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


Riccardo

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Posted
  • Location: Dulwich Hill, Sydney, Australia
  • Weather Preferences: Hot and dry or cold and snowy, but please not mild and rainy!
  • Location: Dulwich Hill, Sydney, Australia

That's what I thought. So how have you come to a positive OPI output for October? Quote your post 'Moreover I tell you that currently the OPI is abaut +1/+1.5, so the winter will be probably a AO++ winter."

??

 

The quote was for October 2013 last year so "currently"  is for october last year which was a positive OPI.

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Posted
  • Location: Yatton, South of Bristol
  • Location: Yatton, South of Bristol

??

 

The quote was for October 2013 last year so "currently"  is for october last year which was a positive OPI.

The way it reads is referring to the information below, not above the quote. People shouldn't copy and paste other peoples comments from other sources. Anyway..we are negative at the moment. This year will be interesting to whether the OPI is a good tool or a garden path tool. You can just read the charts and gain the same information.

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Posted
  • Location: Inbhir Nis / Inverness - 636 ft asl
  • Weather Preferences: Freezing fog, frost, snow, sunshine.
  • Location: Inbhir Nis / Inverness - 636 ft asl

Very negative territory I'd say, looking promising at this stage.

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Posted
  • Location: Hadleigh, Suffolk
  • Weather Preferences: An Alpine climate - snowy winters and sunny summers
  • Location: Hadleigh, Suffolk

Latest model output continues to be very encouraging for months end. Of course they are FI charts and subject to chops and changes with the exact height profile come the day, but importantly all models are forecasting positive heights continuing to impact the Polar region. Model forecasts for 30th/31st Oct:

 

GFS: post-20040-0-68944500-1413793045_thumb.p GEM: post-20040-0-04974800-1413793073_thumb.p  ECM: post-20040-0-94990700-1413793110_thumb.p

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Posted
  • Location: Wellseborne, Warwickshire
  • Weather Preferences: Southerly tracking low pressure in winter. Hot and thundery in the summer
  • Location: Wellseborne, Warwickshire

The way it reads is referring to the information below, not above the quote. People shouldn't copy and paste other peoples comments from other sources. Anyway..we are negative at the moment. This year will be interesting to whether the OPI is a good tool or a garden path tool. You can just read the charts and gain the same information.

If you think about it a neg AO in October will result in an increase of snow cover during the month , may not be in Siberia but a negative AO will normally spill cold weather to more southern latitudes (relative for time of year) so the OPI and the SSI is in my opinion intrinsically linked .

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Posted
  • Location: Portrush. (NI) UK
  • Location: Portrush. (NI) UK

That's OPI for October 2013 which was positive but AO was slightly negative until a small part of Feb 2014.

OPI October 2014 is currently running very negative. -3.04.

As last year was the most up to date index. I was analysing it first with what the outcome was.

Then trying to predict Winter 2014/15 with what the current Index is and what the we should expect if the OPI is a valid long range forecasting model/tool.

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Posted
  • Location: Ripon , North Yorkshire 41m/135ft ASL
  • Weather Preferences: heat and cold, storms and blizzards...zonal a no no
  • Location: Ripon , North Yorkshire 41m/135ft ASL

What does the change of colour on the graph represent? 

 

post-18134-0-29085200-1413796900_thumb.p

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Posted
  • Location: Portrush. (NI) UK
  • Location: Portrush. (NI) UK

What does the change of colour on the graph represent? 

 

attachicon.gifImage.png

Within the 10 days to end of month more solid data than FI.

Many have said on here that by the 21st of October the OPI shores up a final index result and so does not deviate too much from this figure to final result. It most likely will not go below a -2.5. But it looks like it'll be more negative than that.

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Posted
  • Location: Near King's Lynn 13.68m ASL
  • Weather Preferences: Hoar Frost, Snow, Misty Autumn mornings
  • Location: Near King's Lynn 13.68m ASL

Last year's (someone found this earlier in the thread, so kudos to them):

 

OPI002.png

 

So I suppose red = positive and blue = negative and the colour changes to reflect the increased confidence in the final figure.

 

I also surmise that the 3 massive outliers in the early part of last year's progression is why they take care when considering each GFS run. It was mentioned earlier from the email exchanges that too much variance (between the GFS and the other models? or the GFS and its ENS?) and it will be discarded.

