Mid to long range discussion- 2025

[wncsnow]

Looks like the cold is going to center in the rockies/northwest first and we have a big ridge until the end of the month

[Daniel Boone]

3 hours ago, wncsnow said:

Looks like the cold is going to center in the rockies/northwest first and we have a big ridge until the end of the month

Yep. MJO taking control of the Bus. Blocking may mitigate the Heat in the East by squashing the SER. Hopefully that western trough doesn't dig too deep and help the SER hook up with the -NAO. Models are not showing that but after seeing that happen the last several Years it makes it a possibility.

[wncsnow]

51 minutes ago, Daniel Boone said:

Yep. MJO taking control of the Bus. Blocking may mitigate the Heat in the East by squashing the SER. Hopefully that western trough doesn't dig too deep and help the SER hook up with the -NAO. Models are not showing that but after seeing that happen the last several Years it makes it a possibility.

Exactly. That's my main concern and it's incredibly hard to get rid of 

[wncsnow]

Long range continues to look generally warm on ops and ensembles. When does it flip?

[calculus1]

Doesn’t need to flip until December, at the earliest. No sense wasting all the good teleconnections in November, when most of us can’t get snow anyway, despite the upper air patterns.


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[PackGrad05]

2 minutes ago, calculus1 said:

Doesn’t need to flip until December, at the earliest. No sense wasting all the good teleconnections in November, when most of us can’t get snow anyway, despite the upper air patterns.


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Agreed.  I'll take it in late December/all of January.

[Met1985]

1 hour ago, wncsnow said:

Long range continues to look generally warm on ops and ensembles. When does it flip?

Honestly a transition the first of December would be best climatologically speaking. 

[SUNYGRAD]

[WinstonSalemArlington]

Eww

[wncsnow]

I agree that a perfect pattern now would likely mean no snow outside the mountains but patterns repeat themselves and the one the next few weeks looks very Nina ish

[Daniel Boone]

Interesting development in the North Atlantic. SST'S becoming favorable for a -NAO this Winter. 

https://x.com/Aigle_e/status/1989420648234668098?s=20

[NorthHillsWx]

Worried about SER this winter. I’ve seen this tune before it gets going and PNA continues to screw us until a one week post frontal cold snap in January especially in a La Niña year. This setup is tough to burn in the SE especially when it’s already rearing its head. Could flip, but color me concerned with PNA trending negative. At least it’s mid November not mid December heading into a screwball pattern but winters where the SER gets going and Pacific trends to hell tend to have repeat performances through the season and being a Nina year It doesn’t feel great seeing this pattern show up 

[eyewall]

3 hours ago, NorthHillsWx said:

Worried about SER this winter. I’ve seen this tune before it gets going and PNA continues to screw us until a one week post frontal cold snap in January especially in a La Niña year. This setup is tough to burn in the SE especially when it’s already rearing its head. Could flip, but color me concerned with PNA trending negative. At least it’s mid November not mid December heading into a screwball pattern but winters where the SER gets going and Pacific trends to hell tend to have repeat performances through the season and being a Nina year It doesn’t feel great seeing this pattern show up 

I was hoping this would be the year for a 6 inch plus event but I am not so optimistic now.

[NorthHillsWx]

58 minutes ago, eyewall said:

I was hoping this would be the year for a 6 inch plus event but I am not so optimistic now.

At least we’re not burning prime climo but I am very concerned given it being Nina and pacific heading to crap. All this blocking and +PNA we’ve had has still managed to produce a “heatwave” and northern storm track so losing blocking and pacific turning bad does not bode well 

[GaWx]

4 hours ago, NorthHillsWx said:

Worried about SER this winter. I’ve seen this tune before it gets going and PNA continues to screw us until a one week post frontal cold snap in January especially in a La Niña year. This setup is tough to burn in the SE especially when it’s already rearing its head. Could flip, but color me concerned with PNA trending negative. At least it’s mid November not mid December heading into a screwball pattern but winters where the SER gets going and Pacific trends to hell tend to have repeat performances through the season and being a Nina year It doesn’t feel great seeing this pattern show up 

 I just looked up -ENSO winters with a -PNA in Dec to see how often it went to a +PNA in Jan. In what winters did this occur?

-1954-5: -0.52 to +0.40

-1962-3: -0.08 to +0.58

-1983-4: -0.31 to +0.97

-1984-5: -1.60 to +1.63

-1996-7: -1.23 to +0.63

-1998-9: -0.09 to +0.16

-2008-9: -1.41 to +0.61

-2010-11: -1.78 to +1.29

-2012-3: -1.01 to +0.55

-2013-4: -0.86 to +0.97

-2016-7: -0.35 to +0.28

-2021-2: -2.56 to +1.01

-2022-3: -0.66 to +0.22

 So, although it wasn’t common from 1954-5 through 1971-2, when only 2 of 9 (22%) switched, here’s something that just blew my mind:

-ALL 11 -ENSO -PNA Decs since 1983-4 switched to +PNA Jans (listed above)!

-These 11 averaged +0.76 in January!

-Now, check out the -ENSO Jan PNAs since 1983-4 that had a +PNA in Dec:

1) 1985-6 went from +1.39 to +0.97

2) 1988-9 went from +0.63 to -0.72

3) 1995-6 went from +0.92 to -0.02

4) 1999-00 went from +0.21 to -0.82

5) 2000-01 went from +1.23 to +1.51

6) 2001-2 went from +0.56 to -0.04

7) 2005-6 went from +1.38 to -0.43

8) 2007-8 went from +0.14 to -0.32

9) 2011-2 went from +0.36 to +0.60

10) 2017-8 went from +0.89 to +0.40

11) 2020-1 went from +1.58 to +0.19

12) 2024-5 went from +1.70 to +1.05

 -So, for these 12 -ENSO Decs since 1983-4 with a +PNA, only 50% also had a +PNA in Jan.

