Winter 2010/2011 Part 3

[damianslaw]

Another good winter of recent times i.e. 95/96 did see a cold december with some snow early on and the major freeze up during the last week - followed by a mild first half to Jan with cold easterlies during the last third and then a rather cold and in places very snowy feb leading into a notably cold March with further snow at times.

The difference however, between dec 95 and dec 10 was the depth and length of cold, in 95 the real cold occured in time for christmas. Winter 95/96 in many respects was very similiar to last winter with the cold lasting right through to the middle of March.

I do think very cold sustained weather before christmas is not a good omen for very cold sustained weather in jan and feb, however, I would say a shorter lived early cold snowy spell before christmas is quite a good omen for a largely cold winter in the main.

[Thundery wintry showers]

Here are the stats for winters with Decembers that were sub 1.5C CET since 1800:

1819/20: Dec 1.4, Jan -0.3, Feb 3.2

1829/30: Dec 1.4, Jan -0.2, Feb 2.2

1840/41: Dec 1.3, Jan 1.1, Feb 2.4

1844/45: Dec 0.4, Jan 3.2, Feb 0.9

1846/47: Dec 0.5, Jan 2.2, Feb 2.4

1853/54: Dec 1.3, Jan 3.6, Feb 4.3

1870/71: Dec 0.6, Jan 0.5, Feb 6.1

1874/75: Dec -0.2, Jan 6.4, Feb 2.3

1878/79: Dec -0.3, Jan -0.7, Feb 3.1

1879/80: Dec 0.7, Jan 0.9, Feb 5.8

1890/91: Dec -0.8, Jan 1.3, Feb 3.9

1950/51: Dec 1.2, Jan 3.9, Feb 3.7

1981/82: Dec 0.3, Jan 2.6, Feb 4.8

Severe Decembers have been very rare indeed during the twentieth century, so we need to go back to the 1800s to get a clearer idea of how the weather has traditionally behaved following severe Decembers in the past. If anything there is a tendency for cold weather in December to persist during the following January as well, with milder conditions more commonplace into February. It's interesting that the 1890/91 instance that I've quoted a lot recently, which featured this pattern to some extent, didn't actually have a particularly mild February by measure of the CET- presumably a case of warm days offset by cold nights.

In any case the statistics do not bear out the popular view that a prolonged severe spell pre-Christmas puts the kabosh on the rest of the winter.

[Alex95]

The thing that worried me back in Dec like others was maybe that would b our winter and we would not get such cold and snow again for the remainder,but i never expected it to be so snowless the way it has been since then. I would have liked the winter to have been spread out more but i love Dec because i love xmas and this yr it certainly was very festive to say the least. Xmas eve and xmas day were my perfect winter days,very cold,a heavy blanket of snow and clear skies.

The weather has been disappointing since xmas but i would IMO still rate this winter a success rather then a failure for cold lovers because Dec was such an epic month. I feel though that many will not see this winter as a success if we dont get some sort of a cold spell again before the winter is over and of course we are running out of time now but you never know what might happen between now and the end.

It depends where you live really. I got 40cm at the end of November with the best thundersnow I've ever seen, with snow lying for over 2 weeks, then after a more average third week the cold returned in time to give 10cm for Christmas and bitterly cold temperatures. That's a success in my book! A battleground situation later on this week would put the icing on the cake.

[lukemc]

Hi,

Talking of this winter being an exceptional December (and late November) for snow and cold and then becoming poor or unexceptional for cold and snow for much of the rest of the winter, what do you think has caused the rest of the winter to go "pear shaped" as some put it? Top of my mind would be the strong La Nina - but even that does not explain all e.g. it does not seem to apply in some other parts of the Northern Hemisphere - e.g. I just saw a report on CNN today about an unusually snowy spell of weather in the Korean peninsula (including Seoul) so the strong La Nina does not seem to be stopping snow and cold in some other parts of the world this month!

Anyway if we consider the strong La Nina to be at least partially to blame for the disappearence of the synoptics conductive for cold and snow, does anyone think that if it wasn't for the strong La Nina (e.g. if we had an ENSO close to neutral) we could have been looking at a true classic winter on the scale of 1947-48, 1962-63 or at least 1978-79?

