NittanyWx

Lol what? I gotta ask, who told you we have 'no idea' of what happened more than 150 years ago?

It's not unique to NY either. Single day rainfall records are being broken and an increasing rate over the past 20 years. It's one of the cleaner climate change signals we have and passes the scientific sniff test.

The more 'favorable' VP anoms did progress as expected. I do think the MJO signal was overamped and overhyped as a function of the pair of tropical cyclones and a Kelvin wave, but this was a pretty clean 200mb VP signal. I don't think this failed in that sense.

Yeah for Feb sure, was more talking Jan since that's where we kicked the can to at this point.

Just curious why you think it's the strato that's needed? We've had blocking over the pole and SSW's are mostly viewed as a way to weaken the PV to allow for more blocking. There's been the -AO, there's been a -NAO...to me this needs to be some sort of wave breaking signature to change things in the Pacific since default state in Nino years like this is +PNA. PV splits have a loose correlation to cold roughly 24 days after they occur, but that would then be kicking the can more to Feb, no? If you're looking for Jan help it's gonna need to be some combo of Pac changes in conjunction with dislodging some cooler air. I think you're on the right track with the idea of jet retraction, since in my mind the way for this to happen is retrograding +PNA which amps into AK and finally dislodges some cooler air and aims it towards NA.

Yes I agree its a better look synoptically in terms of shutting off the Pac flow and potentially dislodging something colder out of the artic and pushing it towards this side of the pole. Maybe not hammer cold, but an erosion of the much above. When we spoke 10 ish days ago, i felt the way to do this was with some sort of PNA retro, amp into AK after jet retraction and the Kara Sea piece allowing for some cold to be able to be tapped. This is in a way similar to that idea and an important step in this process. Split flow would increse the odds that pattern would deliver some sort of storm with as you head into that Jan 5-15 window. Let's see if it rolls forward. As I said before, I'm in the agnostic camp at that range.

Couple things...first, you had a midcon snowpack then: Vs now: And really my point a couple weeks ago was 'what air are you advecting?' when you went back to a +PNA for that Christmas week. Not saying it can't snow from a one off, but I am saying this current setup that was shown for the last week of Dec wasn't a modeling error. It actually looks like a really good forecast. So now it's really to me about finding a way to dislodge that extremely +EPO and also weaken that Pac jet extension. Yeah i don't think climo supports the Pac jet staying extended for long, but I still am of the belief that some source region is needed after the Pac air floods most of NA. It's possible, but I really do believe if you want a prolonged snowier period in this type of climate you need some Canadian HP and it would help to have some form on a midcon snowpack that is usable in a baseline +PNA scenario. I'm agnostic at the moment. Think both things are possible, but I'm not at the probable stage until I see some changes in the AK region.

Just to circle back on the source region/weeklies discussion from last week: This look from the EC Ens mid 11-15 day now looks a lot like the weeklies from a couple weeks back at H5 Now at the time there was debate about MJO being the precursor to find cold in this pattern. However, as discussed then, the concern was that there wasn't cold in western Canada to be displaced and a lack of snowcover would modulate a very weak cP airmass in the event of a +PNA. The 2m temps from the EC Weekly for that period: So in my view, this strong + EPO forecast and roll forward was pretty well advertised. And shouldn't come as too much of a surprise given source airmass and seasonal factors tending to support that idea in December strong Nino's. The models are forecasting the MJO progression in both of these cases. So the use case of 'I can forecast the anomaly better than the model because I feel the model isn't seeing the true reflecfion of the MJO' actually led to negative forecast skill. Utilizing the weeklies in this case would've been prudent and understanding the source region wasn't sufficient are and were very important pieces of this puzzle.

He's lost the energy audience because they've been burned by him calling 55 of the past 2 cold shots.

The h5 charts at the end of the EC Ens don't look that much different from what the EC weeklies were showing in that post Christmas time period. Aleutian low, +EPO, +PNA but no source air. Flagged it at the time that this wasnt gonna be the cold look people thought it would be, but if that ends up rolling forward it's actually a pretty decent forecast from the weeklies.

