November Mid/Long Range Discussion

[brooklynwx99]

5 minutes ago, WxUSAF said:

No idea where this came from and looks nothing like GEFS or EPS, but it is nice to look at.

GEFS is also showing a WB -NAO... Pacific isn't great, but good to see the blocking showing up

[brooklynwx99]

EPS also making a shift towards much more medium range -NAO blocking

[psuhoffman]

Hell hath frozen over 

https://x.com/webberweather/status/1727402563329548471?s=46&t=JDI46BeqOMUGnLaA2k6MTw

[87storms]

1 hour ago, AtlanticWx said:

per eric webb, here's a plot of the JFM difference between the 10 most negative NAOs during december vs 10 most positive NAOs during december. using statistical t-tests, he found a significance of 98% between the two datasets showing that a december -NAO during a nino can go a long way for the rest of the season. take 2009-10 for example which had a crazy december -NAO, which set us up for the monster winter to come.

most long range models right now have a sustained -NAO going into december, and while the gefs extended has a +NAO, the gefs has been trending towards a much more sustained -NAO (esp 12z which made a huge nod to CMC/Euro weeklies), so going off of this correlation which has actual statistical significance (~98%) unlike other metrics this board has been using, if we get a -NAO that's sustained throughout December, this winter should turn out pretty cold and possibly snowy too.

 

I like this kinda stuff.  The only thing I'm wondering is why the comparison would be done between two extremes instead of the most negative NAO vs a neutral NAO.

[brooklynwx99]

if we get that -NAO, it bodes well for the rest of the winter. El Ninos with -NAO Decembers looked like this for Jan / Feb:

[CAPE]

50 minutes ago, brooklynwx99 said:

EPS also making a shift towards much more medium range -NAO blocking

The GEFS/EPS have been depicting a nice a ridge in the NAO domain over multiple runs for the very end of Nov/first few days of Dec, induced by the deep upper trough that digs south, brings the cold shot and shifts NE over eastern Canada. After the first few days of Dec it morphs into more of a Hudson Bay ridge though, as the TPV shifts north/EPO ridge breaks down. The GEPS seems to be following the same progression in the NA, just taking a few more days. The PAC is a better look at the end of the GEPS run though.

[Eskimo Joe]

2 hours ago, aldie 22 said:

I'm not going to EJ or Ji it but seeing a 384 hour GFS op run with zero precip from start to finish isn't much fun to look at.

You're learning.

1 hour ago, brooklynwx99 said:

GEFS is also showing a WB -NAO... Pacific isn't great, but good to see the blocking showing up

Good Atlantic, but terrible Pacific. We can't win this year.

[CAPE]

There is some improvement on the 12z EPS compared to 0z in Canada/NAO domain (and to a lesser degree the NPac) for the end of the first week of met winter. We shall see which way the pattern goes beyond Dec 3- some of that answer depends on the MJO progression. It could just be a brief reshuffle and a short lived milder period before a mid month reload. Just a few more model cycles..

 

[cbmclean]

Honest question: Would a-NAO really be of interest?  Didn't we learn last December that it is powerless against a bad PAC?

[WxUSAF]

3 minutes ago, cbmclean said:

Honest question: Would a-NAO really be of interest?  Didn't we learn last December that it is powerless against a bad PAC?

You’re not wrong. Most of this discussion is following from one of Webb’s tweets today discussing that -NAO Decembers in Ninos usually suggest persistent -NAO for the whole winter. Even though the EPS plot @CAPE showed above is improved from 0z, it’s not a cold/snow pattern because of that strong -PNA.

[brooklynwx99]

4 minutes ago, WxUSAF said:

You’re not wrong. Most of this discussion is following from one of Webb’s tweets today discussing that -NAO Decembers in Ninos usually suggest persistent -NAO for the whole winter. Even though the EPS plot @CAPE showed above is improved from 0z, it’s not a cold/snow pattern because of that strong -PNA.

yeah, it's not cold enough early (unless the GEPS -EPO is right), but seeing the -NAO and SPV perturbation both showing up over the last few days is highly encouraging

it would be leading us on the 2002/2009 type track rather than the 1972/1982/1991/2015 track

[Ralph Wiggum]

2 hours ago, brooklynwx99 said:

EPS also making a shift towards much more medium range -NAO blocking

Looks exactly where last year left off (SW trof, flat ser, textook nao blocking) . Maybe hangover Nina effect?

[AtlanticWx]

 

18 minutes ago, WxUSAF said:

You’re not wrong. Most of this discussion is following from one of Webb’s tweets today discussing that -NAO Decembers in Ninos usually suggest persistent -NAO for the whole winter. Even though the EPS plot @CAPE showed above is improved from 0z, it’s not a cold/snow pattern because of that strong -PNA.