Luke

[Weather-history]

Severe cold developing early in the winter rarely sustains itself simply because sustained cold is very hard to achieve full stop.

Very true.

Its the same with sustained intense heat. Look at July 2006, it did not carry on into the August.

[North-Easterly Blast]

Very true.

Its the same with sustained intense heat. Look at July 2006, it did not carry on into the August.

Off the winter topic I know, but Summer 2006 was indeed a rare pattern, although the summer of 1921 was similar. July 1921 was very warm (18.5), but August was a much cooler month at 15.4 CET. I have to say that the statistical norm is, after a very warm July, for an August that is less warm but still with a good deal of warm weather around a la Summer 1983, 1976 etc.

Summer 2006 actually only featured a break in August with a much more average month, then it went on to produce a record warm September.

I certainly feel that cold setting in later in December has much more staying power than a deep freeze up setting in during late Nov / early Dec, like 1962-63, 1978-79 etc. 1939-40 was also similar too. 1894-95 also saw at the very back end of December the cold setting in. 2009-10 didn't doo bad either, cold set in in mid-December rather than late in the month, and whilst the peak was over by mid-January, Feb 2010 was still a generally cold month with snow for some and there were limited mild spells.

[Thundery wintry showers]

Again I don't think the above stats really bear that out. Many of the excessively cold Decembers of the 1800s (which must have had cold weather set in long before Christmas, or else such low CETs would be impossible) actually led into very cold Januarys, but without exception all of them were followed by a milder February.

The general gist of the stats is that more than two consecutive months of exceptional cold is very rare. For instance 1962/63 had the severe cold concentrated between 26 December and the last week of February while 1946/47 had the severe cold set in around 20-23 January and persist through to mid to late March- in both case about two months' worth. There is a greater tendency for cold spells to be persistent during February than earlier in the season due to the Atlantic traditionally slowing down a touch, but the evidence doesn't really support the notion of a similar difference between cold setting in early or late during December.

[Weather-history]

Off the winter topic I know, but Summer 2006 was indeed a rare pattern, although the summer of 1921 was similar. July 1921 was very warm (18.5), but August was a much cooler month at 15.4 CET. I have to say that the statistical norm is, after a very warm July, for an August that is less warm but still with a good deal of warm weather around a la Summer 1983, 1976 etc.

If you look at all the Julys that were 18.0C and over (25 in total), only 6 were followed by an August of 17.0 or greater and 10 were followed by an August of less than 16.0C.

You quoted 1976 and 1983, they were 2 out of the 6 Julys that were then followed by an August of 17.0C or greater. Pre 1976, there were only 3

The figures don't quite support your point.

[knocker]

At the risk of being boring a quick look again at the exceptional mild weather experienced in Canada during the winter using Coral Harbour as an example.

In Coral Harbour, a high of 3.3°C in mid-December broke the old record of 1.7°C set in 1963. The daily minimum temperature on January 6, 2011, was about 30°C warmer than normal. For much more detail on this and interesting comment on the extreme 500mb height anomaly.

http://www2.ucar.edu...ashing-mildness

Edited February 13, 2011 by weather ship

[damianslaw]

Here are the stats for winters with Decembers that were sub 1.5C CET since 1800:

1819/20: Dec 1.4, Jan -0.3, Feb 3.2

1829/30: Dec 1.4, Jan -0.2, Feb 2.2

1840/41: Dec 1.3, Jan 1.1, Feb 2.4

1844/45: Dec 0.4, Jan 3.2, Feb 0.9

1846/47: Dec 0.5, Jan 2.2, Feb 2.4

1853/54: Dec 1.3, Jan 3.6, Feb 4.3

1870/71: Dec 0.6, Jan 0.5, Feb 6.1

1874/75: Dec -0.2, Jan 6.4, Feb 2.3

1878/79: Dec -0.3, Jan -0.7, Feb 3.1

1879/80: Dec 0.7, Jan 0.9, Feb 5.8

1890/91: Dec -0.8, Jan 1.3, Feb 3.9

1950/51: Dec 1.2, Jan 3.9, Feb 3.7

1981/82: Dec 0.3, Jan 2.6, Feb 4.8

Severe Decembers have been very rare indeed during the twentieth century, so we need to go back to the 1800s to get a clearer idea of how the weather has traditionally behaved following severe Decembers in the past. If anything there is a tendency for cold weather in December to persist during the following January as well, with milder conditions more commonplace into February. It's interesting that the 1890/91 instance that I've quoted a lot recently, which featured this pattern to some extent, didn't actually have a particularly mild February by measure of the CET- presumably a case of warm days offset by cold nights.

