NittanyWx

You're comparing a short interval of time to a weekly mean h5 view though. The source region is and was still garbage.

I think you misunderstood what I'm saying. I'm saying if the weeklies are already seeing it, as a forecaster are you adding any skill on top of it by coming out and saying 'this SSW will dramatically change things'...I'd argue going counter to the weeklies in the dramatically colder direction for example could end up burning you a lot of the time.

I can't blame weenies for being frustrated at a lot of early Jan forecasts. It will end up warmer than many were preaching based on the H5 look of the Euro weeklies. I personally am not canceling winter and haven't seen many do that outside of complaining about mild weather. but this is another case of 'know your source' when viewing h5 forecasts in the week 3-4 range. That said, I think the erosion of mild Pac air is somewhat less hostile than what we're gettng in early Jan

I mean, it can be something that helps turnaround...maybe? It can be relevant to the pattern relative to blocking in the right set of circumstances. But I think the better question is 'are the weeklies already seeing that' in their week 3-5 timelines and further are you doing a better job determining regional temp anomaly distribution than the weeklies are relying heavily on SSW as the basis for your view. Many times the climate models are taking a strato warming event and are assimilating it into those forecasts. So I'm not sure how much forecasting edge you're actually gaining from pointing it out.

It's something to discuss, but it's also only relevant for Feb...maybe...if it actually happens as progged. There's no issue talking about it, but a lot of people do tend to overhype the correlation to 2m temp, and specifically to 2m temp in the east.

You see a very small sliver of the pro's. Social media pros tend to skew cold because it drives interactions. I don't view Bustardi as an operational met anymore so much as a political pundit hocking books. He has long past his expiration date on reliable forecaster in the long range and a lot of folks have wised up to it. Margavage was in school when I was and flunked out, now returns as the 'cold and snow' guy and gets a following. There are a lot of good mets around, a lot, who's opinion I value and respect. Some of them were cold 1h Jan, many were not. But they're not gonna be the loudest voice on twitter.

Just personally I care way more about what's happening upstream right now given lack of carpet and atrocious source region. Think the 'way out' of this very mild pattern has to be this +EPO/-PNA combo, which likely means locally it's mild outside of a transient period around the 5-7 and cuts off the Pac flow into NW Canada for a minute. Then when you return to a more +PNA setup given background standing wave pattern you're advecting air that isn't just mild mP that has flooded into NW Canada.

You may have found a universally acceptable definition of persistence. Edit: card carrying member of #TeamWCanFirst

I suspect you will end up finding progression here in these VP anomalies as well. Particularly as the IOD has collapsed and there's a smoothing of ocean temperature anomalies between WIO and EIO.

This was a fun debate earlier in December.

Source region remains an inhibitor to anything other than transient early January cool shots surrounded by warmth. Keeping a side eye on the Jan 5-7 window in the event this low amps a bit more, but outside of that 'know your source' remains quite prudent. Looking bigger picture, seeing signs of the erosion of Pac air upstream into W Canada deeper into Jan. Should be less hostile then. But as far as this early Jan period goes, the book was written early. A modest h5 improvement, but lack of source air first week.

The GFS Ens is going to again beat the EC Ens in this post-Christmas period. Both will end up too cold.

I think this was well telegraphed personally. In years where you 'got out of it' after a very mild start, this was normally the step change observed.

Thoughts today: The lack of source region remains a barrier to significant cold despite h5 improvements. As such, first 5 days of Jan should average above normal before a transient cooler period 5-7th. Think the risk is cold air overdone by modeling in extended range and HP rolls forward less intense due to lack of snowcover and Pacific air contributing to that issue. Locally, we'd need to thread a needle for a significant snow and you only have a couple windows where I see that as possible early January. As I've said several times now, source is still vitally important. And we are in an improved h5 pattern with marginal source region through the first 7 days of Jan. That's not a death sentence for snow, but margin of error is slim. First period of interest would be Jan 5-7 range as some HP in Canada and a wave in the southern stream moving northward. I flagged this as a period of potential interest last week and thoughts haven't changed on it. Old adage is 'WAA waits for no man' but this is a situation where if you can avoid a coastal bomb you could get an overrunning situation into NE Canadian high pressure if the cards on the table lay out properly. Several things need to go right, theyre not all 'right' as of today, but that may change. Big picture, thinking this is a multi step process moving forward whereby the upper level pattern shift will be most notable during the Jan 8-15 window as we scour out some Pac air in North America, TPV retrograde westward (slowly), PNA drops and EPO rises. That should, in theory, start the process of allowing for some carpet to be laid in the Canadian prairies and upper Midwest later in the month. It's not brutally cold, but it's a way to begin to scour some of the much above normal temps in time. It'll be stormy, but mild here I think during that second week of Jan. Could have some much above normal temp days. Could you see something in that window of transition? Perhaps, but again need several things to go right and big coastals are a no go for snow here in this window. I expect polar regions to be less hostile heading into mid-late month, but the Pac still hostile for the bulk of early Jan. That brings us to the MLK weekend whereby you're looking for some of this cooler air to potentially migrate S/E ward as PNA rises and board resets towards more traditional Nino with potentially some blocking. Maybe. I think you've got a lot more reasons to be optimistic after MLK than before, with the caveat that you'd hope the Pac jet isn't as hostile as it has been if you're a snow lover. As an aside, I'm not considering any potential Strato interaction on this pattern until perhaps February, if at all. I just view any potential 'help' there as supportive of blocking and not necessarily supporting a Pac change.

