2021-2022 ENSO

[raindancewx]

One thing I looked at last year was the WPO state in La Nina Octobers and then the following winters. These are "meaningfully" positive or negative WPO years since 1950.

-WPO October La Ninas: 1954, 1974, 1984, 1988, 1995, 1999. You can throw in "near-La Ninas" 1959, 1966, 1967, 1978, 1981, 1996, 2001, 2012 too. It's not a not super common look though. Last year was -1.18 in October. Whether you include the near years or not, the signature is for a cold spot in the interior West (Great Basin). I had a similar look to that, but it the cold was centered SE of where I had it, by TX rather than Utah.

+WPO October La Ninas:  1950, 1955, 1956, 1964, 1970, 1971, 1973, 1983, 1998, 2000, 2005, 2007, 2010, 2011, 2016, 2017. The "near-La Ninas" of 1960, 1961, 1962, 1980 too. The +WPO Octobers have the Southern and Eastern US warm and a tiny cold spot in the Northwest (Montana to WA). It's a essentially a classic -PDO signature.

Assuming the WPO finishes positive this month, will be interesting to see if we go to the latter composite. That's essentially what I forecast for the winter.

[StormchaserChuck!]

What is the WPO? What's it's derivative, the PDO? I didn't get any cutoff lows in Russian in my research. The rollforward/rollbackward +60 days didn't give any significant clues. (Maybe planetary clues?)

[StormchaserChuck!]

WPO runs into the NAO at +15-30 days. The correlation vs atmospheric momentum/random is 0.0. It comes from the PNA at -15-25 days. The atmospheric momentum vs random is like 0.05. 

[GaWx]

 It is a shame (for those who prefer cold E US winters) that there is virtually no correlation of Oct NAO to winter NAO during La Niña because there's a chance for it to be the most -NAO October on record for a non-El Nino (back to 1950), which is currently 2012’s -2.06. For whatever reason, the monthly NAO is often close to double what the dailies average out to. At a minimum, it seems to be at least 1.67 times the daily average. Based on that, this month has a good chance of ending up sub -1.8 and could easily end up sub -2.0 (see GEFS based forecast below).

Here is the link to the monthlies back to 1950:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table

The following Octs were sub -1.7:
1960, 1968, 1980, 1992, 1997, 2002, 2006, and 2012

The subsequent DJF NAO along with ENSO:

1960: +0.3/not El Niño
1968: -1.4/El Niño
1980: +0.7/not El Niño
1992: +0.9/not El Niño
1997: -0.2/El Niño
2002: -0.2/El Niño
2006: +0.4/El Niño
2012: 0.0/not El Niño

 Only one of the 8 subsequent winters had a strong -NAO (1968) and it was El Niño. Two others were slightly -NAO and they were also El Niño. The 4 non-El Niño winters were in the 0.0 to +0.9 range and averaged +0.5. Looking at all 8 winters, they averaged +0.1.

Conclusion: Despite the forecast for Oct of 2021 to have one of, if not THE, most -NAO on record for any Oct, it by no means is predictive of a -NAO this winter. Of course, that doesn’t mean it can’t end up that way. I’m just saying that history says that this month being so strongly -NAO doesn’t mean an increased chance for -NAO this winter vs climo based chances. Furthermore, this winter being La Niña, if anything, reduces the chances based on ENSO climo.

Here’s the impressive GEFS NAO forecast:

[StormchaserChuck!]

We are also going to have the most -PNA on record for Sept-Oct since 1948, by a long shot. Next one is like 0.70/this. (I'm using 500mb). 

I am also going to bring this up... Deepening in the central Nina-subsurface, models will trend much more -PNA in the coming days. 

https://ibb.co/8gYRDsk

[raindancewx]

Going into this winter,one thing I looked at was anti-logs. So this is a La Nina after a La Nina. My idea was what do El Nino after El Nino winters look like, flipped?

I threw out 'three year' El Ninos. This is only second year events of a two year sequence with the sign flipped.

October for El Nino after El Nino years, flipped, are a strong opposite match to this year, which is what you'd expect conceptually. For winter, El Nino after El Nino flipped implies a cold NW US winter. We'll see.

[40/70 Benchmark]

21 hours ago, StormchaserChuck! said:

1988-9 is my favorite analog for legit La Nina. 

Strong la nina with a very positive PNA?

Not sure that is the best seasonal analog..

[40/70 Benchmark]

On 10/11/2021 at 7:32 PM, raindancewx said:

The big drop off in SSTs this week likely is from CPC switching data sources.

