2026-2027 El Nino

[Stormchaserchuck1]

Western ENSO subsurface continues to strengthen, making me think 57-58, 65-66, 86-87, 91-92, and 15-16 could be top analogs.  >+4c on TAO/Triton at 160E, -150m

[snowman19]

17 minutes ago, Stormchaserchuck1 said:

Western ENSO subsurface continues to strengthen, making me think 57-58, 65-66, 86-87, 91-92, and 15-16 could be top analogs.  >+4c on TAO/Triton at 160E, -150m

That’s from the massive DWKW Paul Roundy and Eric Webb talked about over the weekend. It’s going to advect and slosh east through Ekman pumping just like they all do.

 

 

 

 

[Stormchaserchuck1]

Let's see if it makes it all the way to Nino 1+2

[snowman19]

Models still showing a robust +IOD developing over the coming months

[Stormchaserchuck1]

Coming precip patterns are pre-El Nino

Apr-May precip before later-in-the-year Nino 3.4 El Nino's:

6-14 day CPC forecast

[snowman19]

[GaWx]

13 minutes ago, snowman19 said:

 

 Indeed, the CFSv2 gets Nino 3 to just above +3.0 in Nov and Dec for non-relative anomalies:

[Stormchaserchuck1]

I think models are overdoing it -- you want the SOI to be lower, but it never got strong in 2023 so it may still be a lagging indicator, which it has been for the last 3 years. 

[roardog]

What’s the deal with all this extreme warmth in Nino 4 during recent El Niños? When you think of the classic strong/super Nino you always think of Nino 4 not being too warm or maybe even below normal. Nino 4 is up to +1 already according to Cyclonicwx. 

[Stormchaserchuck1]

23 minutes ago, roardog said:

What’s the deal with all this extreme warmth in Nino 4 during recent El Niños? When you think of the classic strong/super Nino you always think of Nino 4 not being too warm or maybe even below normal. Nino 4 is up to +1 already according to Cyclonicwx. 

Bluewave has posted graphs of a linear warming trend in Nino 4, 1950-present. It's much more of a straight line than other ENSO regions. 

[snowman19]

[snowman19]

[PhiEaglesfan712]

[40/70 Benchmark]

16 hours ago, Stormchaserchuck1 said:

Western ENSO subsurface continues to strengthen, making me think 57-58, 65-66, 86-87, 91-92, and 15-16 could be top analogs.  >+4c on TAO/Triton at 160E, -150m

Exactly the type of analogs I was speculating on. 2002 is similar, but obviously weaker. I think the issue will be the NAO...1991-1992 was awful because it was the only strongly positive NAO/weakly -PDO, which we may very well have this year.

[40/70 Benchmark]

[GaWx]

 This illustrates how much warmer the surrounding tropical areas were during 2023-4, which means a RONI significantly cooler than ONI due to the lowered contrast:

 

 Look at the much larger contrast in 1982-3:

[40/70 Benchmark]

[40/70 Benchmark]

[40/70 Benchmark]

1957 is best subsurface map in terms of placement AND intensity of subsurface warm pool. It's also a good polar analog in terms of solar and QBO.

[bluewave]

16 hours ago, roardog said:

What’s the deal with all this extreme warmth in Nino 4 during recent El Niños? When you think of the classic strong/super Nino you always think of Nino 4 not being too warm or maybe even below normal. Nino 4 is up to +1 already according to Cyclonicwx. 

Probably related to the big expansion of the +30C warm pool in the Pacific which is several degrees warmer than we would get back in the old days with the strongest El Niños before the oceans warmed so much.

 

 

[40/70 Benchmark]

12 minutes ago, bluewave said:

Probably related to the big expansion of the +30C warm pool in the Pacific which is several degrees warmer than we would get back in the old days with the strongest El Niños before the oceans warmed so much.

 

 

This is why we are seeing less of an Aleutian low/se trough response.

[bluewave]

18 minutes ago, 40/70 Benchmark said:

This is why we are seeing less of an Aleutian low/se trough response.

Yeah, could be related. Same for the El Nino trough in the East which was much weaker in 2015-2016 and 2023-2024.

