kazimirkai

I mean yeah, deriving the effect of an SSW is a much more complex problem, but no one's debating whether or not it will occur. That's what I find comical about this post.

Lol what's nail-biting about it? Every single ensemble member supports it and about 90% are on board for a full reversal. Seems a bit clickbaity

Well it's pretty normal to expect that the MJO wouldn't reach phase 8 in a la-niña situation with base easterlies, but forecasts change. Still tough to say if it'll stay there long but that seems to be the crux of the change in forecasts over the past week or so.

I mean this seems pretty reasonable. Was at stony brook for the last four years and we got literally one decent snowstorm during that whole period. I certainly related to this sentiment coming from upstate New York.

If you ask me we've already sufficiently met the criteria or an early winter in the east so some relative warmth over the next two or three weeks feels like an appropriate 'balance'. Here's a comparison of seasonal snowfall vs last year at this time. Only the coastal and mid-atlantic areas that have missed out so far.

Ill take it November 2018 and December 2019 are anomalies then?

That's an improvement on the euro since yesterday, OLR mins closer to the dateline and all. Here's a semblance of what that transition might look like. Pretty hard to get those strong westerlies in the phase 8 map with la niña easterlies so we'll see how they contend. Id be surprised if the MJO stayes in 8 for long but we'll see if there's some constructive interference with easterly eq. rossby to prolong convection in the region a bit. That would be best cast scenario

It does seem like this event is increasingly projected to pretty quickly rebound by mid month Dec. We'll see if the MJO has anything up its sleeve regarding a 2000 situation

Well the low-frequency background state shows low heights in the east during the time period where MJO is most likely not projecting so the pattern is likely to stay generally seasonal. I wouldn't expect a massive warmup or anything but more of a moderation

Yeah my professor was highlighting the off-the-scale wind anomaly within the last few days. He does think that the MJO will wrap back around before reaching 8 and usher in a more central US trough for the latter part of December. Fairly confident that the beginning will be cold though.

Pretty uncommon for short-range oscillations like the PNA to remain strongly in either state for a whole month. I wouldn't put too much weight on this negative flip, though it might explain the great lakes track that seems more likely during the latter half of nov. and perhaps during the first week of dec.

Warm waters into the W pac. from this westerly wind burst are priming the ENSO for a real shift come the next big event.

This seems reasonable. I think this early December cold wave is mainly driven by high frequency signals, mainly the 7 phase MJO, but i think its too early for the SSW to be having any impact. Roundy thinks there will be some warmth in late December as the MJO move back towards 1 and 2 (abeit prolonged due to an easterly eq. Rossby wave continuing convection in region 7), but it seems like it may have a weaker signal at that point so influences from things like the SSW on top of the low-frequency state (troughy in the east) would lead so something like this.

I'll ask him about it tomorrow. The tool hes using is his own lowpass filter, which he's mentioned is only one of many metrics to refer to, identifying the base state, from which higher-frequency signals like the MJO superimpose on top of when they're stronger. He has been serious about the RMM forecasts lately though. We go over the recent runs at the beginning of each class.

Thanks! This will come in handy