Stormchaserchuck1

Do you think that models like the EPS are too programmed for it? In researching, I found that Stratosphere warmings in 10mb never exceeded +2500, and we are already at +1600 as of 12/27

I'm not one to give up on snow. It seems like a lot more precipitation is happening, and the possibility for stronger storms. I always thought 09-10 was a step in this direction. You see how on the coast the trend is actually upward. I think the -PNA is the real problem, and that even held in a lot of the early 2000s when we were doing well with snowfall. https://ibb.co/2csFL89 As the pattern relaxes, low's are energized not inland, but off the coast over the water, and the early 2000s were filled with examples of this, where they would track just right off the coast. I don't see that trend as disappearing, I just think it has been a very -PNA for 7 years. In the later part of a -PNA cycle, SE ridges are more dominant.

Why? Most El Nino's have a nasty +PNA by mid-January (historically), this usually correlates to an east coast trough. It seems like as things are happening "a lot of people expected it"

Pretty strong Stratosphere warming already happening in the historical CDC daily dataset https://ibb.co/MRc03C6 The average time-lag of 500mb -NAO effects is +25-30 days, so that give us ~Jan 19-24 as the start of probable -NAO conditions. Here is how the NAO correlates to US temperatures [default positive]: https://ibb.co/S0rqMcL Believe it or not, the Jan 19th date matches exactly when my roll forward Jan 5-13 N. Pacific ridge in ENSO changes/reverses and becomes a +PNA/colder pattern (2 different variables in different region). So I would watch maybe Jan 21st on as a possibility to go colder, and have a wintery period in the east.

I'll include updates about the Stratosphere warming in this thread We are already hitting Stratosphere warming territory, as of Christmas: (as per the method I used to research historical -NAO correlations): https://ibb.co/Htm37sB 12-27 is already pretty strong https://ibb.co/MRc03C6 Dec 25-27 has a normal/average lag to 500mb of +25-30 days. So that makes the highest probability of -NAO conditions to start on Jan 19. Stratosphere warmings at 10mb usually last a total of 15-45 days. This one seems projected on models to go on pretty long.

We are already hitting legit Stratosphere warming territory, as of Christmas https://ibb.co/Htm37sB 12-27 is pretty strong https://ibb.co/MRc03C6

GOA stands for Gulf of Alaska. WC stands for West Coast

GOA ridge, WC trough, ridge overtop here in the east.. no way. bluewave posted something where most of our snows since 09-10 have happened with a ridge in the West as the most dominate N. Hemisphere feature (for NYC at least).

Nice to see the 540 line barely getting here in January as dark purple on that map. TT must use 91-20 averages.

That's what the ENSO analogs show https://ibb.co/xzVYnx5 But this El Nino so far has not really had much of an impact on the N. Pacific 500mb pattern so we'll see https://ibb.co/LxKM678

Look at this massive Pacific ridge on the CPC ensembles https://ibb.co/yQxk7bS I'll bump my roll forward from yesterday since it's trending more probable to happen as a dominant pattern

Coldest day of the year is Jan 27th. Precip does slightly uptick in the 2nd half of Winter vs the 1st.

We just don't do well in trend when there is a High pressure near the Aleutians. As we get closer, The relative SE ridge undercuts and the cold air gets cutoff. I have seen this so much in the last few years, that I would call it a small to no chance that this threat (Jan 7th) becomes snow. We need the Pacific to change. The only thing I can think of is that models have a equilateral wind reversal happening over Nino 3.4, and this is rushing them to develop a -PNA.

A strong High pressure in the N. Pacific ocean during the cold season is not usually an El Nino pattern. Looking at the long range models, we are going to have that feature through Jan 15th, and that is going to give us a net +epo/-pna for Dec 1-Jan 15, which compares to only 2 El Nino Winters: 65-66 and 72-73. If you look at the whole El Nino event to-date, there is no N. Pacific Ocean trough south of Alaska! https://ibb.co/LxKM678 In fact, the strongest pattern in the whole Hemisphere is a ridge over the N. Pacific warm pool (-PDO)! Considering the El Nino is around +2.1c, that's not a high correlation to its normal effects. Models are showing a strong N. Pacific High pressure (-PNA) Jan 5-13 [18z GEFS]: I composed a list of 15 analogs that had a -PNA/El Nino or [minus]+PNA/La Nina during that time, and see that the pattern usually reverses in the N. Pacific Ocean after. The roll-forward shows the Pacific pattern usually flips quickly after 1/14. By 1/19 it's +PNA. And by 1/25 it's -EPO. 500mb roll forward Animation: https://ibb.co/xzVYnx5 So ENSO-weighted analogs show that the N. Pacific pattern we are seeing on LR models is a temporary, and not permanent feature. Let's see if this reversal carries through. Here are US Temps in the roll forward: https://ibb.co/kGL4bZp

The good news is the majority of analogs show that the pattern usually changes shortly thereafter (referring to the N. Pacific ridge Jan 5-13). I took all -PNA in El Nino or Neutral years and minus all +PNA in La Nina or Neutral years since 1948 for that time, and came up with 15 analogs. The roll-forward shows the Pacific pattern usually flips quickly after 1/14. By 1/19 it's +PNA. And by 1/25 it's -EPO. https://ibb.co/xzVYnx5 So ENSO-weighted analogs show that the N. Pacific pattern we are seeing on LR models is a temporary, and not permanent feature. Here are US Temps in the roll forward: https://ibb.co/kGL4bZp

Actually we have a huge N. Pacific ridge on 18z GFS ensembles Jan 5-13. I was about to look up ENSO-matching analogs, but it appears 15-16 does not fit that pattern on those dates.

