2013-14 MA Winter Disco - 'cause it's never too early.

[HM]

Thanks...though not sure I totally understand your use of parentheses in your post and how it reads, or your 2nd paragraph and what you mean by that...though I was looking at 61-62 earlier and deciding whether it is on the table...

 

Sorry about the confusion. So, I subtract group B from group A to see any tendency on the pattern. Both groups have a similar ENSO profile (warm pool positioning and neutral state). However, group B has a more +PDO look while group A more -PDO. From plotting these, I see that the -PDO group tends to be a little cooler in December and a little warmer in February. It may mean absolutely nothing, however.

 

As for the second point, ENSO regions have steadily warmed over the last several decades (and most SST really). So, if you are interested in configurations and not just a PDO or ENSO number, I recommend changing the base state. Since 1981-2010 is a lot warmer than 1950-1981, older analogs will appear colder throughout. In ESRL, you have to use the "enter range of years and optional minus." So for 1961-62, you would enter, 1962 to 1962 with an optional minus of 1950-1980 or something like that.

[snow.]

Sorry about the confusion. So, I subtract group B from group A to see any tendency on the pattern. Both groups have a similar ENSO profile (warm pool positioning and neutral state). However, group B has a more +PDO look while group A more -PDO. From plotting these, I see that the -PDO group tends to be a little cooler in December and a little warmer in February. It may mean absolutely nothing, however.

 

As for the second point, ENSO regions have steadily warmed over the last several decades (and most SST really). So, if you are interested in configurations and not just a PDO or ENSO number, I recommend changing the base state. Since 1981-2010 is a lot warmer than 1950-1981, older analogs will appear colder throughout. In ESRL, you have to use the "enter range of years and optional minus." So for 1961-62, you would enter, 1962 to 1962 with an optional minus of 1950-1980 or something like that.

 

Thank you...both make sense now...

[HM]

HM,

 

For vortex weakening don't we want a vortex neat the Aleutians (northern Pacific)?   Instead the GEFS ensembles thru 300 hrs are showing above normal heights where we'd like below normal or am I off base?  I remember reading a paper on that with wave 1 and 2 EP flux in it and thought that was what I could take from the paper. 

 

Yes, you want, optimally, an Aleutian Low and subsequent N. Atlantic Ridge for best wave 1. However, if the North Pacific low is further west toward the Ural Mountains, this can do the job as well (but not as effective). The Aleutian High tends to squash upwelling waves through destructive interference.

 

There are a lot of weird exceptions and sometimes a wave 2 can be strong enough to cause effects like a wave 1. In 2008-09, an East PAC ridge was so strong that it upwelled into a wave 2 configuration, causing the SSW in Jan.

 

This year has plenty of ozone, more than most neutral winters but the +QBO, snow cover and general pattern this autumn argue against any appreciable SSW threat. I suppose there's always a late-season opportunity, esp. if the Aleutian Low tries to return later in November / December.

[WinterWxLuvr]

merry christmas

 

http://www.cpc.ncep.noaa.gov/products/people/mchen/CFSv2FCST/monthly/images/CFSv2.NaT2m.20131101.201312.gif

Good.  In two weeks it will look completely different.

[usedtobe]

Yes, you want, optimally, an Aleutian Low and subsequent N. Atlantic Ridge for best wave 1. However, if the North Pacific low is further west toward the Ural Mountains, this can do the job as well (but not as effective). The Aleutian High tends to squash upwelling waves through destructive interference.

 

There are a lot of weird exceptions and sometimes a wave 2 can be strong enough to cause effects like a wave 1. In 2008-09, an East PAC ridge was so strong that it upwelled into a wave 2 configuration, causing the SSW in Jan.

 

This year has plenty of ozone, more than most neutral winters but the +QBO, snow cover and general pattern this autumn argue against any appreciable SSW threat. I suppose there's always a late-season opportunity, esp. if the Aleutian Low tries to return later in November / December.

 

Thanks for the quick answer.  That is pretty much what I thought I remembered but hearing it keeps me from having to chase down the article. 

[HighStakes]

We have seen that Nina or faux Nina, particularly if weak has a -AO in December...doesn't necessarily mean cold...1996 was a torch even with the strong -AO, as there was a huge -PNA and a ridge to our northeast...

