Some Thoughts on the Winter 2021-22 Outlook

[raindancewx]

Does it bug you that October 2011 looks a bit like the actual temperature pattern to date for this month? September kind of does too. I don't actually like it as an analog for US weather, just for how the La Nina has developed at and below the surface. If you buy the CPC stuff it looks cold in the West for at least a little while. Lots of cold coming. My analogs were split on the WPO phase in October, and that's important out here in the fall, but they all have it positive in November. My thing with 2001 is it has a relatively early SSW but had a warm US November which I expect. But following the warm November, the -NAO in December kind of didn't do much for the East in 2001. Similar to last year in that sense. I think Weatherbell and crew have something like a -WPO, -NAO, -AO December look for the East and that's why they have it cold. But the colder ENSO years with that kind of look are not that cold since 2000, it's 2000, 2001, 2005.

Solar stuff I find is mostly important for mountainous areas with weird atmospheric properties. Cold air is dense - and the mountain tops are generally colder than valley bottoms outside of inversion setups. But elevated air is also thin. So I think of it as if we have "thin" cold air - and so the sun impacts cold air more on a mountain in New Mexico than a place like Boston or San Diego or Chicago or Memphis or Jacksonville. I have some proprietary maps on my PC of global cloud patterns by month with statistical signifiers for meaningful changes, and the solar changes do impact cloud patterns globally at pretty remarkable statistical strength. If I remember right the wave-lengths below violet, which is the lowest wave-length color (hence 'ultra violet') vary by 6-8% from the solar minimum to the solar maximum via direct observations.

I've also seen research saying that solar activity directly influences the Indian Monsoon as well as the other monsoon circulations. I've found similar things here.  August is the wetter month in high solar years, July is the wetter month in low solar years. There are then meaningful differences in which parts of the cold season are wettest based on when the monsoon was strongest.

[OHweather]

59 minutes ago, raindancewx said:

Does it bug you that October 2011 looks a bit like the actual temperature pattern to date for this month? September kind of does too. I don't actually like it as an analog for US weather, just for how the La Nina has developed at and below the surface. If you buy the CPC stuff it looks cold in the West for at least a little while. Lots of cold coming. My analogs were split on the WPO phase in October, and that's important out here in the fall, but they all have it positive in November. My thing with 2001 is it has a relatively early SSW but had a warm US November which I expect. But following the warm November, the -NAO in December kind of didn't do much for the East in 2001. Similar to last year in that sense. I think Weatherbell and crew have something like a -WPO, -NAO, -AO December look for the East and that's why they have it cold. But the colder ENSO years with that kind of look are not that cold since 2000, it's 2000, 2001, 2005.

Solar stuff I find is mostly important for mountainous areas with weird atmospheric properties. Cold air is dense - and the mountain tops are generally colder than valley bottoms outside of inversion setups. But elevated air is also thin. So I think of it as if we have "thin" cold air - and so the sun impacts cold air more on a mountain in New Mexico than a place like Boston or San Diego or Chicago or Memphis or Jacksonville. I have some proprietary maps on my PC of global cloud patterns by month with statistical signifiers for meaningful changes, and the solar changes do impact cloud patterns globally at pretty remarkable statistical strength. If I remember right the wave-lengths below violet, which is the lowest wave-length color (hence 'ultra violet') vary by 6-8% from the solar minimum to the solar maximum via direct observations.

I've also seen research saying that solar activity directly influences the Indian Monsoon as well as the other monsoon circulations. I've found similar things here.  August is the wetter month in high solar years, July is the wetter month in low solar years. There are then meaningful differences in which parts of the cold season are wettest based on when the monsoon was strongest.

2011 is one of my analogs, so I do think there are enough similarities to this year to consider it. However, I don't currently see a pattern as perilous as that year:

While Oct 2011 had some similarities over the Pacific, this year will have lower heights out west and higher heights in the east, and won't have as positive of an NAO in October. Then in November 2011, the super +EPO and +NAO took over and ended any chance of sustained winter that year:

I currently don't think this year can go as badly as 2011 went by November...but, it is still something to consider if the +EPO doesn't start relaxing into November. We'll know in a few weeks if we're going the way of 2011 or not. 

[raindancewx]

BAM for comparison. The joke with last winter is it'd be near impossible to be much warmer than December or much colder than February on a national basis. So two thirds of the winter forecast trend are kind of known already on a y/y basis.

 

[40/70 Benchmark]

On 10/5/2021 at 12:19 AM, OHweather said:

It’s still a little early on in the game, but we’re getting to the point where we can start narrowing down what various “pattern drivers” may look like this winter and examine analogs and even some seasonal forecast guidance for clues. 