In any case the statistics do not bear out the popular view that a prolonged severe spell pre-Christmas puts the kabosh on the rest of the winter.

Agreed, but they do show an equally cold late winter has not statistically occured. All those winters apart from 1845 saw Febs above 2 degrees - whilst still a cold value, nothing exceptional. I stand by the assertion a very cold sustained spell of weather before christmas will more likely than not result in a not particularly severe Feb.

[North-Easterly Blast]

Here are the stats for winters with Decembers that were sub 1.5C CET since 1800:

1819/20: Dec 1.4, Jan -0.3, Feb 3.2

1829/30: Dec 1.4, Jan -0.2, Feb 2.2

1840/41: Dec 1.3, Jan 1.1, Feb 2.4

1844/45: Dec 0.4, Jan 3.2, Feb 0.9

1846/47: Dec 0.5, Jan 2.2, Feb 2.4

1853/54: Dec 1.3, Jan 3.6, Feb 4.3

1870/71: Dec 0.6, Jan 0.5, Feb 6.1

1874/75: Dec -0.2, Jan 6.4, Feb 2.3

1878/79: Dec -0.3, Jan -0.7, Feb 3.1

1879/80: Dec 0.7, Jan 0.9, Feb 5.8

1890/91: Dec -0.8, Jan 1.3, Feb 3.9

1950/51: Dec 1.2, Jan 3.9, Feb 3.7

1981/82: Dec 0.3, Jan 2.6, Feb 4.8

Severe Decembers have been very rare indeed during the twentieth century, so we need to go back to the 1800s to get a clearer idea of how the weather has traditionally behaved following severe Decembers in the past. If anything there is a tendency for cold weather in December to persist during the following January as well, with milder conditions more commonplace into February. It's interesting that the 1890/91 instance that I've quoted a lot recently, which featured this pattern to some extent, didn't actually have a particularly mild February by measure of the CET- presumably a case of warm days offset by cold nights.

In any case the statistics do not bear out the popular view that a prolonged severe spell pre-Christmas puts the kabosh on the rest of the winter.

Certainly those statistics do show that quite often after a very cold December, the cold weather does continue into the rest of the winter, albeit on a less persistent and lower level case, although in some cases a similar level of deep cold has continued into the January. I certainly cannot see a winter in the records that has seen such extreme early cold pre-Xmas that has dissappeared abruptly for good even before December is out like in 2010-11.

I certainly feel that in any future year from now if serious cold of anything approaching a pre Xmas 2010 type does develop in late November / early December there will be frequent posts quoting 2010-11 as the year early serious cold quickly deteriorated into nothing by the turn of Xmas and a number of people will be writing off all of the post Xmas winter period. This may well continue decades ahead when many of us present forum users are no longer with us and new users come along and look at records seeing how pear shaped this winter was, how serious early cold dissappered completely and so abruptly quickly deteriroated into nothing by late December in 2010-11.

Edited February 13, 2011 by North-Easterly Blast

[knocker]

At the risk of being boring a quick look again at the exceptional mild weather experienced in Canada during the winter using Coral Harbour as an example.

In Coral Harbour, a high of 3.3°C in mid-December broke the old record of 1.7°C set in 1963. The daily minimum temperature on January 6, 2011, was about 30°C warmer than normal. For much more detail on this and interesting comment on the extreme 500mb height anomaly.

http://www2.ucar.edu...ashing-mildness

It might be of interest, or of course it might not, but the temp at Coral Harbour at 1800z was -15F.

[A Winter's Tale]

If things develop in the right direction in the Models, hopefully a potent cold snap will round this winter off. I am content enough with having the best of the winter cramed into the end of November and most of December. I prefer to have cold weather in December because I tend to look forward to wintry weather around Christmas and it looks and feels its best during December when the nights draw in. I would have liked to have experienced two or three decent cold spells in and around January and February. Prior to the winter 2008/2009 and post 2005/2006 there were very little decent snowfalls. In January we had a spell where we had more lying snow than some of the dull winters in the last 8 years.

