Winter 2020-21 Discussion

[CAPE]

Lets get this (pity) party started.

[CAPE]

CFS has been on a "good" run lately with looks like these. No qualifiers necessary. We all know the deal with long range climate models.

 

[CAPE]

^Easy to imagine how this will go. That EPAC ridge/downstream trough position looks precarious.. but a monster -NAO will save us this time!

I wont bother posting it because it sucks beyond words, but the CanSIPS has the h5 look that will probably be much closer to reality, based on our recent run.

[WxUSAF]

Very Nina-ish precipitation outlook here:

 

 

[CAPE]

Yeah it looks like we are going to have a weak Nina or a cold neutral during winter at this juncture. This is recent stuff, from a few days ago-

https://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-cpc_plume

[CAPE]

12 minutes ago, WxWatcher007 said:

Let’s get another 1899 to walk through that door.

Is something like that even meteorologically possible anymore?

[psuhoffman]

19 hours ago, CAPE said:

^Easy to imagine how this will go. That EPAC ridge/downstream trough position looks precarious.. but a monster -NAO will save us this time!

I wont bother posting it because it sucks beyond words, but the CanSIPS has the h5 look that will probably be much closer to reality, based on our recent run.

It’s hard to be very positive about the pacific. We’ve been in a very Nina ish hostile background state even when the SSTs weren’t that bad across the pacific basin. There has been good discussion and speculation about the SST patterns near the maritime continent and correlated mjo impacts being a cause. But it’s hard to imagine an actual Nina would improve that. The Atlantic side is always the wildcard though. At some point the NAO will go negative again in winter. Anyone holding their breath died a long time ago though. 

[Maestrobjwa]

13 hours ago, psuhoffman said:

It’s hard to be very positive about the pacific. We’ve been in a very Nina ish hostile background state even when the SSTs weren’t that bad across the pacific basin. There has been good discussion and speculation about the SST patterns near the maritime continent and correlated mjo impacts being a cause. But it’s hard to imagine an actual Nina would improve that. The Atlantic side is always the wildcard though. At some point the NAO will go negative again in winter. Anyone holding their breath died a long time ago though. 

So how many more absent -NAO winters can we have before we start to think the absence might be permanent (climate change)? I'd imagine this is the longest we've ever gone?

[CAPE]

3 hours ago, Maestrobjwa said:

So how many more absent -NAO winters can we have before we start to think the absence might be permanent (climate change)? I'd imagine this is the longest we've ever gone?

We only care about the NAO during the winter, so this historical series gives you a good idea of the long term values. NAO has been predominately in the +phase during the winter months over the last 50 years, with generally more instances of strongly positive episodes in winter compared to prior periods.

With the recent unfavorable trends in the Pacific patterns during winter, we might be phucked in the MA for awhile. Go north. None of this stuff matters much relative to cold and snow up in NH.

[psuhoffman]

4 hours ago, Maestrobjwa said:

So how many more absent -NAO winters can we have before we start to think the absence might be permanent (climate change)? I'd imagine this is the longest we've ever gone?

 

3 hours ago, CAPE said:

We only care about the NAO during the winter, so this historical series gives you a good idea of the long term values. NAO has been predominately in the +phase during the winter months over the last 50 years, with generally more instances of strongly positive episodes in winter compared to prior periods.

With the recent unfavorable trends in the Pacific patterns during winter, we might be phucked in the MA for awhile. Go north. None of this stuff matters much relative to cold and snow up in NH.

Cape: there are decadal trends within those even broader periods. From 1904 to 1940 the NAO was predominantly positive. It was more negative from 1940-1972. It’s been in another predominant positive phase since.  Then within those decadal trends there are small scale variations. We are due for both a decadal and or a shorter duration winter phase change.  However predicting the flip is impossible. And I’ve even read speculation the slightly more negative period in the late 90s through 2011 was the phase flip only the NAO is trending more positive overall.  I don’t know if I buy that yet. A few more years of this and I probably would. 

