2024-2025 La Nina

[GaWx]

14 hours ago, raindancewx said:

We'll see what CPC says, but supposedly record +NAO in August. That's actually a fairly widespread, though not particularly strong, cold signal for the US in Nov-Jan.

https://x.com/WorldClimateSvc/status/1831059382450499794

A lot of deeper blues over the West in December. I'd have to look, but maybe that's how the hurricane and cold air wave thing works in the West. Maybe the +NAO Augusts kill the hurricane season? I've never looked really. -NAO August is probably more common in La Nina if I had to guess.

 If you’re talking about the monthly NAO table that goes back to 1950 and had July at +1.46 (see link below), that won’t be anywhere close to a record high. Based on the dailies, I expect it will most likely be near the +0.4 to +0.6 range with a small chance to be as high as +0.7 to +0.75 or so. It still isn’t out at this very late hour but it could be released later today. Even if it hits the upper end +0.75, that would be only the 17th highest of 74 August NAOs since 1950. The record high is the +1.97 of 2018.

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

 I looked at August NAOs >+1 when JAS RONI wasn’t at a moderate or stronger Nino level:

1) 1955 (Niña) +1.07: Aug very active with 3H incl MH Connie; Sep also very active with 5H incl 3MH

2) 1967 +1.44: Aug very quiet but Sept active with 3H including MH Beulah

3) 1971 +1.55: Aug moderate activity; Sep very active including 4H, with one MH

4) 1976 +1.92: Aug very active with 4H including MH Belle; Sep active with 3H including 1 MH

5) 1983 +1.76: Aug active with 2H including MH Alicia; Sep pretty quiet

6) 1984 +1.15: Aug quiet; Sep active with 2H including MH Diana

7) 1991 +1.23: Aug only 1 NS but it was MH Bob; Sep 3 NS including MH Claudette

8) 1996 +1.02: Aug active with 3H including MH Edouard; Sep very active with 4 MH

9) 2018 +1.97: Aug quiet; Sep active with 3H including MH Florence

10) 2022 (Niña) +1.47: Aug very quiet (no NS); Sep very active with 4H including 2 MH

——————

So for these 10 seasons with strong Aug +NAO:

-Aug: 4 were quiet, 2 had moderate activity, and 4 were active. So, Aug was balanced as compared to climo.

-Sep: only one was quiet (1983), one had moderate activity (1991), and 8 were active.

-In summary regarding the 10 seasons with a strong Aug +NAO: none were shut down in both Aug and Sep, Aug was balanced between quiet and active, and Sep was mainly active. Thus, I see no discernible correlation between a +NAO in August and reduced hurricane activity.

 

Are -NAOs more common in Aug during La Niña? Here’s the Aug NAO when JAS RONI was -0.50 or colder:

1954: -1.90

1955: +1.07

1964: -1.77

1970: +0.10

1973: -0.06

1975: -0.26

1988: +0.04

1995: -0.69

1998: -0.02

1999: +0.39

2007: -0.14

2010: -1.22

2016: -1.65

2020: +0.12

2021: -0.28

2022: +1.47

 

So, tally for RONI based Niña JAS since 1950: 7 -NAO, 6 neutral, 3 +NAO;

AVG NAO  -0.3

 

For RONI based El Niño JAS:

1951: -0.22

1953: -0.71

1957: -0.55

1963: -0.64

1965: +0.45

1968: -0.66

1972: +1.32

1976: +1.92

1977: -0.28

1982: +0.26

1986: -1.09

1987: -0.83

1991: +1.23

1994: +0.38

1997: +0.83

2002: +0.38

2004: -0.48

2015: -0.76

2023: -1.16

So, tally for RONI based Niño JAS since 1950: 10 -NAO, 1 neutral NAO, 8 +NAO

AVG NAO 0.0

[bluewave]

12 hours ago, raindancewx said:

MJO phase five won't do what it has done in recent winters if the WPO is in the opposite phase.

We haven’t had much success with -WPOs during La Ninas since 16-17 when the MJO has been phase 4-7. The only good -WPOs were during MJO phase 8 like in January 22. December 23 featured a strong -WPO but the MJO 4-6 helped pump the SE Ridge and we went snowless for the first time with one of the strongest December -AO patterns on record. We had the -WPO in February 2018 and the first winter 80° around NYC occurred as the MJO went through phases 4-7. The reason the February 2017 -WPO pattern featured a blizzard was also MJO phase 8. But the month was overall very warm due to the amplified MJO 4-7 prior to 8. Plus the more +PDO probably helped us out. 
 