 

Not sure how Nina-esque this winter will be....But I can't wait until November 20th to see if there is some intransigent vortex locked up over the EPO region, so I can go warm...in past winters we have know the deal by end of November that December would be a disaster

Well if we know in about three weeks that December will be a disaster we have to hope there is not a long hangover that lasts well into January. It will quickly become the same old story. The pattern change will keep getting pushed back and when it finally arrives it will be much less than advertised and have a very short duration. I may be stating the obvious but it is imperative that when favorable conditions do line up we must cash in.

[Bob Chill]

I started looking at the behavior of the AO during anomalous periods in Nov. Mixed results and tiny data set but there are some fair obs to be made. The charts below cover Nov 1st - Feb 28th. I was too lazy to format the horizontal axis. 

 

1978 was an outright flip to negative. A special year to say the least:

 

 

 

1993 ended up overall mixed on the season with at some periods of a solid -AO:

 

 

 

1994 had a major +AO period from mid Nov - early Dec. The back broke and the AO remained mostly a non-factor until Feb.

 

 

 

2011 was special but not the kind of special we hope for. The AO went nuts in Nov and didn't break down for 70 days. It tried to break down half way through but reloaded:

 

 

 

It's safe to assume that when the index hits +3 or so that there will be a fair period of time before it breaks down. A 30 day period seems probably the most common for late fall anomalous +AO's (I looked at other years too). But it can obviously last much longer. 

 

If the current AO trend verifies as forecasted over the next 2 weeks then we can probably expect the month to go positive door to door. I suppose if it has to happen, entering a pattern like this in early Nov can be viewed as a good thing as opposed to late month. We just have to hope signs start showing that it's going to break down towards late month. If it does then a seasonable or maybe even cold start to Dec is on the table. Especially with a little help from the PAC.

 

 

 

[Bob Chill]

Hard to say if we top +3 with the AO this month. Guidance in the lr is mixed but enough ens members break the 3 mark to at least say the possibility is there. +3 AO's in Nov are not very common. I could only find 6 in the dataset since the 50's: 72, 73, 75, 78, 94, 2011. None of those years are a good analog for many other reasons but they could be a tool for predicting AO behavior at the very least. 

[aldie 22]

I'm fully on board praying for a fluke train....and being happy with mulch accumulations...gotta be a fool reading this board and expecting anything else...blah...winter...

[Amped]

I'm fully on board praying for a fluke train....and being happy with mulch accumulations...gotta be a fool reading this board and expecting anything else...blah...winter...

 

Yeah currently I see no reason to forecast an above average winter. Uncertainty is our only hope and there's enough of it that a decent winter is still possible, just unlikely.

[Sparky]

too many signs for me to understand

You need to be an astrologist to forecast the weather nowadays.

[snow.]

Hard to say if we top +3 with the AO this month. Guidance in the lr is mixed but enough ens members break the 3 mark to at least say the possibility is there. +3 AO's in Nov are not very common. I could only find 6 in the dataset since the 50's: 72, 73, 75, 78, 94, 2011. None of those years are a good analog for many other reasons but they could be a tool for predicting AO behavior at the very least. 

 

Bob...It is becoming clearer that December will likely be warm with a -PNA, a +AO, and a strong Aleutian High....basically the PAC snapping back into what we've seen for a few years now...and there is no reason to doubt it really....there hasn't been something to really shake it and reverse it...namely a Nino...The ensembles and rollovers are all showing it...especially the Aleutian high....The biggest concern showing up is a strong vortex northeast of AK over the Beaufort Sea....I don't think the placement is as bad for us as the Gulf or Bering Strait, but it isn't good either...pretty much negates any benefit an Aleutian high can give us in terms of cold delivery...probably means without a -AO, the whole east torches as long as the configuration is there....so we get a warm October and Warm November, and a bad storm track...I am already anticipating Wes's posts in late November that he doesn't see any real snow possibility for several weeks...

[aldie 22]

All of our indexes are going in the wrong direction

[mitchnick]

All of our indexes are going in the wrong direction

what did a -AO do for us last year?....nothin'

it may or may not be a banner year, but I'll be d@mned if I'm going to follow the indexes as they rarely work for us; plus, BWI's never had 3 winters in a row with <10" and I just don't believe (or maybe, just don't want to believe!) this year will be as bad as the last 2

[mattie g]

Our winters suck unless everything lines up perfectly. If everything lines up the exact opposite of perfect, it's just as bad as two or three things going wrong.

