Weak La Nina Winter

[raindancewx]

One thing I've learned from this thread is the models must all have very different assumptions about how quickly upwelling water reaches the surface, you'd think with the relatively good data since 1950 and especially the 1980s that it would be "resolved" physically, but maybe there is more variation then thought? But it seems pretty clear the CFS is at one extreme on upwelling (it has a -1.3C or so DJF?) and the JAMSTEC/Canadian are at the other extreme (-0.5 to -0.8C?). 

I've also noticed looking through the JAMSTEC data that what they call "Box C" tends to be warmer/colder at a weak, but statistically significant relationship to solar activity (r^2 at 0.05) for the past 86 years or so. My hunch is the Box C warmth really hurts in La Ninas if the trades blow West to East, and the sun seems to favor them being warmer with low sunspot activity (annualized). I have Excel just auto-correlate stuff - was surprised any relationship existed really. 

Box C coordinates: 

Box C

125E-145E, 10S to 20N

 

[dmillz25]

1 hour ago, Stebo said:

Looking at this below, I would disagree

Wouldn't a strong mjo overpower that for a while?

[Stebo]

5 minutes ago, dmillz25 said:

Wouldn't a strong mjo overpower that for a while?

Not if the MJO is in an unfavorable position, positioning of the wave is just as important as strength. As long as the MJO wave can stay out of Phase 7, 8, and 1, then it wouldn't have much if any impact. Some of the longer range projections have the wave decaying into the COD around phase 6.

[dmillz25]

6 minutes ago, Stebo said:

Not if the MJO is in an unfavorable position, positioning of the wave is just as important as strength. As long as the MJO wave can stay out of Phase 7, 8, and 1, then it wouldn't have much if any impact. Some of the longer range projections have the wave decaying into the COD around phase 6.

But if it's strong over phase 6 then yeah correct?

[Stebo]

Just now, dmillz25 said:

But if it's strong over phase 6 then yeah correct?

It can be strong in 6 but still eventually decay into the COD from phase 6 too. If it moves into phase 7 that is where issues can arise.

[dmillz25]

Just now, Stebo said:

It can be strong in 6 but still eventually decay into the COD from phase 6 too. If it moves into phase 7 that is where issues can arise.

Oh ok. Thank you for the explanation 

[Stebo]

Just now, dmillz25 said:

Oh ok. Thank you for the explanation 

I mean we are all talking about model projections, it is far from foolproof, a lot of things can and probably will change too.

[dmillz25]

3 minutes ago, Stebo said:

I mean we are all talking about model projections, it is far from foolproof, a lot of things can and probably will change too.

So if the mjo is in 7 and strong enough it can impact the la niña? Just tryna make sure

[Stebo]

Just now, dmillz25 said:

So if the mjo is in 7 and strong enough it can compact the la niña? Just tryna make sure

If it is strong enough yes, especially if it gets closer to Phase 8.

[dmillz25]

2 minutes ago, Stebo said:

If it is strong enough yes, especially if it gets closer to Phase 8.

Ok gotcha thanks

[raindancewx]

Tropical Tidbits has at least another little bit of warming lately in Nino 3.4, back to -0.2C from -0.4C a day or two ago. October is going to present a major problem to "official" classification at this point as a La Nina, since H1 October is probably -0.2 or -0.3. Second half needs to be -0.7 or -0.8 just to keep the month at -0.5 like September was. The big time cooling in the PDO regions suggests the background state is at least getting more La Nina-y though. Sometimes it seems like Nino 1.2 is the real predictor of the PDO, but that's for another day.

[raindancewx]

European has the warm up we are seeing in Nino 3.4 in October - back to -0.3C or so. Latest run has Nov-Feb in La Nina conditions, most of the ensembles are at a monthly peak warmer than -1.0C, probably -0.7 or so monthly. Very few ensembles have a La Nina (below black line) after February.