For those who just want the maps, here are my current thoughts on temperature and precip through the winter. I’m lumping March into winter because it’s a month that can still prove to be productive for snow for many areas, and because many analogs are chilly in March. The detailed write-up with reasoning, analogs, and a look at longer range seasonal models is at the linked blog post (I'm exhausted from uploading the images on there, so I'm only going to upload a part of the post here). I hope to follow up with more focused thoughts in November, time permitting…

 

My guesses on teleconnections:

AO: Solidly negative.

NAO: Near neutral or slightly negative overall, possibly large swings

EPO: Near neutral or slightly negative overall.

PNA: Negative, especially later in winter

A stronger or more central-Pacific La Nina could pose warmer risks, especially in the central and eastern U.S., as would a strong stratospheric PV early in the winter that’s coupled to the troposphere. A quick increase in sunspots could also be a warmer risk. If forcing ends up more focused farther west into the Indian Ocean it’d likely point to a warmer winter.

The La Nina staying weak to moderate and more basin-wide would point to a chillier outcome with more blocking being more likely. A weaker stratospheric polar vortex early in the winter, and tropospheric blocking developing in November, would also point towards a chillier / blockier outcome. Scandinavian or Ural ridging in October or November would also point towards a chillier and blockier direction, as would sufficient tropical forcing occurring east into the Pacific at times.

I expect a very up and down winter, with very cold air frequently available over Canada that occasionally works south into much of the central and eastern CONUS this winter, along with the Northwest. The Southwest will generally be milder with a somewhat weak sub-tropical jet. The southern Plains, Gulf Coast, Southeast and lower mid-Atlantic will probably lean mild due to sharp warm-ups when blocking relaxes and / or the PNA shifts negative, though a couple of periods of EPO-induced cold all the way to the coast are possible. The most persistent cold will be in the northern Rockies and Upper Midwest. The analogs really like the first part of winter (December into January, possibly starting to turn colder in November) for blocking and cold into the central and eastern US (with cold focused more on the northwest in February). The analogs have a -EPO, -NAO, and -PNA pattern in March.

I’m optimistic about snow in the northern Rockies and Pacific Northwest, along with from the Great Lakes and Ohio / Tennessee Valleys into much of the Northeast and New England. Along I-95 from Baltimore to DC and Richmond, events will be rainy at times when blocking relaxes so snow will struggle to reach or exceed normal, though there should be opportunities for wintry weather when blocking is strong enough to suppress the Southeast Ridge.

I do want to post some maps based on the analogs I'm currently rolling with...

 

And FWIW, the analog pattern for October is pretty close to what's modeled this year:

Anyways, the rest of the write-up and a closer examination of the analogs is here:

https://jimsullivanweather.com/2021/10/04/an-exploration-of-cool-enso-winters-and-a-look-at-winter-2021-22/

 

Jim, our conceptualization is pretty similar and I really like what you have done. Would you mind if I used some of your composites (IE La nina binned by intensity and placement) to save myself some leg work? I will of course cite anything that I use, but I just want to make sure that you are okay with it.

[OHweather]

50 minutes ago, 40/70 Benchmark said:

Jim, our conceptualization is pretty similar and I really like what you have done. Would you mind if I used some of your composites (IE La nina binned by intensity and placement) to save myself some leg work? I will of course cite anything that I use, but I just want to make sure that you are okay with it.

Yeah go for it! 

[raindancewx]

Jim Sullivan again for the second half of the video.

[raindancewx]

More from Weather Works.

[OHweather]

The EPS weeklies from yesterday...mid-November into the first half of December there's some cross-polar flow along with a -NAO. The Pacific side is less cooperative, but verbatim it'd be active and chilly enough to be interesting for a lot of the northern US and maybe into the central US at times. If the Pacific pattern ever amped, it could get pretty cold. Interesting run at the least. A lot of members have a weakened stratospheric PV as well. 

[OHweather]

PRETTY SURE this fall is NOT going the way that the fall of 2011 did...

Due to ENSO and QBO similarities, it was necessary to consider it as an analog heading into the fall.

However, that year featured persistent western Indian Ocean forcing, near 60E. That teleconnects to a +EPO in November:

http://www.atmos.albany.edu/facstaff/roundy/waves/ (yes I know you can't click the link on the image)

This year, the forcing is definitely focused closer to the Maritimes, near 110-120E:

That teleconnects to a -EPO in November: 

And the models are obliging, for now. 

While I'm not 100% sure what this winter is yet, I am pretty sure that it's NOT 2011-12 or anything particularly close to it. 

[40/70 Benchmark]

Jim, your final thoughts out later this month?

[OHweather]

1 hour ago, 40/70 Benchmark said:

Jim, your final thoughts out later this month?

