Penrith Snow

Regarding temperatures over the coming 10 days I would expect given the strong WNW flow ranging from well below average in NW Scotland to above average in SE England due to it's longer exposure to warm sectors. This kind of cool zonality often results in near or even above average temperatures in Central England as the mild sectors can push temperatures above 10c for a short time even though temperatures are fairly low for long periods. The very snowy zonal spell of January 1984 is a classic point as monthly temperatures were near normal in Northern England despite frequent and heavy snowfalls and 15+ days with lying snow! This is the reason for the MetO prediction of mean temperatures a tad above normal. Andy

Good ECM run, if I can't have deep cold easterlies and northerlies this is my second best winter weather set up with fast moving depressions pulling in cold polar air as they pass to the east of the UK before the next depression turns things temporarily milder as the warm sector comes through. This leads to some very interesting weather with gales, sleet, snow, rain, sunshine, frost, just about every element and sometimes on the same day! You can't be interested in the weather and not enjoy that. Ok I appreciate I am looking at this from a Cumbria prospective and conditions will not be as varied in Central London. My only concern is that such cool zonal spells tend to be followed by a longer spell of milder westerly winds as the Atlantic high pressure moves into Biscay and this seems to be happening at +240, but that's a long way off and there is plenty of great weather to come in the meantime. Andy

Oh dear, not a good morning is it and yet again the reputation of ECM hits the dust as it drops amplification in the medium term and joins GFS. On the positive the flow does look like having a cool, north westerly element so some snow likely over high ground in the north and it will feel cold. In the long term we just have to wait and see but we need the PV to move out of Greenland to get any chance of real cold and in the current set up this could take weeks. But don't despair some of our best winters of the past had zonal Decembers so all is not lost. BTW good analysis by the MetO and I admire their honesty, it's a puzzle that the models are going against the background signals but how strange that the creators of the models do not know why! Maybe they have joined forces and become self aware.......Skynet lol Andy

Knocker, It wouldn't take a massive shift in Global Pressure patterns to shift the Atlantic blocking high north and east and develop a through into Scandinavia thus opening the cold floodgates from the north. The models have tried but failed to do this recently but it could be only a matter of time. I Would be much more concerned if our Atlantic High was a massive Bartlett stretching from the Azores to the Balkans, now that would be hard to shift but the current set up could (not saying it will) change very quickly. The problem for NW members is that Winter starts tomorrow and given the right conditions it could be very cold and snowy like 2010 but the reality is that snow in early December is as rare as Steve M's Hens teeth and always has been. I still believe in the OPI! Andy

Yes, ECM has all but dropped it's several northerlies, so too has GEM and the models have very much moved into line. However, we have also lost the dreadful Biscay High charts Gfs was putting out a few days ago so we are left with very benign conditions with dry weather a few frosts and temperatures never far from normal. For early winter it could be worse and it many ways it's the ultimate blank canvas and anything could happen. Be thankful that you didn't book a late November break to the Canary Islands which are enduring repeated storms as cut off lows slide underneath the mid Atlantic High, in Lanzarote on Friday the capital Arrecife recorded 130mm of rain, for this near desert island that's about a years worth! Andy

Back on topic the ECM is superb, ignore the detail it's the trend that matters. Andy

Nothing good is ever going to come of this Russian High which is unable to ridge westwards so I would prefer to see the Atlantic breaking through for a while and then pressure rising in the Atlantic and week or two down the line. This stalemate is useless where a cool westerly flow leads to at least the possibility of a toppler which can develop into something more interesting. I maybe shot down for saying it but it's time to press the reset button. Andy

We shouldn't get too hung up on the very cold weather in the US, some of the coldest winters ever in the US occurred in the late 1970's and coincided with several cold winters here including 1978/79. The coldest ever winter in the US 1976/77 was also cold and snowy here. Andy

GFS run certainly puts the mild weather of October behind us and if verified would result in slightly below average conditions for the first two thirds of November. No zonal train and if you want a cold winter November is shaping up just fine with plenty of embryo Northern blocking. Andy

And we all know how accurate the professional models are! Lol At the moment the limited sample provided by the OPI is the best we have and I can not remember any autumn in the last 6 years where the professional models forecasted a cold winter despite 4 out of the 6 being cold or very cold! These same models did a crap job predicting the good UK summer this year and last winters storm loaded washout. I am not a betting man but if I was my money would go with the OPI than the dubious model runs compiled by the professionals. Andy

Fantastic Steve, some really good analysis their taking into account all the broad scale features. To me this type of long range forecasting is so much better than merely running a computer model forward 4 months then taking the Ensemble mean which essentially is what the MetO does, that even with MRF is so prone to errors and the butterfly effect. I am really confident of a very cold winter in 2014/15, I have only ever issued a winter forecast in 2009 and 2011 because of the strong signals at the time and got it more or less right both years (cold in 2009/10 mild in 2011/12) and I am equally confident this year that winter 2014/15 will be cold. By the way I sat on the fence in other recent years because I thought signals were too conflicting so I don't think I could ever make it a career of it! Let the countdown begin. Andy

