Winter 2017-18 Disco

[CAPE]

18 minutes ago, showmethesnow said:

 

 

Thought I would run some analogs on this list. Haven't done this in so long I hope I did it correctly.

Have a limit to how many years you can throw in so I dropped 74, 89, 00 because of their high Nina values which i don't think we will achieve (Famous last words).

DJF 

 

November

December

January

February

March

Much better look then I was expecting. Good blocking shows up in the second half of winter through March which suggests a back loaded winter. 

Man that Feb composite has a a Cold and dry look.

[Bob Chill]

@showmethesnow

Use the northern hemisphere view in the drop down. It's easier to visualize for our purposes. Maybe open up the climo window too instead of 1981-2010. Climo heights are higher in that period and your using a number of pre 81 analogs. Helps smooth things out and really pinpoint the anomaly locations. I'm interested in what stands out. Nice work. 

[WxUSAF]

Good discussion folks.  

[showmethesnow]

32 minutes ago, Bob Chill said:

@showmethesnow

Use the northern hemisphere view in the drop down. It's easier to visualize for our purposes. Maybe open up the climo window too instead of 1981-2010. Climo heights are higher in that period and your using a number of pre 81 analogs. Helps smooth things out and really pinpoint the anomaly locations. I'm interested in what stands out. Nice work. 

Thanks. Maybe try to do that tomorrow in the morning if no one else gets to it first.

[BristowWx]

Farmers Almanac already off to a rough start calling for a weak El Niño and basing their forecast on that.  Mild and wet for us.  Poppycock.  

[showmethesnow]

Have a correction to the post above. I pulled the wrong years (used the year that began winter instead of the year that ended winter) for DEC-FEB so the correct one is below. 

 

 

@Bob Chill 

Had no luck with finding pre 81 climo. Reading a bit on the site and it may longer be an option.

[showmethesnow]

Here is the N Hemisphere view from the post above.

Dec-Feb

November

December

January

February

March

 

 

 

[Jebman]

On 9/19/2017 at 10:45 AM, BristowWx said:

And its that ridging that I remember as part of the ugly factor last winter.  In fact, I was looking through posts from last winter and it was just painful to read again as if it was just happening....the panic room was hopping like a Vegas casino where everyone was drunk and losing their money.... especially painful reading around the holidays where we THOUGHT the pattern would turn in Jan.   

Except for me. My persistent optimism in the 2016-17 Winter was utterly off the charts.  I was never ever going to get buried from panicking. I never panic. I KNOW it will snow in Dale City, because I live in a Snow Town.

Besides, I don't get drunk at casinos like MGM. I track cycles, time the slots, then I hit. I live only 24 - 35 minutes away from MGM Nat'l Harbor depending on traffic conditions. I am getting those slots DOWN. My win/loss ratio is generally about 55/45.

If you think you are lucky, THEN YOU ARE LUCKY!

 

[psuhoffman]

5 hours ago, showmethesnow said:

Here is the N Hemisphere view from the post above.

It's my fault, I should have simply included the full year like 1949-50 instead of just 1950.  I was being lazy.  But I used the January of the winter to identify year.  So some of those years are still wrong.  For the winter of 1950 for example, it would be December 1949.  Also, even with the right years I am not sure a mean plot will tell us much because there were such drastically different winters within the analogs.  There are some common threads.  No big HECS storms.  No historically great winters.  But within those goalposts, there was a range from a few total dud non winters to some pretty cold/snowy ones.  The string of years in the 1960s for instance would skew things towards a -NAO since some of those had an off the charts NAO.  That would not mean we are likely to see a -NAO for instance just because the -NAO years were so extreme that it biased the mean in that direction.  I think the data does indicate the NAO is the key here.  If we get NAO help this winter is "likely" to be ok.  If its another positive NAO year were in big trouble.  Once we figure out which way that is likely to go, then we can weed out the positive NAO years and those mean plots would become more useful.  Right now they are getting to a mean by averaging wildly different years together. 