[North-Easterly Blast]

I had thought of those too Kevin, but although those Decembers were pretty cold, none of those that you mention were anything like as cold as Dec 2010, so yes they did go pear shaped, but it wasn't as large a swing as this winter has turned out to be.

Whilst I thought that winter 1996-97 went pear shaped, certainly winters 1917-18, 1925-26, and 1927-28 are in the same league as 1996-97 in terms of the level of a pear shaped winter, but none of these match 2010-11, as the earlier levels of cold were nothing like what we saw pre Xmas 2010.

[Thundery wintry showers]

Agreed, but they do show an equally cold late winter has not statistically occured. All those winters apart from 1845 saw Febs above 2 degrees - whilst still a cold value, nothing exceptional. I stand by the assertion a very cold sustained spell of weather before christmas will more likely than not result in a not particularly severe Feb.

I can't argue with that particular assertion- the statistics strongly bear that one out!

I certainly feel that in any future year from now if serious cold of anything approaching a pre Xmas 2010 type does develop in late November / early December there will be frequent posts quoting 2010-11 as the year early serious cold quickly deteriorated into nothing by the turn of Xmas and a number of people will be writing off all of the post Xmas winter period. This may well continue decades ahead when many of us present forum users are no longer with us and new users come along and look at records seeing how pear shaped this winter was, how serious early cold dissappered completely and so abruptly quickly deteriroated into nothing by late December in 2010-11.

I have a feeling you may be right- considering that we had a lot of references to the "November, ice & ducks" saying this year, with only a fairly tenuous link with 1981/82 and some folklore supporting it, I think there's a good chance of it being emphasised more strongly in future years.

[Weather-history]

If this February beats this mild threshold then winter 2010-11 will surely beat 1944-45 and go down as THE MOST PEAR SHAPED WINTER EVER!

I could argue that if you are going to have a pear-shaped winter, better to have the cold as cold as possible. This could be argued as the best of the pear-shaped winters as what cold came, it was severe and intense. Not like 1996-97 and 2001-02 where the cold was not especially intense

Edited February 14, 2011 by Mr_Data

[North-Easterly Blast]

I could argue that if you are going to have a pear-shaped winter, better to have the cold as cold as possible. This could be argued as the best of the pear-shaped winters as what cold came, it was severe and intense. Not like 1996-97 and 2001-02 where the cold was not especially intense

What I mean is that this winter far exceeds 1996-97 as a pear shaped winter, as Dec 1996 was nowhere near as cold as Dec 2010, and in that winter the main cold period was late Dec until Jan 10th. 2001-02 is a similar pattern to 96-97, although still doesen't quite fit 96-97, as no cold that winter was especially cold at all, just a few deep frosts around the turn of the year.

Certainly as you mention winters 1917-18, 1925-26 and 1927-28 were in a very similar league to 1996-97 and all had some decent cold spells early on and deteriorated into mild rubbish by mid-point or even in early Jan in 1928. Although on top of this, 2010-11 far exceeds all of these as a pear shaped winter, and faded away into rubbish on a much larger swing, and even before December was out, none of those other four went belly up so early, and 2010-11 certainly must go down as THE most pear shaped winter since records began.

I have just checked the CET record, and found that no winter containing a sub zero month finished above 3.0 overall for the season. The mildest winters ever to contain a sub zero month were 1955-56 and 1985-86, both of which ended at 2.9 overall. So, if this Feb is 6.0 or higher then it will break any other pear shaped winter by a long way.

[Evening thunder]

It sounds like you would have preferred December not to have been nearly as cold?

For me It was the best cold spell/period I have seen in this country. Slow lying 13 days, beautiful snowy and sunny scenes, A max depth of nearly a foot (!) on low ground 4 miles from the sea in Devon, lasting until after Christmas. Min temp of -14C on Xmas day. I thought I was quite lucky with January.

I agree it could be a huge and interesting contrast between December and February, Though of course I'm glad we got the December we did.