I am going to try to get to it the next two weekends...my thoughts on the overall evolution haven't changed drastically yet, though I do want to refine thoughts and put out monthly maps for December-March. I'm moving and starting a new job in early December, which I was not expecting in early October when I promised final thoughts in November lol...but I still want to try to get to it in some fashion the next couple of weeks whenever I can. 

[Mr. Kevin]

22 hours ago, OHweather said:

PRETTY SURE this fall is NOT going the way that the fall of 2011 did...

Due to ENSO and QBO similarities, it was necessary to consider it as an analog heading into the fall.

However, that year featured persistent western Indian Ocean forcing, near 60E. That teleconnects to a +EPO in November:

http://www.atmos.albany.edu/facstaff/roundy/waves/ (yes I know you can't click the link on the image)

This year, the forcing is definitely focused closer to the Maritimes, near 110-120E:

That teleconnects to a -EPO in November: 

And the models are obliging, for now. 

While I'm not 100% sure what this winter is yet, I am pretty sure that it's NOT 2011-12 or anything particularly close to it. 

Hi Jim. I have a question. If that forcing maintains itself in the 110-120E in winter, would we get cold at times or would the forcing have to shift for a colder outcome?

[dmillz25]

16 hours ago, OHweather said:

I am going to try to get to it the next two weekends...my thoughts on the overall evolution haven't changed drastically yet, though I do want to refine thoughts and put out monthly maps for December-March. I'm moving and starting a new job in early December, which I was not expecting in early October when I promised final thoughts in November lol...but I still want to try to get to it in some fashion the next couple of weeks whenever I can. 

Staying in NJ or leaving the state?

[OHweather]

16 hours ago, Mr. Kevin said:

Hi Jim. I have a question. If that forcing maintains itself in the 110-120E in winter, would we get cold at times or would the forcing have to shift for a colder outcome?

Forcing that far west in the middle of winter does turn into a short term warm signal as wavelengths get longer. If there's a lot of blocking it may not get super warm, but it would increase risks for warmth (possibly prolonged) mid-winter with all else being equal...that's why Ninas often start cold then get milder. 

7 hours ago, dmillz25 said:

Staying in NJ or leaving the state?

Moving back to the Cleveland area. Though my few years here have me interested enough in East Coast snow that I'm sure I'll still pay some attention, especially in the mid-long range. 

[Mr. Kevin]

3 hours ago, OHweather said:

Forcing that far west in the middle of winter does turn into a short term warm signal as wavelengths get longer. If there's a lot of blocking it may not get super warm, but it would increase risks for warmth (possibly prolonged) mid-winter with all else being equal...that's why Ninas often start cold then get milder. 

Moving back to the Cleveland area. Though my few years here have me interested enough in East Coast snow that I'm sure I'll still pay some attention, especially in the mid-long range. 

Jim, I'm hoping for either a SSW event to delay real warm weather in winter or the qbo to help with a cold weather signal. Not sure how the -qbo can help us if the forcing stays in the 4,5, and 6 phases all winter, which are warm phases in winter. Trying to be optimistic lol

[40/70 Benchmark]

3 hours ago, Mr. Kevin said:

Jim, I'm hoping for either a SSW event to delay real warm weather in winter or the qbo to help with a cold weather signal. Not sure how the -qbo can help us if the forcing stays in the 4,5, and 6 phases all winter, which are warm phases in winter. Trying to be optimistic lol

-QBO helps by making the PV more susceptible to disregulation.

[Iceresistance]

On 11/7/2021 at 7:12 PM, 40/70 Benchmark said:

-QBO helps by making the PV more susceptible to disregulation.

I can also confirm that this La Nina may have caused the PV to become more unstable & will dive down somewhere in the Northern Hemisphere.

[40/70 Benchmark]

1 minute ago, Iceresistance said:

I can also confirm that this La Nina may have caused the PV to become more unstable & will dive down somewhere in the Northern Hemisphere.

Not anytime soon.

[Iceresistance]

1 minute ago, 40/70 Benchmark said:

Not anytime soon.

More like, later this winter.

[Iceresistance]

Can someone please put out the Analogs for the back-to-back February Cold Waves? (1977 & 1978 for example)

I saw it on an another forum, but I've since lost it.

[40/70 Benchmark]

1 hour ago, Iceresistance said:

More like, later this winter.

Agreed...I favor a split late January/early Feb.

[OHweather]

Yeah at the moment I also don't foresee any sort of early sudden strat warming event...granted, these things aren't very predictable more than a couple - few weeks out (and even then it's often just "hints" until it's closer in). But as long as we don't have a strong / coupled strat and tropospheric PV (like January - March of 2020) it's not necessarily bad on its own. I think the PV will see enough minor disruptions in the coming several weeks to prevent that outcome. 

