Jump to content
Cold?
Local
Radar
Snow?

OCTOBER PATTERN INDEX (OPI) MONITORING WINTER SEASON 2014-2015


Recommended Posts

Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.

    Unless you of course are going to put the block on it because you think its a wind up.

    Link to post
    Share on other sites
    Spotted a post you think may be an issue? Please help the team by reporting it.
    • Replies 1.5k
    • Created
    • Last Reply

    Top Posters In This Topic

    Top Posters In This Topic

    Popular Posts

    As ever, a great summary of how things stand from Ed and I think for the last 19, or pretty much 20 days now we have all been waiting for this point in the month and beyond. It's been rather 'fun' wat

    The discussion of the OPI index trend is understandably causing a lot of interest and (cautious) excitement amongst members after Riccardo's very interesting opening post that started this thread. The

    The monitoring page of the “October pattern index†(OPI) is presented. The OPI index  represents a analytic synthesis of the October hemispheric pattern at 500 hPa, and shows from  previous studi

    Posted Images

    Posted
  • Location: Warsaw, Poland. Formerly London.
  • Weather Preferences: Four true seasons. Hot summers and cold winters.
  • Location: Warsaw, Poland. Formerly London.

    Is someone having a bubble flogging this long dead horse?

    Link to post
    Share on other sites
    Posted
  • Location: Woodland Garden, South Yorks
  • Weather Preferences: Warm and Humid weather, Thunderstorms
  • Location: Woodland Garden, South Yorks

    Not this pointless cack again.

    Link to post
    Share on other sites
    Posted
  • Location: Sedgley Black country 731ft 222 metres
  • Location: Sedgley Black country 731ft 222 metres

    Nice to see you having a punt Feb  something else to build our hopes up 

    Link to post
    Share on other sites
    Posted
  • Location: Isle Of Wight - Newport
  • Weather Preferences: Cold winters/Hot summers
  • Location: Isle Of Wight - Newport

    Fair play for having a crack Feb!  Whats wrong with someone putting their thoughts and theories in practice?

     

    Don’t know why people are happy to shoot people down in flames without giving them a chance, so what if it doesn’t work out no harm in trying and we should not stifle them from trying.

    Some on here need to take a minute to think what they say.

    Good luck Feb, hope you are willing to post your thoughts.

    Edited by Bobafet
    Spelling
    • Like 5
    Link to post
    Share on other sites
    Posted
  • Location: The Purbeck Microclimate, Dorset.
  • Weather Preferences: Gales, T-storms, Heavy Rain, Heat, Cold - Love it all.
  • Location: The Purbeck Microclimate, Dorset.
    39 minutes ago, Bobafet said:

    Whats wrong with someone putting their thoughts and theories in practice?

    Two massively different things.

    Explain to me, how does one try to complete a theory, that, and let's be honest, failed. And, trying to do so without all of the information to begin with?

    The website got terminated and the whole thing went in to obscurity. 

    The resurrection of this thread is just for a laugh, nothing else.

    • Like 3
    Link to post
    Share on other sites
    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
    53 minutes ago, Bobafet said:

    Fair play for having a crack Feb!  Whats wrong with someone putting their thoughts and theories in practice?

     

    Don’t know why people are happy to shoot people down in flames without giving them a chance, so what if it doesn’t work out no harm in trying and we should not stifle them from trying.

    Some on here need to take a minute to think what they say.

    Good luck Feb, hope you are willing to post your thoughts.

    Will do, have to work out whether to go on the average of the whole days or just the polar profile on the one chart - the midday analysis chart. One early snag which would have made things easier if more charts and posts on the 2014 one were available.

    • Like 2
    Link to post
    Share on other sites
    Posted
  • Location: Isle Of Wight - Newport
  • Weather Preferences: Cold winters/Hot summers
  • Location: Isle Of Wight - Newport
    14 hours ago, Mapantz said:

    Two massively different things.

    Explain to me, how does one try to complete a theory, that, and let's be honest, failed. And, trying to do so without all of the information to begin with?

    The website got terminated and the whole thing went in to obscurity. 

    The resurrection of this thread is just for a laugh, nothing else.

    But why shoot someone down before they have even had chance to put their thoughts in practice.

    You may well be right with your thoughts but at least give a person a chance to at least have a go at their idea.

    i just think we are too quick to jump on people - but then that is the nature of this country at the moment - too quick to put people down and not have reasoned discussions.

