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The One True 2013-14 Winter Outlook Thread


jburns

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Putting the numerical description of El Nino and La Nina aside, the question is, how does the background state of the atmosphere behave? Is it currently behaving like a Nina or Nino? Or is it currently behaving like neither are in place (and neither are, going by the numerical values).

And how is the background state of the atmosphere expected to look if 3.4 continues to warm slightly? Will it act more Nino-ish? Or will any warming there be irrelevant until it hits a specific numerical value which would label it as an "official" El Nino?

I bring up those questions because year after year, there is always quibbling about numerical values of indexes and what they will mean to our weather. People love to point out how the NAO is about to go negative and get all excited. But if Canada is flooded with mild air or if the NAO sets up east-based, then the negative sign and the magnitude of it have little impact in bringing us cold an snow.

If I remember right (and someone correct me if I'm wrong here), last year, we had a neutral ENSO winter, but the atmosphere behaved Nina-ish, which I'm sure was attributable to both carry-over from the previous year's Nina and other factors acting on it (-PDO, +NAO, cold stratosphere, etc.).

So currently, is the background state of the atmosphere behaving in an El Nino, La Nina, or El Nada manner, and how is that likely to evolve throughout the winter, assuming slight warming of ENSO, which seems to be the most likely outcome at this time?

As I've pointed out many times, the point of meteorologists using a particular index for forecast guidance is that there are certain significant tendencies associated with each index rather than anything close to absolutes. So, their "official" values are well worth using for forecast purposes. If someone wanted the best shot at a solidly cold SE winter, a weak Nino (based on history) would give the best opportunity. Actually, the best combo is weak Nino/+PDO/-NAO/-AO though even that wouldn't guarantee it. Nothing guarantees it. A really good shot at a cold SE cold winter appears to come along with +PDO/-NAO/-AO without a weak Nino but that chance isn't as high vs. if there is a weak Nino along with +PDO/-NAO/-AO. Can there be a cold winter with neutral ENSO and some other combo of PDO/NAO/AO? Of course! But a weak Nino would still be strongly preferred based on history/analogs.

Another thing to keep in mind about ENSO and PDO is that they are SST based as opposed to the much more volatile atmospheric based NAO/AO. So, when trying to make very early winter forecasts, ENSO and PDO are quite useful in November since we have a pretty good idea of how they'll be in winter. Actually, that is much more the case for ENSO than PDO. Also, ENSO and PDO affect each other.

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As I've pointed out many times, the point of meteorologists using a particular index for forecast guidance is that there are certain significant tendencies associated with each index rather than anything close to absolutes. So, their "official" values are well worth using for forecast purposes. If someone wanted the best shot at a solidly cold SE winter, a weak Nino (based on history) would give the best opportunity. Actually, the best combo is weak Nino/+PDO/-NAO/-AO though even that wouldn't guarantee it. Nothing guarantees it. A really good shot at a cold SE cold winter appears to come along with +PDO/-NAO/-AO without a weak Nino but that chance isn't as high vs. if there is a weak Nino. Can there be a cold winter with neutral ENSO and some other combo of PDO/NAO/AO? Of course! But a weak Nino would still be strongly preferred based on history/analogs.

Thanks Larry. I get what you're saying about the preferred state (being and official weak El Nino) as well as the value of using a scale or numbers to define variables. What I'm asking/suggesting is that sometimes, can the atmosphere "act" Nino-ish or Nina-ish, even though the numerical value doesn't necessarily support designating it as such, and might this be one of those years?

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Thanks Larry. I get what you're saying about the preferred state (being and official weak El Nino) as well as the value of using a scale or numbers to define variables. What I'm asking/suggesting is that sometimes, can the atmosphere "act" Nino-ish or Nina-ish, even though the numerical value doesn't necessarily support designating it as such, and might this be one of those years?

Of course. Actually during just about any Nina, even the ones that do "act like" a Nina, there will be at least some periods that are Ninoish in the atmosphere. Likewise, during any Nino (even the ones that do "act like" a Nino, there will be at least some periods that are Ninaish in the atmosphere. Furthermore, in some cases, a Nino will actually act mainly like a Nina and vice versa. That's why there are strong tendencies rather than absolutes. So, any year, including winter 2013-14, might always be one of those years. The problem is in predicting that. That is more difficult to predict than going with the tendencies of an index.

In case you missed the edited part of my previous post, besides its strong tendencies, the value of ENSO over other indices in early November is that it is about the most stable and, therefore, predictable index months in advance. Neutral for this winter looks extremely likely. Winters associated with neutral in the SE US have been all over the place but have averaged fairly close to normal vs. the tendency toward mild for Nina and cool for Nino. So, based on ENSO, alone, the best guess would be to go with near normal. What will likely be the big determiners will be PDO/NAO/AO. Those are harder to predict, especially NAO and AO. Early indications for AO are for solid +AO per October Eurasian snowfall fwiw, which still isn't even close to a guarantee With the longterm -PDO, -PDO would have to be favored over +PDO right at this moment due to the absence of a Nino. However, that's far from a guarantee! Also, even if it ends up -PDO, will DJF average closer to -2, to -1.5, to -1, or to -0.5? That will obviously make a diff. Regarding NAO, the jury is still out. That may be the least predictable of these four indices. However, there is some tendency for the favoring of a DJF averaged +NAO when there is a DJF averaged +AO, which is currently favored if one believes in the October sub 60 N Eurasian advance index.

