Winter 2011/12 - General Discussion

[bluearmy]

I'm not entirely sure how accurate the IOD is, but it's forecasting below average temperatures for the UK and Europe between December-February, and much of the globe, having said that

http://www.jamstec.g...12.1oct2011.gif

can someone post a mean pressure anomoly chart that would lead to that pattern of warm eastern states/cool southern greenland, warm ne greenland/cold europe/warm scandi and siberia. now there is a challenge - must be possible as the mean chart is derived from 27 member runs.

[chionomaniac]

can someone post a mean pressure anomoly chart that would lead to that pattern of warm eastern states/cool southern greenland, warm ne greenland/cold europe/warm scandi and siberia. now there is a challenge - must be possible as the mean chart is derived from 27 member runs.

Funny that you should post this as I too was trying to work out what synoptic patterns would lead to the anomalies on the IO dipole chart. I know it is an average of all the months but the whole of the western Siberian Arctic is in a warm anomaly as is eastern Greenland. So that begs the question where is the cold that creates the UK anomaly going to come from? A little channel through Iceland by the looks of it.

Edit. Think about it further I suspect that there must be a wide divergence on the 27 member runs with a cluster at each end of the scale which gives the odd look to the anomaly chart. Perhaps we should be looking at the more confident warm anomalies and basing any mean pressure anomaly chart on them solely.

Edited October 15, 2011 by chionomaniac

[beng]

Funny that you should post this as I too was trying to work out what synoptic patterns would lead to the anomalies on the IO dipole chart. I know it is an average of all the months but the whole of the western Siberian Arctic is in a warm anomaly as is eastern Greenland. So that begs the question where is the cold that creates the UK anomaly going to come from? A little channel through Iceland by the looks of it.

Edit. Think about it further I suspect that there must be a wide divergence on the 27 member runs with a cluster at each end of the scale which gives the odd look to the anomaly chart. Perhaps we should be looking at the more confident warm anomalies and basing any mean pressure anomaly chart on them solely.

What about the charts for Feb 1991. Take a look at the 7th Feb 1991 - sorry couldn't resist a small winter ramp

Seriously it's strongly suggestive of Scandinavian blocking - not that that means it's going to be correct of course. It was similar last year, but went for a cold E US too if I remember correctly.

Edited October 15, 2011 by beng

[johnholmes]

can someone post a mean pressure anomoly chart that would lead to that pattern of warm eastern states/cool southern greenland, warm ne greenland/cold europe/warm scandi and siberia. now there is a challenge - must be possible as the mean chart is derived from 27 member runs.

I think there is something more than a bit odd about that chart. If you look at the IRI, Met O, and ECPC outputs for the same months they are nothing like that. It just seems highly unlikely that over a 3 month period so much of the globe would show what they are suggesting?

[beng]

I think there is something more than a bit odd about that chart. If you look at the IRI, Met O, and ECPC outputs for the same months they are nothing like that. It just seems highly unlikely that over a 3 month period so much of the globe would show what they are suggesting?

Yes a cold bias in the model maybe John? It was cold this time last year too, I don't know for sure how the winter land based surface temps averaged globally, but I don't think they were quite as cold as it predicted.

[DeepSnow]

Possible start of the mini-iceage? lol

There has to be something wrong there to show that much cold around the world? and be the only one showing it? Time will tell as ever, but like many I highly doubt that will happen!

Winter could show its first hand that its just around the corner this week, with parts of the U.K in with a chance of snow to lower levels in the far North and frost in the South East! Looking good

[Benvironment]

Winter could show its first hand that its just around the corner this week, with parts of the U.K in with a chance of snow to lower levels in the far North and frost in the South East! Looking good

I'd say winter has eleven hands. I just posted a blog piece about the 11 signs I look out for in the run up to winter:

http://benvironment.org.uk/post/11471937874/winterevents

At the moment they're happening along the same kind of timeline I'd expect in this part of the world. No frosts or subzero nights yet......but then the first subzero temperature here last year wasn't until 21st October, which also coincided with the first meaningful snowfall on the mountains. Wouldn't mind if they came earlier though!

[M1JWR]

As far as i am concerned, nature itself is a good indicator of the forthcoming season

i know a guy with a horse, the key is the thickness of its coat, it wasent wrong last year

This time last year it had a thick coat, and started to loose it last january after the cold

spell

This year its coat is nowhere as thick

what does that tell you all

[Backtrack]

Hmm. Tonight looks chilly. Could be the first widespread frost of the season if the cloud holds off.

Edited October 15, 2011 by Backtrack

[AWD]

As far as i am concerned, nature itself is a good indicator of the forthcoming season

i know a guy with a horse, the key is the thickness of its coat, it wasent wrong last year

This time last year it had a thick coat, and started to loose it last january after the cold spell

This year its coat is nowhere as thick

what does that tell you all

That the horse is going to be bl00dy cold in December??