[Bob Chill]

6 minutes ago, psuhoffman said:

It's my fault, I should have simply included the full year like 1949-50 instead of just 1950.  I was being lazy.  But I used the January of the winter to identify year.  So some of those years are still wrong.  For the winter of 1950 for example, it would be December 1949.  Also, even with the right years I am not sure a mean plot will tell us much because there were such drastically different winters within the analogs.  There are some common threads.  No big HECS storms.  No historically great winters.  But within those goalposts, there was a range from a few total dud non winters to some pretty cold/snowy ones.  The string of years in the 1960s for instance would skew things towards a -NAO since some of those had an off the charts NAO.  That would not mean we are likely to see a -NAO for instance just because the -NAO years were so extreme that it biased the mean in that direction.  I think the data does indicate the NAO is the key here.  If we get NAO help this winter is "likely" to be ok.  If its another positive NAO year were in big trouble.  Once we figure out which way that is likely to go, then we can weed out the positive NAO years and those mean plots would become more useful.  Right now they are getting to a mean by averaging wildly different years together. 

Yea, no surprise the big -nao years paint the picture of at least "cold enough to snow". We don't need a big giant block parked for months on end either. Tendencies and storm track play a big role. The current seasonals show high heights in the 50/50 region. We know exactly how that plays out. Predominant NW storm track with cold shots coming on the heels of rain storms. The EPO can buck that trend with cold air moving through in a progressive pattern (ala 13-14/14-15). On the other hand, we can get a good -AO/NAO has have it get totally fooked by the pac (ala 12-13). 

Mixed signals this season are to our advantage. There won't be much hype one way or the other leading in. Just pointing out possibilities and seeing how it breaks over time. It's crazy how fast time is moving. We're less than 2 months away from early Dec showing on the ensembles. Please let there be a big red ball over the pole....lol

[psuhoffman]

19 hours ago, Bob Chill said:

We all root for different things based on latitude. Just like you said (and the reason I changed the thread title) is it really does come down to blocking or bust. The further north you go the less you want a big block. Once you get far enough north, a big block means dry and cold. And not all blocks are created equal. A general -AO state favors decent snow up and down the east coast. Many times the NAO decides winners and losers. Many of our big hits don't include the NE. It's an intricate dance that lies in the hands of the NAO. 

 

For now I'll hug the WDI. That's tilted far in favor of a -NAO this year. And if not this year then next year. Otherwise it will be a record. It's been 6 consecutive +NAO winters. That's the upper limit in recent history. 

The NYC thing seems silly to me.  There are so many misconceptions regarding their climo compared to DC.  One thing I bet would shock most is since 1950, NYC and Washington DC have both had exactly 24 years with above average snowfall.  They are no more or less likely to have a good winter then we are.  The problem is they can have a "bad" winter and some down here still look on it with envy because its more then us.  But their climo is more then us.  If we get a total crap winter and only eek out a few 1-3" storms to end with 8" while we watch them cash in on a couple 4-8" storms and finish with 17" if feels like they did way better then us.  But with regard to climate they had the same crappy winter we did.  That's just their climo vs ours.   There is also the recency bias.  Since 2000 NYC has had 12 above average snow years while DC has only had 5.  But from 1970 to 1990 DC had 9 above average years and NYC only 3.  It seems to be cyclical.  I am not sure what the trigger is, but the AMO might have something to do with it.  It seems when the AMO is negative DC is more likely to have above avg snow then NYC.  When the AMO is positive NYC has the advantage.  That just sticks out looking at the numbers.  It could be a coincidence.  Finally, there are some patterns that are different in DC then NYC.  But the data for -PDO, -QBO, cold enso is pretty similar.  This is one pattern where they are in the same boat as us actually. 

