My thoughts about winter

[okie333]

Oh, and add 1917-1918 and 1898-1899 to the mix as double-weighted analogs, in addition 2010-2011 as single-weighted. This is not a joke or a wishcast. A combination of ENSO and solar reasons forms the basis for these additions. Both of these were weak/moderate second-year Niñas in low solar periods. 2010-2011 is added for solar, ENSO, and persistence reasons, but it was borderline strong and a first-year Niña, thus it is single-weighted like my AO/NAO analogs. Also interesting to note is that all of the last 4 winters are analogs.

[Jaguars]

Oh, and add 1917-1918 and 1898-1899 to the mix as double-weighted analogs, in addition 2010-2011 as single-weighted. This is not a joke or a wishcast. A combination of ENSO and solar reasons forms the basis for these additions. Both of these were weak/moderate second-year Niñas in low solar periods. 2010-2011 is added for solar, ENSO, and persistence reasons, but it was borderline strong and a first-year Niña, thus it is single-weighted like my AO/NAO analogs. Also interesting to note is that all of the last 4 winters are analogs.

17-18, freezer box

[icebreaker5221]

17-18, freezer box

Feb 1899 was quite historic as well:

http://en.wikipedia.org/wiki/Great_Blizzard_of_1899

[Harry]

What does 2008-09 have to do with 1966-67? 1966-67 was much weaker -ENSO than 2010-11, that's my point.

Neither was officially declared a Nina if you wanna get technical. Both have similarities with that and the QBO i do believe.

1998 and the following years are bad analogs because that El Niño had such an overwhelming impact on the atmosphere, including the substantial warming of global temperatures/heights it produced, and we were also in much more of a +PDO phase.

I cannot believe anyone would even mention or suggest the 80s or 90s in the same breath as far as good analogs go. But yeah i know we have to go through this every year. And yeah i get his point but i would not call it ballbreaking either as he suggested because as said they are irrelevant and thus analogs i would not even consider despite the NAO stuff.

[ORH_wxman]

Neither was officially declared a Nina if you wanna get technical. Both have similarities with that and the QBO i do believe.

'66-'67 was coming off a strong Nino....'08-'09 was basically a weak 2nd year Nina following a mod/strong Nina. The QBO was quite similar, but that is probably where the comparisons really end.

[Harry]

'66-'67 was coming off a strong Nino....'08-'09 was basically a weak 2nd year Nina following a mod/strong Nina. The QBO was quite similar, but that is probably where the comparisons really end.

Yeah good point about the Nino the winter before 66-67. Around here they were very similar winters. Only thing 08-09 lacked was a big bomb. Both were very snowy ( 08-09 #1 and 66-67 #3) around here. However 66-67 did not get cut so short as 08-09 did but Jan 67 torched big time as well. Give me that same exact blizzard with the same total here and i'll take the torch/Jan 67 again. Truthfully though despite 08-09 being snowier i would still take 66-67 over it.

[Bob Chill]

I posted some of this stuff in the MA form yesterday but figured I would see what others think.

I started taking a look at the 60's. From the basic NAO, PDO, and ENSO there are some hints towards a potentially cooler than normal MA winter. The 60's featured a -NAO / -AO through the majority of the decade:

ENSO was pretty much neg neutral or NINA during the first half of the 60's and the NINA years were 62-63, 64-65, 67-68:

PDO was clearly negative through the entire decade and we may be moving towards a long term -PDO right now:

I took years that featured a -NAO/-AO and at least a neg neutral or true Nina, I came up with the following analogs:

1959-60

1960-61

1962-63

1966-67

1967-68

There are some similarities in the 60's to what we are seeing now. Especially with the PDO and AO/NAO indexes. I don't know nearly enough to elaborate other than there are long term cycles and we appear to be entering a potential long term -PDO / NAO / AO cycle.

Here is the DJF temp composite for the years above:

Interestingly, if you pull each month separately, all 3 are below to much below average in temperature.

Here is the temp composite is you just pull the Nina years during the 60's:

DJF precip was below normal across the NE / MA / MW regardless of what years I pulled. I believe this is caused by a suppressed storm track or inactive STJ and strong blocking.

I don't know enough to say with any confidence that this winter could be similar to what we saw in the 60's but there are at least some indications that shows it's possible.

[okie333]

I posted some of this stuff in the MA form yesterday but figured I would see what others think.

