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Winter/Spring 2013 (Model Output Discussion)
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Just posted this in the Arctic thread, but for those not interested in the sea ice, I thought ye might still find this bit of interest.
The recent boom in snow cover across Eurasia is a very big positive for those wanting cold and snow this winter.
The "Snow Advanced Index" or the SAI, is a measure of the rate of increase in Eurasian October snow cover south of 60N and correlates extremely well with the AO in the following winter.
Having started the month off with such low snow cover, and having had quite a boom in recent weeks, the SAI index should be looking very good for a strongly -ve AO this winter.
Here's the paper, and the graph below showing the October SAI and Winter AO.
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Mark vogan isgoing for a mild nov decwith just small blasts of cold on the back arse of the low pressures ,
Correction, Vogan has posted the following comment on his Twitter account:
"Regarding the hype about cold/snow in November, yes it's very poss but until Dec it comes and goes I believe. Watch backsides of lows!".
So in reality he is saying an up and down or mild/cold November and is not saying anything about December. Those foolish enough can subscribe to this charlatan's website. He issues his full winter forecast on the 31/12/2012. In my opinion, his views are ropey to say the least.
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So how was the snow cover in 2010 october was it same as now or more,Just posted this in the Arctic thread, but for those not interested in the sea ice, I thought ye might still find this bit of interest.
The recent boom in snow cover across Eurasia is a very big positive for those wanting cold and snow this winter.
The "Snow Advanced Index" or the SAI, is a measure of the rate of increase in Eurasian October snow cover south of 60N and correlates extremely well with the AO in the following winter.
Having started the month off with such low snow cover, and having had quite a boom in recent weeks, the SAI index should be looking very good for a strongly -ve AO this winter.
Here's the paper, and the graph below showing the October SAI and Winter AO.0 -
So how was the snow cover in 2010 october was it same as now or more,
It's the rate of snow cover increase that counts. A week or two into November and the data should be available to compare with previous years.
You can download weekly Eurasian snow cover data here but it only goes up to week 39, which is the end of September.
This month did start off below average though, and we're now currently above average for Eurasia.
Early October (4th)
October 26th
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Wicklow Weather wrote: »Snowbies and cold lover will defo like this link to Will Coopers Weather Forecast "Winter 12/13" its UK based but an interesting read.
http://willcooperweather.weebly.com/uploads/1/0/8/3/10837558/long_range_forecast_winter_2012-13_full_report.pdf
Many thanks Wicklow Weather.
However lets be clear, this guy is a complete fantasist. He is calling for heavy snow throughout December, January and February for the UK. Very unlikely.
Its like he set down with his colouring pencils and markers so he could draw High Pressure over Greenland and Scandinavia with the Jet Stream then positioned well south of Britain & Ireland. AS IF!! I know this happened in December 2010 however the chances of it happening again are very low!!
Take this forecast seriously at your peril
Best rule of thumb is this when looking at the winter charts - go with the ECMWF model and only trust this 3-4 days out. If you see a major pool of cold air within that timeframe heading to Ireland from the North or the East, then we are most likely in business!
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Sponge Bob wrote: »Irrespective of whether one agrees or not he has collected a damn fine selection of osillations and with a note on the importance of each. Well worth a read for the noobs around here. A NINO is not an oscillation BTW
But El Nino is the positive phase of ENSO (El Nino Southern Oscillation)?0 -
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Deep Easterly wrote: »Not looking good for Ireland in that forecast as we are west of the much feared 'purple line'.
Aye, looks like cooler-than-average temperatures and wet muck for the foreseeable future.0 -
Wicklow Weather wrote: »Guys dont shoot the messenger thought his forecast was very well laid out. I dont buy into his forecast (Yet!) or any long range forecast for that matter, If its 10 days out or more I have little confidence in any forecast apart from looking at trends etc.
Fair points Wicklow Weather and I did say thank you for your post
You are correct in stating that anything over 10 days is long range. I would even say anything over 6/7 days is long range. Our little island is subject to four different influences which makes it very difficult to predict Ireland's weather - a westerly Atlantic influence, a northern polar, a southern tropical or a Siberian easterly.