[snowman19]

20 hours ago, psuhoffman said:

The NAO plays a HUGE part.  I broke down each year in the entire list by month and found there were 25 months with above average snowfall.  I then looked at each of those.  Only one pulled it off with a positive NAO and it wasn't even that positive, it was like +.7  That kind of a number could easily be hiding a 10 day period with a decent negative NAO.  That was January 1957 btw.  All the other 24 months with above normal snowfall had either a negative NAO or a neutral one, and looking at the neutral years I can say they probably had periods of -NAO hidden within the neutral monthly numbers.  In other words...if we don't get a -NAO kiss our snow chances goodbye.  Its almost unheard of to luck our way into snow in a positive NAO in this type of pattern.  That is the one obvious thing that pops out in the data.  So we need a -nao to have a chance.  So the years in the analogs that were wall to wall +NAO sucked.  What separates the other years seems to be simply getting lucky with well timed blocking and storm track.  But when the NAO goes positive...it will get ugly for snow chances in a -PDO cold enso pattern.    

There are a lot of assumptions being thrown around that I am not sure will hold up this year.  One is that there will be a ton of miller b, and another is that NYC is in a much better spot then us.  Looking at all 14 years with a -PDO, cold enso, -QBO, NYC only had one winter with above average snowfall.  NYC averaged only 65% of their mean in those years.  By comparison DC had 2 above average winters and averaged 72% of normal.  I am not saying DC should be throwing a victory party but the numbers don't show any advantage in this pattern for NYC.  It's generally not a great look for them either.  New England....now that's another story. 

That’s pretty compelling. Only one (-PDO, cold ENSO, -QBO, low solar) year out of 14 had above normal snowfall for NYC. Wow. That blows a huge hole in the argument we keep seeing that -QBO/low solar = snowy winter for NYC

[psuhoffman]

1 hour ago, Bob Chill said:

Yea, no surprise the big -nao years paint the picture of at least "cold enough to snow". We don't need a big giant block parked for months on end either. Tendencies and storm track play a big role. The current seasonals show high heights in the 50/50 region. We know exactly how that plays out. Predominant NW storm track with cold shots coming on the heels of rain storms. The EPO can buck that trend with cold air moving through in a progressive pattern (ala 13-14/14-15). On the other hand, we can get a good -AO/NAO has have it get totally fooked by the pac (ala 12-13). 

Mixed signals this season are to our advantage. There won't be much hype one way or the other leading in. Just pointing out possibilities and seeing how it breaks over time. It's crazy how fast time is moving. We're less than 2 months away from early Dec showing on the ensembles. Please let there be a big red ball over the pole....lol

Agree 100%

[Bob Chill]

10 minutes ago, snowman19 said:

That’s pretty compelling. Only one (-PDO, cold ENSO, -QBO, low solar) year out of 14 had above normal snowfall for NYC. Wow. That blows a huge hole in the argument we keep seeing that -QBO/low solar = snowy winter for NYC

If you treat high latitude blocking at the top of the list and not snow it looks pretty good though. Cold enso generally correlates with BN precip in general. I'm going off memory so someone could prove me wrong with a precip composite that shows otherwise but I believe I'm correct. Nina's aren't usually wet winters in the east coast. By default that reduces big snow chances. 

DC climo for total precip in any winter hovers around 11" during DJF and climo snow is 15". The surrounding burbs are generally in the 18-25" range. Using those metrics it's easy to see that the majority of winter precip in the vast majority of winters is rain so that always needs to paid attention to. I don't think NYC is all that much different. Climo precip is probably around the same 11" but snowfall higher in the 25-30" range but the majority of winter precip in NYC is still rain in any winter. 

The thing about cold enso is that big precipitation events in general are not as likely as warm enso. There are exceptions of course but the general rule prevails over longer timescales. 