I started taking a look at the 60's. From the basic NAO, PDO, and ENSO there are some hints towards a potentially cooler than normal MA winter. The 60's featured a -NAO / -AO through the majority of the decade:

ENSO was pretty much neg neutral or NINA during the first half of the 60's and the NINA years were 62-63, 64-65, 67-68:

PDO was clearly negative through the entire decade and we may be moving towards a long term -PDO right now:

I took years that featured a -NAO/-AO and at least a neg neutral or true Nina, I came up with the following analogs:

1959-60

1960-61

1962-63

1966-67

1967-68

There are some similarities in the 60's to what we are seeing now. Especially with the PDO and AO/NAO indexes. I don't know nearly enough to elaborate other than there are long term cycles and we appear to be entering a potential long term -PDO / NAO / AO cycle.

Here is the DJF temp composite for the years above:

Interestingly, if you pull each month separately, all 3 are below to much below average in temperature.

Here is the temp composite is you just pull the Nina years during the 60's:

DJF precip was below normal across the NE / MA / MW regardless of what years I pulled. I believe this is caused by a suppressed storm track or inactive STJ and strong blocking.

I don't know enough to say with any confidence that this winter could be similar to what we saw in the 60's but there are at least some indications that shows it's possible.

All I can say about the mid-Atlantic is that 1898-1899 and 2009-2010 are both on my analog list, and one of them (98-99) is double-weighted.

[ORH_wxman]

All I can say about the mid-Atlantic is that 1898-1899 and 2009-2010 are both on my analog list, and one of them (98-99) is double-weighted.

'09-10 had a STJ on 'roids. That is not happening this winter.

[NYsnowlover]

'09-10 had a STJ on 'roids. That is not happening this winter.

But you do think that it will be more active than it was during last winter?

[okie333]

'09-10 had a STJ on 'roids. That is not happening this winter.

True, but I expect it to be stronger than average for a borderline weak/moderate La Niña. IMO the ENSO's main contribution to this winter when all is said and done will be to strengthen the northern jet... this year it's leaving the southern jet alone to do its business.

[ORH_wxman]

True, but I expect it to be stronger than average for a borderline weak/moderate La Niña.

Based on what?

[BethesdaWX]

True, but I expect it to be stronger than average for a borderline weak/moderate La Niña. IMO the ENSO's main contribution to this winter when all is said and done will be to strengthen the northern jet... this year it's leaving the southern jet alone to do its business.

Don't second year La Ninas usually feature a weaker Southern Jet? Though I thought you were referencing the Arctic Oscillation only in which I can agree on that aspect but it isn't all AO related, QBO may have been negative in 2009/10 (Not like what we have now), but I don't see how specifically looking at all parameters you can say the STJ "will" do this/that.

[Bob Chill]

I pulled precip composites for all second year and third year Ninas since 1950. This composite map doesn't really show an active STJ.

I'm not saying that we won't have an active STJ this year but I will say the odds are against it.

[ORH_wxman]

I pulled precip composites for all second year and third year Ninas since 1950. This composite map doesn't really show an active STJ.

I'm not saying that we won't have an active STJ this year but I will say the odds are against it.

Ninas suppress convection in the tropical Pacific so that also weakens the tropical Hadley cell which is responsible for the STJ. In El Ninos, the tropical convection is more plentiful over the Pacific which induces a stronger Hadley cell and in turn produces a stronger STJ.

If we have a La Nina with a lot of convection over the PAC, then you could have a more active STJ, but you'd have to have a good reason to forecast more convection in a place that usually sees less in La Nina.

[WinterWxLuvr]

I pulled precip composites for all second year and third year Ninas since 1950. This composite map doesn't really show an active STJ.

I'm not saying that we won't have an active STJ this year but I will say the odds are against it.

I'd bet that that enhanced precip in the Tn and Oh Valleys is from orographic effects and lake cutters. Not exactly what we need in our region. I swear if we get 08-09 again, I think I'll go nuts.

[Lee]

I pulled precip composites for all second year and third year Ninas since 1950. This composite map doesn't really show an active STJ.

I'm not saying that we won't have an active STJ this year but I will say the odds are against it.

Bob, you left 50-51 out. it was a second year nina. Not that it really makes any difference precip wise, just noticed it wasn't there.

[Bob Chill]

Ninas suppress convection in the tropical Pacific so that also weakens the tropical Hadley cell which is responsible for the STJ. In El Ninos, the tropical convection is more plentiful over the Pacific which induces a stronger Hadley cell and in turn produces a stronger STJ.

If we have a La Nina with a lot of convection over the PAC, then you could have a more active STJ, but you'd have to have a good reason to forecast more convection in a place that usually sees less in La Nina.

Thank you for this. Understanding cause and effects in the tropical pac is probably two levels above my knowledge. I read met's posts about this stuff but I don't grasp the mechanics. If you could point me to a good read or two I would appreciate it.

