Stormchaserchuck1

It comes down to what they are, and what they do. They interact with the Hadley Cell, and North Pacific High. One creates low pressure, the other high pressure.

We only have global satellite maps from 1948 on, but the US climate division has data way before then, from the 1800s. You can kind of piece together the NAO if you know what it is... does someone have a reliable list of ENSO events 1800s-1948?

In the map that I posted earlier this page of anti-Strong El Nino's, you can see there is a -NAO signal... so maybe correct that by moving the cold from the Northeast and Great Lakes to the Upper Midwest... I think going forward it could happen, and it not happening or happening the same is maybe like a +5-10% probability.

I just don't think it's that high of a correlation.. people swear by datasets, but I can easily see the NAO deviating in future years.. maybe if we go back to the early 1900s there are a lot more wild card NAO happenings, as El Nino's and La Nina's both fluctuate from very warm to very cold in those composites.

ENSO does slightly effect the Stratosphere. That's probably your best hook for this.

I understand it makes the whole system nice and easy, but there's little reason why ENSO would effect the NAO that much. NAO is not driven completely by what occurs over the Pacific. Not going to argue this more when it's saying that the data we have is not statistically significant, but the NAO is not likely to be consistently in the same states going forward as the 3/3 times weaker ENSO or whatever in the past..

The effect of ENSO is mostly on the Pacific.. the dataset is too limited to have statistical significance yet, wrt something more far away, like the NAO.

Given 100 more samples, I don't think you will see that as strongly. Maybe a 0.05 correlation/1 (5%).

I don't think NAO associated with ENSO is as highly correlated as you think.. it might just be a coincidence of sample years so far (6/8 or something). They do connect with Stratosphere though.. +QBO and La Nina favors +AO, while -QBO and El Nino favors -AO.

Yeah, here's what Strong La Nina's would look like if they were completely east-based like the Strongest El Nino's:

But they are relative states of the same weather on the equator.. if one is less than, than the greater than should have opposite effects. The reason why both appear bad is because of lack of data, and because historically stronger La Nina's have usually been west-based, which is focused near 180W/0. If the La Nina was east-based like these massive Strong El Nino's have been, then you might see a very cold pattern in the northern US and Canada.

Yes.. it's the same for Strong El Nino's vs Weak El Nino's. It's not a given that the NAO will be negative in Weak El Nino. To assess whether strong or weak is better or worse, you have to surmise which the better pattern is, El Nino or La Nina.. they should actually be opposites of each other as far as anomalies go. If Strong El Nino is so bad, then Strong La Nina is so good... the difference is we've never really seen a strong east-based La Nina like some of the stronger east-based El Nino's. Orientation on the equator is a difference maker. But a -3c La Nina in Nino 1+2... should be cold near the Great Lakes..

Interesting.. I don't think it's impossible to see 20 storms.. the 3 year trend is an increasing one. Last October we had a period of activity that rivals some of the most active periods on record.

But that's because of lack of data! Lol, people will never hear me on this. Weak la Nina's are not an entity of their own, separate from Strong La Nina's.

I think they are kind of aggressive.. the east coast Carolina's-north has not been hit with a big storm for a while, besides what has made landfall in the Gulf of Mexico, and they have 1-3 impacting systems there, and 0-2 in the Northeast. It just goes against what we have seen since the year 2000, where there is a like a 20% probability rate or less of the East Coast getting hit from an Atlantic Hurricane year-to-year. I think Sandy was the last major one to impact the East Coast.. I think as long as we don't go into an El Nino, the projected numbers will be pretty high.. SSTs are warming in the Gulf of Mexico and Caribbean nicely, but 20 Named Storms might be a little high.. you need a lot of things to go right for that to verify.

1948-2022, we had 12 named storms or less for all Moderate+ El Nino's. Then in 2023, we had 20 Named storms during a Strong El Nino! The 2023 Atlantic hurricane season was the fourth-most active Atlantic hurricane season on record with 20 named storms forming, tied with 1933. It was a Strong El Nino. That indicated a general increase in Atlantic storm probability.

Latest SSTA.. cold water off of Africa, warm Gulf of Mexico. Nino 1+2 warm, Nino 3/4 cold.

Yeah, east vs west-based ENSO is different. East has more of a North Pacific high correlation, and west is more connected to PNA.

Not to be confused with it correlating with NAO.. big difference. An example: There are 8 Weak La Nina's and 6 have -NAO. You would think that they are connected, but that's actually too low of a sample size. I just use the NAO in this example to provide a divider so that it can be more easily understood what I mean. It's a tough one to overcome believe it or not mentally, but given 100 historical examples, Weak ENSO will look "weak" in the composite, and Strong ENSO will look strong.. however, what they are correlated to (SE ridge or whatever) will be in the same spot in both sample sets, given enough examples.

Too bad it's not 1 month sooner, or this would have been snow Rain, 38F Not bad for a monster 500mb ridge over us.

I mean in the maps.. with 100 years more data, Weak ENSO events will look "weak" in the composites. and strong ENSO events will give a "strong" signal. The problem now with 7-9 years in the data is that other things like the NAO have more impact with weaker ENSO. (It doesn't have to do with the frequency of Weak vs Moderate vs Strong events occurring, I'm talking about their correlated effects - stronger has stronger effects, weaker has weaker effects).

^It's one of the highest correlations I've ever done on the NOAA Physical science maps. If you have the time, I highly recommend that people go back to 1948 (the start of their dataset) and look at all cold season 10mb events vs the 500mb pattern. What I found is spectacular! The Stratosphere warming (+10mb geopotential height) signal translates to -NAO at different times of the year: October: +60 days November: +45 days December: +30 days January: +25 days February: +20 days March: +15 days April: +10-15 days The mean for daily composites in the allotted times was as high as a +120dm -NAO mean signal! For cold Stratosphere times (-10mb geopotential height), it's not the same as a warming! The effect on the surface and 500mb is immediate! October: + 0 days November: + 0 days December + 0 days January: + 0 days February: + 0 days March-April: + 0 days We are still mastering science, and I expect improvements with further research, but the basic reading is already a high correlated factor, generally. This particular one is not hitting it besides a 3-4 day period though. Not really surprising because we had so many strong/near record breaking +NAO periods in 2024.

Weak vs Moderate vs Strong ENSO is just different amplitude of the same thing. I think the differences are just from not having enough climate data and weaker events having more weight from other things. With 50-100 more years of climate data, the differences will be sorted out and you'll only see a "weak" vs "strong" signal in the data.

Stratosphere warming is still going strong.. one of the strongest ones in history, actually, because it's having these +1800dm anomalies cover 3-4 weeks. I think the highest I ever saw 10mb get historically on a daily was +2900dm. Latest daily map 3-10 is about when it started.. last 22 days: It will probably last for another week.

Northern Hemisphere version of SOI. Pressure difference between the North Pacific High and Tahiti I think.