Why am I pointing this out? Simply because I'll gladly take my chances with a -AO/NAO and QBO/Solar does seem to correlate with that. We probably look at the world different that you guys further north because while we can get massive winters sometimes but we can definitely get more complete dud <10" seasons than we care to remember. Cold enso + -AO/NAO base states most likely keep much of our area out of the <10" seasonal totals. That's the only thing that would make me want to break stuff this winter....finishing the season below 10" SUCKS. Anything above that # is acceptable. Add in some cold air and frozen ponds for skating and I'm even happier. 

[uncle W]

DCA has gotten more snow than NYC about twelve times since 1950...that's about 17% of the time...If I lived in the DCA area I would look at NYC like I look at Boston...sometimes Boston gets beat and NYC gets clobbered...There have been many big storms in DC that weren't that big in NYC...January 1922 is one example...DC got 28" while NYC got 7"...Feb. 6th 2010...DC over 20"...NYC a trace to a few inches in southern parts of the city...That bothers me a lot more than Boston getting more...they are supposed to get more...

[psuhoffman]

26 minutes ago, snowman19 said:

That’s pretty compelling. Only one (-PDO, cold ENSO, -QBO, low solar) year out of 14 had above normal snowfall for NYC. Wow. That blows a huge hole in the argument we keep seeing that -QBO/low solar = snowy winter for NYC

I would have to look to see how strong it is,  but I have seen the correlation between qbo/solar and snowfall.  If you simply look at those three factors it would seem to increase the odds.  But you can't just ignore everything else.  Maybe the PDO/Enso combo reacts to the qbo/solar to offset.  I am not saying the qbo/solar correlation to snowfall isn't true, just that including the other current pattern drivers seems to show no advantage from those two.  Its not a universal, its specific to this pattern. 

[psuhoffman]

22 minutes ago, Bob Chill said:

If you treat high latitude blocking at the top of the list and not snow it looks pretty good though. Cold enso generally correlates with BN precip in general. I'm going off memory so someone could prove me wrong with a precip composite that shows otherwise but I believe I'm correct. Nina's aren't usually wet winters in the east coast. By default that reduces big snow chances. 

DC climo for total precip in any winter hovers around 11" during DJF and climo snow is 15". The surrounding burbs are generally in the 18-25" range. Using those metrics it's easy to see that the majority of winter precip in the vast majority of winters is rain so that always needs to paid attention to. I don't think NYC is all that much different. Climo precip is probably around the same 11" but snowfall higher in the 25-30" range but the majority of winter precip in NYC is still rain in any winter. 

The thing about cold enso is that big precipitation events in general are not as likely as warm enso. There are exceptions of course but the general rule prevails over longer timescales. 

Why am I pointing this out? Simply because I'll gladly take my chances with a -AO/NAO and QBO/Solar does seem to correlate with that. We probably look at the world different that you guys further north because while we can get massive winters sometimes but we can definitely get more complete dud <10" seasons than we care to remember. Cold enso + -AO/NAO base states most likely keep much of our area out of the <10" seasonal totals. That's the only thing that would make me want to break stuff this winter....finishing the season below 10" SUCKS. Anything above that # is acceptable. Add in some cold air and frozen ponds for skating and I'm even happier. 

 

43 minutes ago, snowman19 said:

That’s pretty compelling. Only one (-PDO, cold ENSO, -QBO, low solar) year out of 14 had above normal snowfall for NYC. Wow. That blows a huge hole in the argument we keep seeing that -QBO/low solar = snowy winter for NYC

There have only been 6 low solar -QBO winters that also had cold enso and -PDO since 1950.  NYC finished below average snowfall all 6.  So those betting on solar/qbo to save them in NYC are living dangerously.  That said 6 is a small sample size.  Is it possible that was just bad luck.  Sure... but its enough of a sample to not feel confident solar/qbo alone will help save the winter from other less friendly pattern drivers.  NYC actually averaged more in cold enso/-PDO/-qbo years with high solar.  18.2" vs 16.8" average in years with low solar.  Oddly for our area the average at all 3 airports as well as my location is a small bit higher in low solar vs high solar.  13.9" at DCA vs 9.1".  Again, 6 years is too small to say definitively but perhaps something in this combo of enso/QBO/PDO negates the low solar influence on snowfall. 

