Winter 2019-20 Preseason Discussion

[Bob Chill]

3 minutes ago, psuhoffman said:

I've seen data that indicates March might have the highest correlation between the NAO and cold/snow here BUT...that probably is because you need so much to line up to get snow here that late.  That doesn't necessarily mean the NAO influences the pattern more then.,  In 2002 we got NAO help early and allowed us those December snows, then the PAC took over the rest of the winter.  Something similar this year would be acceptable.  

I'm just warming up to the idea that this winter may not be a disaster. When I looked at things in Sept I wasn't impressed at all and figured a dud was on tap. Now that we're transitioning into colder climo it's nice to see there are some things potentially breaking in our favor. Should be fun around here when this impressive Nov cold pattern breaks down and a couple weeks of mild weather shows up on guidance. 

[psuhoffman]

1 hour ago, Bob Chill said:

I'm just warming up to the idea that this winter may not be a disaster. When I looked at things in Sept I wasn't impressed at all and figured a dud was on tap. Now that we're transitioning into colder climo it's nice to see there are some things potentially breaking in our favor. Should be fun around here when this impressive Nov cold pattern breaks down and a couple weeks of mild weather shows up on guidance. 

I’m trying to get my thought typed up but I’m in a very similar place. 2 months ago my thoughts were more pessimistic but some key factors like the PDO, QBO, hints at the MJO base state look to be breaking our way. The AO/NAO looks ambiguous to me but if enough of those other factors go right we can live without a perfect Atlantic at all times. 

[frd]

1 hour ago, Bob Chill said:

I'm just warming up to the idea that this winter may not be a disaster. When I looked at things in Sept I wasn't impressed at all and figured a dud was on tap. Now that we're transitioning into colder climo it's nice to see there are some things potentially breaking in our favor. Should be fun around here when this impressive Nov cold pattern breaks down and a couple weeks of mild weather shows up on guidance. 

Glad to hear you think this winter has potential coming up Bob.

The eventual moderation and warm up will make many feel bummed, but it is a natural process.

Difficult at this time to pin point when we moderate.  Rolling forward the phases and the retrogression hopefully not more than a couple weeks warm up. 

Where  last December we broke records for the MJO being in the wrong phases/very high amplitude this December maybe we continue spending the most time in the colder phases. Certainly it has been going that way to a degree. When the pattern reverts back to more winter-like you have to think we might be in prime time. 

I also read something recently that stated the progression of the PV is ahead of some other analog years that match up and because of that instead of a early Jan severe snow storm, such as what happened a few years ago, we might get pattern in the third week of December after the warm up. Total speculation of course. That speculation of course takes into view the - NAO in December as you mentioned.  

Also, read in the winter of 02-03 we had a SSWE , I never knew that. I know your stance on those and I agree sometimes they mess things up for us. Meanwhile you hear stories on the media that cattle and livestock froze as they stood in parts of Siberia and other locals because that area took the direct hit from the effects of the SSW. A SSW is like going to AC and thinking you are going to win. ha ... 

We have had our share lately regarding globally severe generational winter events taking place in the NH.  I think the odds this winter will present some crazy stuff going down. Heck,  look at Denver recently! Seems the atmosphere is aligning to severe blocks and a convoluted structure.  

Thanks for your thoughts Bob !  Now that you are back we can rock and roll . Cheers !  

 

  

 

     

[frd]

Hmm. interesting just apply some pressure and keep it weak. 

Remember there is talk that the seasonal models may be getting the idea of a + NAO  and a + AO from the forecast of a very strong winter PV this coming winter.  

If that is true, and the PV is weaker instead, we might be a different outcome. 

Read from BAMMWX that SST models and the data from them that goes into the seasonal models ( and also SST ocean modeling in general )  is prone to significant fluctuations regarding accuracy. 

Many  times the forecast for a certain SST -state months out in the future never really verifies well. 

BAMMWX stated they studied this and found only about 19 % of the time was the forecast accurate. I am not sure the details and the specifics, but I found that an eye opener. Wonder how much that data effects the seasonal models? Personally,  I am sure it does,  as the oceans are a huge weather driver. 

 

 

 

 

[Bob Chill]

26 minutes ago, frd said:

Glad to hear you think this winter has potential coming up Bob.

     

Basic stats on enso neutral winters favor sub climo snowfall so that may be tough to overcome. The stark reality here is all ENSO winters favor below normal snowfall except for a mod Nino. I'm not thinking this will be a big winter (yet) although any winter can work out. What worried me in early fall was the potential for another hostile Pac year and god knows when we ever get blocking help again... That risk appears to be declining. 

Based on everything I've looked at it's looking more and more like we won't have a warm door to door winter and I'm starting to like what I see in the npac. I don't make seasonal forecasts but gun to head guess... 10-15" at DCA and somewhere around 20" at places like IAD is what I think is most likely. With the exception of mod Ninos I never have any confidence in anything until Dec starts. That's typically the earliest we'll get a glimpse at what might be the predominant pattern in the conus.

Cruising towards mid Novie and not seeing hostile patterns or glaring problems is never a bad thing. Nov can be brutally deceptive though. If early Dec features a displaced trop PV and extensive ridging centered around the west coast of NA then I'll start to get a little more excited about the potential. The only thing that would deflate me is a strong consolidated +AO to kick off Dec. That's an omen that has proven to be a reliable indication that we're in for some trouble. Sure, we can use 13-14 as an example of defying that type of problem but that year was a statistical anomaly on so many levels...

[psuhoffman]

14 minutes ago, Bob Chill said:

Basic stats on enso neutral winters favor sub climo snowfall so that may be tough to overcome. The stark reality here is all ENSO winters favor below normal snowfall except for a mod Nino. I'm not thinking this will be a big winter (yet) although any winter can work out. What worried me in early fall was the potential for another hostile Pac year and god knows when we ever get blocking help again... That risk appears to be declining. 

Based on everything I've looked at it's looking more and more like we won't have a warm door to door winter and I'm starting to like what I see in the npac. I don't make seasonal forecasts but gun to head guess... 10-15" at DCA and somewhere around 20" at places like IAD is what I think is most likely. With the exception of mod Ninos I never have any confidence in anything until Dec starts. That's typically the earliest we'll get a glimpse at what might be the predominant pattern in the conus.

Cruising towards mid Novie and not seeing hostile patterns or glaring problems is never a bad thing. Nov can be brutally deceptive though. If early Dec features a displaced trop PV and extensive ridging centered around the west coast of NA then I'll start to get a little more excited about the potential. The only thing that would deflate me is a strong consolidated +AO to kick off Dec. That's an omen that has proven to be a reliable indication that we're in for some trouble. Sure, we can use 13-14 as an example of defying that type of problem but that year was a statistical anomaly on so many levels...

One troubling trend...and the reason our odds of having an above avg snowfall winter have gone way down, is the change in climo for a enso neutral winter.  From 1960-1989 6 out of 8 neutral years were above avg snowfall.  But from 1990 to 2019 only 2 out of 9 were above avg.  That sudden flip in outcomes for enso neutral has completely changed our climo.  Going back 100 years Nina years were always crap and moderate nino's were always good.  But neutral years used to be good most of the time and lately they are pretty much just as bad as a nina year.  It is as if we need more and more to line up good to get a good winter compared to 50 years ago.  

That does give me some pause...except I see some signs that a lot of the other influences this year line up in a way that might buck that trend.  I also see some signs that the tropical forcing is behaving more like a modoki nino than a neutral winter and that forcing is more important than the actual SST anomalies.  Its how those anomalies influence the pattern drivers that matters...not the actual SST themselves.  If the forcing is the way we want I could care less what the SST anomalies are.  Also none of the neutral years recently seems to be a good match for the combo of QBO/PDO that we have going into this winter.  But again, the trick is knowing which factors are more important absent dominant enso influences.  

[Bob Chill]

4 minutes ago, psuhoffman said:

One troubling trend...and the reason our odds of having an above avg snowfall winter have gone way down, is the change in climo for a enso neutral winter.  From 1960-1989 6 out of 8 neutral years were above avg snowfall.  But from 1990 to 2019 only 2 out of 9 were above avg. 

That's interesting... My guess is the simple fact that temps are warmer and we're losing on the margins. Could be decrease in seasonal precip but I doubt that's the case. 

[psuhoffman]

@Bob Chill  for example...when I was looking at the QBO for this year the other day, I pulled out the 11 years going back to 1950 that had a somewhat similar QBO trend as this one going into winter.  And there problem is only 2 of those 11 were enso neutral, and both of them were prior to 1990.  Both were snowy winters...but they were during the climo period when enso neutral winters were generally snowy.  So... without having any similar neutral QBO years in the last 30 years to use as a test subject its impossible to know for sure if the same qbo enso neutral would favor less snow now...or if one of the reasons neutral winters haven't been as good is that we havent had that combination lately.  We can guess...but there is just no way to know for sure with such small sample sizes.  The optimist in me wants to believe that maybe the results won't be as good as they were in the 60's and 70s with similar conditions...but still would be better than a "typical" neutral climo now.  But maybe I just don't want to be pessimistic before Winter even starts.  