[Thundery wintry showers]

I could argue that if you are going to have a pear-shaped winter, better to have the cold as cold as possible. This could be argued as the best of the pear-shaped winters as what cold came, it was severe and intense. Not like 1996-97 and 2001-02 where the cold was not especially intense

In addition it could also be argued that the teleconnections & La Nina anologues favoured mild and largely snow free conditions to take over during mid to late winter, and so from that perspective, best to extract as much as possible out of December before the signals for a mild mid to late winter kick in (indeed I recall Glacier Point and other teleconnections specialists making comments along those lines). With the exception of only limited areas of the UK, I think we very emphatically did!

[North-Easterly Blast]

In addition it could also be argued that the teleconnections & La Nina anologues favoured mild and largely snow free conditions to take over during mid to late winter, and so from that perspective, best to extract as much as possible out of December before the signals for a mild mid to late winter kick in (indeed I recall Glacier Point and other teleconnections specialists making comments along those lines). With the exception of only limited areas of the UK, I think we very emphatically did!

Although certainly going back to 1950 no La Nina that was as intense as this year produced a December anything like what we got - and no December in a similar La Nina winter was cool let alone cold. Dec 1950 was a cold one but that year's La Nina was less intense than the one this winter.

I would much have preferred something like 2009-10 or 1995-96 with the cold spread out over the winter season as a whole, not to start well and dissappear completely into nothingness and such an awful Feb. It's like seeing great looking cold charts at +168, +144 or even as low as +120 for reality to be far from what the charts show. I really hope I never have to endure something like this winter again. Something like many winters in the 90s and 2000s that were devoid of anything worthwhile full stop was so dissappointing to work my way through, but 2010-11 has still been dissappointing in its own way - a bit like the likes of 1996-97, and further back what 1917-18, 1925-26 and 1927-28 would have seemed like although on a much larger scale.

Something like the mid 1980s, 1990-91, 2009-10, 1995-96 or even 2008-09 is far better than this winter. Even 1981-82 wasn't quite as bad as this year. A fairly cold but quite peculiar winter is 1968-69, with some great cold spells but a mild January in between, but still this winter wasn't anything like 2010-11.

Will we ever see a neutral ENSO winter again?

Personally I would put my preference like this in order:

Neutral

Weak La Nina

Weak El Nino

Moderate El Nino

Moderate El Nino

Strong El Nino

Strong La Nina

Strong La Ninas are the kiss of death for winter in the UK. Neutral is the best bet, although still is no guarantee of colder winter conditions in the UK. A number of Weak La Ninas and El Ninos have also seen good winter cold spells. Strong La Ninas often have been poor, although a pretty strong one did co-incide with last winter, and also a fairly cold and snowy month in Feb 1983. It seems with a strong La Nina there is no chance of the winter not being dissappointing in all respects or at least in some way or another like this year.

I am now wondering if we can ever see a winter that has a decently mild December followed by colder conditions in Jan/Feb, like the mid 1950s or mid 1980s. Anything remotely approaching this pattern seems to have completely dissappeared from our weather in recent years.

I certainly now feel that many will consider serious early winter cold as a kiss of death for the post Xmas winter period. I always feared that the cold developed far too early this winter for it to turn into anything worthwhile of a winter and would more than likely end up dissappointing for the most part in the end.

Edited February 14, 2011 by North-Easterly Blast

[Snowyowl9]

Even 1981-82 wasn't quite as bad as this year.

Thats the understatement of the year with what January gave almost 2ft of snow and one of the most severe blizzard wales has seen.

http://www.wetterzentrale.de/archive/ra/1982/Rrea00119820108.gif

http://www.wetterzentrale.de/archive/ra/1982/Rrea00119820110.gif

Last november/december did give more snow to december 1981 in total here.

But overall give me 1981-82 winter anyday that will and always will be a classic.

And there would be an outstanding thunderstorm june to look towards aswell.

[cheeky_monkey]

Hi,

Talking of this winter being an exceptional December (and late November) for snow and cold and then becoming poor or unexceptional for cold and snow for much of the rest of the winter, what do you think has caused the rest of the winter to go "pear shaped" as some put it? Top of my mind would be the strong La Nina - but even that does not explain all e.g. it does not seem to apply in some other parts of the Northern Hemisphere - e.g. I just saw a report on CNN today about an unusually snowy spell of weather in the Korean peninsula (including Seoul) so the strong La Nina does not seem to be stopping snow and cold in some other parts of the world this month!

