If the OPI verifies over time then the MetO may well incorporate that into their contingency planners forecast along with everything else.  But it will still be a probability forecast, because that is all it is intended to be.

btw if the Contingency Planners was based just on the MetO model - or if the MetO Model was only used for the Contingency Planners -  then I would be far more critical of them!

I see the usual Meto bashing is alive and well

The Meto are likely to be better informed and more able to produce forecasts than many as they have better data.

If you believe that the way to creating better LRF's is to improve computer capacity then their recent hardware acquisition makes sense.

The test of whether it is money well spent will come with accuracy return statistics measured against older outcomes but I would say that trying to produce LRFs, whilst an admirable intention, is fraught with problems and likely to remain so for some time.

As for comments about OPI, well to my eye its just another straw to cling to as we approach winter. I don't even think this is especially new in general terms bearing in mind people on TWO have linked Octobers weather to the approaching winter since I started here in 2004.

My interpretation is that DRY Octobers may possibly lead to an increased chance of a colder winter, not warm ones. This, of course, may simply be an anomaly and given the chaos of weather in our latitude I'd wager it probably is.

As for the MetO the best organisation in the world for short to medium term forecast, but anything beyond that

I'll just grind that axe for you

Couldn't agree more Dave

Flirts of Easterlies in FI to only get smashed by the Atlantic Steam train again and again..... Deja Vu?

Good job winter 2014/15 has not even started 

The evidence that dry Octobers are followed by colder than average winters is very weak There is in the period from winter 1874 to winter   literally zero correlation between  CEP (Central England Precipitation in October and the CET of the following winter,Taking more extreme rainfall values there is  little difference in the mean CET of the following winters and a correlation of only 0.2.

The problem of selecting extreme OPI/AO indexes is that although they may be good indcators they occur in very few years, so are little help in the majority of years.

Over the past few days, CFS has been trending ever-stronger with blocking around Greenland for December.

If the whole Cohen theory was to come into fruition, this is the sort of anomaly that would emerge, even though it would be preceded by a period of low heights to the NW of the UK - the theoretical progression transitions from a zonal setup for the UK to a heavily blocked one... though it predicts a slower rate of progression than the above chart suggests.

There are some on the other site that believe we're going to be following an accelerated version of Cohen's theory. I think that would be good fun - but really it's all just speculation at this point in time and relies on some good fortune as usual.

The current CFS offering for the post Christmas period.  Say 'halo' to Euro-trash High.

Have to agree with you there solar. The OPI  nothing to do with dry Octobers

and the Meto whom I have the utmost respect for are as you say specifically a short to medium forecaster by the nature of their main customers needs. They freely admit that their seasonal or contingency planners outlooks are experimental, and as such are not really likely to be any better than anyone elses even if a bit more science may be involved.

The OPI is interesting for me living in the relatively snow free area of central south Dorset because all of its negative value years have been followed by winters that actually produced the goods to some extent in my locale whereas the positive years did not, so on a purely personal imby basis the OPI has proved better then any other forecast at picking out cold and snow for my location.

So I am awaiting the coming winter with great interest

I have a `gut feeling` this coming winter is going to be back loaded with the best chance of a cold spell

in February/March. Before then a continuation of above average temps and rainfall and a new cet record

this year being set,possibly 11c+

The OPI also won't tell us about our Winter IMO ,it's just another stat to get the tongues wagging

Events in the stratosphere are likely to get quite interesting over the next 10 days or so. There is a good summary explanation of how activity in the stratosphere at this time of the year can impact on our weather down the line http://www.markvoganweather.com/2014/11/12/w-europe-atlantic-still-rules-explanation-stratosphere-role-cold/

The polar vortex has already been displaced a little this Autumn due to wave 1 activity. The current charts at both 30hPa and 10hPa show the vortex has drifted towards Scandinavia.