Maestro: wrt the shorter term NAO drought...it’s bad but not quite to unheard of territory. First of all we have had some negative NAO periods fairly recently. January 2016 was actually a really favorable NAO and we were unlucky to only cash in once. Of course it was a jackpot so can’t really complain imo.  March 2017 and 2018 both featured blocking that brought us frozen events. The NAO wasn’t actually awful in 2019...both the pac and atl were just “ok” but we had expected great so it felt like a letdown.  Last year was just a train wreck.  But the positive NAO periods have been so anomalously positive such to hide any negative periods in a seasonal or even sometimes monthly mean  

The other problem is parts of our area (DC/Balt) have been kinda unlucky, making a not so good period seem even worse. 2017 and 2018 actually could have been much better. Not saying they should have been good winters. They were Nina’s (weak though). But some Nina’s (especially east based) can be decent. Those winters featured decent patterns and bad luck with storms missing every which way and dc being a meso scale snow minimum.  2019 was a decent winter but “felt” worse due to expectations. Here is the problem (and I tried to warn about this and got some angry kick back) the large scale weather patterns don’t care about our feeling and perceptions OR our local bad luck. The fact that we missed a lot of chances in an otherwise decent pattern 2017-2019 and felt unsatisfied didn’t change the probabilities. We actually were due for a total due. The kind of winter where the whole east coast suffers. They happen every 7 years or so and there hadn’t been one in a while.  Just because we got unlucky locally recently didn’t change that. It’s like if you strike out with your two best hitters in baseball. That is unlucky but it doesn’t mean the next guy who sucks is now more likely to get a hit. It just means you blew your best chance and your probably screwed. Sometimes we get lucky and a not so good pattern over achieves. You could argue we got a lot of that in 2014-2015.  We just paid the piper! 

[Rhino16]

There’s those 11 years of positive NAO starting 1903 which was probably okay, I don’t think anyone needed snow back then... or maybe they did... they just wouldn’t be sitting on a weather forum complaining about the snowflakes that fell last year which they could count on two hands.

[WxUSAF]

Sobbing 

 

[psuhoffman]

16 minutes ago, WxUSAF said:

Sobbing 

 

It’s what we know about probabilities in a Nina. A couple decent years. A whole lot of crap. A few years about as bad at last year even. Then there is 1996 teasing and giving hope to weenies.  

Ill try to re-create it if I get the time (I lost the data when my hard drive crashed years ago) but I did a weekly Nina case study (took forever) and found that If you actually get a -NAO during a Nina your odds of snow are just as good as a -NAO in any other pattern. Recent history supports that.  We only had 2 brief -NAO periods in 2017 and 2018 but both produced a frozen event. We only got 2 weeks or a -NAO in 2000 and we went on an epic tear.  There are some examples of wasted -NAO in a nino but no more than examples in other enso conditions. The problem was 2 things. A -NAO is much less frequent in a Nina. The typical tropical forcing association with a Nina favors conditions disruptive to blocking. And our chances of snow in non NAO blocking go way down, even more so than normal.  I found warning level snowfalls almost non existent in +NAO regimes during a Nina. 

So this winter turning out well pretty much comes down to needing NAO help. What could go wrong?!

[JakkelWx]

39 minutes ago, WxWatcher007 said:

This year, where everything that COULD go wrong literally HAS gone wrong, has zero chance of producing a serene and uplifting winter. 

I predict that the panic room thread is gonna be created on Labor Day and the reapin' list is gonna be full not 5 minutes later.

[JakkelWx]

Lol. Winter forecasts for 2020-21 are of course, already out on YouTube by the same usual suspects (a la DirectWeather, etc). Surprise surprise, it's the factory default cold/snowy forecast every year brought to you by armchair weather weenies!

[Rhino16]

6 hours ago, WxWatcher007 said:

I have to really bring my A game for a 2020 winter. Strength and conditioning and all.

And your air conditioning, am I right?