I am not computer illiterate but the jargon around these programmes is beyond me, I went on the the Weather Display website and I was totally lost after reading a few minutes! The TFA software is basic and prone to bugs but at least you don't need a degree in programming to understand it. Will get one of the kids to have a look again at Weather Display but why oh why is life so complicated. Grumpy Old Man

Despite the new research I still can not imagine the UK getting a strong zonal winter following the very low OPI in October. Yes, other factors will come into play but with an OPI below -1.5 the correlation is so strong. We will never know until the time whether the weak Vortex brings a good Scandy Block or watch as cold heads into France but I really can not see the zonal washout of last year reappearing. The Vortex will ramp up during November which will be very zonal but I would bet a 1000 pounds that the Vortex will be flopping about like a drunken sailor before Christmas. I am keeping the faith and for those going back into the MetO LRF camp all I can say is Good Luck. Andy

Thanks that's great I will give it a go. I am surprised the Nexus isn't more popular as all the units rain, wind, temp etc are separate and wireless. I thought about buying the Davies Vantage Vue but it's expensive and all the units are in one place so either the rain gauge is too high or the thermometer too low! The manufacturers of these weather stations should read the excellent 'Weather Observers Handbook' which you can still download from the MetO site, clearly the Nexus is one of the very few electronic weather stations that can meet the internationally agreed criteria. Even the much praised Vantage Pro suffers from the same limitations and it's no good having accurate instruments if they are sited in the wrong place! Andy

I have just purchased my second Nexus Weather Station after the rain gauge and wind vane failed on the old one, it made more sense to buy a whole new station at £150 than a new rain gauge etc at £90 and now I have two consuls around the house reading off one set of instruments....Great! HOWEVER, as ever the software that come with the Nexus has more bugs than a mouldy cheese sandwich so does anyone know of any other Weather Data Recording software I can use from the internet preferably for free? I understand the Nexus is not compatible with several software packages but will it work with any? What about Weather Display? Any answers most welcome. Andy

It's been a great thread with some really good informative posts. We should finish I reckon with an OPI of about -2.3 which would be the second lowest recorded even 1978 was only -1.8! Now, what could possibly go wrong........lol Andy

Yes, but 1990 was only slightly positive and the other years only slightly negative. The correlation only really kicks in with anomalies exceeding plus or minus one each way. I would say anything between plus and minus one should be regarded as neutral and the OPI signal likely to be overwhelmed by other factors, this was certainly the case in 1997/98 with its mega El Niño. Winters 2002/03 and 203/04 were not without interest either being two of the better winters of the 2000's. Andy

What signals are pointing to a mild winter? Obviously there must be some as all the seasonal forecasts point one way but what are they? Anyway I ignore all the seasonal models as they are pants, last year was a classic example as most including the MetO indicated a mid latitude block with cool, dry weather in the UK, how wrong can you be! I have never seen the MetO correctly model a cold season. Andy

I remember well Autumn 2009 and no one but no one was expecting a very cold winter as the Autumn was very non-descript, only November was noteworthy in that it was exceptionally wet. Even in early December there were few signs of the cold to come but then mid month pressure built strongly over Scandinavia and the rest is history. You just can't look at the UK weather in Autumn as an indicator of the winter to come as cold winters have been preceded by all types, however, a strong zonal dominated Autumn is the one not to have. Andy

Looking at the historical OPI data every October since 1976 with an OPI below -1.5 has been followed by a cold winter in the UK without exception, not always very cold but below average never the less. Ok it's only 38 years of data but the evidence is compelling. It's a shame Ricardo's team haven't gone back another 40 years which would be even better. Andy

-2.5 sounds good, so off to B&Q today to buy a large bag of rock salt a new snow shovel a sledge for the grand children and snow chains for my Fiesta. That confident? Absolutely! Andy

Any winter forecast based on the OPI has got to be better than the formula the MetO use! Remember their 2009/10 winter prediction lol Had we known about the OPI in October 2009 none of us would have predicted a mild winter! Andy

-2.4 would still be very good and the OPI is already taking into account the less favourable synoptics over the next 7 days which ais hardly FI when looking at the broad scale pattern. If it's below -1.5 then I think a cold winter is ahead and will put my reputation on the line by telling people so, it's the time of year everyone asks me what the winter will be like! This year the answer to that might be easier than normal. Andy

Looking at Steve's analysis I would say the OPI is a very good forecasting tool when the value is above 1 or below -1 then it seems almost 100% correct. Between 1 and -1 I suspect other factors can overwhelm the OPI signal. If I am correct then last winters mild washout was inevitable as is the coming winter 2014/15 freeze! We will see. Andy

In hindsight all the signs were there in October 2009 for a cold winter to follow yet that same month the MetO issued it's now famous mild winter 2009/10 prediction. After forecasting a BBQ summer in 2009 the winter forecast was there last seasonal forecast. Good decision chaps. I am really excited about the OPI as I always suspected that the seeds of winter were sown in October. Andy