[AfewUniversesBelowNormal]

On 9/24/2017 at 8:45 AM, StormchaserChuck said:

 

time sensitive

Bigger -SSTA wave happening now. Nino 3.4 could max out around -1.0 in 2 weeks. 

Hurricane season correlates strongest before the wave(s), not during or after. 

[AfewUniversesBelowNormal]

The timing is, the -SSTA wave will max in 7 days, around Nov 1, then warming possibly all month. One final push in December-January. This will be Weak Nina officially, possibly turning ENSO Neutral for the Spring/Summer

[40/70 Benchmark]

3 hours ago, StormchaserChuck said:

The timing is, the -SSTA wave will max in 7 days, around Nov 1, then warming possibly all month. One final push in December-January. This will be Weak Nina officially, possibly turning ENSO Neutral for the Spring/Summer

Agree.

I just made a blog post a couple of night ago declaring he same thing.

[AfewUniversesBelowNormal]

Subsurface cooling really fast. This could quickly go into Moderate Nina.

[raindancewx]

Will be interesting to see if Nino 3.4 has caught up to the La Nina last year by next week. Still behind as of 10/18. The warm y/y trend has been slowly fading if you animate it though. Suspect the catch up date is around 10/25.

[AfewUniversesBelowNormal]

These are pretty awesome differences in the Hadley Cell areas, both Atlantic and Pacific. My interpretation is that this is a new climate phase, and it looks healthy if that makes any sense. 

(Draw a box 40n-180, 40s-180, 40n-300, 40s-300, blue Nina in middle.

[40/70 Benchmark]

23 hours ago, StormchaserChuck said:

Subsurface cooling really fast. This could quickly go into Moderate Nina.

Regardless of whether or not winter is warm, I, highly doubt we achieve a moderate ONI.

[raindancewx]

Every time this La Nina seems like it wants to be moderate or even strong (like now) some of the warm water from the subtropics seems to drain into the 5S to 5N area and slowly spill west. The big drop to -1.0C now seems like it will be offset in a week or two by the reds (warm waters) building West again.

[AfewUniversesBelowNormal]

^Yup, these will keep it from going strong.

Side note, What an awesome pattern

[raindancewx]

My analog system was able to produce a close match (~80%) to your marked coordinates, hopefully will stay fairly similar in winter. Some of the years are ancient, so you have to imagine an extra 0.2C of warmth in all areas. But this is what I used in my winter outlook that I linked above. It takes into account solar conditions too.

 

[40/70 Benchmark]

15 hours ago, raindancewx said:

Every time this La Nina seems like it wants to be moderate or even strong (like now) some of the warm water from the subtropics seems to drain into the 5S to 5N area and slowly spill west. The big drop to -1.0C now seems like it will be offset in a week or two by the reds (warm waters) building West again.

There is a reason why climo is so emphatic on a weak cold ENSO event at this stage. Warmest JAS ONI of any moderate la nina since 1950 was -0.7, and the JAS ONI for 2017 was -0.1.

I understand that the relatively modest sample size negates the value a bit, but a weak event has been pretty obvious for a few weeks now IMHO.

Again, I could be wrong, as I would defer to the two of you on most things ENSO.

Just the way that I see it.

 

By the way, great long range call on the weak la nina back in May, Chuck...I was originally thinking weak el nino...which would have been orgasmic.

[40/70 Benchmark]

On ‎10‎/‎9‎/‎2017 at 6:50 PM, raindancewx said:

 Weekly        Nino 1.2      Nino 3      Nino 3.4     Nino 4 
 06SEP2017     20.4-0.1     24.3-0.6     26.2-0.6     28.7 0.1
 13SEP2017     19.7-0.7     24.0-0.9     26.1-0.6     28.7 0.0
 20SEP2017     19.3-1.1     23.9-1.0     26.3-0.4     28.7 0.0
 27SEP2017     19.5-1.0     24.4-0.5     26.5-0.2     28.4-0.2
 04OCT2017     19.3-1.4     24.7-0.2     26.7 0.0     28.7 0.1

Could you please link me to that tabular output?