December 22 MJO 4-6 

Jan 22 MJO 8

Feb 2018 MJO 4-7

Feb 2017 MJO 8 after 4-7

 

 

[snowman19]

If you look at when the upper tropospheric temps really started to rise, it was right when the solar flux/geomag and UV started spiking, not a coincidence
 

[40/70 Benchmark]

2 minutes ago, snowman19 said:

If you look at when the upper tropospheric temps really started to rise, it was right when the solar flux/geomag and UV started spiking, not a coincidence
 

I definitely think the high solar has something to do with it.

[snowman19]

I definitely think the high solar has something to do with it.

For sure and it’s showing no sign of letting up. I would not be surprised to see this season finish with an ACE of 110-140

[Typhoon Tip]

1 hour ago, 40/70 Benchmark said:

I definitely think the high solar has something to do with it.

i don't think so - not based upon that data presentation, anyway

on the right side, there's clearly a multi-decadal trend line with a significant positive slope, while on the left hand side ... the scale of that color palate is decimals.    d(t) between 2023 and 2024 results a decimal value that fits along that trend line,  a trend that was established/predates the this recent 6 months if intense solar onset.

[snowman19]

6 minutes ago, Typhoon Tip said:

i don't think so - not based upon that data presentation, anyway

on the right side, there's clearly a multi-decadal trend line with a significant positive slope, while on the left hand side ... the scale of that color palate is decimals.    d(t) between 2023 and 2024 results a decimal value that fits along that trend line,  a trend that was established/predates the this recent 6 months if intense solar onset.

While AGW might definitely be playing a role, if you look back on the 01-02 high solar flux of cycle 23, we saw the same spike in upper tropospheric temps/warming over the low and mid latitudes from the increased UV

[40/70 Benchmark]

7 minutes ago, Typhoon Tip said:

i don't think so - not based upon that data presentation, anyway

on the right side, there's clearly a multi-decadal trend line with a significant positive slope, while on the left hand side ... the scale of that color palate is decimals.    d(t) between 2023 and 2024 results a decimal value that fits along that trend line,  a trend that was established/predates the this recent 6 months if intense solar onset.

Yea, I do not agree that solar isn't a player.

While your analysis of the HC is likely a primary driver this season, even a curosry glance at the data implies a definitive negative correlation between the solar cycle and ACE output.

[bluewave]

On 9/2/2024 at 3:39 PM, so_whats_happening said:

I forget where exactly I read about the potential with a warming world to produce a greening Sahara. Maybe it was the exxon 1982 study that got circulated. 

One of the possibilities is that the record Mediterranean and North Atlantic SSTs can shift the ITCZ further north than usual.

 

[Typhoon Tip]

1 hour ago, snowman19 said:

While AGW might definitely be playing a role, if you look back on the 01-02 high solar flux of cycle 23, we saw the same spike in upper tropospheric temps/warming over the low and mid latitudes from the increased UV

yeah i could nod to this approach

we exist in ( and because of ..) the kind of complexity that is not just linear, but is interactions among products as well.  these latter interactions in turn cause emergence that are difficult ( to put it lightly ) to predetermine, because when attempting to do so, they may not even exist if the linear products are not precise predicted.

with all that calamity ... there's no way, zero possibility, that a systemic behavior is a result of a single input.  

it comes down to amounts of contribution - with a dose of spatial relativity.  

[Typhoon Tip]

1 hour ago, bluewave said:

One of the possibilities is that the record Mediterranean and North Atlantic SSTs can shift the ITCZ further north than usual.

 

you know i have a completely ot thought on that.   the warming med has been prevalent.   i've been wondering if at some point the ohc being an abutter to the aridity of the n africa might get interesting. 

... at what point does (or could) rising saharan heat start drafting in very high latency/wv content - similar to other monsoon circulation modes around the world.  

like i said, ot.  heh

[Typhoon Tip]

oh, duh - the embedded links bluewave provided there seems to suggest that. 

so yeah

[GaWx]

On 9/2/2024 at 10:01 AM, snowman19 said:

@Stormchaserchuck1 Have you seen the new QBO update for August yet? I just read on twitter that it’s up to almost +20. I take what I read there from people who aren’t mets with a grain of salt unless I can verify it as fact myself. If that’s actually true, it’s a real bad sign 

It’s good that you took that Twitter source saying nearly +20 with a grain as it not surprisingly ended up way off. The record high back to 1948 is only +15.62. August came in modestly higher than July’s +6.91. It was +8.61. There’s almost no way it has peaked as it hasn’t peaked below +9 since way back in 1973, which covers ~23 cycles. It has peaked within 5-13 months after the prior low point every time on this chart with an avg of ~8-9 months. So, my educated guess is that the peak will come during fall or winter (likely no earlier than Oct).

