2025-2026 ENSO

[LakePaste25]

2 hours ago, EastonSN+ said:

Thanks Don.

I feel that the urban heat island affect has gotten out of hand and unfortunately, central park's temperatures are no longer relevant as a representation of the northeast tri state corridor. Seeing 37 while all other areas were 34 is insane.

Would white plains or newark be a better benchmark moving forward?

I mean, literally one mile away from central park was far colder and received more snow. North south east and west. If we keep using Central Park it will just keep getting worse and will misrepresent the entire area moving forward.

Perhaps we can still use Central Park, but adjust the temperature down. However, this may be a worse idea

It is also one of the coolest stations during summer heatwaves due to the overgrown tree canopy, so this cuts both ways. 

[donsutherland1]

The EPS ensembles' 10-14-day outlook highlights how I think the cold will likely hang on longest in the Northeast/parts of eastern Canada consistent with the forecast teleconnections.

[michsnowfreak]

Snow is beginning to melt here. Been a 3 week stretch of deep winter and while Im not looking forward to the change, Im thinking Jan-Mar will be a wild ride, as most "textbook" Ninas are. This means multiple chances for big snowstorms, arctic blasts, and torches. Im not great at indicies, but Im great at pattern recognition. With all the talk of this being a "textbook" Nina, this is what I see the next 3 months. Wouldnt surprise me if the past 3 weeks is the most sustained any pattern gets all winter. 

[BlizzardWx]

11 hours ago, Stormchaserchuck1 said:

I don't really get this "negative ENSO turned -PNA to +PNA" since 1980 thing. 

1. Why does it only start in the 1980s? Data was not unreliable before then, so it's not like you're starting from a blank point. I think a lack of examples increases the odds of random. If it didn't work before 1980, that's telling, not an ignored difference.

2. That's not what Negative ENSO does. Negative ENSO does not support a +PNA in January. The Hadley cell is extended in the N. Pacific in La Nina more often than not, and that supports -PNA. 

Since we are having such a strong -PNA December, here is a fun roll forward. This is what 500mb January looks like after -PNA Dec.. this is a total composite of 73 years, both - and + signs considered, going back to 1948:

That's an Aleutian ridge in the mean for January. But the ridge is a little further NE, which makes January a cold month for a lot of the US. 

The reason why it will sometimes switch is the MJO runs if 45-day cycles and Kelvin and Rossby waves sometimes run in 45-60 day cycles. We don't have a strong phase of those things now -- it will be interesting to see if we do go more +PNA after the 1st week of January. I think you are discovering a high mathematical random skew. 

This would be a pretty major reversal from the current pattern. Definitely would get a more active storm track so theoretically higher snow chances for many. 

[GaWx]

These images show that the GEFS was too slow in showing the transition from the very strong -PNA of Dec 2021 to the strong +PNA of Jan of 2022:

 12/15/21 GEFS PNA forecast was ok

 

But the 12/26/21 GEFS PNA forecast, which goes through 1/9/22, had all members 0 to -2 for then. The actual 1/9/22 ended up being +0.2. So, it was too slow in predicting the turn to a +PNA:

 

12/31/21 GEFS PNA forecast out to 1/14/22: finally turned to +PNA but not positive enough as 1/14 was actually +0.7 vs this forecast for ~+0.4:

 

1/5/22 GEFS PNA forecast out to 1/19/22: not positive enough as 1/19 was actually +1.0 vs this forecast for only ~+0.1:

 

This shows the actuals for the entire Dec-Jan 2021-2:

[GaWx]

 Check out the widespread much lower H5 for nearly the entire E US on the 12Z GEFS vs the 6Z GEFS as of 0Z 12/30 helped mainly by the apparently even stronger -NAO: