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noggin

Winter 2007/2008

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Hope this is OK for a new topic here! :help:

I have seen people talking about Spring and Summer charts being interesting not only for Spring and Summer but also because they show conditions which can build and perhaps give a good indicator of what could happen later in the year.

As I don't like the hot weather but enjoy coming onto the site, I would be grateful if anyone could indicate the sorts of things that it is proper to look for during Spring and Summer which could give an indication of where the Winter may be heading.

A bit like the Meto experimental seasonal forecasts......what sort of things should we look out for?

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A miracle and a massive Volcanic eruption :help: .

Seriously though we need to lose these indian summers in Sep/oct for starters.

I shall post more later when I have the time.

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i think TEITS is right - in conjunction with a likely La Nina, a big eruption mid to late summer (no deaths of course) in the NH would really help.

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A miracle and a massive Volcanic eruption :help: .

Seriously though we need to lose these indian summers in Sep/oct for starters.

I shall post more later when I have the time.

We certainly need to lose the Indian Summers particularly in September IMO. Not such a bad thing to get an Indian Summer during October so long as it remains dry, with a colder November to follow.

It just goes to show how poor this Winter has been when talk about the following Winter starts before this Winter's even over!

:lol:

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How about we get through spring and summer before worrying about next winter!! There is plenty of weather to enjoy at other times of the year you know!

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How about we get through spring and summer before worrying about next winter!! There is plenty of weather to enjoy at other times of the year you know!

As long as it's mild, warm, hot or very hot!

:help:

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winter 07-08 atlantic dominated. probably milder than this winter with no cold spells most likely :wallbash:

yeah as long as the summer is warm sunny with lots of thunderstorms, and not just dull damp and boring

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Okay, this is probably a good thread to monitor developments for the next year.

I have had a look at the MEI, AO, QBO and PDO data and this is what i came up with...

The anologues are equally spread with three going for anywhere between neutral and a moderate La Nina, and the other three going for neutral to a moderate El Nino, my personal opinion is that we will see a weak La Nina next winter.

These anologues are spread with one group going for a neutral QBO next winter, and the other going for a moderate easterly QBO next winter, i would favour the moderate easterly QBO for next winter.

The anologues are again spread, but the majority go for a neutral to negative PDO, i would concur with this, given recent trends.

There are very few AO anologues for the January AO, though they point to a negative AO winter.

Given these factors, i would call for a very northerly winterly with the main blocking being over Greenland as opposed to Scandinavia, with all three months below average, though i expect December to be the coldest month relative to average followed by February, and then January, i also expect January to be the wettest/snowiest month relative to average with December the driest, though January also has the biggest potential for easterly weather types in my opinion.

Generally, for a cold winter, we need the following factors...

1) Negative AO

2) Easterly QBO

3) Neutral or weak MEI values

4) Negative or positive PDO, not close to neutral

A miracle and a massive Volcanic eruption :wallbash: .

Seriously though we need to lose these indian summers in Sep/oct for starters.

I shall post more later when I have the time.

I agree with both points, a major eruption is needed, i also agree that we need to lose the Autumn warmth.

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The main point is that while most Septembers since 1997 have been warm the vast majority of winters that have followed a warm September have turned out to be mild especially in the modern day, so I think it is a well known fact now of the British Climate that a warm September will almost always lead to a mild winter. Most Octobers since 1997 have shown the repetitive pattern of being warm and wet, or average and wet.

We really need to see a cool wet September followed by a warm dry October; we have not had this since 1995 and not a cold winter since 1995-96. We also need the SSTs to cool in the north Atlantic especially near Greenland and Iceland, no El Nino, and no repeat of the stratospheric cooling of last autumn. With two of these downside factors for a cold winter being present last September and with the month turning out to be very warm I made the earliest "winter is over" post worded as "this warm September will be really nailing the coffin for a cold winter, the SSTs have not changed since last year and previous years, we have an El Nino, and the warm September = mild winter theory. If September's weather patterns continue to show the same repetitive warm pattern year after year, then why should the winter patterns change?"

Between now and September, we need to be looking for a change in the SST pattern, and we need to see some months with below average CETs. If month after month until November this year continues to record temperatures above the benchmark CET average, then how can a cold winter be realistically expected. I would say that around three of the next nine months need a below average CET before anyone can start talking about a cold winter for 2007-08, or any future year.

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Summer Blizzard;

Oh no, do not say that there is another El Nino on the way for next winter? We have just had one ever since the summer and it has only just faded away over this month of February. It has wrecked this winter by contributing to the strongly positive AO across the northern hemisphere with the stratospheric cooling event in November. An El Nino also wrecked the 1997-98 winter.

