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Gavin P

Nao Forecast For Winter 2012/2013

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Hey guys,

It's that time of year again when we can use May's Atlantic Sea Surface Temperature Anomalies to attempt to come up with a possible NAO forecast for the subsequent winter.

This years Atlantic temperature anomaly points towards a Positive NAO for winter 2012/2013!

Find out why and how in my video presentation, which you can see here:

http://gavsweathervids.com (just for today)

And here: http://gavsweathervi...m/seasonal.html

The closest match I could find to May 2012's Atlantic SST anomalies was May 2000, which is interesting because the Met Office forecast a strongly positive NAO for winter 2000/2001, but we actually ended up with a slightly negative NAO in the end (probably because of the unusual autumn weather pattern we had in 2000)

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Thanks for posting that video,very interesting.

Winter 2000/2001 certainly more in the -NAO category.

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Great forecast! All to play for!

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Thanks guys. smile.png

As I say at the end of the video, there are a LOT of differant things you can look at in terms of trying to get a winter forecast together (Siberian snow cover, solar, ENSO, etc..) and most of them don't even begin to to come on to the radar until September at the earliest.

The NAO forecast from May's Atlantic SST anomalies is just one part of the puzzle (though the Met Office clearly believed/believe that its quite an important part as aside from their dynamic model this seemed to be their main methodolgy in terms of making winter forecast predictions)

So yes, all to play for is a fair description.

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A lot of work in those videos Gavin so thanks for that and in the main quite well put over.

One point, in the summer one-simply because CFS does not show any marked +ve or -ve signals does not mean, as you put it, 'it has not got a clue'. The model is showing there are no substantial anomalies so temperature and precipitation levels are being forecast to be near the normal?

As you obviously enjoy doing the videos, how about, re winter predictors of the NAO, a look at those May predictors, as many as you can find, predicting +ve or -ve NAO and what the actual winter months turned out to be. That way we then get some kind of statistical view of how successful these May predictors using SST's really are?

just a thought but I can imagine another load of work for you.

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Thanks John. smile.png

Well, on the CFS point, I was really talking about the entire Northern Hemisphere apparently not having a positive or negative height anomaly anywhere. Of course its possibe that the CFS thought the whole northern hemipshere would be "average" but I do remain quite suspicious of the CFS model. I just don't find it that stable if you know what I mean. doh.gif

On past - and + NAO forecasts and how they verified, the Met Office had/has a fantastic graph going back some 20 years or more with their NAO predictions and verification included. I really, really wanted to include it in the video as I felt it would be really useful, but when I contacted the Office to try and get the link to the page they told me I'd have to pay £75+VAT for the information. ohmy.png

Anyway, I'd love to do more on the NAO and May SST connection (I couldn't do anymore in this video as my voice was about to give out at any moment, lol) so watch this space.

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Interesting....think we could have another 'conflicting signals' winter on our hands. Last winter has proven that the state of the strat plays a major role in determining the weather patterns that we experience....something I believe the MetOffice has just recently invested more time in studying? For me, the sea surface temps of the north Atlantic provide nothing but a vague indicator of the tendency for pressure distribution and the link IMO is tentative at best regards the May-proceeding winter hypothesis.

I'm not in anyway slating this method but from memory it has been very hit and miss in the past which leads me to believe it's a signal that can easily be overridden.

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There is certainly merit to the NAO theory however i focus on more important teleconnections and do not see any conflicting signals.

From my prospective we have a likely weak El Nino, weakening (neutral AO/NAO signal), near neutral QBO conditions (neutral signal again) but importantly a negative PDO which is correlated with -AO/NAO conditions. In addition to this we see an active MJO this summer and an active hurricane season due to the -QBO which is likely to add ozone to the atmosphere.

I don't think next winter will be as good as 2010 but i am bullish enough to state that we will get the second coldest winter this century.

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Thanks for the interesting and informative video. Didn't the Atlantic SST's in May 2009 also point towards a postive NAO for the following Winter? I seem to remember the Met Office going for a strongly positive NAO for Winter 2009/10. If I'm correct then along with May 2000 that gives some comfort for the cold weather fans. However, on the other hand Winter 2012 could indeed have a strongly positve NAO and be similar to those of 1988/89 or 2006/07 depending on other factors. As usual, come Autumn, it will be interesting to see how these all start to come together. All along way off yet anyway.

