ENSO Discussion

[Front Ranger]

I don't buy this November blast = crap January thing at all. I guess it depends on what you consider "major", but these are the biggest ones on record:

 

1896 (late January arctic intrusion, ridiculously cold March)

1900 (early January cold and snow)

1911 (late December/early January cold and snow

1955 (great winter, including cold in late January/early Feb)

1985 (long fake cold spell in December, torch January)

2006 (cold/snow in January)

2010 (cold spell in late December/early January that was close to awesomeness, late Feb blast)

 

Seems like every winter in our recorded history that had a major cold wave in November had something else later on, and all but one of them had something in January - the only exception was 85-86, but the extended November cold/snow and the December cold more than makes up for that. I guess we've never had a truly epic 1916/1950 type January after a November cold wave, but those kind of Januaries are very rare in the first place. I see no reason why you wouldn't want to see a major blast in November.

Good points. I think SW really, really wants an epic January, so he focuses on a handful of years. To be fair, a warm November in -ENSO years has led to some of the most epic winter periods the PNW has seem, most recently with 2008.

[Deweydog]

Will be lots of hilarious car accident mayhem if it does. Be happy.

Just imagine a Target parking lot and no visible stall striping.

 

That's recipe #3 in the Anarchist's Cookbook.

[Brennan]

I actually tend to agree with Jim on this one (snowwizzard). Our most epic late December/January's had shitty Novembers. 1915, 1949, 1968, 1971, 1988, 1990, 2003, 2008... yeah some of these years weren't incredible, but find a year that featured an arctic blast and snow at SEA in Nov that also featured a top tier blast in the Dec 20-Jan 31 period...

 

Jim is hoping for the big blast in late December through January. If we get a full fledged blast in November, it more than likely means we won't have a top tier December or January... it's just how works here. The atmosphere doesn't like multiple full fledged artic blasts in the PNW in one winter. Anyone can say oh what about November 2006, or 2010. There are exceptions to every rule...

 

I'm also a little confused on the whole PNA discussion between Phil and Jim. I think we're talking apples to oranges. Old PNA and new PNA seem scaled totally different. I don't even think the new PNA is very indicative of PNW troughing. The old PNA basically mirrored the pattern in the PNW. If there was a GOA ridge and PNW trough the PNA was negative, vice versa. Jim's outlook on this is a bit more simplified as opposed to Phils.

 

Jim remember diving into the PNA/PDO and the NP index for hours on end back in the mid 2000s? Miss those days bud.

[ShawniganLake]

Another exception would be November 1996. A wicked Fraser river blast with snow in mid November prior to the late December blizzard.

[Brennan]

Another exception would be November 1996. A wicked Fraser river blast with snow in mid November prior to the late December blizzard.

There was also absolutely nothing in the January-March period that winter. Great first half though. That was a 1/50 year winter for the NW interior and SW BC.

[Phil]

I actually tend to agree with Jim on this one (snowwizzard). Our most epic late December/January's had shitty Novembers. 1915, 1949, 1968, 1971, 1988, 1990, 2003, 2008... yeah some of these years weren't incredible, but find a year that featured an arctic blast and snow at SEA in Nov that also featured a top tier blast in the Dec 20-Jan 31 period...

 

Jim is hoping for the big blast in late December through January. If we get a full fledged blast in November, it more than likely means we won't have a top tier December or January... it's just how s**t works here. The atmosphere doesn't like multiple full fledged artic blasts in the PNW in one winter. Anyone can say oh what about November 2006, or 2010. There are exceptions to every rule...

 

I'm also a little confused on the whole PNA discussion between Phil and Jim. I think we're talking apples to oranges. Old PNA and new PNA seem scaled totally different. I don't even think the new PNA is very indicative of PNW troughing. The old PNA basically mirrored the pattern in the PNW. If there was a GOA ridge and PNW trough the PNA was negative, vice versa. Jim's outlook on this is a bit more simplified as opposed to Phils.

 

Jim remember diving into the PNA/PDO and the NP index for hours on end back in the mid 2000s? Miss those days bud.

The two PNA calculations are fairly similar overall..both are positive for this month. The problem is there really hasn't been much GOA ridging this month. There was a period of EPO blocking/anticyclonic breaking during the first week of the month, but nothing that resembled a -PNA.

