Stormchaserchuck1

The last 6 Winter's, we have had -PNA's a greater % of the time, in 3 month periods, then the last 7 months, since the El Nino developed. (I'm quantifying that 1/10 chance, and saying if you base on current probability for PNA it's about 1/3 of the 5/7 recently (5/21).

For reference, Stratosphere warmings average "downwell" time to effect Winter -AO: Oct 15-30: +60 days (Dec 15-30 -AO correlation) Oct 30-Nov 15: +45 days (Dec 15-30 -AO correlation) Nov 15-30: +40 days (Dec 25-Jan 10 -AO correlation) Dec 1-15: +35 days (Jan 5-Jan 20 -AO correlation) Dec 15-30: +30 days (Jan 15-30 -AO correlation) Jan 1-15: +25 days (Jan 25- Feb 5 -AO correlation) Jan 15-30: +20 days (Feb 5-20 -AO correlation) Feb 1-15: +15 days (Feb 15-Mar 2 -AO correlation) Feb 15-Mar 2: +15 days (Mar 1-15 -AO correlation) Mar 1-30: +10-15 days (Mar 10-Apr 15 -AO correlation) [CDC daily climate composite maps day-by-day going back to 1948.] Oct 30mb QBO should come in the next few days. Sept was -13, and down 5 from September, so Nov should come in more negative. <-10 30mb QBO and El Nino correlate strongly with Winter Stratosphere warmings (I think there is a >60% +10mb Winter correlation (NDJFM), and >+10 30mb QBO and La Nina has a >60% -10mb Winter correlation (NDJFM)). Strong 10mb vortex (Stratosphere cooling) has a +0-Day correlation to +AO from Oct 30 - Apr 5 (all Winter), no lagtime. The images posted earlier in this thread of a cold 10mb are correlating with MR/LR models showing 500mb +NAO.

We have been in this weird pattern of -EPO's and +PNA's happening with +NAO, and +EPO's and -PNA's happening with -NAO's. It's had a greater than 0.40 correlation since 2013, and 0.50 since 2019. I think our best pattern is the -EPO/+PNA/+NAO like 13-14 and 14-15, so I would watch out for that pattern probably for our snow this year. Stratosphere warmings could throw a wrench in that, I don't know how the Pacific would react or correlate in that state.

I liked the outlook. Easy to read or browse through. One point I would like to make is that things like PNA or NAO impact PDO and AMO in now-time. In other words, a +PNA Winter Dec-Feb is more likely to produce +PDO. Because of this, unless there is some alter pattern happening with the future progression of water currents, the Fall period is these best to roll forward future 500mb patterns. I think I found in the past that Sept-Nov PDO had higher than random correlation to Winter PNA, but I'm not 100% sure. I mostly agree with your temperatures, snowfall, and precip, although snowfall could go higher, given how it's solidly El Nino/max -QBO (together), and our above average precip pattern this year and for the last few years. I average 32" and the El Nino/max -QBO gives me a 40-60" range to start with, using years like 14-15.

Also, 2-3 days of cold then it's gone for 15 days. Nice Aleutian High popping up in a week. The pattern is showing signs of continuum imo. We have seen more +PNA's since the El Nino developed in April, but they are often transitory, and short lived. Will see if that trend continues.

I'm not so sold on a cold February. The last 6 February's have seen an abnormally strong -PNA, greater than you would even expect in La Nina. It's hard to imagine the pattern is suddenly going to reverse this year in El Nino, when there are no strong N Hemisphere pattern drivers right now. https://ibb.co/hysBNQj It might be one of those cases where December and February switch roles in the PNA region.

0.54 SD, at -0.05, so 50% chance of DJFM NAO range of -0.59 to +0.49, as per N. Atl SST theory [CPC].

I found that October is the only month of the year that doesn't have a +correlation to Winter NAO. There was actually a slight opposite correlation from October to DJFM at I think 52% (75 years).

The Strong Nino = warm makes no sense. Everyone is stuck on the 8-10 analog composite showing so. Why don't Strong La Nina's produce cold lol

We actually saw a drastic shift and difference in the Pacific 500mb from when the El Nino developed this year to before. +PNA is the signal going forward.

13-14 and 14-15 are decent analogs, I think (+pna, -epo, +nao). 14-15 was more +pna than 13-14, you can see how the Nino had impact.

Yeah, they do the same thing every year.. TV mets. I've seen those maps year after year. It also seems everyone's forecast looks similar to NOAA's.

He's low. -PNA's have been hard to develop since the El Nino began. I think we are looking at a neutral to +PNA Winter. Maybe +NAO when there is no Stratospheric warming involved.

The drifts were really something in the Blizzard of '96. I remember crawling up hills to get to the house in 1-2" of ice in '93. I may classify that as a cold Winter

They just flip-out the entire pattern completely. I've seen this especially with Aleutian High's, they will show +300dm on the ensemble mean then the next day it's +50dm, some -epo's, some +pna's, but not wanting to organize in the -PNA region. I've been watching models to 15-day for 5 straight years, and it's never varied so much as this year, and since the El Nino started getting strong. I'm not saying it's going to produce more cold, just that these usually reliable time indicators are verifying much lower. I was getting a +200dm -PNA signal and -200dm +NAO for the 2nd week of Nov, now it's "sheared out" to almost nothing. Just been interesting to watch a random model error consistently happen. (They used to jump from 100dm to 80dm max, now it's like 100dm to 20-40dm).

Models have been busting on warmer patterns like crazy. Seen quite a few major adjustments in the last few months. Since the El Nino began this year, LR model accuracy went down like 40%, especially leading to the more extended period..

I still contest that Greenland troughs are correlating with troughs over the EC, and Greenland ridges are correlating with SE ridges. 13-14, 14-15 story never went away.

95-96 was our last "dry snow" significant winter.

92-93 was a subsurface Weak El Nino. The MEI seems to match the subsurface more than any other ENSO measurement (from what I've seen).

Just like all the other seasonal models, they project out what the current conditions are.

Definitely a warm signal the 2nd week of November. https://ibb.co/NZvcS56

Subsurface is going completely warm mostly throughout for the first time of the event. https://ibb.co/PgkZjgH https://ibb.co/khdBkbZ I think it will be less likely that we see -PNA going into December, despite SSTs.

Even in the Summer a ridge over AK produces cold the EC. You can say it's little south and +NAO amped too, but most of the time a Pacific like this will deliver cold. The low north of Hawaii is in the perfect place too, albeit not very strong.

The 80 degree ridge isn't from the Pacific, ridge over AK and low north of Hawaii is a cold pattern, most of the time. It's a rogue SE ridge, like March 2023.

I wonder if we'll get late November snow this year. It's been a persistent pattern of a trough over the EC 75% of the time since the Spring, so that may carry. I don't really agree with everyone saying warm November and December. Why are Nino's warm in December? They don't know. It just lack of a big dataset, plus La Nina's don't follow the opposite route. I would say 70% chance it's cooler (<+2F) in late Nov and December just carrying forward the conditions of this year. The pattern is quick, but it was a "cooler Summer", "on-time Fall" "on-time Spring", for the most part.. 4-5 days of really warm this week, but it's still -EPO and somewhat +PNA in the pacific (more rogue SE ridge happening than index correlated).