The Snow Lovers Appreciation Society Winter 2014/15 #MOD NOTE #1

carltonleon wrote: »

http://www.irishexaminer.com/ireland/white-christmas-for-irelands-south-says-nz-forecaster-251254.html

Ken Ring's Winter Prediction .....
Right everyone down to Kerry for Feb 17th - 19th .... Anyone have a spare 4x 4. :)

That was last years prediction and probably couldn't have been more wrong!!!

omicron wrote: »

That was last years prediction and probably couldn't have been more wrong!!!

The papers do it every year anyway. This year, I have noticed a fair bit more berries on the bushes compared to last year. Definitely will be a sign of something although I'm not expecting anything like what we had in 2009/2010

This the weather or motor forum?

Morning folks. Anyone looking for an early start to winter is in a good spot right now in to next week. We should see frost return along with some cold nights especially inland.



It's only the middle of October so nothing to get carried away with but i'm fairly content with the trend right now. Watch for some very cold air going in to Scandinavia from the pole next week.

I would not rule out this effecting us in some form at some stage if the synoptic set up goes our way though the chance of that happening is not high. Too many variables this far out.

Still an early introduction to winter next week could well happen which would be a fairly dramatic reversal of fortunes given the September we had.

maquiladora wrote: »

This is quite an interesting thread.

https://forum.netweather.tv/topic/81494-october-pattern-index-opi-monitoring-winter-season-2014-2015/

That was a fantastic read. Pretty much has started me model watching now for Winter 2014/2015 season

And so it begins...

Thatst last years forecast, which couldn't have been more wrong...

Billcarson wrote: »

The index for today is at -3.91,if it carries on this way we could have a very negative index by the end of the month.
http://app.til.it/opi/

You have to wait until you get near the end of the month to see what the OPI will be though. We are only 10 days into the month, it's using the GFS forecast for the next 10 days to estimate the rest, but those estimates can be way off.

It will be interesting to see how it looks in a couple of weeks.

It'll be snowy this winter, if only to vex me.

maquiladora wrote: »

It will be interesting to see how it looks in a couple of weeks.

I don't know much about this October index thing, but from what I have read, there seems a lot of focus on high correlations, with very little talk on actual causation. Do you know how this index is calculated? as there is very little info on his site. Wouldn't mind messing around with some stats to see if indeed there is water to be held.

Kermit.de.frog wrote: »

Morning folks. Anyone looking for an early start to winter is in a good spot right now in to next week. We should see frost return along with some cold nights especially inland.



It's only the middle of October so nothing to get carried away with but i'm fairly content with the trend right now. Watch for some very cold air going in to Scandinavia from the pole next week.

I would not rule out this effecting us in some form at some stage if the synoptic set up goes our way though the chance of that happening is not high. Too many variables this far out.

Still an early introduction to winter next week could well happen which would be a fairly dramatic reversal of fortunes given the September we had.

That particular chart shows a similar pattern over the N Atlantic/Euorpe region to the same period last year.

maquiladora wrote: »

Most of the documentation seems to be in Italian. I'm not really sure what the proposed causation is exactly, its the high correlation that interested me to be honest. :P I don't buy into most long range stuff but there does seem to be something going on here.

I found this. How's your Italian? http://www.meteogiuliacci.it/articoli/october-pattern-index-opi-un-nuovo-indice-altamente-predittivo-per-la-stagione-invernale.html

Here Maquiladora, fortunately my internet skills are better than my understanding of the weather! This is the translation of that page:

We publish an interesting research study on a new index teleconnettivo that would prove to be highly predictive for the winter season, led by engineers Riccardo Valente and Alessandro Pizzuti and astrophysicist Andrea Zamponi Center Weather Tuscany. In our view, the proposed index has the unquestionable merit of sum up the potential predictors winter, not always consistent, the indices used so far in order ...