    • Like 3
    Link to post
    Share on other sites
    Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

    It's ironic that people are wasting their time attempting to convince someone that they're wasting their time...

    As long as your time isn't being wasted, does it really matter if you think feb is wasting his?

    I'm of the opinion that the idea is probably cack, but I'm not bothered by someone "reopening the investigation", as it were.

    PS: I realise that in lecturing people about wasting their time, I, too, have probably wasted mine ?

    Edited by Relativistic
    • Like 6
    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs

    As i replied in the other thread, I'm sure there is a link between October pressure patterns and the winter AO, it links in with the snowcover advance index. 

    These are some of the top negative OPI years, and top snowcover advance years i believe too, you can see the theme is higher pressure over northern siberian, the Taymyr peninsula, and the trough underneath, i havent been through all the years but it seems this synoptic definitely favours a negative wintertime AO.

    751534168_octgoodforcold.thumb.png.0498379a06b4b3f626b1859fcf81215b.png

    As we know, 2014 was a bust, so of course it isnt perfect, but there is something in it. Obviously the AO being negative is only one part of trying to get cold to our shores, but the AO/NAO correlation is about 0.7 if i recall correctly, so again we can start to build a picture of winter based off the October pressure patterns, the key thing is, and a lot of people forget this, is to never use one thing in isolation.

    October is the month where winter chasing really begins for many, going to be another interesting year, last year came so close to delivering, and an extremely weak PV going into winter, will we see the same this time, could it be the norm now with low sea ice and perhaps solar taking effect? As ever, time will tell!

    Regards

    • Like 3
    Link to post
    Share on other sites
    Posted
  • Location: The Purbeck Microclimate, Dorset.
  • Weather Preferences: Gales, T-storms, Heavy Rain, Heat, Cold - Love it all.
  • Location: The Purbeck Microclimate, Dorset.

    I have said this before.. if you look in to it deep enough, you'll find some kind of link with the AO/NAO for every single month of the year.

    It makes me wonder why it's taken 5 years for this thread to appear again? Surely, someone could have used this to predict the milder Winters, no?

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
    On 05/10/2014 at 21:23, Steve Murr said:

    I just logged in on my mobile-

     

    Yesterdays figure had sat there @ -0.23 all day

     

    -2.12!!!!!

     

    That puts the running mean out to day 5 @

     

    -1.2,-0.8,-0.3,-0.2,-2.2

     

    = -.94

     

    From the OPI graph & years I research ( post 76) the easterly QBO years Sub -1.5 for the MONTH were

    76/77

    84/85

    09/10

     

    Here is the DJF analogue.

    post-1235-0-30729100-1412540049_thumb.pn

     

    If we make the ASSUMPTION that because the OPI correlates nearly 100% to the AO - especially is negative AO years then we would include the following winters with Easterly QBOS ( this is because the -AO was so negative the OPI would have to have been the same)

     

    52/53 - (weak Easterly)

    62/63 - STRONG Easterly- identical to this year.

    68/69 - Easterly

    00/01 - Easterly

     

    Then this appears.....

     

    post-1235-0-08869600-1412540534_thumb.pn

     

     

     

    Out of EVERYTHING that people are watching at the moment the OPI index is the most important to give us a clue into winter..***

     

    S

    Were these the actual figures for each day or did it suddenly jump up massively at D5 - could do with knowing individual days.

    Link to post
    Share on other sites
    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

    I don't wish to get involved in is it or not a reliable indicator but I did this research some while back

    Is the OPI index reliable when comparing CET data with values for the OPI of lower than -1.7?

    This is a very un scientific take on the possible link between the OPI and ‘cold’ CET winters. For cold I have taken winter months with 2 or more below average months. Winter being taken as December, January and February. Temperatures in degrees C.

    The years of OPI below the figure quoted are:-

    1976=-1.75     winter 1976/77

    1978=-1.9                   1978/79

    1984=-1.8                   1984/85

    1985=-1.9                   1985/86

    2009=-3.15                 2009/10

    2012=-1.76, so -1.7 to the first decimal point.           2012/13

    The CET data is that available on this site http://www.personal.dundee.ac.uk/~taharley/centralengav_temperat.htm

    And has the average based on 1971-2000

    December=5.1, January and February both at 4.2; this gives a mean of 4.5C.