Edited by Yarmy
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Posted
  • Location: Ripon , North Yorkshire 41m/135ft ASL
  • Weather Preferences: heat and cold, storms and blizzards...zonal a no no
  • Location: Ripon , North Yorkshire 41m/135ft ASL

yes yarmy i see what you mean, i dont think there has been any wild variances this year a strong negative result looks pretty much set in stone now, all the other models agree a -AO , So i assume its safe to say the GFS ( with variences) will keep it negative . 

 

To quote SM from page one

These legends are KEY to remember."

Junior AO months are winter months with an average index -1.0

Super AO months are Winter months with an average index -2.0

 

So if we have a final figure of -2.5  could that constitute  super duper AO:)

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Posted
  • Location: Portrush. (NI) UK
  • Location: Portrush. (NI) UK

That highlighted paragraph makes no sense regarding the current OPI? Have you messed up your copy and paste or are referring to another year. This years OPI hasn't gone positive yet so not sure how you come to that conclusion.

I've reworded my original post.

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Posted
  • Location: Currently Southminster, Essex (but original home town Northampton)
  • Weather Preferences: Heavy snow/Blizzards in Winter, Cool Summers. (I'm allergic to heat)!
  • Location: Currently Southminster, Essex (but original home town Northampton)

6z just updated... -2.80

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Posted
  • Location: Crewe, Cheshire
  • Weather Preferences: Snow, storms and other extremes
  • Location: Crewe, Cheshire

So if the index starts to settle between -2.5 and -3 the only real analogue we have for a sub -2.5 OPI and East based QBO is 2009/10

 

Not bad i suppose :wink:

I've mentioned '09/'10 as an analogue a couple of times based on ENSO and QBO. Looks like another factor MAY align also. A '09/'10 repeat would be top notch IMO.

 

I'll just add, I think it was a year the long range models had a nightmare over.

Edited by CreweCold
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Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL

 

I'll just add, I think it was a year the long range models had a nightmare over.

I'm not surprised, after all long range model forecasts are bound to favour westerly patterns in their programming. No way they would ever predict a three months of -AO and -NAO in October for Winter.

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Posted
  • Location: Weymouth, Dorset
  • Location: Weymouth, Dorset

WOW. I'm sure this must have already been posted but that is some jam for an AO forecast...

 

post-5114-0-84915200-1413822689_thumb.gi

 

Certainly looks like great news to me. I strongly suspect sharp dips in the AO value (and at times NAO) are going to be one the signature's of winter 14/15.

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Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth

Well this is weird...normally I get to this time of year having some kind of hunch about the winter to come - with limited success - and to be quite frank I think to myself I won't really know until a couple of weeks before time at very best.

But following this thread for the past week has kind of made me feel the winter forecast is done and dusted, going by a. the very clear direction of the OPI to extreme negative values and b. the equally unequivocal statistics presented here about what happens in an extremely negative year.

Surely ... after a lifetime, in fact many lifetimes, of painful attempts to forecast even 10 days out, and invariable failures by multimillion pound meteorological companies to even get individual months correct (sometimes 24 hours!) ... surely, it can't be quite so simple???

If this OPI leads to a collection of "super -AO weeks/months" this winter, and even just a few seriously below average temperature weeks here on our doorstep, surely it will be considered one of the greatest winter forecasts ever?

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Posted
  • Location: Brighton (currently)
  • Location: Brighton (currently)

What are people's thoughts on the 12z gfs? Low heights seem to gradually take control over the Arctic which is quite a change to what it was showing yesterday! Good job we are entering the final third of the month and we can be confident that the OPI will be negative.

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Posted
  • Location: Near King's Lynn 13.68m ASL
  • Weather Preferences: Hoar Frost, Snow, Misty Autumn mornings
  • Location: Near King's Lynn 13.68m ASL

What are people's thoughts on the 12z gfs? Low heights seem to gradually take control over the Arctic which is quite a change to what it was showing yesterday! Good job we are entering the final third of the month and we can be confident that the OPI will be negative.

 

Who knows? The GEM on the other hand has this:

 

gemnh-0-240.png?12

 

Just T240 isn't it. Too far out to take any of them seriously.

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Posted
  • Location: Brighton (currently)
  • Location: Brighton (currently)

Who knows? The GEM on the other hand has this:

 

gemnh-0-240.png?12

 

Just T240 isn't it. Too far out to take any of them seriously.

Yes, the GEM has generally been looking better for blocking! 

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Posted
  • Location: Ghent, Belgium
  • Location: Ghent, Belgium

It seems that this GFS oper has the least blocking if you compare with EC00z and GEM12z. Looking forward to EC12z.. Hopefully the OPI doesnt becomes more then -2.5.

Edited by Continental Arctic Front
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