I'd bet that that enhanced precip in the Tn and Oh Valleys is from orographic effects and lake cutters. Not exactly what we need in our region. I swear if we get 08-09 again, I think I'll go nuts.

Hard to say we have that type of result this winter. If you look at the corresponding AO/NAO indices for the years I used you will see that they are mostly positive. Not a lot of blocking and a typical Nina trough over the west would keep the storm track to our west (and a lot of warm air in the E). I pulled some 500mb composites for 1st and 2nd year Ninas with -AO/NAO and liked what I saw. Definitely not a classic Nina look. If anything, it looked more like a +PNA/-NAO. Relying on the NS to generate snow in the MA isn't all that great though (remember last year....ugh) but the cold may be plentiful this year.

Bob, you left 50-51 out. it was a second year nina. Not that it really makes any difference precip wise, just noticed it wasn't there.

Good catch. My data list started @ 1950 so I missed that one. Probably won't make a difference. One thing I noticed when pulling precip composites is that no matter which way I sliced it, Ninas are typically drier than normal along the EC. There are single year exceptions but for the most part Ninas don't bring heavy precip along the EC. I assume it's the STJ generally being quiet.

[easternsnowman]

Who predicted 09-10 to have the STJ it had and did anyone call for it last year?

[SnowGoose69]

Who predicted 09-10 to have the STJ it had and did anyone call for it last year?

There was little STJ action last winter...the composite precip from Dec-Feb shows a -7 to 9 inch deficit over LA and MS. We had those 2 southern streamer systems that hit OK and MO in a short span but that was just about all for last winter.

[OKpowdah]

Who predicted 09-10 to have the STJ it had and did anyone call for it last year?

Most of the meteorological community was on top of the epic 09-10 season early on. Very clear signs. The only "surprise" was the epic screwage in New England

[easternsnowman]

There was little STJ action last winter...the composite precip from Dec-Feb shows a -7 to 9 inch deficit over LA and MS. We had those 2 southern streamer systems that hit OK and MO in a short span but that was just about all for last winter.

Thanks for the info, we still made out pretty good.

[Bob Chill]

Most of the meteorological community was on top of the epic 09-10 season early on. Very clear signs. The only "surprise" was the epic screwage in New England

09-10 was a Nino so I remember all the mets (and weenies) talking about stormtrack and strong STJ early in the season. Dec 19th and then Feb were just awesome storms. The moisture feed from the STJ was just ridiculous. I love this shot from Feb 3rd:

You can see the STJ connection all the way to 150W just north of the equator. I remember looking at the wv loops thinking that this was going to be a monster.

[usedtobe]

I pulled precip composites for all second year and third year Ninas since 1950. This composite map doesn't really show an active STJ.

I'm not saying that we won't have an active STJ this year but I will say the odds are against it.

Bob,

I ran the seasonal snowfall numbers for dca from HM's negative qbo years in his posted thread and got something like 6 years that got 12-21 inches of snow at DCA and 3 years that got 5-7". Of course nine years is too skimpy a data base to draw any conclusions from. I think the good news is that we probably will see about half of the winter with a naegative ao (at least that's my uneducated guess). The sun still on the low side thought it has gotten to be more active than last year. that and the amo, easterly qbo, negative nao during the summer months and low sea ice probably argue for the nao to average on the negative side during the winter. The big caveat is all the correlations with the nao are still on the low side so there isn't much predictability except during the odd year like 2009-2010 when the nino, easterly qbo and favorable sun made the winter forecast quite a bit easier than normal for this area.

[Bob Chill]

Bob,

I ran the seasonal snowfall numbers for dca from HM's negative qbo years in his posted thread and got something like 6 years that got 12-21 inches of snow at DCA and 3 years that got 5-7". Of course nine years is too skimpy a data base to draw any conclusions from. I think the good news is that we probably will see about half of the winter with a naegative ao (at least that's my uneducated guess). The sun still on the low side thought it has gotten to be more active than last year. that and the amo, easterly qbo, negative nao during the summer months and low sea ice probably argue for the nao to average on the negative side during the winter. The big caveat is all the correlations with the nao are still on the low side so there isn't much predictability except during the odd year like 2009-2010 when the nino, easterly qbo and favorable sun made the winter forecast quite a bit easier than normal for this area.

Yes, I'm not very excited about precip totals this year at all. Nothing really points towards it from what I have looked at. I think the only thing that gives me any confidence whatsoever about normal to slightly above normal snowfall is the fact that we could potentially see extended periods of below normal temps. We don't need above normal precip to get normal or above normal snow. Our battle here in the MA is almost always temps.

In my simpleton analysis of the upcoming winter, I really like the prospects of a much below normal December for temps. Outiside of that I really don't have too much to say.