For the 1951-2010 period, 26.50C is average in Nino 3.4 We're not 0.5C below that yet on the weeklies. Still running well warm of last year to the east, and somewhat warm of last year in Nino 4.

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf

Starting this week, the weekly sea surface temperature data is based on OISSTv2.1 (Huang et al., 2021). This impacts slides #4-9. The source data is available at this link.

                Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA 
 01SEP2021     20.3-0.2     24.7-0.3     26.5-0.3     28.4-0.3
 08SEP2021     20.7 0.2     24.6-0.3     26.4-0.4     28.5-0.3
 15SEP2021     20.6 0.2     24.3-0.6     26.3-0.4     28.4-0.4
 22SEP2021     20.6 0.2     24.5-0.4     26.4-0.3     28.2-0.5
 29SEP2021     20.5-0.0     25.1 0.3     26.8 0.0     28.2-0.6
 06OCT2021     20.7 0.1     24.7-0.2     26.1-0.7     28.0-0.7

 02SEP2020     18.9-1.7     23.6-1.4     25.8-0.9     28.4-0.4
 09SEP2020     19.5-1.0     23.4-1.4     25.7-1.0     28.5-0.3
 16SEP2020     20.0-0.4     23.6-1.3     25.9-0.8     28.2-0.5
 23SEP2020     19.6-0.8     23.6-1.2     25.7-1.0     28.1-0.6
 30SEP2020     20.1-0.4     23.8-1.1     25.6-1.1     27.9-0.8
 07OCT2020     19.5-1.1     23.4-1.5     25.5-1.2     27.8-0.9

I am not finding the weekly data here...maybe it has to do with the outage. Could someone please send the link directly to the data?

Thanks.

[GaWx]

7 hours ago, 40/70 Benchmark said:

I am not finding the weekly data here...maybe it has to do with the outage. Could someone please send the link directly to the data?

Thanks.

https://www.cpc.ncep.noaa.gov/data/indices/wksst9120.for

- Nino 3.4, is at -0.8 vs -0.6 a week before

- It appears that they've just restated past weeks to reflect on the new dataset. Remember my post about that last week's showing a 0.7 cooling from 0.0 to -0.7? Now last week shows only a 0.1 cooling from -0.5 to -0.6

[40/70 Benchmark]

31 minutes ago, GaWx said:

https://www.cpc.ncep.noaa.gov/data/indices/wksst9120.for

- Nino 3.4, is at -0.8 vs -0.6 a week before

- It appears that they've just restated past weeks to reflect on the new dataset. Remember my post about that last week's showing a 0.7 cooling from 0.0 to -0.7? Now last week shows only a 0.1 cooling from -0.5 to -0.6

Thanks Larry.

Is the MEI v2 database loading for you? Its only letting me get to the overview for some reason.

[GaWx]

55 minutes ago, 40/70 Benchmark said:

Thanks Larry.

Is the MEI v2 database loading for you? Its only letting me get to the overview for some reason.

 I haven’t tried it. Please provide a link.

[raindancewx]

10 hours ago, 40/70 Benchmark said:

Strong la nina with a very positive PNA?

Not sure that is the best seasonal analog..

What are you talking about? https://psl.noaa.gov/data/correlation/pna.data

 1988   0.03   1.37   0.38   1.12   0.61   1.31   1.60  -0.62  -0.97   0.89   0.11   0.33
 1989  -1.57  -1.71  -1.56  -0.77  -0.04  -0.56  -0.59  -0.27   0.41  -1.08  -0.70   0.57

                 Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 01SEP2021     20.7-0.1     24.7-0.2     26.4-0.3     28.4-0.2
 08SEP2021     20.8 0.1     24.7-0.1     26.5-0.2     28.3-0.3
 15SEP2021     20.7-0.0     24.6-0.3     26.4-0.3     28.2-0.4
 22SEP2021     21.1 0.4     24.7-0.2     26.5-0.2     28.2-0.5
 29SEP2021     21.2 0.5     24.8-0.2     26.2-0.5     27.9-0.7
 06OCT2021     20.9 0.1     24.7-0.3     26.1-0.6     27.9-0.7
 13OCT2021     20.7-0.2     24.4-0.7     26.0-0.8     28.1-0.5

I'm on board with the government now - we're at 26.0C. That's cold enough for a La Nina to me. About two months later than last year though. Still running warm of last year each zone. 

