Stormchaserchuck1

Yup, two warm days, and the LR look for significantly below average/-NAO is gone.. Models initialize current conditions out. For example, if they are saying the LR is going to be severely cold, and first you have two 70+ degrees, you should figure that during those two days the LR models are going to completely lose the cold signal.

Easily coasting up to 76 here in northern MD

Denver area continues to do well with snowfall. They are in a sweet spot with the warming, like NYC was 2010-2015. Meanwhile, we are almost 80 in Baltimore. https://ibb.co/3rGsDRd

The sun is pretty hot today. Like, hot. This thing is taking over pretty quickly.

Pretty awesome pattern for below average here: https://ibb.co/bsDzrQg Too bad this didn't occur in the Winter time.. The Pacific pattern actually changes this weekend, and sometimes when we have cold the day of (warm the day of too), models go more aggressive on the same pattern initialized out down the road. I think we can hold out some hope for some snow flakes in northern MD by the end of March.. With that being said, it is 70 degrees out the next 2 days, and the PDO still has not changed, so the same model trend that has occurred all Winter has a chance to repeat in the next few days, going not as aggressive with the cold in the LR.. If it holds though, that's a really nice look at least for some below average conditions in the NE for the last few days of March and into early April.. We do have a strong 10mb warming going on now, so that at least supports what the model shows (average time lag at this time of the year is +10-15 days)..

Upon further review, there is something wrong with the CPC's NAO calculation. This is not a strongly positive NAO: Looking back over past Winter's, there were a few -NAO's in there too, that were deemed to be positive. The NAO is calculated by sea-level pressure differences between Iceland and the Azores. High up top, Low at the bottom, is -NAO. Low at the top, High pressure bottom is +NAO.

The NAO is just not sustaining negative lately. Winter 23-24: Dec 2023 +1.94 Jan 2024 +0.21 Feb 2024 +1.09 Since Dec 2013, only 5 Winter months negative (41/46 positive) Dec 2011 2.52 2012 1.17 0.42 1.27 Dec 0.17 2013 0.35 -0.45 -1.61 Dec 0.95 2014 0.29 1.34 0.80 Dec 1.86 2015 1.79 1.32 1.45 Dec 2.24 2016 0.12 1.58 0.73 Dec 0.48 2017 0.48 1.00 0.74 Dec 0.88 2018 1.44 1.58 -0.93 Dec 0.61 2019 0.59 0.29 1.23 Dec 1.20 2020 1.34 1.26 1.01 Dec -0.30 2021 -1.11 0.14 0.73 Dec 0.29 2022 1.08 1.68 0.77 Dec -0.15 2023 1.25 0.92 -1.11 Dec 1.94 2024 0.21 1.09 Never going below -1.11 for the Winter month since Dec 2013. Since Dec 2013, 16 Winter months over +1.11! (16-0) A lot of that has to do with the southern part of the NAO measurement, near the Azores, and spread out over the N. Central Atlantic Ocean.

You did very well, congrats. That's 2 Winter's in a row I think. I remember thinking that you would be too warm last Winter, but it verified.

Not only that, but the warmth seems to be accelerating! Since the satellite era in 1948, the N. Pacific Ocean High pressure for Feb-March (-PNA) is going to be after this March, a whole +25% over any 500mb anomaly on record (for a 2-month period, spanning 7 years). But perhaps a side point is, that is a pattern. It's not random, general warming happening, it's something causing -PNA's to be more frequent in Feb-March. I would put money on next Feb-March also featuring this -PNA, SE ridge pattern.

Here's your -AO look: I thought a Strong El Nino/Strong -QBO combo would do that.. we had a few Stratosphere warmings. The Pacific Ocean pattern kept North America warmer..

I nailed it.. there was more -PNA in February than +PNA The big Aleutian low that models were showing ended up in the Bering Strait, which isn't really the same thing. Persistence won.

I think the rotation of the Earth has slowed a little.. we are seeing more High pressure systems. land vs water friction also seems to be a little greater (cold coming more from Canada vs 50/50 low cold).

The PDO talk drives me crazy. It's not some independent thing, It's feedback from previous patterns. Air is so much lighter than water, so it changes first.. then the water warms/cools. All that's being spotted with the PDO is pattern marks, some alternate mechanism, unless the Pacific rim is active or something..

It looks like we're going to be too far south for severe wx tomorrow.. an El Nino February Chicago's under a tornado watch, and the radar looks impressive there

CPC is pretty big on the +EPO pattern sticking around https://ibb.co/37rmSNg

It did. https://origin.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ONI_v5.php Since 1948, The 4 times we had a OND ONI +2.0 or greater, we had a La Nina the following OND. One of those was the strongest La Nina on record (1973).

I thought it was telling when Boston only had 2" of snow in the core of Winter, I think it was either 17-18, or 19-20. The jet stream has been lifting north for sure..

12z GFS ensembles trended much more -NAO, starting the first few days of March. We had a minor Stratosphere warming Feb 15-23, so the beginning of March actually fits the average lag for warmings at this time of year.. interesting that standard methods would have got it right, and not models until now.. problem for snow/cold is the Pacific pattern is bad for the foreseeable future..

18z GEFS tries to develop a west-based -NAO block by mid-March. Let's see if the Pacific pattern breaks down shortly after.. I think if we have a big -NAO develop, the Pacific will correlate and -PNA/+EPO will prevail..

Very interesting that, that's when the N. Pacific High has been fluxing: This 7-year trend now, is record breaking ('64-69 -NAO comes in 2nd, at 80% of the anomaly). 2-months including March is also record breaking for a 6/7 year stretch.

Yeah, PDO's usually go in the direction of ENSO state like 85% of the time. Another thing too is, this La Nina is already heavily supporting -PNA.. Since the subsurface cooled, and the SOI flipped, this new High pressure pattern took over in the N. Pacific. so if that trend continues through the Spring and Summer, which I think it will, the PDO should drop further.

The crazy thing about this map and us being the 3rd warmest is, it looks like it's a -AO pattern! It was once theorized that AO was our #1 pattern for warm and cold, but there have been some warm -AO's the last few Winters.. I think the key these days is more on the Pacific side. The circulation between the Poles and the mid-latitudes seems to have quieted down some.. it's more about having more low pressures around the Earth at your latitude.

The thing about the expanded Hadley Cell is, what's causing it? For the Hadley cell to expand, another cell has to contract. You could say that the +AMO and -PDO favor more mid-latitude High pressures. I also think it could come from more La Nina patterns that we have seen (almost 2:1), since sunspots started quieting down in the 1990s? In global warming, the poles are hit the hardest, but it seems like a La Nina pattern to me. That doesn't mean general warming still isn't occurring.. it is, and actually, almost exponentially.

Here is what I accidentaly posted in the long range thread.. I left it there because PSUhoffman replied quoting it. I think the reason for less clippers and Miller A's is lack of +PNA, although even when that pattern is present, those two storm types are happening about 30% less of the time. Basically.. I don't have a good answer for you. The pattern has been more zonal, vs major troughs.. now, the -PNA that we have seen since 1998 and then 3x more since 2016 is a real anomaly, and not a product of global warming.

We had a minor 10mb warming Feb 15-23 The estimated time to impact, March 3-10, looks very warm on current models in the Eastern, US (No +NAO though, it's because of +EPO/-PNA). We may get cold shots in the West during that time. This was our 3rd 10mb warming event of the Winter season. I believe models were showing a 4th warming event starting after ~March 5.