 

Sure, a -EPO usually does lead to western troughing, but that's not the same thing as a -PNA. I want to see a -PNA develop in November, because there are no analogs with top-tier January blasts that featured +PNAs in both October and November:

[Brennan]

The two PNA calculations are fairly similar overall..both are positive for this month. The problem is there really hasn't been much GOA ridging this month. There was a period of EPO blocking/anticyclonic breaking during the first week of the month, but nothing that resembled a -PNA.

 

Sure, a -EPO usually does lead to western troughing, but that's not the same thing as a -PNA. I want to see a -PNA develop in November, because there are no analogs with top-tier January blasts that featured +PNAs in both October and November:

The period of -epo blocking you are referring to early in the month was also -pna using the old formula.

 

Jim do you have the link to monthly pna with the old formula back to 1948?

[Phil]

The period of -epo blocking you are referring to early in the month was also -pna using the old formula.

 

Jim do you have the link to monthly pna with the old formula back to 1948?

True, however it was relatively weak, and both calculations will feature a +PNA average for this month, regardless.

 

FWIW, the calculation was changed to better represent the behavioral mode in question. The PNA and EPO are distinct systematic operations, so it makes sense to differentiate their functions to the highest degree possible, IMO.

 

If anything, I'd argue the EPO is a more consequential index for you guys in DJF than the PNA, while the PNA seems to represent more of a "loading pattern", so to speak. Just IMO.

[BLI snowman]

There was also absolutely nothing in the January-March period that winter. Great first half though. That was a 1/50 year winter for the NW interior and SW BC.

 

This would beat any Fraser River event in the last 4-5 years

 

https://www.wunderground.com/history/airport/KBLI/1997/1/25/DailyHistory.html

 

Things have deteriorated mightily in Whatcom County. Even the footnotes back then were generally more interesting than the main course is now.

[BLI snowman]

I actually tend to agree with Jim on this one (snowwizzard). Our most epic late December/January's had shitty Novembers. 1915, 1949, 1968, 1971, 1988, 1990, 2003, 2008... yeah some of these years weren't incredible, but find a year that featured an arctic blast and snow at SEA in Nov that also featured a top tier blast in the Dec 20-Jan 31 period...

 

 

 

1978-79 for sure.

[Phil]

Good points. I think SW really, really wants an epic January, so he focuses on a handful of years. To be fair, a warm November in -ENSO years has led to some of the most epic winter periods the PNW has seem, most recently with 2008.

But didn't 2008/09 have a giant +PNA ridge in January? It's one of the few "good" winters to feature a +PNA in both October and November, but it was technically more of a +NAM driven pattern during the autumn, almost opposite of this year.

 

The -ENSO years with +PNA patterns in both October & November aren't pretty. Seems to occur more frequently in stronger Niñas, including 07/08, 00/01, 99/00, 98/99, 88/89, 74/75, etc. One good winter in there (1988/89) but it's not a very good pattern analog and was a strong Niña. Closest autumnal match in there, pattern wise, would probably be 74/75, with the deep -AO/+PNA, but that was a heavy Niña/-QBO that went +NAM/+EPO for winter. Wouldn't consider that to be very likely this winter.

 

Looking at weaker -ENSO years, additional years pop up, including 1959/60, 1980/81, 1983/84, and 2008/09. However, none of them featured blasts in January, and most didn't have "great" Januaries overall.

 

So, having noted all of this, I think it's safe to conclude that -ENSO years with +PNA Octobers led to better overall winters when November observed a flip to -PNA.

[wx_statman]

But didn't 2008/09 have a giant +PNA ridge in January? It's one of the few "good" winters to feature a +PNA in both October and November, but it was technically more of a +NAM driven pattern during the autumn, almost opposite of this year.

 

The -ENSO years with +PNA patterns in both October & November aren't pretty. Seems to occur more frequently in stronger Niñas, including 07/08, 00/01, 99/00, 98/99, 88/89, 74/75, etc. One good winter in there (1988/89) but it's not a very good pattern analog and was a strong Niña. Closest autumnal match in there, pattern wise, would probably be 74/75, with the deep -AO/+PNA, but that was a heavy Niña/-QBO that went +NAM/+EPO for winter. Wouldn't consider that to be very likely this winter.