 02SEP2020     20.1-0.6     23.9-1.0     26.0-0.7     28.3-0.4
 09SEP2020     19.6-1.1     23.9-1.0     26.1-0.6     28.3-0.3
 16SEP2020     20.0-0.7     24.0-0.9     26.0-0.7     28.2-0.4
 23SEP2020     20.2-0.5     24.0-0.9     25.9-0.8     28.1-0.5
 30SEP2020     19.9-0.8     24.3-0.6     25.9-0.8     27.9-0.7
 07OCT2020     20.0-0.8     24.0-1.0     25.8-0.9     27.9-0.7
 14OCT2020     20.6-0.3     24.0-1.1     25.6-1.2     27.8-0.8

Looks like the Peruvian fishermen will win again. The cooling below the surface looks like it is about to stop. Should translate to coldest readings at the surface in 2-4 weeks after the cooling stops. Then the La Nina begins a slow death. We've been following the 2011 most closely of the years when that data exists. The timing of an imminent reversal (1-3 weeks I think) is on schedule with 2011.

[raindancewx]

Nate Mantua sent out the new PDO value for September today.

2021 PDO Index monthly values:
January   -0.16
February -0.54
March     -1.17
April        -0.91
May        -0.94
June      -1.18
July        -1.87
August   -1.12
September  -1.53
 

Last September was -0.7. Look familiar? Btw, most -PDO for September since 2012. Similar to 9/2011 (-1.79).

 

 

[40/70 Benchmark]

44 minutes ago, raindancewx said:

What are you talking about? https://psl.noaa.gov/data/correlation/pna.data

 1988   0.03   1.37   0.38   1.12   0.61   1.31   1.60  -0.62  -0.97   0.89   0.11   0.33
 1989  -1.57  -1.71  -1.56  -0.77  -0.04  -0.56  -0.59  -0.27   0.41  -1.08  -0.70   0.57

                 Nino1+2      Nino3        Nino34        Nino4
 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA
 01SEP2021     20.7-0.1     24.7-0.2     26.4-0.3     28.4-0.2
 08SEP2021     20.8 0.1     24.7-0.1     26.5-0.2     28.3-0.3
 15SEP2021     20.7-0.0     24.6-0.3     26.4-0.3     28.2-0.4
 22SEP2021     21.1 0.4     24.7-0.2     26.5-0.2     28.2-0.5
 29SEP2021     21.2 0.5     24.8-0.2     26.2-0.5     27.9-0.7
 06OCT2021     20.9 0.1     24.7-0.3     26.1-0.6     27.9-0.7
 13OCT2021     20.7-0.2     24.4-0.7     26.0-0.8     28.1-0.5

I'm on board with the government now - we're at 26.0C. That's cold enough for a La Nina to me. About two months later than last year though. Still running warm of last year each zone. 

 02SEP2020     20.1-0.6     23.9-1.0     26.0-0.7     28.3-0.4
 09SEP2020     19.6-1.1     23.9-1.0     26.1-0.6     28.3-0.3
 16SEP2020     20.0-0.7     24.0-0.9     26.0-0.7     28.2-0.4
 23SEP2020     20.2-0.5     24.0-0.9     25.9-0.8     28.1-0.5
 30SEP2020     19.9-0.8     24.3-0.6     25.9-0.8     27.9-0.7
 07OCT2020     20.0-0.8     24.0-1.0     25.8-0.9     27.9-0.7
 14OCT2020     20.6-0.3     24.0-1.1     25.6-1.2     27.8-0.8

Looks like the Peruvian fishermen will win again. The cooling below the surface looks like it is about to stop. Should translate to coldest readings at the surface in 2-4 weeks after the cooling stops. Then the La Nina begins a slow death. We've been following the 2011 most closely of the years when that data exists. The timing of an imminent reversal (1-3 weeks I think) is on schedule with 2011.

My mistake. I had a bunch of windows open at once and must have looked at the wrong data. I still don't feel its a very viable analog due to the strength of la nina.

[40/70 Benchmark]

1 hour ago, GaWx said:

 I haven’t tried it. Please provide a link.

https://psl.noaa.gov/enso/mei/#data

[GaWx]

26 minutes ago, 40/70 Benchmark said:

https://psl.noaa.gov/enso/mei/#data

Thank you. Yes, it is working. It has -1.4 for AS.

[40/70 Benchmark]

7 hours ago, GaWx said:

Thank you. Yes, it is working. It has -1.4 for AS.

Yea, it's up now.

[raindancewx]

The storm shown in a week or so in the same spot as the one today south of Kamchatka is forecast on some runs to move that damned north Pacific high for a while. That's your mid-Nov pattern change via the Bering Sea Rule if it happens (10/27, +17-21 days for the pattern change). The Kamchatka storm today lines up well with my analogs which had a good snow signal locally around 11/8 (10/20, +17-21 days). Had mentioned mid-Nov for a pattern flip in my outlook from 10/11.