Currently the most used part of the seasonal forecast is based on the functioning of global climate models (GCM). These, in their calculation processes, mainly consider the variability of the ENSO cycle. However, for regions far from the tropics (with particular reference to the north-eastern USA and Europe), the reliability of ENSO predictor is uncertain and therefore still limited. By virtue of the lack of predictability of climate over the extratropical ENSO signal, were considered other ways to improve the predictive capability of the GCM (seasonal forecasts) in reference to the extratropical latitudes.

In this regard, within the boreal winter, the Arctic Oscillation ( AO ) pattern is the most important because it can directly influence the climate in many areas, even thousands of miles away from home arctic, and which are the main centers of population in the Western world (Europe and North America). For example, in reference to central and western Europe, the AO shows a high correlation with the calculated geopotential anomalies on the winter quarter (about 0.86). As has been said, a forecast of the AO winter constitutes the most reliable way to get a reliable information about the performance of the winter on those areas with several months in advance. In this research we present a new index highly correlated with the winter AO and therefore can be used in the prediction of the winter season in junior high northern latitudes.

The idea of ​​developing the new index comes from careful observation of the index today more predictive for the winter season is the index SAI developed by Cohen in 2011.In particular Cohen in the latter study showed that, to be correlated with the winter AO is not the level of snow that is reached at the end of October on the Eurasian sector, but the rate of increase in snow cover below the 60th parallel on the same field. In other words, for the same final extension of snow cover ottobrina, you may have implications also very different depending on the "timing" of innevamentoe depending on the spatial distribution of snow same (mainly if above or below the 60 ° parallel ). All these factors imply that the causal factor (ie the factor that determine the interannual variability of the AO) is not the Eurasian snow cover, but the dominant circulation pattern that occurs in the month of October, which is the cause of ' snowmaking same (and therefore of its quality in terms of both speed of advance that positioning) .It of facts in this regard has been possible to verify, already in the preliminary phase, a remarkable correspondence between the circulatory dominant pattern that is established in the month of October and found that on average in the winter quarter following (see the attached search and free download). The study has therefore been addressed in the formulation of an index numeric able to synthesize the circulatory pattern of October. This was then validated by checking the rate of correlation with the AO winter average on the next winter quarter, in consideration of a sample of very extensive years (range 1976-2012). By virtue of its meaning, the new index has been baptized with the name of "October Pattern Index" (OPI).

For explanations concerning the theoretical formulation and numerical index and for the presentation of the calculation model implemented on the software "Telemappa Next Generation", please refer again to search. The results on the correlation are shown in Fig. 1, which shows the historical trend dell'October Pattern Index (OPI in burgundy) and the Arctic Oscillation in the winter quarter from December to February (DJF AO in black), for the sample years 1976-2012. Coefficient r correlation for the two series is equal to 0.91.

From this we see that the rate of correlation between the OPI, calculated to October, and the AO average for the three months next winter, it is exceptionally high and equal to 0.91. Even "as you zoom" on the last years (from 2000 onwards) can be seen as having had this tool before, it was always possible to predict with great accuracy the performance of the AO pattern winter with 4 months in advance, as be observed in Fig. 2 illustrates that the 'historical trend dell'October Pattern Index (OPI in burgundy) and the Arctic Oscillation in the winter quarter from December to February (DJF AO in black), for the sample years 2000-2012. Correlation coefficient r for the two series is equal to 0.97.

