2025-2026 ENSO

[stadiumwave]

4 hours ago, PhiEaglesfan712 said:

Previous years with similar ENSO/IOD/PDO patterns. They tend to have cool Decembers, but torch in January and February.

Actually not the -QBO years with anykind of early strat warming. JAN is the coldest in that analog package. Will not be this year but just saying. 

[BlizzardWx]

1 minute ago, GaWx said:

 The 12/13/25 WPO of -348 is the most negative WPO on any day in December since 12/25/1996!

 The only Decembers since 1948 with at least one day lower than -348 are:

1996, 1989, 1983, 1977, 1966, 1955

I've been trying to think about what is "going wrong" with such a prolific -WPO to be talking about record warmth down my way. Do you know if a -WPO is typically good for the southern Plains? Is it perhaps atypical to have a -WPO paired with a -PNA or is that typical? I know when I look at the current pattern it seems reasonable to have a west coast trough downstream of that high but maybe sometimes ridging extends further southeast? 

Mostly just trying to build my understanding for this index. 

[GaWx]

 Well, as of Dec 13th, the MJO still hasn’t returned to phase 8! It was in 8 only Dec 3rd-7th. Dec 8th-13th have all been in very weak (essentially neutral) phases 5-7. I still think it has a good chance to get back into 8 very soon, but we’ll see:

[PhiEaglesfan712]

3 hours ago, bncho said:

Genuinely curious--could you provide some examples?

The most obvious ones are the most recent: 2016-17 and 2022-23.

2 hours ago, MJO812 said:

Nothing

I have a hard time seeing a torch in January and February with a neutral enso going into el nino.

In case you forgot, here's what happened the last time a dissipating la nina led into an el nino:

[GaWx]

1 hour ago, BlizzardWx said:

I've been trying to think about what is "going wrong" with such a prolific -WPO to be talking about record warmth down my way. Do you know if a -WPO is typically good for the southern Plains? Is it perhaps atypical to have a -WPO paired with a -PNA or is that typical? I know when I look at the current pattern it seems reasonable to have a west coast trough downstream of that high but maybe sometimes ridging extends further southeast? 

Mostly just trying to build my understanding for this index. 

 I’ll check now for December. These 9 were solidly -WPO Decembers dominating throughout the entire month:

2013, 2010, 2009, 2005, 1995, 1989, 1980, 1961, and 1956. Of these:

 

1) Cold in the S Plains?

2013, 2009, 2005, 1989, 1961

 

2) Near normal S Plains?

2010, 1995

 

3) Mild S Plains?

1980, 1956

 

 So, strong -WPO Decembers leaned somewhat to the cold side in the S Plains, but only 5 of 9 averaged cold. It looks like this year may end up averaging near normal based on a cold 1st half and mild 2nd half. But we’ll see.

 

PNA for these 9 Decembers:

2013: moderate -PNA

2010: strong -PNA

2009: weak +PNA

2005: strong +PNA

1995: moderate +PNA

1989: moderate +PNA

1980: weak -PNA

1961: strong -PNA

1956: weak -PNA

 

 So, PNA for these solidly -WPO Decembers is very mixed.

[snowman19]

7 hours ago, GaWx said:

 The 12/13/25 WPO of -3.48 is the most negative WPO on any day in December since 12/25/1996!

 The only Decembers since 1948 with at least one day lower than -3.48 are:

1996, 1989, 1983, 1977, 1966, 1955

The 1989-90 winter saw what was probably the biggest complete pattern flip in the last 50+ years. We went from a record cold arctic ice box from November through the end of December, then there was a big cutter on New Year’s Eve and a light switch flip to a full on torch for all of January and February 

[EasternLI]

Two clusters on eps cluster analysis in the long range last night. -NAO of unknown impact the general idea. There is a road in some analogs where we start January with a -NAO and as we lose that, the PNA goes positive. Could we take that road this year?

[40/70 Benchmark]

8 hours ago, GaWx said:

 The 12/13/25 WPO of -3.48 is the most negative WPO on any day in December since 12/25/1996!

 The only Decembers since 1948 with at least one day lower than -3.48 are:

1996, 1989, 1983, 1977, 1966, 1955

All 6 of those seasons finished with a mean DM -WPO, so this season should, too....though we could have a month or two average +WPO, as was the case in 1990. Looks like I am going to be off on the WPO again...it's so tough to forecast. At least I didn't go strongly positive....