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Hi Gavin,

Without calling your methods into question, I found the opposite to be the case for May this year. I had a look at the stats for my local weather station (Royston,Herts) and I noticed that the winds were very much coming from a northerly or easterly quarter for most of the month so I checked out the synoptics for May and saw for around 2/3rds of the month, there was high pressure over greenland or the mid atlantic causing the jet-stream to head further south forcing the storm track over the channel, thus giving us the appauling month we had. Wouldn't that suggest we had a neutral or negative phase of the NAO for the month? I could be reading this completely wrong so bear with me smile.png

Alex

P.S May 2012 looked incredibly similiar to 2008,9 and 10

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Good work gavin. How ever going by last winter i think the stratosphere has a big part to play. I will keep a close eye on the strat when chio opens the new thread for 2012 2013.

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I personally feel that there is little merrit in this and its basically a no-brainer to call +NAO from this far out. At very worst its no better than flipping a coin.

Heads positive NAO and tails negative NAO. Who goes first ?

Lets not forget that the default lends itself to a positive NAO, particularly when its been so long since the last that on a balance of probabilities a +NAO is long overdue.

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Hi Gavin,

Without calling your methods into question, I found the opposite to be the case for May this year. I had a look at the stats for my local weather station (Royston,Herts) and I noticed that the winds were very much coming from a northerly or easterly quarter for most of the month so I checked out the synoptics for May and saw for around 2/3rds of the month, there was high pressure over greenland or the mid atlantic causing the jet-stream to head further south forcing the storm track over the channel, thus giving us the appauling month we had. Wouldn't that suggest we had a neutral or negative phase of the NAO for the month? I could be reading this completely wrong so bear with me smile.png

Alex

P.S May 2012 looked incredibly similiar to 2008,9 and 10

We look at the SST's in May with a view to how the Atlantic *MAY* force the atmosphere in winter. The things that dictate the NAO in winter are not the same as the things that dictate the NAO in May - Remember April and May will usually have more northerly and easterly winds than any other time of year due to the decline of the westerlies which is a common occurance in spring, primarily because the arctic is warming and the PV is breaking down.

Good work gavin. How ever going by last winter i think the stratosphere has a big part to play.

Indeed. Its just one part (small, big?) of the puzzle. No more, no less.

I personally feel that there is little merrit in this and its basically a no-brainer to call +NAO from this far out. At very worst its no better than flipping a coin.

Heads positive NAO and tails negative NAO. Who goes first ?

Lets not forget that the default lends itself to a positive NAO, particularly when its been so long since the last that on a balance of probabilities a +NAO is long overdue.

Thanks.

Just one point I'd like to make.

If the sea surface temperature anomaly had indicated a negative NAO for the subsequent winter (in other words if there had been the warm, cold, warm tripole) I'd have called it that way. So this isn't a "balance of probability" or "no brainer" call but a genuine attempt to use May's SST's anomalies to predict the NAO next winter.

Whether you think theres any merrit in this particular methodology or not is of course up to you. smile.png

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I suspect that if using the SST idea gave a better than 50/50 probability using past winters as an example then it would have been used by professional sites.

There is NO simple way of predicting weather even 1 day in advance let alone 2 seasons away. We do appear to be making some progress towards a better than even probability but are still a long way from being accurate enough often enough for me to feel anyone, professional or amateur has a real handle on things.

Please don't think I am knocking anyone and their ideas I am not. Only by trying time and time again with different ideas and perspectives does science, including meteorology or climatology, move forward.

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I suspect that if using the SST idea gave a better than 50/50 probability using past winters as an example then it would have been used by professional sites.

Well it was used by the UK Met Office for years (still is as far as I know, just they don't make their findings public anymore after the media bullied them into silence sad.png ) in conjunction with the long range dynamic model.

I agree though, I certainly don't see NAO forecast as the be all and end all. I definately wouldn't want to resolve an entire winter forecast around this one prediction.

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It's that time of year again when we can use May's Atlantic Sea Surface Temperature Anomalies to attempt to come up with a possible NAO forecast for the subsequent winter.

The question I ask is why May? What is so special about May? Why not November? I don't see how a month that is 6 months away can be used.

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The question I ask is why May? What is so special about May? Why not November? I don't see how a month that is 6 months away can be used.

I believe the sea surface temperature anomalies that occur in May have a tendency to re-occur in the subsequent winter.

How that happens and what the mechanism is that cause's it, I don't know I'm afraid. :)

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Just analysed the QBO data breaking it down into neutral, positive and negative and we see that with the QBO looking neutral or positive this winter, it does not bode well.