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

[GaWx]

The JJA ONI-RONI came in at -0.49. The last 6: -0.63, -0.62, -0.64, -0.61, -0.54, and -0.49.

[snowman19]

11 minutes ago, GaWx said:

 The Twitter source saying nearly +20 not surprisingly ended up way off. The record high back to 1948 is only +15.62. August came in modestly higher than July’s +6.91. It was +8.61. There’s almost no way it has peaked as it hasn’t peaked below +9 since way back in 1973, which covers ~23 cycles. It has peaked within 5-13 months after the prior low point every time on this chart with an avg of ~8-9 months. So, my educated guess is that the peak will come during fall or winter (likely no earlier than Oct).

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

They had to be talking about the anomalies, which you and I already suspected. And I agree, we are nowhere near the peak of this +QBO since it just turned positive in June. The peak very likely doesn’t happen until sometime this winter 

[40/70 Benchmark]

2 hours ago, snowman19 said:

They had to be talking about the anomalies, which you and I already suspected. And I agree, we are nowhere near the peak of this +QBO since it just turned positive in June. The peak very likely doesn’t happen until sometime this winter 

2020 and 2022 are good analogs in that respect...November to January for the peak with my money being on January.

[40/70 Benchmark]

2 hours ago, GaWx said:

The JJA ONI-RONI came in at -0.49. The last 6: -0.63, -0.62, -0.64, -0.61, -0.54, and -0.49.

 I have it a bit lower than that.
JJA 2024  -0.44

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

[40/70 Benchmark]

I think this bodes well for salvaging some sembalance of winter. Keep in mind the precise verbiage there....not expecting 1995 or 2013.

  JJA 2022  -0.82 

[GaWx]

6 minutes ago, 40/70 Benchmark said:

 I have it a bit lower than that.
JJA 2024  -0.44

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

Let me restate as I wrote it wrong. I said JJA ONI-RONI was -0.49. I meant to say RONI-ONI was -0.49. RONI was -0.44 and ONI was +0.05. -0.44 - 0.05 = -0.49.

[40/70 Benchmark]

Just now, GaWx said:

Let me restate as I wrote it wrong. I said JJA ONI-RONI was -0.49. I meant to say RONI-ONI was -0.49. RONI was -0.44 and ONI was +0.05. -0.44 - 0.05 = -0.49.

Jesus, that is confusing. I have never seen anyone make ONI and RONI into an equation.

[40/70 Benchmark]

Interesting....there has only been one official La Nina since 1950 that has registered a JJA ONI this high, which is 2017 also at 0.1 and went onto peak at -1.0.

[GaWx]

1 minute ago, 40/70 Benchmark said:

Jesus, that is confusing. I have never seen anyone make ONI and RONI into an equation.

The point I’m making in showing the progression of the last 6 is to see what the trend of the difference is going toward winter. The difference is important because the models only project ONI. I take those modeled ONIs and adjust them downward based on what I expect RONI-ONI to be. The last 6 have been -0.63, -0.62, -0.64, -0.61, -0.54, and -0.49. It looks like they’re finally starting to trend less negative. Based on that, I feel the difference could be near -0.40 by, say, SON.

[40/70 Benchmark]

Just now, GaWx said:

The point I’m making in showing the progression of the last 6 is to see what the trend of the difference is going toward winter. The difference is important because the models only project ONI. I take those modeled ONIs and adjust them downward based on what I expect RONI-ONI to be. The last 6 have been -0.63, -0.62, -0.64, -0.61, -0.54, and -0.49. It looks like they’re finally starting to trend less negative. Based on that, I feel the difference could be near -0.40 by, say, SON.

Yea, the RONI is going be be probably near the lower end of moderate......I began the summer thinking upper moderate, so that is good.

[bluewave]

3 hours ago, Typhoon Tip said:

you know i have a completely ot thought on that.   the warming med has been prevalent.   i've been wondering if at some point the ohc being an abutter to the aridity of the n africa might get interesting. 

... at what point does (or could) rising saharan heat start drafting in very high latency/wv content - similar to other monsoon circulation modes around the world.  

like i said, ot.  heh

Some of the model projections have wetter Sahara along the south and the drier edge encroaching north into Southern Europe. 

https://www.realclimate.org/index.php/archives/2022/02/future-rainfall-over-sahel-and-sahara/

[FPizz]

5 hours ago, bluewave said:

One of the possibilities is that the record Mediterranean and North Atlantic SSTs can shift the ITCZ further north than usual.