-So, since 1983-4, whereas only 50% of the 12 -ENSO Decs with a +PNA also had a Jan +PNA, 100% of the 11 -ENSO Decs with a -PNA in Dec went to a +PNA in Jan! Thus, having a -PNA in Dec during -ENSO since 1983-4 has, if anything, meant a big increase in the chance for a +PNA in Jan whether random or not! I didn’t know this til just now.

Link to monthly PNAs back to 1950:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

[NorthHillsWx]

2 hours ago, GaWx said:

 I just looked up -ENSO winters with a -PNA in Dec to see how often it went to a +PNA in Jan. In what winters did this occur?

-1954-5: -0.52 to +0.40

-1962-3: -0.08 to +0.58

-1983-4: -0.31 to +0.97

-1984-5: -1.60 to +1.63

-1996-7: -1.23 to +0.63

-1998-9: -0.09 to +0.16

-2008-9: -1.41 to +0.61

-2010-11: -1.78 to +1.29

-2012-3: -1.01 to +0.55

-2013-4: -0.86 to +0.97

-2016-7: -0.35 to +0.28

-2021-2: -2.56 to +1.01

-2022-3: -0.66 to +0.22

 So, although it wasn’t common from 1954-5 through 1971-2, when only 2 of 9 (22%) switched, here’s something that just blew my mind:

-ALL 11 -ENSO -PNA Decs since 1983-4 switched to +PNA Jans (listed above)!

-These 11 averaged +0.76 in January!

-Now, check out the -ENSO Jan PNAs since 1983-4 that had a +PNA in Dec:

1) 1985-6 went from +1.39 to +0.97

2) 1988-9 went from +0.63 to -0.72

3) 1995-6 went from +0.92 to -0.02

4) 1999-00 went from +0.21 to -0.82

5) 2000-01 went from +1.23 to +1.51

6) 2001-2 went from +0.56 to -0.04

7) 2005-6 went from +1.38 to -0.43

8) 2007-8 went from +0.14 to -0.32

9) 2011-2 went from +0.36 to +0.60

10) 2017-8 went from +0.89 to +0.40

11) 2020-1 went from +1.58 to +0.19

12) 2024-5 went from +1.70 to +1.05

 -So, for these 12 -ENSO Decs since 1983-4 with a +PNA, only 50% also had a +PNA in Jan.

-So, since 1983-4, whereas only 50% of the 12 -ENSO Decs with a +PNA also had a Jan +PNA, 100% of the 11 -ENSO Decs with a -PNA in Dec went to a +PNA in Jan! Thus, having a -PNA in Dec during -ENSO since 1983-4 has, if anything, meant a big increase in the chance for a +PNA in Jan whether random or not! I didn’t know this til just now.

Link to monthly PNAs back to 1950:

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

This is great research as always. Gives credence to the theory, at least we aren’t burning good snowfall climo with a crap pattern. Will hurt the ski resorts and delay onset of winter, but if it was December 16 and the indices were trending the way they are we’d be in trouble 

[BooneWX]

https://x.com/bennollweather/status/1990036396615274867?s=46


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[wncsnow]

1 hour ago, BooneWX said:

https://x.com/bennollweather/status/1990036396615274867?s=46


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That's sobering

[Met1985]

10 minutes ago, wncsnow said:

That's sobering

Nothing we don't know especially the past 5 winters. Hopefully things look up starting this winter.

[wncsnow]

1 minute ago, Met1985 said:

Nothing we don't know especially the past 5 winters. Hopefully things look up starting this winter.

Imagine how bad it would be without the big snow in 2022? 

[Met1985]

13 minutes ago, wncsnow said:

Imagine how bad it would be without the big snow in 2022? 

That's our climate though.  Usually people outside the mountains just need 1 big snow to make their annual snowfall. 

[calculus1]

1 hour ago, Met1985 said:

That's our climate though.  Usually people outside the mountains just need 1 big snow to make their annual snowfall. 

True, but we haven’t gotten that one snowfall in any of the past five years. It’s been a complete famine here east of the mountains, and that graphic shows how stark our situation has been compared to the rest of the country. Let’s change the trend…

[NorthHillsWx]

What I take away from that map is more of an east coast problem than just somewhere in the Carolina’s and it all stems back from the insane lack of coastal storms that have worked. To me, this is where climate shifts have caught up with snowfall. Our biggest snows have always been and will always be from coastal lows. Recently, every coastal system has either missed, or the BL has been too warm for snows. These are always borderline systems where the heaviest snows fall in 31-33 degree temps so a swing of 1-2 degrees will absolutely destroy what otherwise was a perfect track system. You’ve seen this up and down the coast and unfortunately this might be more common in the future. The snows we have gotten including the two all snow events last year were in deep cold air masses with coastal lows either too weak or too far offshore to produce enough QPF for heavier amounts. I know eastern N.C. got lucky and it can still happen, but it just seems like it takes more than it used to to get coastal lows to produce snowfall in the piedmont and up the east coast. I remember the I-85 snow line when that was a thing and the rain snow line wasn’t somewhere in Virginia. We used to have 1-2 of these a year at least where Raleigh would have some kind of mix to rain and places west of here got plastered. Recently it’s been all rain or just a brief roxboro mix to rain. That’s what I see the most out of that map and it gives me a lot of concern for the future as our main form of bigger snowfall seems to be taken away by background warming 

[Met1985]

13 hours ago, calculus1 said:

True, but we haven’t gotten that one snowfall in any of the past five years. It’s been a complete famine here east of the mountains, and that graphic shows how stark our situation has been compared to the rest of the country. Let’s change the trend…

Very true and hopefully we cycle through to better years with more snowfall.