Will do the same for the PDO and MEI when i get a chance.

Version:1.0 StartHTML:0000000168 EndHTML:0000007836 StartFragment:0000000468 EndFragment:0000007819

QBO

positive


  • December

1982 - B

1985 - A

1987 - A

1990 - B

1992 - B

1994 - A

1997 - A

1999 - A

2006 - A

2008 - B

2010 – B

45% BELOW AVERAGE

55% ABOVE AVERAGE


  • January

1981 - A

1983 - A

1986 - B

1988 - A

1991 - B

1993 - A

1995 - A

2000 - A

2002 - A

2009 - B

2011 – B

37% BELOW AVERAGE

63% ABOVE AVERAGE


  • February

1981 - B

1983 - B

1986 - B

1988 - A

1991 - B

1993 - A

1995 - A

2002 - A

2009 - B

2011 - A

50% BELOW AVERAGE

50% ABOVE AVERAGE

negative


  • December

1979 - A

1981 - B

1983 - A

1986 - A

1989 - A

1991 - A

1996 - B

2000 - A

2003 - A

2007 - A

2009 - B

2011 - A

25% BELOW AVERAGE

75% ABOVE AVERAGE


  • January

1982 - B

1984 - B

1987 - B

1990 - A

1992 - B

2001 - B

2006 - B

2008 - A

2010 - B

2012 - A

70% BELOW AVERAGE

30% ABOVE AVERAGE


  • February

1982 - A

1984 - B

1987 - B

1992 - A

1994 - B

2001 - /

2006 - B

2010 - B

2012 - B

67% BELOW AVERAGE

22% ABOVE AVERAGE

neutral


  • December

1984 - A

1988 - A

1993 - A

1995 - B

1998 - A

2001 - B

2002 - A

2004 - A

25% BELOW AVERAGE

75% ABOVE AVERAGE


  • January

1979 - B

1985 - B

1989 - A

1994 - A

1996 - B

1997 - B

1998 - A

1999 - A

2003 - A

2004 - A

2005 - A

2007 - A

33% BELOW AVERAGE

67% ABOVE AVERAGE


  • February

1979 - B

1980 - A

1985 - B

1989 - A

1990 - A

1996 - B

1997 - A

1998 - A

1999 - A

2000 - A

2003 - B

2004 - A

2005 - B

2007 - A

2008 – A

33% BELOW AVERAGE

67% ABOVE AVERAGE

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Might not bode well for cold lovers, but bodes well for my NAO forecast, SB.drinks.gif

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Hmm I think it's about time I took a Winter holiday to Canada!

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So now that we are in July, we are approaching the time of year when the first signs of the northern winter arrive, namely in this post the -10C isotherm which was present by the 1st August in 2000, 2002, 2003, 2010 and 2011.

Personally i am a great believer that the earlier the cold, the earlier the snow and the greater the feedback later in winter on a hemispheric scale.

Only a month or so before winter arrives in Siberia again!

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So now that we are in July, we are approaching the time of year when the first signs of the northern winter arrive, namely in this post the -10C isotherm which was present by the 1st August in 2000, 2002, 2003, 2010 and 2011.

Personally i am a great believer that the earlier the cold, the earlier the snow and the greater the feedback later in winter on a hemispheric scale.

Only a month or so before winter arrives in Siberia again!

Yes will be interesting to see how quickly the -10 isotherm appears. Those years you mention brought a mixed variety of winters, only 2010 delivering a notably severe cold spell in the preceeding winter at least in our neck of the woods, for europe I think there was quite alot cold in winter 00/01, 02/03 and winter 10/11 hung on longer in europe and of course we have last feb in 2012.

Isn't a warmer northern hemisphere in the autumn better though for promoting high pressure and less cyclogensis to our north, but yes perhaps what occurs in siberia has a much greater influence overall on the wider picture - I remember the build of strong heights during late october in 1995 which brought a early cold spell in NW Russia - a sign of things to come.

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Yes will be interesting to see how quickly the -10 isotherm appears. Those years you mention brought a mixed variety of winters, only 2010 delivering a notably severe cold spell in the preceeding winter at least in our neck of the woods, for europe I think there was quite alot cold in winter 00/01, 02/03 and winter 10/11 hung on longer in europe and of course we have last feb in 2012.

Isn't a warmer northern hemisphere in the autumn better though for promoting high pressure and less cyclogensis to our north, but yes perhaps what occurs in siberia has a much greater influence overall on the wider picture - I remember the build of strong heights during late october in 1995 which brought a early cold spell in NW Russia - a sign of things to come.

