming!! Using tropical SST analogues is becoming increasingly difficult if not impossible this year!! Looking for that cheeky wave number 5 pattern to emerge across the Pacific and keep the Azores high imprisioned in the Azores well into spring :-)

It depends on the type of SSW, since 1958 (reasonable upper air records) a split vortex event results on average with the 40 day period after the central point (10hpa winds at 60•N reversal) in a 3k departure from average temperature across Eurasia (focuses on the NW) from a sample of 15/20 depending upon criteria for SSW split deferentiation, often lead by K2 wave energy focused solely over the Pacific side (not yet modelled..) whereas a displacement event lead also by k2 wave breaking but focuses equally on the Siberian and Pacific side often leads to near neutral temp anomalies in the 40 days after the event but 1-2k lower anomalies for the USA (east focus). In past years with cold anomalies the best bet is to look at anomalous tropical Pacific forcing.. One thing is for sure we are certainly moving into uncharted territory this year in both the Pacific and the strat...unfolding)... All eyes to the ECM!!

I did a little post of the ENSO discussion thread re the decline or lack of forcing over the next month 6 weeks which ties in well with your thoughts..I hope :-)

Physical model forecasts too progressive with removal of heat from the Pacific basin due to under expectation of next downwelling KW about mid month which will slow the heat removal or perhaps even add some heat for a time towards the months end before a slower more seasonal decline of heat through Feb. This extra heat retention may prove useful for sustaining a meridional component to atmospheric waves late in the season which may entice any Azores High formation towards the NW rather than trying to move back towards its climatological position and flatten any -NAO signal and spoil the party come late Feb. Another little "nice adjustment" due to slightly more amplification/longevity of the MJO towards the dateline, something of which the models are JUST about getting to grips with, expect more uncertainty with the upstream picture. Perhaps another little contribution from tropics for delivering and prolonging cold down the line, although help from above maybe required and TBH its about bloody time! :-P

Also of note is the model tendency to quickly break down amplitude of MJO events when in reality they may hang around a little stronger or longer, this may give us the window to promote Cross polar WAA and hit the PV twice maybe 3 times during January! Models not yet seeing this in relation to a possible retrogression of the developing Scandinavia high but there is time. Even with a QBOw, which actually is nearer neutral at 30mb, we might flip into a -NAO by early Feb... Old Cohen seems pretty keen on heights rising across the Pacific suggesting possible W2 pattern and subsequent vortex split environment...but we all know which side of the fence he lies... Either way possibly more exciting than was initially expected during such a strong EP ENSO event, speaking of which with convective maximums shifting westwards could take on more of a CP winter back with the implications of that as we are well aware of :-) happy new year mate :-) 2016 lets go! #frozenfeb

Actually era20 re-analysis data using the SODA ocean suite can replicate ENSO behaviour back to 1870. Although the 1877/88 EP event is often too strong.

New to this game, but I thought I would add a little if I can. Most recent down welling (warming phase) of a kelvin wave started ~at the dateline at the end of October on a similar trajectory as K1 and K2 with roughly a 3-4 week lag time lag time between warming the Nino 4 region and affecting the 1+2 region. This has been witnessed 4 times in 2015, notably two successive times in jun and July not allowing any upwelling cooling phase to intervene producing a net warming effect upon Nino 3.4 region. Currently the Nino 4 and 3.4 regions are at 1.8 and 3.1 degrees above average respectively and will probably not be able to rise any further. Expect the Nino 4 region to decrease relatively quickly towards the months end. However the 1+2 region has not yet experienced the warming from the KW, expected probably this week or the the next. The last KW pushed the 1+2 temps 0.6 degrees in a week, so expect a similar kick if not more...possibly up to 2.6 or 2.7 this time as the waters cool climatologically. Although the Nino 3 region is nowhere near how warm it was in Nov/Dec 1997, this truly basin wide event will be historic and has already broken atmospheric indices relating to upper level wind anomalies documented by some research over the pond. Closer to home the amplified wave pattern which should continue as the heat anomaly strengthens in the east Pacific. This should continue to provide some opportunities for some north or NE air outbreaks, but will only be transient. It has been said that these amplified or excited rossby waves can increase the likelyhood of strat vortex interference but there are many other drivers which may inhibit this, this winter. If surface advection feedbacks start to emerge in the new year across the West Pacific, a Modoki signature may emerge which may have some implications for the winter back to which some here may re-ignite some interest after what will be a predominantly wet and windy start to winter. I will try and post some graphics to add to this once I work out how to do it on my phone...?! Cheers.