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The main point is that while most Septembers since 1997 have been warm the vast majority of winters that have followed a warm September have turned out to be mild especially in the modern day, so I think it is a well known fact now of the British Climate that a warm September will almost always lead to a mild winter. Most Octobers since 1997 have shown the repetitive pattern of being warm and wet, or average and wet.

We really need to see a cool wet September followed by a warm dry October; we have not had this since 1995 and not a cold winter since 1995-96. We also need the SSTs to cool in the north Atlantic especially near Greenland and Iceland, no El Nino, and no repeat of the stratospheric cooling of last autumn. With two of these downside factors for a cold winter being present last September and with the month turning out to be very warm I made the earliest "winter is over" post worded as "this warm September will be really nailing the coffin for a cold winter, the SSTs have not changed since last year and previous years, we have an El Nino, and the warm September = mild winter theory. If September's weather patterns continue to show the same repetitive warm pattern year after year, then why should the winter patterns change?"

Between now and September, we need to be looking for a change in the SST pattern, and we need to see some months with below average CETs. If month after month until November this year continues to record temperatures above the benchmark CET average, then how can a cold winter be realistically expected. I would say that around three of the next nine months need a below average CET before anyone can start talking about a cold winter for 2007-08, or any future year.

2001 was a cool September followed by warm October surely?

Just checking a "warm September = mild winter" correlation; 1961-2 did not work too well with September 1961=15.2C (would not be beaten till 1999) , Dec 2.2C (well below average) Jan 4.3 and Feb 4.4 (both about average). Sep 1958 had a CET 15.1C, Jan 1959 was cold at 1.6C although Dec and Feb were near average.

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Summer of 95;

The point I am trying to make with the warm September = mild winter correlation is that it did not work absolutely every time in the past, but I am saying that the vast majority of winters that have followed a warm September have also turned out to be mild especially in the modern day. Re 2001 we actually found that year that the warm wet October does not work, and again in 2006. The theory is that cool wet Septembers / warm dry Octobers are the most favourable pattern to lead to a cold winter.

Saying all the above is true; actually 2005 did not fare too badly for the winter after a warm September / warm wet October; all months were at least reasonably average and the March was cold.

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September with a CET of 15 and >

2006 16.8 Winter CET: 6.0+

2005 15.2 Winter CET: 4.1

1999 15.6 Winter CET: 5.4

1961 15.2 Winter CET: 3.6

1958 15.1 Winter CET: 3.6

1949 16.3 Winter CET: 5.1

1929 15.3 Winter CET: 4.6

1898 15.2 Winter CET: 5.8

1865 16.3 Winter CET: 5.3

1825 15.1 Winter CET: 3.8

1795 16.0 Winter CET: 6.2

1780 15.6 Winter CET: 3.4

1779 15.2 Winter CET: 1.4

1760 15.7 Winter CET: 5.8

1750 15.2 Winter CET: 3.2

1731 15.3 Winter CET: 4.7

1730 15.3 Winter CET: 2.5

1729 16.6 Winter CET: 4.6

1708 15.0 Winter CET: 1.2

1678 15.0 Winter CET: 1.0

Winters with CET <2: 3

Winters with CET between 2 and 3: 1

Winters with CET between 3 and 4: 5

Winters with CET between 4 and 5: 4

Winters with CET between 5 and 6: 5

Winters with CET >6: 2

So there's 9 winters with a CET of less than 4C and 11 winters with a CET of greater than 4C

Does a mild, dry October increases the chances of the following winter being colder than average? I let you decide

1995 Oct 12.9 Rain 52.0mm --------> winter 1995-96 below average

1985 Oct 11.0 Rain 46.7mm --------> winter 1985-86 below average

1978 Oct 11.9 Rain 17.2mm --------> winter 1978-79 severe

1969 Oct 13.0 Rain 17.5mm --------> winter 1969-70 below average

1965 Oct 11.0 Rain 33.9mm --------> winter 1965-66 close to average notable cold spells

1908 Oct 11.8 Rain 56.2mm --------> winter 1908-09 slightly below average

1861 Oct 11.8 Rain 48.2mm --------> winter 1861-62 close to average

1809 Oct 10.2 Rain 10.9mm --------> winter 1809-10 slightly below average#

1806 Oct 10.6 Rain 41.9mm --------> winter 1806-07 slightly above average#

1793 Oct 11.3 Rain 52.9mm --------> winter 1793-94 fairly mild#

1790 Oct 10.3 Rain 56.9mm --------> winter 1790-91 fairly close to average#

1781 Oct 10.6 Rain 8.8mm ---------> winter 1781-82 fairly close to average#

1776 Oct 10.2 Rain 49.6mm --------> winter 1776-77 fairly cold#

1774 Oct 10.3 Rain 40.9mm --------> winter 1774-75 fairly mild#

# For that time period those Octobers could be considered mild.

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Summer of 95;