 

Looking at weaker -ENSO years, additional years pop up, including 1959/60, 1980/81, 1983/84, and 2008/09. However, none of them featured blasts in January, and most weren't "great" winters overall.

 

So, having noted all of this, I think it's safe to conclude that -ENSO years with +PNA Octobers led to better overall winters when November observed a flip to -PNA.

 

Well, just out of those four years I'd say 1959-60, 1983-84, and 2008-09 can be considered good/great by our standards here in the PNW lowlands. Especially by modern standards. 

[wx_statman]

Also, January 1960 was very snowy in the Portland area. January 1984 had an Arctic outbreak, although its effects were modified west of the Cascades. 

[Phil]

Well, just out of those four years I'd say 1959-60, 1983-84, and 2008-09 can be considered good/great by our standards here in the PNW lowlands. Especially by modern standards.

Oops, I meant to type Januaries, not winters. Fixed.

 

Just a bit of a difference there.

[Phil]

I'm working on the compilation of -ENSO years that went from +PNA in October to -PNA in November. So far, much better winters showing up, including some historic ones.

[wx_statman]

Oops, I meant to type Januaries, not winters. Fixed.

 

Just a bit of a difference there.

 

Definitely!

 

I'm of the opinion that we don't need to score in January to have a great winter, anyway. 

[Deweydog]

Definitely!

 

I'm of the opinion that we don't need to score in January to have a great winter, anyway.

January is after Xmas.

 

Bring on spring!

[Phil]

The list of -ENSO/+QBO winters that went from +PNA in October to -PNA in November is a very good one.

 

The list is 1950/51, 1955/56, 1964/65, 1978/79, 1995/96, and 2010/11.

 

Also, the much talked-about 2003/04 also went from a +PNA in October to a -PNA in November, as did some other very good winters that weren't just -ENSO and/or +QBO.

[Phil]

Meanwhile, -ENSO/+QBO years that were -PNA in both October and November include 1961/62, 1966/67, 1971/72, 1973/74, 1975/76, 1985/86, and 2013/14.

[Brennan]

This would beat any Fraser River event in the last 4-5 years

 

https://www.wunderground.com/history/airport/KBLI/1997/1/25/DailyHistory.html

 

Things have deteriorated mightily in Whatcom County. Even the footnotes back then were generally more interesting than the main course is now.

Wow.. never knew about that one. Don't think it made it past NW INTERIOR did it?

[BLI snowman]

Wow.. never knew about that one. Don't think it made it past NW INTERIOR did it?

 

Not by much, SEA had a couple of 34 degree highs from it. 

[Phil]

SOI is back below -10 today. I think October averages at least a solid -5, perhaps something like -7 or -8.

[Deweydog]

SOI is back below -10 today. I think October averages at least a solid -5, perhaps something like -7 or -8.

+PDO, -SOI...

 

We're all set!

[Phil]

+PDO, -SOI...

 

We're all set!

Better hope it continues for another 7 weeks. Otherwise, expect another terrible January.

[Phil]

Looks like we're about to lose the stable Maritime forcing typical of La Niña, and head into an unstable/propagatory (MJO) forcing regime, which will initially resemble an east-based El Niño cell.

 

http://www.atmos.albany.edu/student/ventrice/real_time/timeLon/vp850.anom.30.5S-5N.gif

 

Where we go from there is key. Is this merely a spurt of MJO activity, driven by extratropical forcing/EAMT shift? Or might this either represent a systemic shift in the background state, or alter the systematic background state in some way? My hunch is on the former, but it wouldn't shock me if this indeed does initiate a propagatory/MJO wave, which alters the background state in some way (perhaps towards a broader, more east-based niña Walker Cell).

 

It should be noted that significant perturbations to the PV/polar strat tend to precede an increase in equatorial convection/MJO activity along with a cooling of the tropical tropopause/lower stratosphere. Given the reality of what looks to be a significant early season stratospheric wave breaking event, this sort of behavior might have some precedence.

[wx_statman]

January is after Xmas.

 

Bring on spring!

 

2009-10 was a dream winter then! 

[wx_statman]

Not by much, SEA had a couple of 34 degree highs from it. 