[snowman19]

19 minutes ago, Bob Chill said:

If you treat high latitude blocking at the top of the list and not snow it looks pretty good though. Cold enso generally correlates with BN precip in general. I'm going off memory so someone could prove me wrong with a precip composite that shows otherwise but I believe I'm correct. Nina's aren't usually wet winters in the east coast. By default that reduces big snow chances. 

DC climo for total precip in any winter hovers around 11" during DJF and climo snow is 15". The surrounding burbs are generally in the 18-25" range. Using those metrics it's easy to see that the majority of winter precip in the vast majority of winters is rain so that always needs to paid attention to. I don't think NYC is all that much different. Climo precip is probably around the same 11" but snowfall higher in the 25-30" range but the majority of winter precip in NYC is still rain in any winter. 

The thing about cold enso is that big precipitation events in general are not as likely as warm enso. There are exceptions of course but the general rule prevails over longer timescales. 

Why am I pointing this out? Simply because I'll gladly take my chances with a -AO/NAO and QBO/Solar does seem to correlate with that. We probably look at the world different that you guys further north because while we can get massive winters sometimes but we can definitely get more complete dud <10" seasons than we care to remember. Cold enso + -AO/NAO base states most likely keep much of our area out of the <10" seasonal totals. That's the only thing that would make me want to break stuff this winter....finishing the season below 10" SUCKS. Anything above that # is acceptable. Add in some cold air and frozen ponds for skating and I'm even happier. 

La Niña is generally supportive of more clipper and isentropic events rather than a triple phaser, KU monster bombing up the coast, due to the lack of a strong southern stream/STJ adding a lot of energy and moisture to the longwave pattern. El Niño’s are obviously much more inducive for nor’easters  

[mitchnick]

2 minutes ago, snowman19 said:

La Niña is generally supportive of more clipper and isentropic events rather than a triple phaser, KU monster bombing up the coast, due to the lack of a strong southern stream/STJ adding a lot of energy and moisture to the longwave pattern. El Niño’s are obviously much more inducive for nor’easters  

And then there's 95/96 which had a ton of coastals that hit everyone from southern VA to Maine. Yeah, that winter still featured plenty of warmth at times in keeping with the waxing/waning of NINA's, but what a pattern for a NINA and a great winter for most on the entire Board.

[psuhoffman]

54 minutes ago, snowman19 said:

That’s pretty compelling. Only one (-PDO, cold ENSO, -QBO, low solar) year out of 14 had above normal snowfall for NYC. Wow. That blows a huge hole in the argument we keep seeing that -QBO/low solar = snowy winter for NYC

Took a quick look, Since 1950 NYC has had 24 above average snowfall seasons.  Only 3 of them had the combo of -QBO/low solar.  By comparison 4 of them were +QBO/high solar.  The rest were some mix match combo.  Just from that there seems to be no increased likelihood of snow in NYC based on a -QBO/low solar combo regardless of other factors since 1950.  I am not sure where that idea came from, I know there is a statistical correlation between -QBO/Solar and the NAO but not all -NAO result in snow, plus a -NAO in Novermber for instance might factor into that correlation but wouldn't help with snowfall typically.  I am not sure how they got that correlation, but it seems to make the jump and apply it to snowfall lacks merit.  Perhaps because 1996 and 2010, both historic snowfall years, were both -QBO/low solar, the assumption of that combo being good has perpetuated.  But 2003 was a high solar year.  2014 was a positive QBO neutral solar.  The solar/qbo link to snow isn't showing up when I look at the numbers. 