[Mr. Kevin]

3 hours ago, OHweather said:

Yeah at the moment I also don't foresee any sort of early sudden strat warming event...granted, these things aren't very predictable more than a couple - few weeks out (and even then it's often just "hints" until it's closer in). But as long as we don't have a strong / coupled strat and tropospheric PV (like January - March of 2020) it's not necessarily bad on its own. I think the PV will see enough minor disruptions in the coming several weeks to prevent that outcome. 

Hi Jim. Is the mjo not moving out of IO  into maritime continent for the reason the models are backing out on colder pattern east of rocky mountains? I live in Arkansas and its extremely difficult to get snow and ice in November especially anyways, but I wouldn't complain about early season event if the main months of winter are blowtorches

[uncle W]

8 hours ago, Iceresistance said:

Can someone please put out the Analogs for the back-to-back February Cold Waves? (1977 & 1978 for example)

I saw it on an another forum, but I've since lost it.

2015?...1977 had its last cold wave in early Feb...1978 did have many days with a max below freezing but it never got as cold as 1977...

[uncle W]

winters that had most of the snowfall fall in Dec...then again in Feb or March in NYC...el nino years in red...la nina and neutral in black...2005-06, 2007-08 and 2020-21 were la nina years that had most or all its snow in Dec and Feb...

1958-59...Dec...Mar...13" total

1959-60...Dec...Mar...39" total

1961-62...Dec...Feb...18" total

1966-67...Dec...Feb/Mar...51" total

1967-68...Dec...Mar...20" total...

1968-69...Dec...Feb...30" total...

2005-06...Dec...Feb...40" total...

2007-08...Dec...Feb...12" total...

2009-10...Dec...Feb...51" total...

2020-21...Dec...Feb...39" total...

Two years had snow in November and again in Feb and March...

2012-13...Nov...Feb...26" total...

2018-19...Nov...Mar...21" total...

 

 

 

[raindancewx]

My favorite assessment of the Weather Works outlook.

 

[OHweather]

On 11/9/2021 at 7:06 PM, Mr. Kevin said:

Hi Jim. Is the mjo not moving out of IO  into maritime continent for the reason the models are backing out on colder pattern east of rocky mountains? I live in Arkansas and its extremely difficult to get snow and ice in November especially anyways, but I wouldn't complain about early season event if the main months of winter are blowtorches

It doesn't help that the forcing may pull back west into the Indian Ocean again after mid-November. Just not enough blocking yet for sustained cold. 

[Roger Smith]

I posted earlier that I was expecting a reasonably active winter pattern to develop for the central and eastern US, probably a lot of variability but some hope for wintry scenarios at times. 

Now I'm noticing a distinct resemblance to late autumn of 1981 with these very severe rainstorms we are getting here (in BC) -- Nov 1981 had similar episodes. The late autumn of 2006 was very stormy also but not this wet. So if that gives a nod to 1981-82 as one possible analogue then of course it was in that second tier of good winters below the really outstanding ones; not much happened (in the east) during December as I recall since I was living there in 1981, and there was a large-scale pattern change in the new year, severe cold at times, and one or two coastal storms about which I remember very little, the snow largely missed Ontario where I was situated and while it was very cold at times, the ground was almost bare outside the snow belt. Feb 1982 was dry and cold inland too. There was a resumption of severe winter weather in April for about a week. 

About the severe rainfall event, it has washed out two or three major highways and caused urban mudslides. In Nov 1981 there was a bad situation north of Vancouver on the highway to Whistler where a mountain creek swept away a bridge and several vehicles, since then they redesigned all the bridges so that debris can't block the creeks as happened then. A similar disaster in Oct 2003 a bit further north but that was a heavy rain from a Pacific typhoon remnant and I don't remember the rest of the autumn being very stormy. There is some very mild air getting in from the Pacific now and up to quite a high elevation melting a snowpack that just formed, so the flooding with the 6-8" rainfalls is intensified. Luckily there was a fairly good forecast of this and the highways people closed one highway just before it got over-run by a huge flood -- this is ongoing and it may end up totally obliterating the highway for about a half mile, as a river is now running down one side of the divided highway and the barrier is collecting all the debris as it washes over top of the median. 

Haven't seen a start of a winter season much like this in the 27 years I have lived out west, so the pattern is a bit extreme at the moment. 

[raindancewx]

It looks like 1981 had a major switch from a big time -WPO in November to a pretty +WPO in December. I'd be good with that. Not a real common situation in the past 40 years. 

[40/70 Benchmark]

1981-1982 is aligned pretty closely to my expectations for the NE, though perhaps January and February maybe flipped from that year.