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Good stuff, Larry. Thanks for taking the time to articulate it. Still plenty of time to watch and see how things develop and how the baseline state of the atmosphere evolves as we head into late fall/early winter. This may be one of those years where it feels more like a Nino than a Nada, even though the numbers don't officially support it. That's my hope anyway, for the reasons you pointed out. We'll see. Thanks again.

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On the PDO, the newly released October value from NOAA came in at -1.51.  The progged Aleutian ridge / west coast trough would almost certainly deepen the negatives over the next few weeks.

 

That was expected as the classic -PDO N Pac anomalies briefly spiked before quickly dissipating as the +PNA came in.  The -PNA/-EPO may reverse this trend if it hold on too long. 

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5 SE Weather Forum Axioms

 

1. No matter what the weather is in November, SE forum members will find it has been followed by cold snowy winters in the past.

 

2. If it wasn't for the Hartsfield airport runway's heat sink effect, Atlanta would have the same winter temperature and snowfall average as Montreal. 

 

3. Wildlife(squirrels, worms, birds, moles) trump meteorologists in long range forecasting ability.

 

4. The warmer the winter, the earlier 1960 will be mentioned.

 

5. Cold winter, warm winter, wet winter, dry, living in Waycross will still make you cry.

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5 SE Weather Forum Axioms

 

1. No matter what the weather is in November, SE forum members will find it has been followed by cold snowy winters in the past.

 

2. If it wasn't for the Hartsfield airport runway's heat sink effect, Atlanta would have the same winter temperature and snowfall average as Montreal. 

 

3. Wildlife(squirrels, worms, birds, moles) trump meteorologists in long range forecasting ability.

 

4. The warmer the winter, the earlier 1960 will be mentioned.

 

5. Cold winter, warm winter, wet winter, dry, living in Waycross will still make you cry.

Hahahahahahah!!!!!! You NAILED it! :-)

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5 SE Weather Forum Axioms

1. No matter what the weather is in November, SE forum members will find it has been followed by cold snowy winters in the past.

2. If it wasn't for the Hartsfield airport runway's heat sink effect, Atlanta would have the same winter temperature and snowfall average as Montreal.

3. Wildlife(squirrels, worms, birds, moles) trump meteorologists in long range forecasting ability.

4. The warmer the winter, the earlier 1960 will be mentioned.

5. Cold winter, warm winter, wet winter, dry, living in Waycross will still make you cry.

:lmao: :lmao:
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5 SE Weather Forum Axioms

 

1. No matter what the weather is in November, SE forum members will find it has been followed by cold snowy winters in the past.

 

2. If it wasn't for the Hartsfield airport runway's heat sink effect, Atlanta would have the same winter temperature and snowfall average as Montreal. 

 

3. Wildlife(squirrels, worms, birds, moles) trump meteorologists in long range forecasting ability.

 

4. The warmer the winter, the earlier 1960 will be mentioned.

 

5. Cold winter, warm winter, wet winter, dry, living in Waycross will still make you cry.

 

Ha!

 

GVQfJGf.jpg

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5 SE Weather Forum Axioms

 

1. No matter what the weather is in November, SE forum members will find it has been followed by cold snowy winters in the past.

 

2. If it wasn't for the Hartsfield airport runway's heat sink effect, Atlanta would have the same winter temperature and snowfall average as Montreal. 

 

3. Wildlife(squirrels, worms, birds, moles) trump meteorologists in long range forecasting ability.

 

4. The warmer the winter, the earlier 1960 will be mentioned.

 

5. Cold winter, warm winter, wet winter, dry, living in Waycross will still make you cry.

That has a good chance of being this winter's sig file!

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FYI, FWIT from WSI for winter: "According to WSI Chief Meteorologist Dr. Todd Crawford: “The brutally cold early winter weather across the eastern US has been the result of a seemingly endless supply of Arctic air masses plowing southeastward across Canada. This pattern has been driven by strong and persistent atmospheric ridging across the North Pacific. As long as this ridging continues, the risk of widespread cold temperatures will continue. However, any weakening or displacement of this ridging will lead to significantly warmer risks across the US due to the expected strength of the polar vortex. There are several reasons why we expect a stronger-than-normal polar vortex this winter, including a weaker-than-normal Siberian high, a recent spike in solar activity, and the continuation of very strong westerly winds in the equatorial stratosphere. This strong polar vortex should generally confine the cold air to northern latitudes, and should allow much of the South to bask in a mild winter.”

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