Take your pick - my personal favourite is the Siberian Easterly
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cherryghost wrote: »Aye, looks like cooler-than-average temperatures and wet muck for the foreseeable future.
Met.no 3 month forecast for period November to January going for near to slightly warmer temps as a whole.
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Many thanks Wicklow Weather.
However lets be clear, this guy is a complete fantasist. He is calling for heavy snow throughout December, January and February for the UK. Very unlikely.
Its like he set down with his colouring pencils and markers so he could draw High Pressure over Greenland and Scandinavia with the Jet Stream then positioned well south of Britain & Ireland. AS IF!! I know this happened in December 2010 however the chances of it happening again are very low!!
Take this forecast seriously at your peril
Best rule of thumb is this when looking at the winter charts - go with the ECMWF model and only trust this 3-4 days out. If you see a major pool of cold air within that timeframe heading to Ireland from the North or the East, then we are most likely in business!
D
OK a bit of a climb down here
Had a brief look at Will Cooper's website to see what his winter prediction was for 2011/2012. I am very impressed! Here is his 2011/2012 UK winter summary....
A milder start to the Winter, with occasional colder spells, especially in December, North especially. January is expected to be mild throughout, until perhaps the closing days of the Month. February is likely to be the coldest month of Winter. December and Janaury will see a few storms, perhaps two or three major ones in Scotland and Northern UK. The Winter will be a two tale story, milder to start and colder to end.
Furthermore, he predicted a very mild Christmas (which materialized) with no chance of snow (correct!).
However, I have no proof that this is not a retrospective winter forecast, i.e. just posted in recent months (date on it is 1st December 2012)
However, if the post was issued last December 1st, then he was pretty accurate and we cold be in for a very cold 2012/2013!!
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I would not worry about the purple line, southern Ireland has a different color on his precipitation charts we don't even get an average:PDeep Easterly wrote: »Not looking good for Ireland in that forecast as we are west of the much feared 'purple line'.0 -
Wicklow Weather wrote: »Snowbies and cold lover will defo like this link to Will Coopers Weather Forecast "Winter 12/13" its UK based but an interesting read.
http://willcooperweather.weebly.com/uploads/1/0/8/3/10837558/long_range_forecast_winter_2012-13_full_report.pdf
Aaaaaaaaaahhhhh, at last, someone posts a link to someone who actually gives some detailed insight into how he's come around to his forecast. Fair play to that guy. Even if he's wrong at least he'll never be cast in the same basket as the Vogans of this world.
Good one, WW.
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But El Nino is the positive phase of ENSO (El Nino Southern Oscillation)?
You mean a Nino is a monopolar oscillation.
I recommended the document to less informed readers for its collection of oscillations and presentational style, very accessible and completist.
Noobs around here get their heads spun by constant references to AO NAO ENSO PDO AMO AMOC etc and need somewhere to start from and preferably with helpful graphics.
I reserved my view on it's overall conclusions....but good presentation is never to be sniffed at when a lot of the particular forecasters peers prefer to moan into webcams instead. 0 -
Had a brief look at Will Cooper's website to see what his winter prediction was for 2011/2012. I am very impressed! Here is his 2011/2012 UK winter summary....
Hmm, document created 19/10/2012 . I see what you mean.
http://willcooperweather.weebly.com/uploads/1/0/8/3/10837558/full_uk_winter_forecast_2011-12.pdf
I can find no google references to it before that date. He had another blog for about a week during the summer, FWIW. 0 -
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Sponge Bob wrote: »Hmm, document created 19/10/2012 . I see what you mean.
http://willcooperweather.weebly.com/uploads/1/0/8/3/10837558/full_uk_winter_forecast_2011-12.pdf
I can find no google references to it before that date. He had another blog for about a week during the summer, FWIW.
Thanks Sponge Bob - so my suspicions have been confirmed. He has issued a retrospective forecast for the 2011/2012 weather season, thus improving his kudos. Isn't hindsight a great thing?:D:D
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