Indeed, some summers even lose the -5C isotherm although we managed to have kept it so far.

Yes, while they are variable for the UK being a small island i believe that there is a decent correlation between Europe and the eastern USA as 03 and 10 were both notable for being cold (pretty sure that 01 was as well). Hopefully we should keep a -PDO to enhance any effect.

There is a strong correlation between above average October snowfall (on a hemispheric scale) and a -AO (also a correlation between the -PDO and -AO), this is likely a result of outgoing radiation and its stratospheric feedback as snow cools the area around it and below -15C you typically see a surface high.

If there is one thing we have learnt in recent winters, it is that the stratosphere will override most other signals.

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hey guys i would like to heare what u guys think of this winter 2012-2013 winter forecast.

This is the update to the 2012-2013 Preliminary Winter Forecast. We will start off with an ENSO update and go from there.

enso_update/sstanim

In the last month or so, we have seen warm sea surface temperatures making a rebound to areas just north of the ENSO monitoring area, with a little cooling

actually occurring in Nino areas 1+2. Warming has actually receded north as a whole, slightly cooling down the western portions of the ENSO monitoring

area. However, an indication of what's to come is underwater.

anim/wkxzteq_anm

(Refresh page if it stops looping)

As seen in this animation, warm water has recently been welling up from a depth of about 100-200 meters in the Nino 3.4 and 4 regions. This warm water has

been steadily progressing upwards towards the surface, but also shifting east as it does so, indicating that warm water in the east is being supplied by

the west, which only means that this warm water in the western ENSO region will have to come up sooner or later. As the seasons progress into July and

August, we should start to see enhancement of these warm areas and an eventual upwelling of the warm water in the western ENSO regions.

An El Nino Watch was issued just over a week ago by the Climate Prediction Center, as seen in

this post.

An El Nino Watch is issued when conditions are at least 50% favorable for an El Nino to form in the 2nd half of 2012. As a recap, an El Nino is warming

of ocean waters in the Pacific Equatorial region.

The next thing we can see indicating an El nino is something called Outgoing Longwave Radiation, or OLR. Basically, a negative OLR value means more thunderstorms,

which signifies an El Nino, whereas a positive OLR index tells of less convection than normal, AKA a La Nina. Let's take a look at the last 5 months of

OLR observation.

s400/Screen+Shot+2012-06-08+at+2.27.47+PM

The OLR has been strongly positive in January and February, where we did have a solid La Nina. However, it is evident that this La Nina did weaken in March

and April, and last month in May, we did have a very slight negative value on the OLR, which tells me that the La Nina is officially over, and we are beginning

to wane into a potential El Nino situation for the 2nd half of the year and into 2013.

s400/01mb9065

Something else we watch for is the stratosphere. Here, we see that temperatures at the 1mb level are right up against the 1979-2008 minimum levels, which

does indicate that warmer weather should prevail for a little while. If the stratosphere drops below average levels going into the winter months and stays

like that, we could very well have a repeat of last winter, where the stratosphere couldn't either warm or stay warm long enough to provoke typical winter

weather. This abnormal cooling is also occurring at the 70mb level, which is where warming in the stratosphere becomes significant enough to provoke winter

weather into action around the winter months.

s400/ssn_predict_l

The sun will be a player in this winter, and this sunspot cycle will be abnormally low. The maximum number of sunspots will occur next year, and it will

be just around 60- much lower than the 110-something sunspots in 2000. This will be a more interesting around 2020, when the number of sunspots stands

at around 0. However, there will likely be some small effect on temperatures, and it should be a little lower than what it would be at normal sunspot level.

Let's look at this new solar cycle 24 in comparison to previous cycles.

s400/cyclcomp1

The graphic above shows the current solar cycle in violet compared to the previous few cycles. Cycles 21 and 22 were fairly normal and very similar, but

Cycle 23, in red, came out weaker than the previous two cycles. And now, since 2008, Cycle 24 has been the weakest of all, exhibiting a trend that the

sun is indeed cooling down. I expect that this lower than normal cycle will probably not affect our upcoming winter that much, but in the next several

years, a cooler than normal trend should be observed.