    1976/77=2.0, 2.8, 5.2

    1978/79=3.9,-0.4, 1.2

    1984/85=5.2, 0.8, 2.1 

    1985/86=6.3, 3.5, -1.1           

    2009/10=3.1, 1.4, 2.8 

    2012/13=4.8, 3.5, 3.2

    Before examining the above data we also need to see when the above criteria for cold winters CET values were satisfied but did not show an OPI of -1.7 or lower.

    The following winters fell into this category

    1981/82=0.3, 2.6, 4.8  mean=2.6

    1982/83=4.6, 6.7, 1.7  mean=4.3 so requirement not really met with the mean

    1990/91=4.3, 3.3, 1.5  mean=3.0

    1995/96=2.3, 4.3, 2.5  mean=3.0

    1996/97=2.9, 2.5, 6.7  mean=4.8, so again the mean makes this winter not relevant in spite of 2 ‘cold’ months.

    2010/11=-0.7, 3.7, 6.4            mean=3.1

    And the OPI very positive=1992=1.75, winter =1992/93=3.6, 5.9, 4.6            mean=4.7(so just missing out)

    So tidying the above up leaves 1981/2, 1990/91, 1995/96, 2010/11 with CET fitting the criteria used. A total of 3 years when the OPI did not come anywhere near -1.7, the actual values, in the same order as the CET years given above was:-

    -0.4,0.55, -0.65, -0.85. Looking at it another way, only 1 of these years did not show a –ve OPI.

    We therefore have 6 years with the OPI and CET values agreeing with the theory of OPI indicating cold winters and 4 winters with cold CET values (as defined above) with the OPI giving no clue to this occurring.

    Putting the OPI in order of negativity with the winters alongside gives

    1          2009=-3.15     2009/10=3.1, 1.4, 2.8  mean=2.43      3

    2          1985=-1.9       1985/86=6.3, 3.5, -1.1            mean=2.90      2

    3          1978=-1.9       1978/79=3.9,-0.4, 1.2 mean=1.57      1

    4          2012=-1.8       2012-13=4.8, 3.5, 3.2 mean=3.8        5

    5          1976=-1.75     1976/77=2.0, 2.8, 5.2 mean=3.33      4

     

    If we compare these figures with those years when the OPI did not give an indication, we have

    1981/82=0.3, 2.6, 4.8  mean=2.6; this would rank 2 in the above winters

    1990/91=4.3, 3.3, 1.5  mean=3.0: this and 1995/96 would rank joint 4th

    1995/96=2.3, 4.3, 2.5  mean=3.0

    2010/11=-0.7, 3.7, 6.4            mean=3.1; even this one shows a mean winter temperature below the 4th in the table above. None of the above had all 3 winter months below average whilst 2 of the winters in the above table did so.

     

    Without doing any statistical tests on either of the above results it seems to me that the expectation, by some, on Net Weather, of this being the key to predicting winter are somewhat off the mark. As I suggested at the beginning it is a non scientific explanation and please feel free to shoot this post down if you wish.

    One other point is that the period of data is, relatively, small for predictive purposes. A minimum of 30 years is used for climatological records but for something of this type, an attempt to use a predictor much longer periods are the norm.

    Maybe someone could discover in the winters I have highlighted what the QBO etc showed as well as this might refine the results? Was the winters that supported the theory west or east based NAO. Equally what about those winters with below average months what was the QBO and NAO showing?

    I remain, sceptical of any claim that this will give a reliable indication ON ITS OWN, but it may be another indicator to use with others already in use. One thinks of the SAI and  Tropospheric influences to name just two.

    Interesting to play around with the data though.

     

    No doubt someone will knock holes in the above.

    • Like 4
    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs

    Just to back up the idea of the link between October pressure patterns and winter AO/NAO, a nice exercise here by Ant Masiello, again we see the higher pressure over the Taymyr region during October going into negative AO/NAO winters, so it certainly seems like a link there, Aluetian low possibly too? So as said before, the SAI and the OPI are quite closely linked, it's all about starting those feedback loops going into the winter season, ie weaker PV, stronger Siberian high, PV more prone to 'Attacks' etc.

    Again, nothing to be taken in isolation but it's all linked.