-PNA/-NAO is really good for some CAD storms tho. p easy way to score in december if timed right

[brooklynwx99]

3 minutes ago, Ralph Wiggum said:

Looks exactly where last year left off (SW trof, flat ser, textook nao blocking) . Maybe hangover Nina effect?

that's a run-over-run trend. these are the actual 500mb anomalies... the western trough is pretty common in Nino Decembers that move into Phase 3

 

[Eskimo Joe]

The 12z Canadian ensemble would be my preferred evolution. Good Atlantic and Pacific with split flow. The Euro would be an unmitigated disaster and set us up for failure.

[CAPE]

4 minutes ago, Eskimo Joe said:

The 12z Canadian ensemble would be my preferred evolution. Good Atlantic and Pacific with split flow. The Euro would be a disaster and set us up for failure.

It's a long range snapshot on a smoothed ens mean. Chill lol.

[CAPE]

9 minutes ago, Eskimo Joe said:

The 12z Canadian ensemble would be my preferred evolution. Good Atlantic and Pacific with split flow. The Euro would be an unmitigated disaster and set us up for failure.

Here is the pattern progression on the Euro extended based off the 0z run, into mid Dec. Heading towards an unmitigated disaster and ultimate failure?

[Eskimo Joe]

1 minute ago, CAPE said:

Here is the pattern progression on the Euro extended based off the 0z run, into mid Dec. Heading towards an unmitigated disaster and ultimate failure?

West coast trough floods us with Pacific puke. Classic failure mode.

[CAPE]

[Eskimo Joe]

1 minute ago, CAPE said:

 

I love your enthusiasm and willingness to provide deep insight. Don't let my eternal pessimism get you down.

[AtlanticWx]

7 minutes ago, Eskimo Joe said:

West coast trough floods us with Pacific puke. Classic failure mode.

that's a GOA low, which is a classic feature of Ninos. look at the height lines which point upwards over Idaho, that's a decent signal for a ridge in the west this far out with all the smoothed means. i think you need to let go of whatever nina base state panics ur having bc now we're in a solid nino

[CAPE]

Just now, Eskimo Joe said:

I love your enthusiasm and willingness to provide deep insight. Don't let my eternal pessimism get you down.

lmao no chance. you do you dude. we all contribute in our own way.

[CAPE]

4 minutes ago, AtlanticWx said:

that's a GOA low, which is a classic feature of Ninos. look at the height lines which point upwards over Idaho, that's a decent signal for a ridge in the west this far out with all the smoothed means. i think you need to let go of whatever nina base state panics ur having bc now we're in a solid nino

He is focusing too much on the anomalies(pretty colors) instead of the height lines. On LR tools it's the 'general idea'. Some get it, some don't.

[stormy]

After a wonderful rain yesterday, the drought goon returns for the next 15 days.

[Eskimo Joe]

19 minutes ago, CAPE said:

He is focusing too much on the anomalies(pretty colors) instead of the height lines. On LR tools it's the 'general idea'. Some get it, some don't.

I'm smarter than that. Need a more pronounced ridge to scoop that cP air down on us.

[AtlanticWx]

3 minutes ago, Eskimo Joe said:

I'm smarter than that. Need a more pronounced ridge to scoop that cP air down on us.

you will never find a crazy pronounced ridge on a 7 day mean that far out on the weeklies

[North Balti Zen]

39 minutes ago, CAPE said:

Literally every day on this board every winter for years now.

[Stormchaserchuck1]

I think our first flakes are going to wait until that Pacific pattern breaks down.  +EPO is the worst pattern for snow, -PNA the second, and models went big in that direction today. But like I said last night, they are fluctuating big time day-to-day. They had a +NAO in the MR/LR a few days ago which is now a big -NAO. Back to the basics: We have a > +2.0 Nino 3.4 strengthening El Nino happening, so we should favor more +PNA or GOA lows, let's see if models drop the big -PNA/+EPO that they, today, have, if nothing else just because of ENSO. 

[Stormchaserchuck1]

24 minutes ago, AtlanticWx said:

you will never find a crazy pronounced ridge on a 7 day mean that far out on the weeklies

Since 2019, almost every single -NAO has correlated with a +EPO/-PNA, and +NAO's correlating with -EPO/+PNA.. that really holds true in these recent shifts. I think something is happening globally that makes it all run together. I would of course, rather see the +PNA/-EPO/+NAO combo and we can get a Winter like 14-15. 

[Weather Will]

WB Euro weeklies have been consistent about east coast trough developing the third week of December and now showing into the first week of January.  Precip. Anomalies and temps are lining up nicely.  I will stay optimistic about the winter as long as this trend continues.