The point I am trying to make with the warm September = mild winter correlation is that it did not work absolutely every time in the past, but I am saying that the vast majority of winters that have followed a warm September have also turned out to be mild especially in the modern day. Re 2001 we actually found that year that the warm wet October does not work, and again in 2006. The theory is that cool wet Septembers / warm dry Octobers are the most favourable pattern to lead to a cold winter.

Saying all the above is true; actually 2005 did not fare too badly for the winter after a warm September / warm wet October; all months were at least reasonably average and the March was cold.

Yes, I thought of dropping in 2005-6 as another example; however decided not to because it the actual winter (not March) had no well below average months.

Looking at the figures just given by Mr Data, perhaps it's the DRYNESS of October we should be looking at not the temperature; a quick glance shows a fairly favourable correlation between dry Octobers and cold winters, albeit with the odd exception like 1972-3 which was mild. Certainly the recent tendency of Octobers to be very wet has coincided with a lack of cold winters.

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Thanks Kevin;

It appears that historically the vast majority of winters that have followed a warm dry October have turned out cold or at least reasonably average, and few have turned out mild. It does seem as though very warm Septembers (15*C+) do favour a mild winter except over two centuries ago.

Kevin, how about Septembers greater than 14.5*C and the winter that followed? Although the 1971-2000 September average is 13.7*C, the 20th Century (1901-2000) average for September is 13.5*C, so going by the 20th century standards a September with a CET of 14.5*C could be considered warm (1C above average). I would be grateful if you could produce a list of 14.5+ Septembers and the winter that followed? So it is clear that we have a clear guide as to what winter followed every warm September that was 1C or more above average.

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I think one of the signs we need is a return to a couple of more "traditional" weather types of years gone by. If you look at some books about holidays in scotland for example, the best time to visit Western Scotland was always May & september, This was due to regular blocking to the NE at those times of year & a frequent Easterly wind bringing dry, warm settled conditions to that area. (OK I know that Eastern Scotland & NE England wouldn't be very nice at the time!).

These regular patterns seem to have broken down, along with the Equinoctal storms & new year cold spell. The UK used to have some very predictable weather at certain times of the year, & whilst you could argue hat we have a new pattern i.e. 5 months of summer & 7 months of autumn, we need these more traditional patterns back.

Dave

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Hi Noggin, Tamara, Summer Blizzard (my cold weather friends) and all netweather guys including Mushy and even WIB,

What a great thread and one that I will be following for the remainder of the year.

You, like I and others, have been so sad with the mildness of this winter that it would be nice to look for the signals for what next winter might bring.

For me it would be the ultimate for those more expert than I to track what might be a memorable winter. It would also be good to see if the signals are not there so that we may not be too disappointed.

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I think one of the signs we need is a return to a couple of more "traditional" weather types of years gone by. If you look at some books about holidays in scotland for example, the best time to visit Western Scotland was always May & september, This was due to regular blocking to the NE at those times of year & a frequent Easterly wind bringing dry, warm settled conditions to that area. (OK I know that Eastern Scotland & NE England wouldn't be very nice at the time!).

These regular patterns seem to have broken down, along with the Equinoctal storms & new year cold spell. The UK used to have some very predictable weather at certain times of the year, & whilst you could argue hat we have a new pattern i.e. 5 months of summer & 7 months of autumn, we need these more traditional patterns back.

Dave

I've been wondering about this lately too. I remember reading Manley's book which stated that May and June were in most years fairly certain to be the driest, sunniest time of the year in west Scotland and he made a point about the Whitsun bank holiday being held in high regard there because of that. Certainly up until about 1997 what I call the "southeast versus the rest" summer setups (basically the summertime Bartlett High; southeast England is topping 25C in the sun while the northwest is catching lows skirting the high and raining; in between eg here it's usually cloudy and boring) seemed rare in these months whereas now they seem to occur in most years between May and August; quite often we seemed to get either a high stuck to the west which made west Scotland sunny and everywhere else cool and dull as in most of June 1995- (the weathertype I think Manley was on about), or warm sun everywhere as in most of May 1992, or cold washout weather in most parts as in June 1997 (although parts of west Scotland sometimes stay dry even in this).