I'm going to stick with the Farmer's Almanac's call of a cold winter until it happens otherwise.

[WinterWxLuvr]

Bob...It is becoming clearer that December will likely be warm with a -PNA, a +AO, and a strong Aleutian High....basically the PAC snapping back into what we've seen for a few years now...and there is no reason to doubt it really....there hasn't been something to really shake it and reverse it...namely a Nino...The ensembles and rollovers are all showing it...especially the Aleutian high....The biggest concern showing up is a strong vortex northeast of AK over the Beaufort Sea....I don't think the placement is as bad for us as the Gulf or Bering Strait, but it isn't good either...pretty much negates any benefit an Aleutian high can give us in terms of cold delivery...probably means without a -AO, the whole east torches as long as the configuration is there....so we get a warm October and Warm November, and a bad storm track...I am already anticipating Wes's posts in late November that he doesn't see any real snow possibility for several weeks...

Likely? Prediction of indices for the month of December which won't be calculated for nearly two months? Likely?

Can you please tell me what that's based on?

[snow.]

Likely? Prediction of indices for the month of December which won't be calculated for nearly two months? Likely?

Can you please tell me what that's based on?

 

I think we can use the word "likely" sometimes....for instance, DCA's 1981-2010 norm is 15.4"...in the past 25 winters we have exceeded it 3 times...or 12% of winters...So I think it is likely we will have a below normal winter......out of the last 40 months, 39 have had a -PDO...so I think it is reasonable to say it is likely to say something will occur that has occurred 98% of time over the period....

[WinterWxLuvr]

I think we can use the word "likely" sometimes....for instance, DCA's 1981-2010 norm is 15.4"...in the past 25 winters we have exceeded it 3 times...or 12% of winters...So I think it is likely we will have a below normal winter......out of the last 40 months, 39 have had a -PDO...so I think it is reasonable to say it is likely to say something will occur that has occurred 98% of time over the period....

I can buy that logic, but your post referenced the AO and the PNA. We don't have those kinds of numbers for those. I'm pretty sure we had a neg PDO last winter too, but a pretty consistent neg AO as well.

[Bob Chill]

Bob...It is becoming clearer that December will likely be warm with a -PNA, a +AO, and a strong Aleutian High....basically the PAC snapping back into what we've seen for a few years now...and there is no reason to doubt it really....there hasn't been something to really shake it and reverse it...namely a Nino...The ensembles and rollovers are all showing it...especially the Aleutian high....The biggest concern showing up is a strong vortex northeast of AK over the Beaufort Sea....I don't think the placement is as bad for us as the Gulf or Bering Strait, but it isn't good either...pretty much negates any benefit an Aleutian high can give us in terms of cold delivery...probably means without a -AO, the whole east torches as long as the configuration is there....so we get a warm October and Warm November, and a bad storm track...I am already anticipating Wes's posts in late November that he doesn't see any real snow possibility for several weeks...

 

It is a little disappointing seeing the conus, pac, and hl pattern setting up like it is right now. I won't deny that. I do take some solace in the fact that the pattern started in late October and not late November. They almost always break down more often than not within a 6  week period. 

 

Stats show that anomalous -pna Novembers have a higher chance at switching positive in Dec but not always of course. It's interesting that 73 and 94 both went from a decent -pna Nov to a +pna Dec. Both of those years are on the big +ao Nov list. 

 

At the very least I doubt Dec will be void of a fair period of seasonable to below temps. We'll just have to wait a few weeks and remain hopeful that things don't drag on and on. 

[Ji]

This winter sucks

[North Balti Zen]

Agreed. Folks have done a great job at making me pre-hate the upcoming winter.

[Bob Chill]

This winter sucks

 

Once the post t-day event unfolds we can await another magical dec 5th event

 

 

 

[WinterWxLuvr]

This winter sucks

I agree.

I was expecting 10-12" of snow by now.

[clskinsfan]

Any thoughts from the red taggers about the todays QBO number. Looks like its down from 13.1 to 11.69. I know some people are calling for the QBO to stay positive through the winter.