     

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    I've never felt easy about what appear to me as 'reverse correlations'; given enough paring-down, we end-up with a sample of one: October 1962 begat January 1963...?

    Is it really any wonder, then, that the annual round of 'Oh golly-gee, doesn't such-and-such an October pattern look just like 1962...and the rest was history!' statements have success-rate of zero?:oldgrin:

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs

    I really don't understand why people feel it is so far fetched to see a link between the October pressure patterns and wintertime AO, nothing is ever 100% and i don't know how many times I have to say that! The pressure patterns link in with Cohens SAI theory, it is all linked, so then come the end of October we can start to build up a picture for winter, but of course what happens through November is crucial. So  for now we watch and wait to see what happens through this October, the winter madness is approaching at break-neck speed ?

    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs

    Not a bad anomaly here with strong high pressure over the Taymyr region on the GEFS mean this morning, this is what we want to watch over the course of this month, maybe looks for an Aluetian low developing too? ? 

     

    GFS ens mean.png

    Link to post
    Share on other sites
    Posted
  • Location: bingley,west yorks.81 absl
  • Location: bingley,west yorks.81 absl

    Excuse my ignorance but why is it linked to solely October?

    • Like 1
    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs
    1 minute ago, joggs said:

    Excuse my ignorance but why is it linked to solely October?

    The wintertime AO? Not linked soley, but this is the time of year the PV is spinning up, so of course we start the feedback loops etc etc, again, nothing in isolation and things CAN change quickly, it's all part of the puzzle! 

    Link to post
    Share on other sites
    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.
    37 minutes ago, coldwinter said:

    I really don't understand why people feel it is so far fetched to see a link between the October pressure patterns and wintertime AO, nothing is ever 100% and i don't know how many times I have to say that! The pressure patterns link in with Cohens SAI theory, it is all linked, so then come the end of October we can start to build up a picture for winter, but of course what happens through November is crucial. So  for now we watch and wait to see what happens through this October, the winter madness is approaching at break-neck speed ?

    Because, if there is such a link, it's so tenuous as to be undetectable...other than in retrospect; by which time it's about as much use as a chocolate fireguard?

    Think chaos, entropy and thermodynamics?:oldgood:

    Link to post
    Share on other sites
    Posted
  • Location: Lincs
  • Location: Lincs
    3 minutes ago, Ed Stone said:

    Because, if there is such a link, it's so tenuous as to be undetectable...other than in retrospect; by which time it's about as much use as a chocolate fireguard?

    Think chaos, entropy and thermodynamics?:oldgood:

    It's not "so tenuous as to be undetectable" All part of the puzzle, and putting the puzzle together through Autumn into winter is what many enjoy on here ?

    Link to post
    Share on other sites
    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.
    4 minutes ago, coldwinter said:

    It's not "so tenuous as to be undetectable" All part of the puzzle, and putting the puzzle together through Autumn into winter is what many enjoy on here ?

    Okay then...give us one example how using said 'link' has yielded consistently useful results? The proof is, after all, in the pudding...

    Link to post
    Share on other sites
    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
    Just now, Ed Stone said:

    Okay then...give us one example how using said 'link' has yielded consistently useful results? The proof is, after all, in the pudding...

    I refer the right honourable gentleman to the first dozen pages of this thread where Steve Murr did some re-analysis.

    Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now
    • Staying cool and showery with heavy, thundery downpours

      The weather continues on with its cool, showery and unsettled pattern, with more heavy downpours during the next few days. Then, to finish the week, a deep low arrives bringing a spell of wet and windy conditions. Read the full update here

      Netweather forecasts
      Netweather forecasts
      Latest weather updates from Netweather

      UK Storm and Severe Convective Forecast

      UK Severe Convective & Storm Forecast - Issued 2021-05-18 06:21:01 Valid: 18/05/2021 0600 - 19/05/2021 0600 THUNDERSTORM WATCH - TUES 18TH MAY 2021 Click here for the full forecast

      Nick F
      Nick F
      Latest weather updates from Netweather

      Strong winds from an Atlantic low later this week adding to cool, wet May

      May 2021 has been colder than average with a lot of rain for some parts of the UK. A low pressure heading in for the end of the week could bring gales. Read more here

      Jo Farrow
      Jo Farrow
      Latest weather updates from Netweather
    • Recently Browsing   0 members

      No registered users viewing this page.

    ×
    ×
    • Create New...