[CAPE]

We can get good outcomes in a Nina, even without a -NAO, which is generally not favored in a Nina winter. I would not expect a particularly snowy winter, but the 2 most recent Nina winters did produce some decent snow, relatively speaking, including big snow events for the coastal areas of the MA and NE.

Nina winters can be especially frustrating for the MA, but not an automatic shutout by any means. If the timing had been a tad different, this could have been a more memorable period for a larger area.

[biodhokie]

I will expect nothing and be pleasantly surprised when I get my pity 1" on March 31 2021

[CAPE]

Now is the time for optimism. We get to be all wide-eyed and dopey, trying to convince ourselves that winter really could bring the goods. These are good times. This period will last until about mid November, after which the writing will be on the wall, all hope will be lost, and all that will be left is the race to the Panic Room to get a luxury suite at the Reaper Resort before they are all taken.

[Rhino16]

17 hours ago, CAPE said:

Now is the time for optimism. We get to be all wide-eyed and dopey, trying to convince ourselves that winter really could bring the goods. These are good times. This period will last until about mid November, after which the writing will be on the wall, all hope will be lost, and all that will be left is the race to the Panic Room to get a luxury suite at the Reaper Resort before they are all taken.

Unlike others, this year is so backwards that I an entirely expecting to get more snow than last year.

Just make sure no one buys any snow shovels and other equipment because that makes the snow go away for some reason.

[psuhoffman]

19 hours ago, CAPE said:

Now is the time for optimism. We get to be all wide-eyed and dopey, trying to convince ourselves that winter really could bring the goods. These are good times. This period will last until about mid November, after which the writing will be on the wall, all hope will be lost, and all that will be left is the race to the Panic Room to get a luxury suite at the Reaper Resort before they are all taken.

I haven't done any data digging yet. I’m way too busy and it’s too early. But there are other factors that can portend a “colder” Nina.  QBO phase and whether the Nina is west/east based factor in. NAO is huge but it’s not predictable. If you get a colder variety Nina we usually do “ok”. At least some snow which for us is “ok”. Once in a while you combine a colder Nina type with a rare -NAO and you get 1996. There was another early 1900s Nina that while not as good was an example of lucking into a colder archetype Nina and a -NAO. Or we can get lucky with just a -NAO period like 2000 and score big in that window.  But if you get a warm archetype Nina like 2008/2012 and no NAO help...then you get last year again.

In summary can do well but it’s not the favored outcome. Doesn’t mean we don’t get lucky.  But I doubt anyone’s feeling lucky right now. 

[CAPE]

1 hour ago, psuhoffman said:

I haven't done any data digging yet. I’m way too busy and it’s too early. But there are other factors that can portend a “colder” Nina.  QBO phase and whether the Nina is west/east based factor in. NAO is huge but it’s not predictable. If you get a colder variety Nina we usually do “ok”. At least some snow which for us is “ok”. Once in a while you combine a colder Nina type with a rare -NAO and you get 1996. There was another early 1900s Nina that while not as good was an example of lucking into a colder archetype Nina and a -NAO. Or we can get lucky with just a -NAO period like 2000 and score big in that window.  But if you get a warm archetype Nina like 2008/2012 and no NAO help...then you get last year again.

In summary can do well but it’s not the favored outcome. Doesn’t mean we don’t get lucky.  But I doubt anyone’s feeling lucky right now. 

Most guidance seems to favor a cold neutral or a weak Nina at this point. NOAA did issue an official La Nina watch a few days back, with a 50-55% chance for fall and winter. Probably a decent baseline to start with when you start digging into the historical data and analogs.

QBO looks like it may have hit its negative peak and is heading back towards neutral. If that trend continues into fall that's not a good sign. Pretty sure there is a correlation between a significantly negative QBO during the winter months, and colder temps for the eastern US during a weak Nina.

[JakkelWx]

 

[psuhoffman]

On 7/18/2020 at 11:07 AM, CAPE said:

Most guidance seems to favor a cold neutral or a weak Nina at this point. NOAA did issue an official La Nina watch a few days back, with a 50-55% chance for fall and winter. Probably a decent baseline to start with when you start digging into the historical data and analogs.