 

I actually remember tracking that cold wave. Embarrass, MN hit -50. Kansas City fell to -14, and they haven't seen a colder reading since. Portland only got some modified outflow...story of that winter down here. Just another disappointment! 

[Deweydog]

2009-10 was a dream winter then!

No snow on Halloween, Thanksgiving or Xmas*.

 

F-

 

*- Heavy frost, though!

[ShawniganLake]

Definitely!

 

I'm of the opinion that we don't need to score in January to have a great winter, anyway.

Cold and snow is just as cold and snowy when it happens in December as when it happens in January.

[wx_statman]

No snow on Halloween, Thanksgiving or Xmas*.

 

F-

 

*- Heavy frost, though!

 

Hmm. 2003-04 came dangerously close to producing snow on all three holidays. Maybe that winter is the real benchmark...

[Deweydog]

Hmm. 2003-04 came dangerously close to producing snow on all three holidays. Maybe that winter is the real benchmark...

I really enjoyed that late fall/early winter.

[wx_statman]

I really enjoyed that late fall/early winter.

 

Likewise. If only late January hadn't slipped through our fingers...

[Front Ranger]

Likewise. If only late January hadn't slipped through our fingers...

I remember that bust well. One of the local weather guys had 3 straight sub-freezing highs on the 7 day forecast, with a couple in the 20s. Seemed too good to be true after what we'd already had, and indeed it was.

[wx_statman]

I remember that bust well. One of the local weather guys had 3 straight sub-freezing highs on the 7 day forecast, with a couple in the 20s. Seemed too good to be true after what we'd already had, and indeed it was.

 

That was a monster of an airmass too. All-time record low in Grand Forks, ND from that one. 

[BLI snowman]

I actually remember tracking that cold wave. Embarrass, MN hit -50. Kansas City fell to -14, and they haven't seen a colder reading since. Portland only got some modified outflow...story of that winter down here. Just another disappointment!

1996-97 was the worst tablescrap winter ever for the Portland area. It felt like we were Michael Moore's malnourished dog.

 

In addition to the November, December, and late January airmasses largely running out of steam south of Snohomish County, you also had the rather top tier mid January airmass in the SW and Rockies which just gave us a glancing blow. And another big near-miss to our east with the historic cold shot in early April, just for good measure.

[snow_wizard]

Cold and snow is just as cold and snowy when it happens in December as when it happens in January.

 

The thing is January cold waves are often deeper and last longer.  I can't believe people are saying they don't care if January gets back on track or not.  The other months just aren't capable of the greatness of January.

[snow_wizard]

I see no reason why you wouldn't want to see a major blast in November.

 

 

It has worked out so well for us the past 30 years with no noteworthy Januaries in that time.  People need to do their homework of what January used to do here.

[snow_wizard]

I actually tend to agree with Jim on this one (snowwizzard). Our most epic late December/January's had shitty Novembers. 1915, 1949, 1968, 1971, 1988, 1990, 2003, 2008... yeah some of these years weren't incredible, but find a year that featured an arctic blast and snow at SEA in Nov that also featured a top tier blast in the Dec 20-Jan 31 period...

 

Jim is hoping for the big blast in late December through January. If we get a full fledged blast in November, it more than likely means we won't have a top tier December or January... it's just how s**t works here. The atmosphere doesn't like multiple full fledged artic blasts in the PNW in one winter. Anyone can say oh what about November 2006, or 2010. There are exceptions to every rule...

 

I'm also a little confused on the whole PNA discussion between Phil and Jim. I think we're talking apples to oranges. Old PNA and new PNA seem scaled totally different. I don't even think the new PNA is very indicative of PNW troughing. The old PNA basically mirrored the pattern in the PNW. If there was a GOA ridge and PNW trough the PNA was negative, vice versa. Jim's outlook on this is a bit more simplified as opposed to Phils.

 

Jim remember diving into the PNA/PDO and the NP index for hours on end back in the mid 2000s? Miss those days bud.

 

For sure!

[TT-SEA]

It has worked out so well for us the past 30 years with no noteworthy Januaries in that time.  People need to do their homework of what January used to do here.

 

We don't control it... take what nature gives you right?

[MossMan]

It has worked out so well for us the past 30 years with no noteworthy Januaries in that time. People need to do their homework of what January used to do here.

I don't care if it's November, December, January, or February...just give me something epic!!