 

http://www.esrl.noaa.gov/psd/data/correlation/qbo.data

[Bob Chill]

LR disclaimer aside, 12z gfs displaces the big stationary vortex centered over the NP to the northern park of AK. Extends some ridging into greenland too. The config over the epac and w coast gets shaken up too.

 

This is the first hint I've seen of a re-shuffle from the nasty +AO/-pna regime we're in. I'm sure the model is premature in timing (assuming the pattern flips at all) but there is hope that this ugly setup doesn't persist into Dec. 

[WxUSAF]

LR disclaimer aside, 12z gfs displaces the big stationary vortex centered over the NP to the northern park of AK. Extends some ridging into greenland too. The config over the epac and w coast gets shaken up too.

 

This is the first hint I've seen of a re-shuffle from the nasty +AO/-pna regime we're in. I'm sure the model is premature in timing (assuming the pattern flips at all) but there is hope that this ugly setup doesn't persist into Dec. 

Was going to post something similar. AO looks like it probably goes near neutral at the end of the run with the PV on our side of the globe between the Beaufort Sea and Hudson Bay.  EPO ridging also gets oriented a little better so the mean trough is in the central CONUS rather than over the west coast.  

 

 I'd like to see if the GEFS and/or Euro show something similar.  Yesterday's GEFS did show the AO trending back toward neutral after mid-month.  As you and others have pointed out, entrenched patterns like a +2-3SD AO usually last longer and a pattern change often shows up too soon on the models.  Still, it'd be nice to see some signs of a pattern change at Day 11-15, even if it stays at Day 11-15 for another 4-6 days.  Perhaps this is that first sign.  

[Bob Chill]

Was going to post something similar. AO looks like it probably goes near neutral at the end of the run with the PV on our side of the globe between the Beaufort Sea and Hudson Bay.  EPO ridging also gets oriented a little better so the mean trough is in the central CONUS rather than over the west coast.  

 

 I'd like to see if the GEFS and/or Euro show something similar.  Yesterday's GEFS did show the AO trending back toward neutral after mid-month.  As you and others have pointed out, entrenched patterns like a +2-3SD AO usually last longer and a pattern change often shows up too soon on the models.  Still, it'd be nice to see some signs of a pattern change at Day 11-15, even if it stays at Day 11-15 for another 4-6 days.  Perhaps this is that first sign.  

 

Early season +AO's seem to break down faster than ones in the meat of winter. Not really a lot of data to make solid conclusions but enough to point towards a 30-45 day period being more likely than 45-60 that we see in the DJF timeframe. The current +AO regime is already 15 days old. It would be an unusual start to winter if the main PV is on our side of the globe to start met Winter. Russia has been a pv magnet in Dec for I don't know how many years now. 

 

I suppose the biggest worry is a full on reload into Dec. It's becoming more important to pay attention to changes in fantasy land now. I like doing it. In a sick way it's fun. lol

[WxUSAF]

DT honking big time about the October snowcover numbers.  I guess end-of-month Eurasia snowcover came in 4th highest on record?  He claims this shoots the "SAI still isn't good" idea out of the water.  I still don't agree with that necessarily.  Seems like he's been hinting for awhile now that he's going to go fairly snowy/cold in his winter forecast.  

[WinterWxLuvr]

DT honking big time about the October snowcover numbers.  I guess end-of-month Eurasia snowcover came in 4th highest on record?  He claims this shoots the "SAI still isn't good" idea out of the water.  I still don't agree with that necessarily.  Seems like he's been hinting for awhile now that he's going to go fairly snowy/cold in his winter forecast.  

I saw a graphic on this forum somewhere in the past couple of days with the snowcover anomalies.  It seemed that most of the higher positive years were decent winters, but that was a very quick glance.

[Bob Chill]

Is it too early to start a thread for winter of 14-15?

 

Latest CPC enso discussion:

 

 

The majority of model forecasts indicate that ENSO-neutral (Niño-3.4 index between -0.5°C and 

0.5°C) will persist into the Northern Hemisphere summer 2014 (Fig. 6). Though confidence is highest for 

ENSO-neutral, there are also growing probabilities for warm conditions (relative to cool conditions) 

toward the spring/summer 2014. The consensus forecast is for ENSO-neutral to continue through the 

Northern Hemisphere spring 2014 (see CPC/IRI consensus forecast). 

 

 

 

Next year is gonna be ROCKIN'!