I also think the much warmer adjacent off equator and subtropical oceans could be warping the response also. Those subtropical seas were so much warmer this winter that the weak La Niña ridge in the Southwest was so much stronger than the 1995-1996 weak La Niña response.

It’s a bit challenging to give a specific value to just how much each individual marine heatwave is contributing. I have also been noticing discussions already taking place about the new RONI index. I went back and reread the paper on RONI and seems like most of the value was with La Ninas where the off equator warmth was masking the La Niña response.

But when it comes to the strongest El Niños they can appear weaker than the past ONI. But as we saw from 2023-2024, the weaker RONI didn’t correspond to a weaker ridge over Canada and the Northern Tier and any less warmth. Plus the global temperature jump was even more impressive than past even stronger ONI higher end El Niños.

But we could make an argument that the weaker RONI and warmer off equator to subtropical SST warmth could have weakened the Aleutian trough and the trough in the East under the big ridge. This could also warp the rainfall response in some way than we normally get with such strong El niños related to the Southern Stream response.

This is why we should probably still use the traditional ONI for the actual El Niño intensity and incorporate the RONI for the finer details like how the Aleutian Low and other troughs are responding.

[40/70 Benchmark]

10 minutes ago, bluewave said:

Yeah, could be related. Same for the El Nino trough in the East which was much weaker in 2015-2016 and 2023-2024.

I also think the much warmer adjacent off equator and subtropical oceans could be warping the response also. Those subtropical seas were so much warmer this winter that the weak La Niña ridge in the Southwest was so much stronger than the 1995-1996 weak La Niña response.

It’s a bit challenging to give a specific value to just how much each individual marine heatwave is contributing. I have also been noticing discussions already taking place about the new RONI index. I went back and reread the paper on RONI and seems like most of the value was with La Ninas where the off equator warmth was masking the La Niña response.

But when it comes to the strongest El Niños they can appear weaker than the past ONI. But as we saw from 2023-2024, the weaker RONI didn’t correspond to a weaker ridge over Canada and the Northern Tier and any less warmth. Plus the global temperature jump was even more impressive than past even stronger ONI higher end El Niños.

But we could make an argument that the weaker RONI and warmer off equator to subtropical SST warmth could have weakened the Aleutian trough and the trough in the East under the big ridge. This could also warp the rainfall response in some way than we normally get with such strong El niños related to the Southern Stream response.

This is why we should probably still use the traditional ONI for the actual El Niño intensity and incorporate the RONI for the finer details like how the Aleutian Low and other troughs are responding.

Yea......look at the absolute value of each to obtain a general idea of how strong the event is, but more importantly, it's the relationship between the RONI and ONI that is indicative of the type of response that ENSO may induce around the hemisphere. The latter is what we really need to understand because knowing how strong said response will be is pretty useless if we have no idea what the response will be.

I suspect we are going to need the RONI to be at least equivalent or greater than the ONI to avoid yet another muted  Aleutian low/se trough couple response. If we have a very strong El Nino with a lagging ONI, as was the case in 2023, then you get a very strong RIDGING response over se Canada and an Aleutian low/se trough that is still meager.

[40/70 Benchmark]

Just now, GaWx said:

Chris,

 For actual El Niño intensity, why would you want to use ONI instead of RONI? Say, for example vs 1991-2020 means, tropical waters worldwide were averaging +2C and ONI was averaging the same, +2C. Per RONI, this would be right at perfect neutral. To me, that makes more sense in determining El Niño strength. The forcing from Nino 3.4 isn’t there when it’s neighboring waters are about the same. There’s no warm tongue when it is warm all around it 

 

Just now, 40/70 Benchmark said:

Yea......look at the absolute value of each to obtain a general idea of how strong the event is, but more importantly, it's the relationship between the RONI and ONI that is indicative of the type of response that ENSO may induce around the hemisphere. The latter is what we really need to understand because knowing how strong said response will be is pretty useless if we have no idea what the response will be.

I suspect we are going to need the RONI to be at least equivalent or greater than the ONI to avoid yet another muted  Aleutian low/se trough couple response. If we have a very strong El Nino with a lagging ONI, as was the case in 2023, then you get a very strong RIDGING response over se Canada and an Aleutian low/se trough that is still meager.