[Isolated Frost]

M1JWR - nature is reactive, not proactive. Whatever happens now means nothing for the upcoming winter.

[summer blizzard]

It is official, on top of not ever reading Daily Mail articles i am now no longer going to read articles from the Express. They are beyond stupid.

[wimblettben]

Look, look, winter is here!

It's hardly going to be very noteworthy is it!

Some temperatures on or below freezing only on the highest parts of Scotland. Wow.

[A Winter's Tale]

The Daily Express article was just nonsense and so are simular articles by the Daily Mail (in particular) aswell as Daily Star and the Sun.

People you meet in the shop, street, school boast and gossip about how it's meant to snow at the end of the week and you know that newspapers such as the Express just play with people with an average meterological understanding by exaggerating on forecasts and publications.

What I've noticed this time round is that the articles this year seem more extreme. Another thing that is getting on my nerves is how they talk about that heatwave as if it was yesterday.

Anyway, looking towards next week should be interesting weather wise with strong winds, some rain about aswell as the potential for cold temperatures (i.e first 0c of the autumn) aswell as some hill snow in the highlands and perhaps to lower levels in places like Moray and Aberdeenshire. My feeling at the moment is that we will see Blocking from Greenland sometime between mid November and mid January and this should result in a cold spell (the duration and intensity of it of course would be uncertain). Even if the Greenland high doesn't pop up, the potential for shortlived cold spells is still alive and even in some of the milder and duller winters of 90s and 00s saw some decent snowfalls and cold spells. So when people say a winter is likely to be mild certainly doesn't rule out notable cold spells with snow and very rarely do we get a winter with very little snowfall (i.e at least we can expect some snow at some stage in a winter).

There is still 7 weeks till winter begins and we still have the potential/bonus for Northern Blocking to develop during November to bring another notable cold spell, however that woukd be a bonus and the earliest would like to see such synoptics would be at least in late November.

In conclusion, I feel relatively posisitive about this winter with the potential for not only smaller cold spells, but the greater prospect of the prominent feature that is the Greenland High which of course can bring severe winter weather for a sustained period and I believe that we have got November, December and January to look forward to for experiencing the Greenland High with a cracking start to the winter or looking out for it with decent developments during November and December (and don't write Febuary off).

[sebastiaan1973]

A nice forecast of the winter 2012.

http://www.lightinth...om/archives/420

E.g.

Putting it all together

The dominant factors at play for the winter of 2011-12 should be a weak geomagnetic field, weak electric field strength of the solar wind, a negative NAO, AO, PNA, PDO, and ENSO (moderate La Nina). In addition, a factor not mentioned in the discussion is the QBO, which measures variations in the equatorial stratospheric wind, will be near neutral to slightly negative. Data for winters with this modality in conjunction with the solar external forcing noted already support negative NAO winters with plentiful blocking. Notice that all the indices mentioned above will be in a negative state, suggesting that the middle latitudes of the northern hemisphere are in for a colder than normal winter overall. However, that does not mean everyone will be cold. Notable pockets of warmer than normal temperature departures will exist this winter, one such location over much of the Southern United States. Coupling the conditions expected with analogs (years with similar regimes to this one) suggest an overall warm winter (DJF) from the Southwestern US eastward through the central/southern Plains, and the Southeastern US. The DJF departure map for the Northeast of slightly below average temperatures is a bit deceiving, as I believe there will be periods of extreme cold and extreme warmth spattering the winter in the Northeast. The northern Rockies into the Mid-western US and Great Lakes should have a more predominately colder than average winter.

My analogs for this winter: 1954-55, 1955-56, and 2008-09.

Important for us -on the others ite of the Ocean- is in my opinion the predicted negative NAO.

Edited October 15, 2011 by sebastiaan1973

[Sprites]

Temp. dropped to 30f in the garden at 6am today, a slight frost on the car roof too, could be a re-run tonight.

[damianslaw]

A nice forecast of the winter 2012.

http://www.lightinth...om/archives/420

E.g.

Putting it all together

The dominant factors at play for the winter of 2011-12 should be a weak geomagnetic field, weak electric field strength of the solar wind, a negative NAO, AO, PNA, PDO, and ENSO (moderate La Nina). In addition, a factor not mentioned in the discussion is the QBO, which measures variations in the equatorial stratospheric wind, will be near neutral to slightly negative. Data for winters with this modality in conjunction with the solar external forcing noted already support negative NAO winters with plentiful blocking. Notice that all the indices mentioned above will be in a negative state, suggesting that the middle latitudes of the northern hemisphere are in for a colder than normal winter overall. However, that does not mean everyone will be cold. Notable pockets of warmer than normal temperature departures will exist this winter, one such location over much of the Southern United States. Coupling the conditions expected with analogs (years with similar regimes to this one) suggest an overall warm winter (DJF) from the Southwestern US eastward through the central/southern Plains, and the Southeastern US. The DJF departure map for the Northeast of slightly below average temperatures is a bit deceiving, as I believe there will be periods of extreme cold and extreme warmth spattering the winter in the Northeast. The northern Rockies into the Mid-western US and Great Lakes should have a more predominately colder than average winter.