BTW if we want to ignore all other influences and just feel good...the 4 best matches for a descending QBO year that was at a similar point in the phase change as we are right now...the best 4 matches were 1978-79, 1995-96, 2002-3, and 2004-5.  That isn't a bad analog set.  I think we would all take an average of those 4 years!  Shame the QBO isn't the only thing that matters.  

[40/70 Benchmark]

47 minutes ago, Bob Chill said:

Basic stats on enso neutral winters favor sub climo snowfall so that may be tough to overcome. The stark reality here is all ENSO winters favor below normal snowfall except for a mod Nino. I'm not thinking this will be a big winter (yet) although any winter can work out. What worried me in early fall was the potential for another hostile Pac year and god knows when we ever get blocking help again... That risk appears to be declining. 

Based on everything I've looked at it's looking more and more like we won't have a warm door to door winter and I'm starting to like what I see in the npac. I don't make seasonal forecasts but gun to head guess... 10-15" at DCA and somewhere around 20" at places like IAD is what I think is most likely. With the exception of mod Ninos I never have any confidence in anything until Dec starts. That's typically the earliest we'll get a glimpse at what might be the predominant pattern in the conus.

Cruising towards mid Novie and not seeing hostile patterns or glaring problems is never a bad thing. Nov can be brutally deceptive though. If early Dec features a displaced trop PV and extensive ridging centered around the west coast of NA then I'll start to get a little more excited about the potential. The only thing that would deflate me is a strong consolidated +AO to kick off Dec. That's an omen that has proven to be a reliable indication that we're in for some trouble. Sure, we can use 13-14 as an example of defying that type of problem but that year was a statistical anomaly on so many levels...

Bet on late peaking weak el nino, not neutral.

[Bob Chill]

12 minutes ago, psuhoffman said:

BTW if we want to ignore all other influences and just feel good...the 4 best matches for a descending QBO year that was at a similar point in the phase change as we are right now...the best 4 matches were 1978-79, 1995-96, 2002-3, and 2004-5.  That isn't a bad analog set.  I think we would all take an average of those 4 years!  Shame the QBO isn't the only thing that matters.  

Each year always has a bit of its own personality regardless of all the good and bad signals. Since our winters are so short it can be devastating to end up with a hostile pattern for 4-6 weeks. I'd like to think our base state features a pattern that isn't a shutout in general. I really hate when there's literally no chance for weeks on end. The most reliable indicator for good snowfall (other than enso) is a Dec -AO of at least -1.0 or lower. Data shows that -1.2 or lower is like an 80% chance of at or above snowfall. The streak of big +AOs has to end eventually. We haven't had a neg AO in Dec since 2012 and it didn't even matter that year because the Pac decimated our hopes and dreams. All the -AO did was deliver Pac maritime air out of Canada. lol.  

[psuhoffman]

2 minutes ago, 40/70 Benchmark said:

Bet on late peaking weak el nino, not neutral.

2004-5 is a pretty good match if we include weak central pac ninos. 

[40/70 Benchmark]

28 minutes ago, psuhoffman said:

One troubling trend...and the reason our odds of having an above avg snowfall winter have gone way down, is the change in climo for a enso neutral winter.  From 1960-1989 6 out of 8 neutral years were above avg snowfall.  But from 1990 to 2019 only 2 out of 9 were above avg.  That sudden flip in outcomes for enso neutral has completely changed our climo.  Going back 100 years Nina years were always crap and moderate nino's were always good.  But neutral years used to be good most of the time and lately they are pretty much just as bad as a nina year.  It is as if we need more and more to line up good to get a good winter compared to 50 years ago.  

That does give me some pause...except I see some signs that a lot of the other influences this year line up in a way that might buck that trend.  I also see some signs that the tropical forcing is behaving more like a modoki nino than a neutral winter and that forcing is more important than the actual SST anomalies.  Its how those anomalies influence the pattern drivers that matters...not the actual SST themselves.  If the forcing is the way we want I could care less what the SST anomalies are.  Also none of the neutral years recently seems to be a good match for the combo of QBO/PDO that we have going into this winter.  But again, the trick is knowing which factors are more important absent dominant enso influences.  

SOI and subsurface all supportive of weak el nino...which is why ocean has been responding. Writing about that now in outlook.