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Hi fellow coldies Tamara, John and SB and thanks for the encouraging words! Thanks to everyone for their replies.

I have carefully read the replies and have jotted down a sort of summary (why not a winttary?) which I hope sums up what to look for. Some of it is a bit beyond my understanding at the moment but I shall use the Spring and Summer to become better acquainted with AO, QBO and La Nina/El Nino and their effects!

So we require (in no particular order!):

1) a miracle

2) a volcanic eruption in the NH (with no deaths)

3) lose the Indian Summers

4) cooler Septembers and drier Octobers

5) a generally cooler year with the resultant drop in SSTs

6) a blocked Autumn set-up with the subsequent cold pooling

7) no stratospheric cooling in Autumn

8 ) a generally more "traditional" type of weather pattern though the year and

9) 10) 11) the correct AO, QBO and La Nina/El Nino conditions which leave me a bit stumped at the moment!

The thought of learning these new things gives me hope for surviving the Summer. :)

It will be interesting to see how things unfold.

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Hi noggin,

Well summed up.

Now wouldent it be great for to get a scoring for each of these on a monthly basis from some of our experts and see if we can spot a trend that might deliver a very cold winter. This would be very simple and effective and not too scientific either.

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I just thought i would say that February recorded a neutral to negative PDO (Pacific Decadel Occilation which is one of the factors responsible for the negative AO recorded, this is significant in that this bucks the trend of recent years and signifies a downward trend, because of this, i would call for all three months to record a neutral to negative PDO however January to record the highest value and February to record the lowest value, possible -1>. The downside to this is that the PNA is also strongly linked to the PNA, thus a negative PNA will favour northerlies in combination with a negative AO rather than easterlies.

In regards to the MEI (El Nino/La Nina) February recorded a value of 0.5 which is a 0.5 drop since January, thus we could see weak La Nina values (-0.5) as early as May, though we are still looking at a declining La Nina through the winter with all three winter months seeing weak La Nina values.

The fall of the QBO halted in February, staying at a neutral to westerly value, when the QBO does turn easterly, this is a good thing as we will endure stronger easterly values next winter however some anologues did indicate a reasurgance of the westerly QBO, so this could be a worrying sign.

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http://jisao.washington.edu/pdo/PDO.latest

Sorry, i was wrong, February recorded a neutral to positive PDO, anologues for years in which both January and February recorded a neutral to positive PDO are:

2005

2004

2001

1997

1996

1993

1992

1982

1960

1958

Looking at that list, there are no ultra mild winters that followed, so that has to be a good sign.

http://www.cdc.noaa.gov/Correlation/mei.data

February recorded a weak El Nino figure of 0.5, the anologues for a moderate El Nino January followed by a weak El Nino February are:

2003

1995

1988

As you can see, it is a rare pattern and given that 1995 and 1988 were two of the mildest winters on record, you can see why we had such a warm winter, according to these anologues, we should see anything from a neutral ENSO to a moderate La Nina heading into next winter.

http://www.cdc.noaa.gov/Correlation/qbo.data

February recorded a neutral to weak westerly QBO, as did January, anologues for this are:

2000

1979

1962

1960

Looking at that list, we should expect a moderate to strong easterly QBO next winter.

http://www.cpc.noaa.gov/products/precip/CW...ent.ascii.table

No value has been given for Januarys AO value however it was deinitely positive to very positive, February recorded a negative AO value, the anologues for this pattern are:

1983

1957

From those anologues, we can expect next winter to feature a neutral to positive December and a February with a negative AO.

Taking the conditions in 1963 as those we need for a cold winter, we need all three months to record a neutral to negative PDO, all three months to feature a negative AO, all three months to feature strong easterly QBO values and all three months to feature weak La Nina conditions.

Given the anologues above, we have a high possibility of reaching the La Nina and QBO requirements and the AO requirement in February, however there are too many PDO anologues at the moment from which to draw any assumptions, therefore, i would say to expect a cold February.

1947 repeat???

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it just shows that care is the watchword.

this is what he/she posted

And so the outlook...

My initial indications are that the UK is more likely to experience average or colder-than-average conditions this winter. It is very likely to be much cooler than last winter, which saw the domination of mild, zonal conditions. The winter will likely be very similar to 2005/6, but with a lean towards La Niña, I expect a greater frequency of sleet and snow.

that was his/her forecast for 2006/07?

not very close in my view.

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