As previously mentioned, the ability to predict the AO winter is considered the most important advance in the realization of seasonal forecast winter. The Arctic Oscillation (AO), in fact, represents the state of the atmospheric circulation over the Arctic and therefore constitutes the dominant mode of variability in boreal winter extratropical regions. In addition, the implications induced by the signal of the Arctic Oscillation, are more tangible in its reference to Europe and the eastern United States. Therefore, a correspondence so high (almost perfect) between the trend of the Arctic Oscillation (AO) and the index (OPI which is calculated with 4 months in advance), results in a further improvement of the predictive capabilities to seasonal level for extratropical boreal regions, with particular reference to Europe and the eastern United States. Just about west-central Europe, it was possible validate, even numerically, the predictive ability of OPI, referring to the parameter of the fault geopotential average calculated on the winter quarter, in reference to the same sample of years included in 'interval 1976-2012. The results of this analysis show the existence of a correlation decidedly high and 83% (highly significant correlations are found even in reference to the individual states the central-western Europe, from the maximum value encountered for France, r = 0.82, and the minimum on the north-eastern Spain, r = 0.70).

Furthermore, the OPI, since it constitutes a numerical synthesis of the pattern ottobrino dominant (which as mentioned shows a remarkable affinity with the patterns of the main circulatory following winter season), is able to provide, unlike the majority of predictors, also of information about the type schema hemispheric circulation, allowing the operator to perform considerations also on the "quality" of any "actions meridians" of the Polar Vortex winter.

In conclusion, our work represents a further important step forward in terms of its predictive capabilities of the winter season, as we present a new index from the best predictive capabilities. The OPI ("October Pattern Index") is able to explain, with four months in advance, more than 90% of the variability of the oscillation Arctic winter (winter-AO) and, therefore, is proposed as the index more predictive ever, especially in reference to Europe and The United States Oriental countries for which the consequences induced by the signal of the Arctic Oscillation are more tangible, and for which even the most sophisticated GCM, show, on seasonal time scale, levels of reliability practically insignificant.

We wait for you in early November to see what could be the first screening of the upcoming winter season, according to this index.

emmetlego wrote: »

Sorry, but those look streets apart to me. I've a brother who is educating me on his profession, and he works for the UK met office. So I kind of have an idea what I'm looking at.

Johngoose wrote: »

No, over 80 million euro of the stuff confiscated recently off the Irish coast.

The Met Eireann app on my phone at 5.45 this morning said we got a SNOW shower in meath, i know we didnt, as i started the car for the wife before she went to work and it was bloody freezing

maquiladora wrote: »

It's an automatic weather station, precipitation type errors happen sometimes.

Oh yeah, i know, im just saying it was nice to see it mentioned.

It's always safe to assume, that no matter what kind of snowmageddon is indicated by whatever model or stats for Mainland Europe and it's close neighbour the UK, that little ol Ireland is just a touch too far out into the Atlantic to see much if any of it except in exceptional circumstances. Let's not even get into the snow shadows when by a tiny stroke of meteological luck we get some -8 850's over us.

ie. no matter what you hear or where you hear it, assume it ain't happening in our neck of the woods, and you won't be disappointed, but once a decade or so you'll be pleasantly surprised.

Gonzo wrote: »

the above post is so true, ive lost countless times on the amount of times over the past 30+ years that our very close neighbour gets plastered with snow, sometimes even as far west as the welsh coastline can be sub-zero and snowy, while the east coast of Ireland and further west is +10C and misty drizzle. From 1993 onwards we've had so many close calls that just fail to make it to our shores, at least 2009/2010 worked out tho! Let's hope this winter works too!

Exactly, countless times!
I seem to remember a -18c somewhere in eastern England around this time while we were stuck in our usual 10c muck! We're closer to the Azores high than the Scandinavian high
http://www.wetterzentrale.de/archive/2012/brack/bracka20120203.gif
(I think 20c+ is a real possibility in the Dublin area by the end of the week)

Creative Juices wrote: »

I have a feeling in my bones that we are going to see some decent know this winter.
Even if we get it in the mountains I will he happy.
When will we start to see some exciting charts?

Around 15th of November, possibly. I think the Atlantic will be fairly hard to shake before then.

LordNorbury wrote: »

I love nothing more than heading up the Dublin Mountains and finding snow, it's just amazing to walk in it... Even if there isn't any at ground level...

How do you reach this elusive flying snow that is not a ground level.