[40/70 Benchmark]

Just now, psuhoffman said:

2004-5 is a pretty good match if we include weak central pac ninos. 

Good analog, but not my number one. Later onset should have ramifications this season.

[40/70 Benchmark]

I think this warm ENSO event will end up central based, like last year and 2005. Warmth is progressing east and Japanese guidance supports a continuation of this.

[psuhoffman]

14 minutes ago, 40/70 Benchmark said:

SOI and subsurface all supportive of weak el nino...which is why ocean has been responding. Writing about that now in outlook.

Can't wait to read it.  

[MillvilleWx]

4 hours ago, psuhoffman said:

Can't wait to read it.  

I second this

[Maestrobjwa]

4 hours ago, 40/70 Benchmark said:

SOI and subsurface all supportive of weak el nino...which is why ocean has been responding. Writing about that now in outlook.

Now last year this was a problem, correct?

[40/70 Benchmark]

51 minutes ago, Maestrobjwa said:

Now last year this was a problem, correct?

The problem last year was that atmosphere didn't respond to the ocean....there was no coupling until very late season.

[yoda]

1 hour ago, MillvilleWx said:

I second this

I third this

[Maestrobjwa]

20 minutes ago, 40/70 Benchmark said:

The problem last year was that atmosphere didn't respond to the ocean....there was no coupling until very late season.

Ah I see...any indication if things will couple this year? (I know it's just one factor out of many...but just wondering)

[frd]

Wow,  this is a huge surprise,  and then again not so surprised.   

I value your research and insights, thanks for the time in putting this together @Isotherm

Personally I feel we do a generally normal winter but we can revisit this in later March. 

Isotherm's Winter Forecast 

http://www.lightinthestorm.com/

 

[40/70 Benchmark]

11 minutes ago, Maestrobjwa said:

Ah I see...any indication if things will couple this year? (I know it's just one factor out of many...but just wondering)

I think more for the second half...

[frd]

Well......... deja vu anyone 

Just like last year to the date per Bluewave , ( record high NA/NH snow cover )  wonder if we face the same scenario as Dec 2018 come this mid December,  when the NH snow cover dropped rapidly. What looked so  promising changed so quickly as warmth over spread the land.   

https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

 

 

 

[Maestrobjwa]

1 hour ago, frd said:

Well......... deja vu anyone 

Just like last year to the date per Bluewave , ( record high NA/NH snow cover )  wonder if we face the same scenario as Dec 2018 come this mid December,  when the NH snow cover dropped rapidly. What looked so  promising changed so quickly as warmth over spread the land.   

https://www.star.nesdis.noaa.gov/smcd/emb/snow/HTML/snow_extent_plots.html

 

 

 

This is why I'm wondering if this winter in general is gonna be a mirror image of last year...Again, just one factor, but it seems like I keep hearing a few of the same themes from this time last year (minus high expectations, lol)

[ravensrule]

3 hours ago, frd said:

Wow,  this is a huge surprise,  and then again not so surprised.   

I value your research and insights, thanks for the time in putting this together @Isotherm

Personally I feel we do a generally normal winter but we can revisit this in later March. 

Isotherm's Winter Forecast 

http://www.lightinthestorm.com/

 

I hope he is wrong, but unfortunately he is usually right. 

[Rtd208]

Larry Cosgrove issued his winter outlook on 10/31 on his Facebook page. You will need to scroll down to find it. Also, read his replies to the comments under his post for some more clarification.

https://www.facebook.com/larry.cosgrove

[mattie g]

What I know is this:

No one

has

any

actual

clue

whatdafuq

will

happen,

but plenty of weenies will get their knickers in a twist when the slightest bit of "bad news" is posted.

[frd]

This is an interesting precip signal from the seasonal . 

Wonder how active the Northern Jet will be ? Progressive disturbances, versus, do we ever get upstream blocking to develop. 

Everything last winter either flew by or lacked proper phasing. 

 

 

 

[psuhoffman]

9 hours ago, Maestrobjwa said:

This is why I'm wondering if this winter in general is gonna be a mirror image of last year...Again, just one factor, but it seems like I keep hearing a few of the same themes from this time last year (minus high expectations, lol)

He isn't saying it's going to be like last year, he is saying its going to be much much worse.  

[frd]

Pretty impressive SST anomaly and the waters North of Alaska are still ice free. 

I am beginning to appreciate more and more how climate change is changing the drivers of weather. 

Not only with recent Novembers but even with how storms are tracking in the lower latitudes.  In part from the HC and height field compression .