 

Interesting from the one link there they say the Earth orbit made it so that the Sahara region became a desert 6-11 thousand years ago and before that is was lush and with lakes, etc.  Is there any evidence of the earth's orbit possibly going back to resembling what it was back then?

[GaWx]

7 hours ago, 40/70 Benchmark said:

I definitely think the high solar has something to do with it.

 But Phil has yet to say that the high solar is even a possible factor in the upper atmospheric warming. I had hoped he would in yesterday’s update. Not even a mention of solar. To their credit the two Joes at WxBell have been. I’m open to that possibility, especially about the idea of a theoretical lowered ceiling on ACE during very high solar seasons based on my own analysis, but would also like to see peer reviewed studies to either back it up or else refute it. I don’t want to depend on WxBell just saying it. I’m open minded. I had never heard of this possible connection til last week thanks to Joe D.

[bluewave]

22 minutes ago, FPizz said:

Interesting from the one link there they say the Earth orbit made it so that the Sahara region became a desert 6-11 thousand years ago and before that is was lush and with lakes, etc.  Is there any evidence of the earth's orbit possibly going back to resembling what it was back then?

Those greenings were the result of the more gradual temperature change associated with the orbital precession. They are working on newer modeling to handle the faster warming climate of today. So the pattern may vary from what slower changes in the orbit caused.
 

https://theconversation.com/the-sahara-desert-used-to-be-a-green-savannah-new-research-explains-why-216555#:~:text=These images depict a period,%2C Niger%2C Chad and Mali.

[snowman19]

17 minutes ago, GaWx said:

 But Phil has yet to say that the high solar is even a possible factor in the upper atmospheric warming. I had hoped he would in yesterday’s update. Not even a mention of solar. To their credit the two Joes at WxBell have been. I’m open to that possibility, especially about the idea of a theoretical lowered ceiling on ACE during very high solar seasons based on my own analysis, but would also like to see peer reviewed studies to either back it up or else refute it. I don’t want to depend on WxBell just saying it. I’m open minded. I had never heard of this possible connection til last week thanks to Joe D.

Joe D used it to explain what happened with the 01-02 winter. He attributed the increased UV from the high solar flux/max heating the upper troposphere in the low and mid latitudes leading to the SPV shrinking and moving directly over the North Pole and causing the raging zonal PAC jet and very strong westerly flow that winter 

Link: https://www.weatherbell.com/newsletter-10-11-2011-f

[FPizz]

31 minutes ago, bluewave said:

Those greenings were the result of the more gradual temperature change associated with the orbital precession. They are working on newer modeling to handle the faster warming climate of today. So the pattern may vary from what slower changes in the orbit caused.
 

https://theconversation.com/the-sahara-desert-used-to-be-a-green-savannah-new-research-explains-why-216555#:~:text=These images depict a period,%2C Niger%2C Chad and Mali.

Thank you!  I'll read this later.  

[GaWx]

50 minutes ago, snowman19 said:

Joe D used it to explain what happened with the 01-02 winter. He attributed the increased UV from the high solar flux/max heating the upper troposphere in the low and mid latitudes leading to the SPV shrinking and moving directly over the North Pole and causing the raging zonal PAC jet and very strong westerly flow that winter 

Link: https://www.weatherbell.com/newsletter-10-11-2011-f

 Thank you. From your link per Joe D.:

 “The only year since 1998 since I have been doing this which has significantly departed for the seasons was 2001/02 winter when a strong second solar max in terms of solar flux and UV warmed low and mioddle latitude atmospheres and shrunk the polar vortex.

I presented this at NWS regional winter workshops in the fall of 2002 and was invited the present that to CPC in Maryland. High ultraviolet produces warming through ozone chemistry, a finding that was speculated by Labitzke and van Loon (1997) and  confirmed by Hansen's super modeler Drew Shindell (1999) who included ozone chemistry and flux/UV in a special climate model and got improved verficiation retrospectively..They all found a tendency for the warmth to work its way down from the high atmosphere where to the middle troposphere where it affected the jet stream and flow patterns.

The peak in flux/UV in 2001/02 winter was very clear (from September 2001 to March 2002.

 

The resultant warming in the low and middle latiudes was likewise very clear. This is the 500mb height in February. This looks more like the southern hemispehre with a tight polar vortec in blue - trapping real cold air in the polarregions and a warm ring in low and middle latitudes.”

 

My concern is that he is showing only one period, the 2001-2 winter. For statistical credibility reasons, I’d like to see other years/analogs.