We had a 30-day Stratosphere warming last Winter Feb 14-March 15. https://ibb.co/601Xr3H It did downwell to the troposphere to effect the NAO https://ibb.co/GT59g8v Here US temperatures for the most historically effected time-lag: https://ibb.co/82qyFTz Before that we had a Stratosphere warming in January 2021 https://ibb.co/JkdhgnK This is how that one effected temps +time https://ibb.co/d0zFmC1 We also had one in January 2019 https://ibb.co/Z6CKVjd Again, a SE ridge pops (+normal-time-to-impact) https://ibb.co/Y8yhTPR Feb 13-March 15 2018 https://ibb.co/BcdvyNd One of our colder ones in the east recently https://ibb.co/pQTCrh9 Really impacted the NAO +time https://ibb.co/TmzxvwT Now I will explain the time-lag: There are great resources through the CDC daily climate composites that allow you to backcheck things going back to 1948: https://psl.noaa.gov/data/composites/day/ In looking at the whole timeset, I found a strong +time correlation to 10mb warmings and -NAO (500mb). It varied at different times in the year: Stratosphere warming Oct 30-Nov 15 has highest -NAO correlation at +45 days (Dec 15-30) Nov 15-30 Stratosphere warming has highest -NAO correlation at +40 days (Dec 25-Jan 10) Dec 1-15 Stratosphere warming has highest -NAO correlation at +35 days (Jan 5-20) Dec 15-30 Stratosphere warming has highest -NAO correlation at +30 days (Jan 15-30) Jan 1-15 Stratosphere warming has highest -NAO correlation at +25 days (Jan 25-Feb 5) Jan 15-30 Stratosphere warming has highest -NAO correlation at +20 days (Feb 5-20) Feb 1-15 Stratosphere warming has highest -NAO correlation at +20 days (Feb 20- Mar 5) Feb 15-Mar2 Stratosphere warming has highest -NAO correlation at +15 days (Mar 1-15) March 1-15 Stratosphere warming has highest -NAO correlation at +15 days (March 15-30) etc.. They vary in effects to the troposphere at different times of the cold season, but I found I strong correlation +time (since 1948). Here are the NAO effects on our temperature +0Day (+40-50% correlation): https://ibb.co/jDLnWvp Since 2013, and more so 2019, I have noticed a correlation between -NAO and +epo/-pna, and visa-versa. The correlation is ~0.30 since 2013, and ~0.40 since 2019. Early in December, a strong -NAO built, and the correlation held in an El Nino. Models have 10mb warming peaking around Jan 6th, which would make Jan 25-30 ripe for -NAO impacts, and maybe, therefore, a -pna? The fact that it's an El Nino makes it 75/25 more likely to have a +PNA at that time so we will see what happens..

The N. Pacific ridge is not necessarily a global warming variable https://ibb.co/4TTP0Wm

Yeah we are right in the heart of this -PDO phase huh. Since 1998 and more so, 2008. This is why I'm worried February could be a -PNA month, it has been the hardest hit month of the current cycle. (v ignore some of my weird comments) The last +PDO La Nina was 1983-84.. I don't know here you go, agreement. 1 La Nina +PDO analogs since 1948: https://ibb.co/txmC0Sf (I think we were due for some -pdo/el nino's, +pdo/la nina's, and also due for some ENSO events that don't impact the atmosphere so completely)

They are doing this because -PNA is a strong precip-correlation in January https://ibb.co/vQZHtKJ I guess they figure there is a chance that the storm will run into cooler temperatures. This is something I do not agree with. I have seen many times, enough to make it a strong indication, over the last few years that when there is a high pressure in the N. Pacific ocean and a storm cutting up from the south, the cold air becomes cutoff (underrunning SE ridge) and it's mostly rain. This is a trend that does not happen (toward snow) because, it's Pacific driven https://ibb.co/nD74TV3

This El Nino is not really effecting the N. Pacific like other ENSO events. For the Winter pattern Dec 1-Jan 15 we are going to have a net +epo/-pna https://ibb.co/qBFx1bx Here is since the event began https://ibb.co/jyfgngk ^that's during this whole El Nino. no negative heights until you get to Alaska.

The December roll forward of +EPO pattern (strongest N. Hemisphere pattern) is doing really well. I said before that a 20-year composite/80 giving +4-6F anomalies for January is/was a strong signal. I posted this a week ago, but here is the updated December pattern: https://ibb.co/thgCjWv EPO analogs https://ibb.co/xJgLyJv The January roll-forward was an interesting SE ridge signal, interesting because El Nino's are usually opposite https://ibb.co/GHPyQDC Here was the December temp map https://ibb.co/fFw0k4K That +2 to +3c was interesting for January because "a lot of December El Nino's are warm".. well in January they favor an opposite pattern, but not in the strong-EPO-roll forwards. Now models are showing a strong N. Pacific High January 5-12, which again is a unique signal. The +EPO-Dec roll forward does cool down for February: https://ibb.co/Mfg08FR I would guess it goes cooler Jan 25-Feb 15 but I have not done the specific day-by-day charting. It also rolls forward to a warm March fwiw: https://ibb.co/gV6DwZj

I used up my attachment space after like 600 posts. Most of what I want to show is weather research, and I have been posting links, but I think it could be better if there was space to post here directly, plus it would be stored on the board. Just a request. Not a big deal if you don't have the space to give me more space.

That was definitely part of some colder Winters. https://ibb.co/McvQmYW

Maybe not, but in an El Nino our chances are better.