[StormchaserChuck!]

The beginning

https://ibb.co/rdbN76n

[raindancewx]

La Nina or not, no meaningful fires this year out here with the relatively cold/wet Summer. 

I like to speak with farmers and ranchers before I do my forecasts. The state looks somewhat healthier than the drought monitor would imply for vegetation with short-term increases in soil moisture. If you've never left the East, we call this first picture "the night sky".

[OHweather]

I like that the strongest cooling this month has been in regions 1+2 and 3, as 4 warms slightly. Steady cooling in 3.4. A trend towards either a basin wide or east-based La Nina, away from Modoki. The sub-surface loop implies this trend continues in the near future. Staying away from that central Pacific or Modoki La Nina look is a good thing for -NAO prospects this winter...

[raindancewx]

I'm not a huge fan of the bucketing for periods as long as Dec-Mar. A lot of the stronger ENSO events start with one form and then migrate to another. I'm much more interested in the similar start and similar finish v. a similar average look. I liked 2007 last year because it was very cold by Peru initially and then it gradually shifted to become very cold by Nino 4 as the east warmed. If you just looked at the average of 2007-08 you would miss that transition.

Nino 4 is a relevant precipitation indicator in February - it'll be interesting if it's much warmer than last year.

For what it's worth, when Accuweather speaks of the "severe" January or whatever, I think they're going with the TNI tendency (Nino 1.2 v. Nino 4 for stronger warmth/cold). When the TNI is positive, the east tends to be warm in January. TNI was positive last January.

The +TNI years are the Modoki La Nina / East El Nino years, while the -TNI years are the Modoki El Nino / East La Nina years. (+TNI January: 1998, 2012, 2021, -TNI January: 2010, 2014, 2018). Issue is the -TNI years are much more common in El Ninos, and so the -TNI eastern cold is really just dominated by the PDO signal when you have a  -TNI with +PDO, since east La Ninas are less common than Modoki El Ninos. I think there are 10 meaningfully -TNI, cold ENSO Januaries (Jan 1968, 1979, 1981, 1982, 1986, 1997, 2002, 2013, 2014, 2018), and at least 20 in warm ENSO years since 1950, so even with a -TNI in January (which I expect), I don't buy the correlation map below.

https://psl.noaa.gov/data/correlation/tni.data

[40/70 Benchmark]

DM is great to portray the mean aggregate of the cold season...the transitional nuances are reflected in the monthly breakdowns. 

[raindancewx]

Some of the -ENSO Novembers following a +WPO/-NAO October include years like 1960, 1998, 2005 which broadly look like November on the CFS at the moment.

[StormchaserChuck!]

It was a cool Summer here too. Seems that after June, it never went above 90. 

[raindancewx]

Some interesting things happening in the background: -NAO with a +AO. That's not real common.

Still think it's interesting that people think this event is going to catch up to last year at the surface. When is that going to happen? It's not early anymore. There are no big areas of purple like last year to spread out. The development is also opposite of last year, the western zones seem to be warming a bit this year, while they were cooling at this time last year. This is still a relatively basin wide event with a weakness in the middle to me (around 120W).

[StormchaserChuck!]

^ The SH -PDO is pretty interesting (not too many examples of symmetry) 

[raindancewx]

This is probably the simplest way to explain why I'm not in the Modoki La Nina camp. Right now, it is much warmer than last year by Peru. Last year, the cold there shifted West. This year, the body of "less cold" should shift West. The cold below the surface should come up to the east though.

In general, there is a big trend to much more -IOD conditions (warmer near Indonesia, colder east of East Africa), and the -PDO especially - 2-5C colder by the West Coast, warmer east of Japan where the warm tongue is for the -PDO.

[StormchaserChuck!]

I loved AZ.. beautiful state. Watch the models trend more -PNA at Day 15, away from current+PNA

[StormchaserChuck!]

12 minutes ago, raindancewx said:

This is probably the simplest way to explain why I'm not in the Modoki La Nina camp. Right now, it is much warmer than last year by Peru. Last year, the cold there shifted West. This year, the body of "less cold" should shift West. The cold below the surface should come up to the east though.

(map)

In general, there is a big trend to much more -IOD conditions (warmer near Indonesia, colder east of East Africa), and the -PDO especially - 2-5C colder by the West Coast, warmer east of Japan where the warm tongue is for the -PDO.

-NAO