Something I really want to share with you is the relation of the Pacific Decadal Oscillation to this winter.

s400/ENSOandPDO

In the image above, you can see the PDO and ENSO effects on the Pacific ocean. A Positive PDO induces cooler than normal waters across the area to the southwest

of Alaska, with warm waters in the Gulf of Alaska and in the ENSO area, suggesting that a +PDO and El Nino may have a slight correlation. The same potential

correlation happens with a La Nina and -PDO, with warm waters in the areas southwest of Alaska and somewhat cooler waters in the ENSO areas. That said,

let's look at the PDO forecast I posted a little while back from the ESRL's LIM PDO model forecast, which I am unable to like to due to technical difficulties

at the ESRL.

s400/pdoplum

The PDO is forecasted by the ESRL to stay strongly negative going into the next year. This does appear to be likely, as we are currently in a negative phase

at the time of writing (

source).

Considering that we are in and will be staying in a negative PDO, it can be expected that a generally warmer body of water than usual will be sitting in

the areas off the Asian coast.

I decided to put in another set of analogues, but this time trying to pinpoint the scenarios that may happen for us. I used years with El Ninos and Negative

PDO values (

source 1)

(

source 2).

s400/cd64.53.178.223.164.18.34.10.prcp

Temperature Anomalies in El Nino and Negative PDO Years

s400/cd64.53.178.223.164.18.38.19.prcp

Precipitation Anomalies in El Nino and Negative PDO Years

Temperatures in these years were pretty warm in the western half of the US, including the Rocky Mountains. Near-average temperatures were observed in the

eastern US, with cooler than normal temperatures in the Northern Plains. As for precipitation, values were pretty much average across the nation, with

above average precipitation in the Northwest. By the way, I did compare observed drought values for these years (

source)

compared to May 2012 (

source),

and they correlated very nicely, indicating that these years do indeed have a correlation with this situation. Again, this is just an observation into

what could happen with an El Nino and negative PDO.

Now we get into the analogues that I am using to make a much better determination of this winter's potential.

Now, let's check out years that followed two La Ninas in a row. The years I used were:

•1963

•1972

•1976

•1986

•1997

•2009

It should be noted that while some of these years could be called neutral, I was looking to see if they were still in negative territory and it seemed

that the two years in question remained connected by the same La Nina event, by one way or another.

s400/cd64.53.178.223.165.14.40.13.prcp

Temperature Anomalies in December - February for the years mentioned above

s400/cd64.53.178.223.165.14.40.28.prcp

Precipitation Anomalies in December - February for the years mentioned above

What we see as the result are basically El Nino conditions, which is a given, considering an El Nino is expected this winter. It should be noted that the

strength of the El Nino was not taken into effect this time around for these years. Looking at temperature anomalies, we see warmer than normal conditions

in the northern US, with cooler than normal temperatures and wetter conditions along the Southern US. Dry conditions prevailed in the Ohio Valley.

Now, let's take the same years listed above and pick the ones with weak to moderate El Ninos (classified as +0.5 to +0.9 for a weak Nino, and +1.0 to

+1.4 for a moderate El Nino).

As a result, we have:

•1963 (Moderate El Nino)

•1976 (Weak El Nino)

•1986 (Iffy Moderate El Nino)

•2009 (Can Pass for a Moderate El Nino)

1972 was thrown out as it was a very strong El Nino, as was 1997. I did include 1986, which was classified as a strong El Nino. I included 1986 because

it was a moderate El Nino in December -February. 2009 was a tough choice. i did decide to include it, despite the fact it was a strong El Nino, because

it was borderline strong, and it is one of the analogues that is being buzzed around the weather world recently.

Putting the 4 years listed above, we have these results:

s400/cd64.53.178.223.165.14.49.36.prcp

Temperature Anomalies in weak or moderate El Nino's following a double dip La Nina

s400/cd64.53.178.223.165.14.49.50.prcp

Precipitation Anomalies in weak or moderate El Nino's following a double dip La Nina

This result turned out substantially different than the previous images. We now have a cool eastern half of the US, with only a bit cooler temperatures

in the Northern Plains than the previous 2 images. Precipitation remains roughly the same, with a wet Southeast and dry Ohio Valley and Northwest regions.

Let's discuss analogues in specific. 1976 is a good one, in my eyes, because I compared charts for Chicago, Illinois, from this year and 1976, and found

both years to have well above average late winters and springs. Towards fall and winter of 1976-77, the temperature sharply dropped and averaged below

normal for those seasons.

1986 was a little less on the ball. 1986 involved temperature swings that seemed to equal themselves out, with no defined above average phase or below

average phase. However, there are some sharp spikes in Chicago temperatures from 1986 in the first half of the year, and that could correlate with the

upcoming winter.