It's not restricted to the warmer MJO phases. In general, our Oceans are very, very warm. We are increasingly breaking single day precipitation event records as a result of warmer temperatures as a consequence of, in part, higher oceanic heat content.

LFCLI30

This is very meta for me. I started as a teenager posting on Evans forum, went to Tristate and @jm1220 who I know personally and at Penn St, Adam and Tech and Mets and all those guys. Would have meteorologists chime in too...Rich Hoffman, Mike Ekster, Goodman, Craig Allen etc etc...those guys were invaluable to my understanding and building a foundation of knowledge. Big part of the reason I'm doing this professionally now is because of the online community then. Was constructive, learned a ton. I wish folks talked over each other less, it's much more combative now than it used to be. There would be arguments for sure, there would be weenies calling weenies a weenie. But the pros would kind of calm the masses and steer the discussion.

Long may this continue. This is an opportunity for market participants.

Intraseasonal variability in a year where we're a lot of extremes to the wet/dry side for several reasons isn't necessarily predictive in my mind. Patterns are quite amplified this year. I forecast globally and I'm seeing records fall way more often this year than I did in 2015. Which is a bit surprising to me.

AG2 has solid meteorologists working for them. They got too cute wirh their forecast, went pure academia focus instead of common sense 'high correlation, high probability' forecasting. It burned them. The other ones are mostly twitter noise for people who want to hype cold, but people do trade them and you see that creep into more reputable forecasters reports sometimes because people ask about it.

So I get exposed to a lot of different weather views in the space I work in and there were a lot of meteorologists and social mediarologists trying to downplay Nino influences this month. I was forwarded some stuff from: Direct Weather, Joe Bastardi, BAMWX, Mark Margavage, Atmospheric G2 and several other sources that were pumping up cold risk in the back half of December after a mild start. AG2 had some tweets comparing this to 09-10 because the October VP200 pattern wasn't canonical Nino and therefore December wouldn't be. It was out there. Maybe not here on this forum, but a surprising amount of folks tried to reinvent the wheel on their December US forecasts amid uncooperative signals left and right

When I'm talking about source region, I'm not talking about extreme arctic air. One of the challenges with airmasses from the north and west is that these airmasses can weaken over time when there isn't sufficient snow-cover. Looking at snow-cover anomalies and the Chinook showing up in the extended range...I'm struggling to find the snowpack build right now and a material change in that scenario. So that means any Continental polar airmass loses punch as it advects southeastward. A +PNA with no snowcover and cP airmass that doesn't have much of a cold punch to begin with weakens chances for snow. So what I'm looking for, and why I keep harping on the need for source, is to mitigate the risk of an empty trough and no real source for cold to accompany any coastal storm if and when El Nino forcing become a dominant driver again in the mid-lats and the seasonal +PNA trend re-establishes.

We're thinking alike

All about source region.

There's a source region problem. Perhaps that Kara-Siberia ridge starts dislodging some cooler air towards AK/NW Canada that can be tapped into at a later date when +PNA base state returns.

By the way, the VP200 Hovmollers are already in 'favorable' territory inside the 15 day. So the models are already 'seeing' the MJO

I will continue to harp on about the source region until it's resolved. It's the biggest inhibitor to anything other than a transient cool period right now. Kara Sea ridge developing 11-15 day should shunt some cooler air on this side of the pole, primarily focused over Alaska and hopefully some of NW Canada. For significant storm odds to increase along with a helpful airmass with it, this period would hopefully include some cold air draining into W Canada. At that point you'd look for a baseline Nino +PNA to re emerge which would, in theory, be the timing when things would line up for something more significant.

Thinking is for a transient few cooler days around mid month sandwiched around warmer ones. I still don't see permanent blowtorch, though I do think the post cool period could produce several much above normal days.

CPC did/does some work on ENSO and snowfall. The problem is the composites haven't updated since 2010, so it's a bit outdated.