It can be cold and snowy everywhere in the Northern hemisphere at the same time..when it is cold in one location it will be mild in another. When it was very cold across western europe and the uk it was very warm in eastern canada and greenland..now it has flipped back the other way its just the way it is.

[virtualsphere]

While it's a shame Jan and Feb have been disappointing for wintry weather, I still think this has been a cracking winter overall thanks to the exceptional spell before Christmas. If December and February were reversed, and December had a CET of around say 6.5C and February a subzero CET, the overall outcome for winter would be the same even though winter would end on a more positive note. Personally I'd rather take the subzero month in December when the days are a bit shorter and the festive season is in full swing, but I can appreciate some may prefer the reverse especially given easterlies have the potential to be more potent in January or early February.

The negative side is that, unless something exceptional happens in the next four weeks that the teleconnections don't support, we'll probably have to wait until at least next December for another cold spell. In a few months time I think this winter may be seen in a more positive light as a classic winter which produced the first subzero month since 1986, the coldest December since 1890 and nearly the coldest on record, and a remarkably cold end to November to boot with severe weather on the news before winter had even officially begun.

I've been particularly impressed by Glacier Point's long range forecast this winter too, which I notice was issued as long ago as 18th October and predicted December would be the coldest month of the winter, and was remarkably accurate with the general pressure patterns for Dec / Jan. Good call - and another reason why NetWeather is the best site to visit during the winter season!

[Glacier Point]

Although certainly going back to 1950 no La Nina that was as intense as this year produced a December anything like what we got - and no December in a similar La Nina winter was cool let alone cold. Dec 1950 was a cold one but that year's La Nina was less intense than the one this winter.

Will we ever see a neutral ENSO winter again?

Strong La Ninas are the kiss of death for winter in the UK. Neutral is the best bet, although still is no guarantee of colder winter conditions in the UK. A number of Weak La Ninas and El Ninos have also seen good winter cold spells. Strong La Ninas often have been poor, although a pretty strong one did co-incide with last winter, and also a fairly cold and snowy month in Feb 1983. It seems with a strong La Nina there is no chance of the winter not being dissappointing in all respects or at least in some way or another like this year.

The key thing to understand with La Ninas in November and December is that they will actively support whatever the dominant signal is going into the winter. However, turn the year and they actively destroy any -NAO / -AO signal. This year I've been very impressed with the robustness of the -NAO inspite of this strong Nina, which can only auger well going forward into next winter.

My list of favoured ENSO states for a cold winter would be:

Strong El Nino

Moderate El Nino

Weak El Nino

(get the gist here?)

Neutral

Weak / moderate Nina

Strong Nina

I cannot stress enough though that our definition of Nina / Nino must be in terms of the atmospheric response such as the Multivariant ENSO Index and GLAAM.

[North-Easterly Blast]

While it's a shame Jan and Feb have been disappointing for wintry weather, I still think this has been a cracking winter overall thanks to the exceptional spell before Christmas. If December and February were reversed, and December had a CET of around say 6.5C and February a subzero CET, the overall outcome for winter would be the same even though winter would end on a more positive note. Personally I'd rather take the subzero month in December when the days are a bit shorter and the festive season is in full swing, but I can appreciate some may prefer the reverse especially given easterlies have the potential to be more potent in January or early February.

The negative side is that, unless something exceptional happens in the next four weeks that the teleconnections don't support, we'll probably have to wait until at least next December for another cold spell. In a few months time I think this winter may be seen in a more positive light as a classic winter which produced the first subzero month since 1986, the coldest December since 1890 and nearly the coldest on record, and a remarkably cold end to November to boot with severe weather on the news before winter had even officially begun.

I've been particularly impressed by Glacier Point's long range forecast this winter too, which I notice was issued as long ago as 18th October and predicted December would be the coldest month of the winter, and was remarkably accurate with the general pressure patterns for Dec / Jan. Good call - and another reason why NetWeather is the best site to visit during the winter season!

The winter of 1985-86 wasn't severe overall. It had a CET of 2.9, but had a mild December and a very cold February. However, whilst the centerpiece of that winter was from late Jan through to early March, the winter wasn't devoid of cold weather up until then. After persistently very mild weather up to Xmas 1985, a cold spell arrived by Boxing Day that year and it stayed cold until Jan 9th 1986, and a number of places saw some snowfall early January, before a milder period over mid Jan 1986 before the real cold arrived.