[psuhoffman]

11 minutes ago, mitchnick said:

And then there's 95/96 which had a ton of coastals that hit everyone from southern VA to Maine. Yeah, that winter still featured plenty of warmth at times in keeping with the waxing/waning of NINA's, but what a pattern for a NINA and a great winter for most on the entire Board.

I think God threw that year out there just to give eternal hope to snow weenies every winter. 

[showmethesnow]

2 hours ago, psuhoffman said:

It's my fault, I should have simply included the full year like 1949-50 instead of just 1950.  I was being lazy.  But I used the January of the winter to identify year.  So some of those years are still wrong.  For the winter of 1950 for example, it would be December 1949.  Also, even with the right years I am not sure a mean plot will tell us much because there were such drastically different winters within the analogs.  There are some common threads.  No big HECS storms.  No historically great winters.  But within those goalposts, there was a range from a few total dud non winters to some pretty cold/snowy ones.  The string of years in the 1960s for instance would skew things towards a -NAO since some of those had an off the charts NAO.  That would not mean we are likely to see a -NAO for instance just because the -NAO years were so extreme that it biased the mean in that direction.  I think the data does indicate the NAO is the key here.  If we get NAO help this winter is "likely" to be ok.  If its another positive NAO year were in big trouble.  Once we figure out which way that is likely to go, then we can weed out the positive NAO years and those mean plots would become more useful.  Right now they are getting to a mean by averaging wildly different years together. 

No worries.  

[snowman19]

1 hour ago, mitchnick said:

And then there's 95/96 which had a ton of coastals that hit everyone from southern VA to Maine. Yeah, that winter still featured plenty of warmth at times in keeping with the waxing/waning of NINA's, but what a pattern for a NINA and a great winter for most on the entire Board.

Just a possibility, 95-96 was a 1st year La Niña coming off an El Niño. Is it possibly there was still some Niño lag/hangover that contributed to that pattern? Atmosphere maybe wasn’t totally in “Niña mode” yet? I think this may be why 2nd and 3rd year Ninas tend to behave differently than 1st year Ninas?

[psuhoffman]

56 minutes ago, BTRWx said:

I'm on my way out the door, but I want to propose a Mid Atlantic AmWx project for this winter.  Instead of everyone uploading screenshots from their own data sets, let's develop a group to input and troubleshoot collective data sets!  My one goal this winter will be to collectively produce analogs!  Google Docs anyone? 

I am willing to contribute to whatever system we come up with, but I am not sure if it will work the way you think.  First, not everyone even agrees on what should determine a good analog.  What factors matter and what is just noise.  Then some of those factors change month to month.  Right now I am looking at one set of analogs but by November the PDO could flip and suddenly its a whole new data set.  All of the data is publicly available and just requires taking the time to sort it out.  What could be useful, and this might be what you are suggesting, would be to compile one document that lists all of the indexes for each year all in one place.  Instead of looking up enso and pdo and nao separately.  Maybe that even exists already but if so I have not found it. 

[psuhoffman]

4 minutes ago, snowman19 said:

Just a possibility, 95-96 was a 1st year La Niña coming off an El Niño. Is it possibly there was still some Niño lag/hangover that contributed to that pattern? Atmosphere maybe wasn’t totally in “Niña mode” yet? I think this may be why 2nd and 3rd year Ninas tend to behave differently than 1st year Ninas?

That's certainly possible, its also likely the fact the Nina was weak allowed the NAO/AO/PDO combo to overwhelm the pattern.  Enso is a MAJOR pattern driver and if its going ape its likely to be the dominant factor but if its weak it can be bullied around at times by other factors. 

[snowman19]

59 minutes ago, psuhoffman said:

That's certainly possible, its also likely the fact the Nina was weak allowed the NAO/AO/PDO combo to overwhelm the pattern.  Enso is a MAJOR pattern driver and if its going ape its likely to be the dominant factor but if its weak it can be bullied around at times by other factors. 