If the NS dominates storminess then I would think that NE will do quite well. When a NS 850 low needs to jump to the coast we typically get "jumped over" so I'm used to that. Maybe we can cash in on a couple of dynamic 500mb lows like the one that got us good last Jan.

[SoCoWx]

Being as the STJ is being discussed, lets all keep in mind that below normal precip. does not have to imply the same for snowfall.

[okie333]

Ninas suppress convection in the tropical Pacific so that also weakens the tropical Hadley cell which is responsible for the STJ. In El Ninos, the tropical convection is more plentiful over the Pacific which induces a stronger Hadley cell and in turn produces a stronger STJ.

If we have a La Nina with a lot of convection over the PAC, then you could have a more active STJ, but you'd have to have a good reason to forecast more convection in a place that usually sees less in La Nina.

I was waiting for this to actually happen before replying, but here's my reasoning:

That's not a typical Niña MJO... Like I said, when all is said and done the Niña's main impact on this winter will be to strengthen the polar jet, NOT to weaken the southern jet... Could lead to moisture-laden superbombs if phasing happens... a big IF, since phasing requires two storms to coincide in positioning on the streams.

[usedtobe]

Ninas suppress convection in the tropical Pacific so that also weakens the tropical Hadley cell which is responsible for the STJ. In El Ninos, the tropical convection is more plentiful over the Pacific which induces a stronger Hadley cell and in turn produces a stronger STJ.

If we have a La Nina with a lot of convection over the PAC, then you could have a more active STJ, but you'd have to have a good reason to forecast more convection in a place that usually sees less in La Nina.

NInas do suppress convection and are the main modulator of tropical convection. However, the QBO also can modulate convection. An easterly QBO allows fro deeper convection and also seems to play a role in increases convection between 150E and 180.

Title:

On the Relationship Between QBO and Distribution of Tropical Deep Convection Authors:

Geller, M. A.; Liess, S. Affiliation:

AA(School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, United States [email protected]), AB(School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY, United States [email protected]) Publication:

American Geophysical Union, Fall Meeting 2009, abstract #A51H-0213 Publication Date:

12/2009 Origin:

AGU AGU Keywords:

[0300] ATMOSPHERIC COMPOSITION AND STRUCTURE, [3362] ATMOSPHERIC PROCESSES / Stratosphere/troposphere interactions Bibliographic Code:

2009AGUFM.A51H0213G

Abstract

Some recent papers (both observational and modeling analyses) have indicated that the stratospheric quasi-biennial oscillation (QBO) significantly affects the troposphere. Some of the difficulties in these observational studies are properly separating El Niño/Southern Oscillation (ENSO) from QBO influences and some ambiguities in the indicators of tropical deep convection. In this paper, we try to improve on these aspects. We use 21.5 years of detailed tropical Weather State (WS) information from the International Satellite Cloud Climatology Project (ISCCP) to describe an influence of the QBO on tropical deep convection and cirrus clouds. Correlations between monthly indices for the QBO and indices for ENSO, Tropospheric Biennial Oscillation (TBO), and the Pacific Decadal Oscillation (PDO) are taken into account. While tropical deep convection is mostly related to ENSO and the annual cycle, the QBO, independent of ENSO, leads to significantly increased deep convection in the Tropics between 150 and 180 oE as well as over the Subtropics around 120 oW. Cirrus clouds over the Tropical West Indian Ocean and West Atlantic are also increased during the easterly QBO phase. Deep convection between 60 and 90 oE as well as over the Central and East Pacific and over central Australia is significantly reduced. The observed pattern reveals a westward (eastward) shift in the strength of the meridional overturning contributions to the Hadley circulation over the Pacific related to the downward influence of the easterly (westerly) QBO.

The QBO and maybe solar also play a role in modulating the Hadley circulation

http://journals.ametsoc.org/doi/pdf/10.1175/1520-0442%282003%29016%3C2552%3AOTRBTQ%3E2.0.CO%3B2

http://atmosdyn.yonsei.ac.kr/nrl/seminar/Salby%20and%20Callaghan%202007%20JC.pdf

The Collemore article shows how the circulations differ away from the equator during the two QBO phases.

I'm still grappling with exactly how that impacts the Haldey cell and general circulation pattern. I have to go back and read HM's responses in his thread.

[brad1551]

I was waiting for this to actually happen before replying, but here's my reasoning:

That's not a typical Niña MJO... Like I said, when all is said and done the Niña's main impact on this winter will be to strengthen the polar jet, NOT to weaken the southern jet... Could lead to moisture-laden superbombs if phasing happens... a big IF, since phasing requires two storms to coincide in positioning on the streams.

[brad1551]

Amen, you need 2 to Tango. Nicely said!!!