The winter of 1981-82 is often quoted as a pear shaped winter with extreme cold dissappearing by mid-January, and February that year being poor. I will point out to you that whilst February 1982 was largely dominated by mild southerlies with a block over Europe, it did actually become colder for a time after mid-month, and despite the overall CET of 4.8 for that month, the period 15th to 24th was 1.7. So after mid January yes it was largely mild, but something colder did put in an appearance from the 15th to 24th Feb. Feb 1982 had a CET of 4.8, but it was still less of a swing of a pear shaped winter than looks likely for this month and this winter.

A winter has got to be far from a cracking winter or a classic if it has an exceptional cold spell alongside two thirds of the winter seeing next to nothing and a prolonged spell of mild weather in another month, surely it is more of a case of a winter having an exceptional cold spell with the rest of it not special or even poor.

Definitely winter 2009-10 is certainly considered a cracking winter, and certainly the best since at least the mid 1980s, with a prolonged cold spell from mid-Dec to mid-January and a colder than average February too, and cold spread throughout most of the winter even persisting up until mid-March, and very little of that winter saw significant mild or otherwise next to nothing. Winter 2008-09 although not especially cold still had cold spells frequently occurring through the winter and it was mid-Feb before it faded away.

I would definitely put winter 2010-11 as the most pear shaped winter in UK weather history; a more extreme version of the other pear shaped winters of 1996-97, 1927-28, 1925-26 and 1917-18, which quickly deteriorated into rubbish after early cold spells on a lesser scale than Dec 2010. Whilst 1962-63 may be among the most famously cold winters ever, surely winter 2010-11 is as pear shaped on an equally extreme level if not more so than 1962-63 was in terms of sustained cold.

I would love a 2009-10, 1995-96, 1990-91, mid 1980s type winter any day, and would not mind even something like 2008-09 or even an average winter that has cold spells spread throughout the winter. I certainly cannot stand a winter that promises so much at the start only to deteriorate into nothing and dissappear completely before you have even got Xmas out of the way, leaving the rest of winter like many of the rubbish Jans / Febs we endured through the 90s and 2000s.

I am dissappointed in winters that fall into any of these three categories:

Winters such as 88-89, 89-90, 97-98, 98-99, 99-00, 2001-02, 2006-07, 2007-08 are dissappointing in the way that they were mild throughout the whole winter, or otherwise had exceptional and / or prolonged mild spells, a la Jan / Feb 2002, Jan 2008 etc.

Winters like 1991-92, 1992-93 are dissappointing in the way that although not especially mild, saw a mid-latitude block sat over the UK most of the winter with no interest whatsoever in the weather pattern and hardly any snow. I do not know of any other winters that fell into the 91-92, 92-93 league.

Winters like 1996-97, 1917-18, 1925-26, 1927-28, 1937-38 and especially 2010-11 that promise so much at the start to be a good winter or even a classic that quickly deteriorate into rubbish or nothing is just so dissappointing to have all the good taken away.

Even if a winter is not severe or a classic overall I will still be satisfied if the winter does not fall into any of the above three categories.

The key thing to understand with La Ninas in November and December is that they will actively support whatever the dominant signal is going into the winter. However, turn the year and they actively destroy any -NAO / -AO signal. This year I've been very impressed with the robustness of the -NAO inspite of this strong Nina, which can only auger well going forward into next winter.

My list of favoured ENSO states for a cold winter would be:

Strong El Nino

Moderate El Nino

Weak El Nino

(get the gist here?)

Neutral

Weak / moderate Nina

Strong Nina

I cannot stress enough though that our definition of Nina / Nino must be in terms of the atmospheric response such as the Multivariant ENSO Index and GLAAM.

A Strong El Nino can't be the best bet - of all strong El Ninos since 1950 only in 2009-10 did one co-incide with a cold winter, although one other did co-incide with a fairly cold and snowy month (Feb 1983). I don't think that this year's pear shaped winter can be wholly blamed on La Nina, winter 1996-97 was neutral and that still quickly deteriorated into nothing. However, some weak to moderate La Ninas have given a decent winter, like 1995-96, 1984-85, 1985-86 etc. Even 1962-63 was a weak La Nina.