TIA.

[40/70 Benchmark]

I'm seeing some posts intimating that the sea surface temperature anomalies are not accurately depicting how strongly this particular la nina is manifesting itself into the atmosphere. While I'm sure that there is some validity to that, as is often the case, the AS bimonthly MEI value, which of course is comprised of a multitude of different variables to measure just that, was a relatively paltry -.449. Just for comparison sake, the 2007 event, which is a moderate event that many of likened this one to, featured a AS MEI value of -1.175.

Perhaps the SO MEI is poised to take a large spike, so we'll see.....but I think we need to be mindful of not exaggerating the magnitude of the ensuing la nina.

[raindancewx]

5 hours ago, 40/70 Benchmark said:

I'm seeing some posts intimating that the sea surface temperature anomalies are not accurately depicting how strongly this particular la nina is manifesting itself into the atmosphere. While I'm sure that there is some validity to that, as is often the case, the AS bimonthly MEI value, which of course is comprised of a multitude of different variables to measure just that, was a relatively paltry -.449. Just for comparison sake, the 2007 event, which is a moderate event that many of likened this one to, featured a AS MEI value of -1.175.

Perhaps the SO MEI is poised to take a large spike, so we'll see.....but I think we need to be mindful of not exaggerating the magnitude of the ensuing la nina.

 27SEP2017     19.5-1.0     24.4-0.5     26.5-0.2     28.4-0.2
 04OCT2017     19.3-1.4     24.7-0.2     26.7 0.0     28.7 0.1
 11OCT2017     19.5-1.3     24.4-0.5     26.2-0.5     28.5-0.1
 18OCT2017     19.5-1.4     23.9-1.1     25.9-0.8     28.3-0.4

http://www.cpc.ncep.noaa.gov/data/indices/wksst8110.for  (link)

The traditional SOI value is approaching +8 for the last 90 days, so in a pressure sense we're pretty close to Nina status. Not sure if ONI is really Nina like yet, with the warm up early in October.

In retrospect, I've realized that none of the strong El Ninos had any kind of El Nino within two Falls of their formation since at least 1930. I sort of knew that in the Spring but the models are usually OK by July when they had an El Nino, but there was a secondary route in the history where a brief warm up in Summer toward El Nino from La Nina goes cold Neutral by Fall. It happened in 1932, which is one of the reasons I like that year.

Big El Ninos --> Next El Nino

1930-->1939-40, 1940-41, 1941-42

1940-41 & 1941-42 (double El Nino) --> 1945-46

1957-58 & 1958-59 (double El Nino) --> 1963-64

1965-66 --> 1968-69

1972-73 ---> 1976-77 & 1977-78

1982-83 --> 1986-87

1991-92 --> 1994-95

1997-98 --> 2002-03

2009-10 --> 2014-15

2014-15, 2015-16 --> at least 2018

[AfewUniversesBelowNormal]

Wow. 

^This is more impressive than some Strong Nina's. 

I think there is a correlation between subsurface-surface disconnect and Polar Blocking, meaning, if a La Nina can't get going on the surface but is very strong underneath, the tendency is for large blocking events to happen at the Poles, like a release of momentum. 

 

[AfewUniversesBelowNormal]

17 minutes ago, Angrysummons said:

dude, enough. there is no correlation. stop talking your book for once.

My ideas, while maybe not always purely scientific, are right 60-65% of the time. 

[40/70 Benchmark]

What book?

[raindancewx]

The La Nina is now warming/weakening again on Tropical Tidbits.

I threw in 2012 as an analog to winter, and sure enough a weird hybrid tropical/cold system, ala Sandy or the Perfect Storm may develop off of the East Coast this week. Should be fun. Atlantic can do some crazy things in late October.