2025-2026 ENSO

[40/70 Benchmark]

34 minutes ago, donsutherland1 said:

With regard to the EPO, I suspect the current issue is less one about whether it can go positive or negative, but the issue of decreasing variability. In other words, there is greater stickiness for either a positive regime or negative regime during winter and that tendency has increased in recent years. More broadly, this tendency would be consistent with the growing evidence that "stuck patterns" are growing more frequent.

And if one looks more closely, the stuck patterns seem to be starting to break in favor of EPO+ values. Here are ratios of the percentage of postive and negative days in January-February vs. percentage of positive and negative days in December. These are currently modest trends.

I'll go out on a limb and say we won't be stuck in +EPO patterns for the majority of winter 2025-2026.

[donsutherland1]

54 minutes ago, 40/70 Benchmark said:

I'll go out on a limb and say we won't be stuck in +EPO patterns for the majority of winter 2025-2026.

I don't expect that outcome either. 

[40/70 Benchmark]

4 minutes ago, donsutherland1 said:

I don't expect that outcome either. 

WPO I am less confident in.

[snowman19]

1 minute ago, 40/70 Benchmark said:

WPO I am less confident in.

As far as the WPO goes….I have to agree with you there. The WPAC SST pattern over the last couple of months up to now is matching past years that had predominantly +WPO winters. If that doesn’t change in a big way between now and the end of November, a +WPO winter would not surprise me

[40/70 Benchmark]

3 minutes ago, snowman19 said:

As far as the WPO goes….I have to agree with you there. The WPAC SST pattern over the last couple of months up to now is matching past years that had predominantly +WPO winters. If that doesn’t change in a big way between now and the end of November, a +WPO winter would not surprise me

I do not think it will be as extreme, though....yes, the west PAC is still warm, but the warmth has spread east...think of it as kind of like a the RONI effect with respect to ENSO. Remeber the 2023-2024 El Nino and how the west warm pool mitigated and altered the warm ENSO impression around the hemisphere.

I think that warmth further east will act to neutralize things to an extent.