QBO looks like it may have hit its negative peak and is heading back towards neutral. If that trend continues into fall that's not a good sign. Pretty sure there is a correlation between a significantly negative QBO during the winter months, and colder temps for the eastern US during a weak Nina.

I know a dropping qbo that’s transitioning to negative correlates to colder. Last year was pretty good wrt qbo but did us no good. We wasted it.  Frankly other than the solar minimum I see nothing that looks favorable att. There is always dumb luck though. 

[CAPE]

6 hours ago, psuhoffman said:

I know a dropping qbo that’s transitioning to negative correlates to colder. Last year was pretty good wrt qbo but did us no good. We wasted it.  Frankly other than the solar minimum I see nothing that looks favorable att. There is always dumb luck though. 

Yes in general, but I am pretty sure I saw somewhere that during a weak Nina, a significantly negative QBO for the winter months mitigated the usual warm departures for the eastern US. I will see if I can find it. Either way, it doesn't look good wrt the QBO, as it appears it will be heading into positive territory going forward.

[CAPE]

Here it is-  From DT at WxRisk..

The context is QBO values from -10 to -20 for DJF.

[psuhoffman]

16 hours ago, CAPE said:

Here it is-  From DT at WxRisk..

The context is QBO values from -10 to -20 for DJF.

Maybe there is a correlation but I would take that product with a whole cup of salt. First of all 1963, 1968, 1982 and 2015 weren’t la Nina’s. 2015 was a weak modoki Nino and the others were neutral.   

[CAPE]

7 hours ago, psuhoffman said:

Maybe there is a correlation but I would take that product with a whole cup of salt. First of all 1963, 1968, 1982 and 2015 weren’t la Nina’s. 2015 was a weak modoki Nino and the others were neutral.   

Probably not worth doing any reanalysis at this point, but maybe he included 'cold' neutral years as well as weak Ninas.

The sensible impact of the QBO generally seems nebulous, unreliable, and likely gets overwhelmed by other factors in reality. Looking at the 30mb trends, it also appears to be moving in the "wrong" direction currently.

[psuhoffman]

3 hours ago, CAPE said:

Probably not worth doing any reanalysis at this point, but maybe he included 'cold' neutral years as well as weak Ninas.

The sensible impact of the QBO generally seems nebulous, unreliable, and likely gets overwhelmed by other factors in reality. Looking at the 30mb trends, it also appears to be moving in the "wrong" direction currently.

Possibly but 2015 was a weak nino and 1982 wasn’t cold neutral it was just neutral. Spent DJF at 0 and JFM at +.1. How much is that chart skewed by those 2 years?  And counting 1963 which never came close to nino status and fell in the middle of a cold -NAO period is dubious at best imo. I think he just made a mistake inputting some years.

Oddly wrt QBO the last 2 cycles failed to ever attain a deeply negative phase.  Perhaps that muted their impact. 

[CAPE]

3 hours ago, psuhoffman said:

Possibly but 2015 was a weak nino and 1982 wasn’t cold neutral it was just neutral. Spent DJF at 0 and JFM at +.1. How much is that chart skewed by those 2 years?  And counting 1963 which never came close to nino status and fell in the middle of a cold -NAO period is dubious at best imo. I think he just made a mistake inputting some years.

Oddly wrt QBO the last 2 cycles failed to ever attain a deeply negative phase.  Perhaps that muted their impact. 

Just looking back at 2017-18, the QBO(u30) was moving into the negative phase in Fall and stayed significantly negative through the winter. That winter was decent wrt cold outbreaks/anomalous cold, at least for Dec and Jan. I think that was technically a moderate Nina, but the QBO influence on the tendency for cold that winter may have been real.

The previous winter, also a Nina, QBO was moving into positive territory and stayed positive, and it was more the typical Nina eastern US torch. Again this is cherry picking one index in isolation, and so it is always difficult to determine the actual impact. The character of the Nina events were quite different between those 2 winters.