MJO shouldn't be weenied for this one. He's right that most are calling for a warming event and potential split. It does look valid and will qualify as an SSW event in all likelihood. What will be overhyped is the correlation between SSW and t2m in the east. SSW events are essentially a correlation of a correlation to 2m temps. SSW inducrd PV displacement and splits are correlated to periods of more blocking which is correlated to colder temps in the mid latitudes of varying intensity and regionally/unevenly distributed. That correlation to temperatures is mostly 3-4 weeks after event. So this would in theory increase colder odds for the mid latitudes in February. But that doesn't necessarily mean colder in the northeast. It might, but it's not guaranteed. Historically splits work better for NA in analogs....but theres a huge caveat that the pac jet will need to relax and the EPO will need to be way less positive that it is right now. In short, its a situation where one of the factors we track in the weather becomes less hostile in theory to cold in the mid-latitudes. That said, we don't live at 10-50mb level, so it's one piece of a large puzzle.

Not enough cold air to tap into

I think we have different definitions of excited

For what it's worth, these models have no real E Canadian HP signal until very briefly around the 5th. So if we were to get any storm ahead of that, regardless if it's a lake cutter or not, you'd have a big issue with cold air supply. If you were to get some energy out of the southern stream around then while that high is retreating, there's a small potential window around than Jan 4-6. As noted, however, I tend to think in regimes like this where h5 is favorable but source air is not, risk is HP/cold air associated with it gets overdone extended range.

The NAO difference is actually fairly marginal. Synoptically most have a piece of the PV near or just north of the Davis Strait. There's no real Atlantic block of note in the traditional sense, just heights building Iceland/E of Greenland which is of little significance to us.

The IOD seasonal collapse is consistent with past years. Even high amplitude IOD patterns collapse by the New Year almost without fail. So, in time, the jet will retract and there will be a retrograding PNA area ridge setting up. At that point with PV consolidation you'd hope that some form of wave breaking can perturb the PV and displace it towards this side of the pole for deeper into January to at least provide some chill to tap into and perhaps start building some snowpack in Canada in due time. Until that source is resolved how I view these setups for snow: HP/cold will likely be overdone on modeling without a true snowpack build in the extended range. So, generally, less is more when it'll come to coastals if/until this source airmass problem is resolved. Deepening coastals will likely be primarily rain producers where overrunning events or even clippers have the better potential to deliver wintery results.

Just a note that the GFS Ens has been posting higher skill scores in the 6-10 at 2m and suspect the EC Ens surface reflections will end up a couple degrees too cold. Sadly even the GFS Op has had less of a cold bias past 3 weeks. That said, do believe the base state is changing from December. Not a great source region still, but not as dire as late Dec.

Ok, get what you're saying now. Only reason I'm kinda hammering on this tropical forcing vs model T2m point is because I think it was a situation, and clear a clear one at that, that we can learn from as forecasters and apply to future predictions. Multi-faceted signal that - even in a situation where tropics were underamped - the model was still able to lead you to a place where you'd be happy going warm to very warm week 3/4.

You do follow Joe. I know because he tweeted almost verbatim what you wrote. I do not follow Greta Thunberg because she isn't a forecaster or really relevant at all to what I do.

You're ascribing PV displacement to what? Just the tropics? Because I vehemently disagree with that idea if you are. You've got 3 of the factors covered, but saying 'MJO inherent biases' is still a misread on the situation. Because the 'MJO inherent biases' were part of that weekly EC ens first week of Dec...and the model still went torch...and we still ended up in a torch nationally.

Bro is a comedy act. In commodities (where I work) we have people taking positions on buying/selling nat gas on the basis of the weather forecast, production and implied demand. Those people who sold this market with the view of the weather being bearish this month are pretty happy. Those who bought it are pretty unhappy. Trading is capitalism. Weather trading is capitalism. The beautiful thing about these markets is they tell you who's right and who's wrong. And you, my friend, would be broke if you tried to trade off your politics. Weather knows no politics, it just is. And this year, it just is the warmest we've had in our climatic record on a global basis (aka 1850). And that includes cold China in case you're wondering. Anyway, back to dissecting late Dec forecast busts.