2009 was a curveball. There were small phases of above normal temperatures, and small phases of below normal temperatures throughout the year in Chicago.

The first half of the year involved a mainly below normal temperature phase, but the first few months eventually brought a nice, warm temperature swing.

This analogue could be a fair one.

1963 had a fairly similar situation as 1976, but 1963 began cool and stayed warm throughout the year before completely tanking in the last month or so

of the year. They both follow a cool-down in the last part of the year, but 1963 began a little too cool for my complete satisfaction.

It should be noted that the 1950-1980 timeframe involved a negative PDO, whereas the 1980s were in a warm PDO. That said, I think I will discount it. 2009

was a pretty neutral PDO, on its way to a negative phase, where we are now, so I want to keep it in the game.

As if this wasn't long enough, let's make up one final analogue set using 1976-77, 2009-10, and 1963-64.

s400/cd64.53.178.223.165.15.5.37.prcp

Temperature Anomalies for Weak/Moderate El Nino years following a double dip La Nina in a -PDO

s400/cd64.53.178.223.165.15.6.5.prcp

Precipitation Anomalies for Weak/Moderate El Nino years following a double dip La Nina in a -PDO

Temperature anomalies changed dramatically with this, and it shows that the eastern half of the US, as well as the Northern Plains, are now on the cooler

side of things. Precipitation didn't change too much, so temperature is the real big thing now.

Something else I am watching is an index called the Quasi Biennial Oscillation, or QBO. It involves wind patterns in the stratosphere. When the QBO is

negative, winds are going in a westward direction. A positive QBO leads to winds going in an eastward direction. Now, last winter there was a lot of hype

over sudden stratospheric warmings, or SSW's. An SSW has enhanced potential when the QBO quickly changes from positive to negative, leading to intense

and sudden warming in the stratosphere.

Now, I decided to look around and see if I could find a relationship between the QBO and equatorial convection. I did find an interesting article, and

I was able to determine from the information provided that tropical convection is deeper, or stronger, in the Negative QBO than in the Positive QBO. That

said, it would be logical to find a negative QBO in an El Nino situation, due to the fact that El Ninos are characterized by abnormally high levels of

convection. This is also logical, as a negative QBO contributes to a Negative NAO, which in turn combines with the El Nino to produce intense Northeast

snowstorms.

I also found a correlation between Outgoing Longwave Radiation (OLR) and the Quasi-Biennial Oscillation (QBO). When there is enhanced convection in the

equatorial region, the OLR becomes negative. That said, a negative OLR is more tilted to be indicative of an El Nino. Deep convection is characterized

by a low OLR, as stated earlier. If the Negative QBO supports deeper convection, then it would only make sense that both the QBO and OLR have a relationship

with each other and the ENSO pattern. However, not all of these will definitely happen, but they do have an increased likelihood of happening in correlation

with each other.

Right now, we are in a neutral ENSO situation that appears to be heading towards an El Nino, and this has been reflected by a very weak negative OLR anomaly.

However, the QBO has recently been tanking to very low levels in recent months. I find that this is not a surprise, as I showed above the upwelling of

warmer waters in the ENSO region. Since the QBO is negative, I would expect at least one ENSO region to be in an El Nino state of warmer than normal waters.

To be quite honest, I have a feeling that the eastern ENSO areas could pass off having an El Nino right now. If the QBO is negative, I would expect the

OLR to become negative soon, as warmer waters at the surface increase convection, keeping the QBO and OLR in negative territory.

Keep in mind that just because the QBO and/or OLR are negative, an El Nino is not guaranteed to form. It is just in the favor that these align with an

El Nino.

All of that said, here is my forecast for winter 2012-2013.

-Weak to Moderate El Nino will be here for winter.

-Cool temperatures have the potential to take the eastern US by storm this winter.

-Precipitation could be on the below normal side in the Ohio Valley, but that is not for sure just yet. A weak El Nino can bring above average precipitation

to the eastern US, while a stronger Nino does not.

-Considering we may be heading into an El Nino, I am liking the idea that the South US and East Coast will get above normal precipitation. Yes, that means

more snow for the East Coast.

-Cold shots ought to reach across much of the Eastern US, so some crops in the Southeast may be at risk.

Thank you so much for reading.

Andrew.

http://theweathercentre.blogspot.com

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A according to Matt Hugo, the EC seasonal forecast update signals a -ve pressure anomaly to the NW of the UK, meaning a +NAO, ultimately meaning wet, windy & mild.

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