Yes. Also remember the 95-96 La Niña was during a +PDO as well, which is an unusual combo 

[ORH_wxman]

2 hours ago, uncle W said:

DCA has gotten more snow than NYC about twelve times since 1950...that's about 17% of the time...If I lived in the DCA area I would look at NYC like I look at Boston...sometimes Boston gets beat and NYC gets clobbered...There have been many big storms in DC that weren't that big in NYC...January 1922 is one example...DC got 28" while NYC got 7"...Feb. 6th 2010...DC over 20"...NYC a trace to a few inches in southern parts of the city...That bothers me a lot more than Boston getting more...they are supposed to get more...

The difference between KDCA and KNYC is less than the difference between KNYC and KBOS. The former gap is like 11" per season and latter is around 17" per season. So it is less unusual to get less snow than DCA.

 

20 hours ago, C.A.P.E. said:

Man that Feb composite has a a Cold and dry look.

It's also a lot colder than I'd expect this winter. It is really hard to get cold in February in the eastern US in La Nina. You probably have to go back to Feb 1972 to get a truly cold February during La Nina...there's some borderline below avg temps in years like Feb 1996 and 1974...and New England had weak below average temps in Feb 2011...but it was warmer than normal south of there. Feb 1985 was cold in the SE but warm in the Northeast...prob around avg near DC.

[RIC_WX]

I definitely see some recent similarities to the 1994-95 winter patter locally and the active, long track tropical season of 1995.  That said, I also feel like stating that places an emphasis on what I might prefer to see and ignores almost every potentially dissimilar data point, and surely they all matter.

I think 95/96 is remembered fondly not just for the frequent and intense bouts of cold and snow, but the fact that when it wasn't cold/snow it was usually sunny and 65*F.  That winter truly had something for everyone.  And it was basically non stop from November 1 right into April.

[BristowWx]

15 minutes ago, RIC_WX said:

I definitely see some recent similarities to the 1994-95 winter patter locally and the active, long track tropical season of 1995.  That said, I also feel like stating that places an emphasis on what I might prefer to see and ignores almost every potentially dissimilar data point, and surely they all matter.

I think 95/96 is remembered fondly not just for the frequent and intense bouts of cold and snow, but the fact that when it wasn't cold/snow it was usually sunny and 65*F.  That winter truly had something for everyone.  And it was basically non stop from November 1 right into April.

I feel like every winter brings us conditions and situations that we weren't expecting or planning for despite some amazing analysis by experts and the like.  In the absence of any strong signal it seems we have as much luck tossing the dice and having each number represent a weather situation as we would be trying to analyze all the possibilities.    

[showmethesnow]

7 hours ago, psuhoffman said:

It's my fault, I should have simply included the full year like 1949-50 instead of just 1950.  I was being lazy.  But I used the January of the winter to identify year.  So some of those years are still wrong.  For the winter of 1950 for example, it would be December 1949.  Also, even with the right years I am not sure a mean plot will tell us much because there were such drastically different winters within the analogs.  There are some common threads.  No big HECS storms.  No historically great winters.  But within those goalposts, there was a range from a few total dud non winters to some pretty cold/snowy ones.  The string of years in the 1960s for instance would skew things towards a -NAO since some of those had an off the charts NAO.  That would not mean we are likely to see a -NAO for instance just because the -NAO years were so extreme that it biased the mean in that direction.  I think the data does indicate the NAO is the key here.  If we get NAO help this winter is "likely" to be ok.  If its another positive NAO year were in big trouble.  Once we figure out which way that is likely to go, then we can weed out the positive NAO years and those mean plots would become more useful.  Right now they are getting to a mean by averaging wildly different years together. 

Now that the confusion over the years is cleared up, fingers crossed, hopefully I now have the correct composites. But as you said until we start narrowing the goal posts these composites are more for entertainment sake then anything else. 

 

Dec-Feb

Dec

Jan

Feb

 

November/March