My analogs for this winter: 1954-55, 1955-56, and 2008-09.

Important for us -on the others ite of the Ocean- is in my opinion the predicted negative NAO.

Interesting read. I would be happy with a winter similiar to 2008-2009 which also delivered a cold start especially for northern parts, the coldest start to Dec since 1978 - though things did unfortunatel become much milder in the run up to christmas. If we can see a winter very similiar to 08/09 but a bit colder, in my opinion I would end up rating it far higher than last year, but not quite as good as 09/10. My early inklings are for a colder version of 08/09 with cold snowy spells interespersed with shortlived milder wet atlantic outbreaks - but these are just my current thoughts and I won't be confirming them until much later in November. Also a Nov like 2008 would be good, no significant cold like last year but it was on the cool side with a notable cold frosty period mid-late month and a very cold end.

[vortex_liam]

I will say Thursday over the higher ground in Scotland could be interesting.

[Geordiesnow]

It's hardly going to be very noteworthy is it!

Some temperatures on or below freezing only on the highest parts of Scotland. Wow.

Looks like an Air frost in Northern parts of England too, city centre temps being around 3C potentially? Quite noticetably for October considering in recent times its been a mild month generally. Also it could be the first proper widespread frost of the season also so something to look forward too I suppose.

[Snowstorm1]

Bit chilly as you say Geordiesnow will certainly give me a cold head after my haircut today

[Summer Sun]

Currently 8.5°C in Darlington under clear sky's and no wind so a chilly night tonight for many yes.

Edited October 15, 2011 by Gavin D

[Met4Cast]

Incredibly cold 850hPa air being projected across Greenland next week

Astonishing!

[A Winter's Tale]

Incredibly cold 850hPa air being projected across Greenland next week

Astonishing!

I would imagine that would be quite good for us for the long term with such a decent cold pool over Greenland.

I see that you have found yourself on that [errr] "interesting" discussion of the Daily Mail site.

Edited October 15, 2011 by A Winter's Tale

[kold weather]

Actually not sure having very cold air over Greenland is a great thing, though at this stage its probably not super important either. In theory though a stronger thermal gradient is going to add to a greater chance of a strong jet and an organised PV, if we just take a basic view.

[summer blizzard]

A nice forecast of the winter 2012.

http://www.lightinth...om/archives/420

E.g.

Putting it all together

The dominant factors at play for the winter of 2011-12 should be a weak geomagnetic field, weak electric field strength of the solar wind, a negative NAO, AO, PNA, PDO, and ENSO (moderate La Nina). In addition, a factor not mentioned in the discussion is the QBO, which measures variations in the equatorial stratospheric wind, will be near neutral to slightly negative. Data for winters with this modality in conjunction with the solar external forcing noted already support negative NAO winters with plentiful blocking. Notice that all the indices mentioned above will be in a negative state, suggesting that the middle latitudes of the northern hemisphere are in for a colder than normal winter overall. However, that does not mean everyone will be cold. Notable pockets of warmer than normal temperature departures will exist this winter, one such location over much of the Southern United States. Coupling the conditions expected with analogs (years with similar regimes to this one) suggest an overall warm winter (DJF) from the Southwestern US eastward through the central/southern Plains, and the Southeastern US. The DJF departure map for the Northeast of slightly below average temperatures is a bit deceiving, as I believe there will be periods of extreme cold and extreme warmth spattering the winter in the Northeast. The northern Rockies into the Mid-western US and Great Lakes should have a more predominately colder than average winter.

My analogs for this winter: 1954-55, 1955-56, and 2008-09.

Important for us -on the others ite of the Ocean- is in my opinion the predicted negative NAO.

I highlighted the analogues at the bottom.

He is backing the PDO analogues as dominant minus 1954 which is an AO anologue.

Actually not sure having very cold air over Greenland is a great thing, though at this stage its probably not super important either. In theory though a stronger thermal gradient is going to add to a greater chance of a strong jet and an organised PV, if we just take a basic view.

I suppose it depends on how much of that cold air is poured out to the mid-latitudes (not much given that the coming high is mainly at the surface). As it is October though, i would actually prefer a strong cold pool.

Edited October 16, 2011 by summer blizzard