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t30_nh_f00.gif
http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t10_nh_f00.gif

There is still a fairly tight core to the vortex at the moment though. However, there are already signs, particularly at the 30hPa level of significant warming on the Siberian side of the pole.

Currently temperatures in the stratosphere are slightly cooler than average as this chart shows

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/30mb9065.gif

If we look ahead to the forecast charts for T240 we see that at 30hPa there is very strong warming over Siberia and the temperature of the vortex on our side of the pole has warmed as there are no areas below -75C. The vortex is being elongated as well

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t30_nh_f240.gif

At 10hPa there is also significant warming over Siberia. The vortex though has continued cooling at this height and is now below -80C at its core although it is again showing signs of elongating.

http://www.theweatheroutlook.com/twocommunity/default.aspx?g=postmessage&t=13780&f=2

We have seen a fair amount of wave 1 activity so far this Autumn which is now starting to impact at the 20-25km heights and would explain why the vortex has been slightly displaced

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_WAVE1_MEAN_ALL_NH_2014.gif

We need to see some wave 2 activity in order to seriously disrupt or even split the vortex. Something to keep an eye on in the coming weeks.

You can see from the 2009 charts for example the extent of wave 1 and wave 2 activity in December of that year

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_WAVE1_MEAN_ALL_NH_2009.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_WAVE2_MEAN_ALL_NH_2009.gif

I'm looking forward to Gavin P's next JMA analysis ( Cold Push Western Europe Dec)

Sounds rather like 2012/13 then.

Yes, just as well "Gut feelings" is not used by the met office😆

Does anyone know if moomin75 is making a winter forecast?  Ive justr been looking through the archives and noticed one or two of his forecast, which were very very accurate to the actual conditions.

Searched for his profile and it came up he hasnt posted since july?

Thoughts

Old Moomin normally pops his head back in here (mainly model output thread) by December. Have you checked over on the 'other channel'? (net weather)

Good evening,

I've been researching past winters for quite a while now and I have come up with my thoughts on this winter. My thoughts for this year will include past instances of the OPI below -1, ENSO, Easterly QBO and historical data including Sea Surface Temperature anomalies, so here goes.

The years I have pinned down from past winters include, 1976/77 - 1986/87 - 2009/10.

2012 came very close, however, the ENSO turned negative (neutral) during the winter period and although the current ENSO is neutral it certainly wont turn to a negative neutral and in fact looks like becoming a weak El Nino.

76/77 Had 2 out of the 3 winter months with below average temps 

86/87 also had 2 months with below ave temps 

09/10 well, all 3 were below .

So one could suggest that we could be in for at least 2 colder than average months during winter based on this, with the AO likely to be negative throughout winter. The NOA will be the player should this also turn negative, although this is far more uncertain. This said here are some NOA scores from the years selected. These are monthly figures:

1976/77

Dec: -1.57   Jan: -1.72    Feb: -1.0

1986/87

Dec: 0.83    Jan: -1.85    Feb:  -1.27

2009/10

Dec: -1.88   Jan: -1.8    Feb:  -2.69

Some very negative NAO scores there so the signals are also good and its possible cold pooling in the Northern Atlantic has a part to play in this. We currently have a cold pool in the Northern Atlantic

This year is certainly a far cry from last year and I personally don't expect anything like last years pattern, in fact I fancy quite the opposite. There are already signals suggesting some sort of warming in the stratosphere (wave1) with hints of wave2 and also the NAO is trending negative at month end. However I feel we wont really see our proper cold shot until around the last 3rd of December, but once the pattern changes to cold, it may well be in for a while, perhaps until the end of January or early Febuary. Of course milder intrusions will occur during this period but the cold pattern will be the dominating factor, more likely in the form of a NE/E'ly flow.

 Fascinating post weatherstu.Hope you are right!.I would love a repeat of 2009/10.However one factor is miising."009?10 fell at the time of an extended solar minimum.The sunspot  minimum has been linked to blocked winters.At present however we are just apst sloar maximum so there is no helping hand from a solar minimum.