Typhoon Tip

It's emerging as transient. Probably a day or two of warm sector, less like a "synoptic heat burst" Which can get pretty darn balmy in a pre diabetic era of CC, heh. But it won't be a 5 days of 68 with two days near 80 like 2017. It's more of a canonical EPO response across the continent. There's a pretty strong -EPO out there, and with the under pinning PNA in negative phase, the concurrence of those two index modes favors initial height falls down stream of the NE Pac/Alaskan region positive hgt anomaly to be the out west, first, version... Eventually the cold loading would spread throughout Canada and dip down in the NP ... prior to then coming east and that's when we get a plausible winter reclaiming a week ... perhaps the 7th thru the 13th estimate? As far as the GHD event in the foreground, the problem with this one can be identified well by the general scope. It is being ejected across the continent straight into a region that is loosing support for it ever being there. The onset of -PNA, is clue as well... the region E is entering a negative interference. It's why the S/W space is weakening as it comes. It's no longer really even identifiable S of NS after exiting the upper m/a in some guidance renditions. But there's a race between conserving, vs how fast it damps out to the point where it's nothing.

Heh ... didn't read back enough on that one. I saw "...down there" and impulsively donkeyed. haha

That makes 1 of us

If the clipper takes the GFS route, I personally doubt 40 on Wed N of the Pike and probably not HFD - PVD. I'm not even sure how to interpret the Euro .. it's almost like it's too strong with a primary to develop a low in CC Bay like the GFS does ...so it snows through 12z in a burst, then goes 37F with west wind that smells like rain but's really just rotted polar air for a few hours.

there's another solution - you could disallow X reposts ... hahaha

Yup… this event’s got some serious resiliency in the runs … It’s sub index at this point but who cares. It won’t be denied GFS still promoting a thaw soon after but it’s real tenuous looking

It’s moving through the proverbial meat grinder with that oppressive jet careening by (N/stream). Unless that alleviates … that’s what it would take But I don’t know if the general wholesale synoptic handling is even right …

Thread that needle…. it’s like we’re coming full circle with this potential Or trying to

This 18z GFS was suggestive out there Somewhat of colder run. Front’s south of prior. Has it parked below with several waves running along it Feb 4 thru 6 … skimpy on QPF but the generalized overview is all that matters at this range. it’s just one run tho. Been meandering that frontal position every run. In a way … icing scenarios are the ultimate needle thread. Unless it’s something truly rare and awesome like 1998 - very large area. This one would be narrow

No idea ... but TX across the snow storm region look to balloon into seasonal change in the first week of Feb. Some of those place that got the snow may be nearing 80

I'll tell you though .. .spring is sprung in the deep south though.

I see a significant transition gate, going through timed for the 2nd. That was originally progged as a potential winter storm, 4 or so days ago, but has since morphed into what looks now like a symbolic, if not turning into a literal, warm front. It appears now as though whatever that is, it's first of all lifting too far NW - that's in conjunction with the SE ridge becoming more robust in recent guidance trends... It's bullying in these operational guidance so fast that the ambient polar boundary is immediately reassigned to the ST Law to IND type axis. It's like in principle it is acting more like a warm front. It goes by, and there's zip cold and a west wind under +6 850 mb ... appears to be a big thaw - or at least significant one. So those days between the 2nd and say the 8th... That could even heat burst if the ridge gets any more dominating. For now, there's some uncertainty about the EPO in that week. The models are trying to reassert really fast - not sure on that.

I'm on the fence with all this

Pensacola Florida has 8.9” of snow since December 1 NYC, 5.8”

Not impossible ... At the moment, not likely. Just not impossible. Right now the GFS is straight down the Pike. There's even a hint at a narrow Miller B thing there - which is probably the model being too sensitive. The Euro's more nucleated with the low while also slightly N with the track. That's as is...but, want to point out that this is a pure N/stream "little critter" ... sometimes they bite. It's hard to know which one's will over-achieve, versus not. Most don't. But once in a blue moon ...heh I remember back in ... 2003 I wanna say. I was working a db job down on the 900 block of comm ave in Boston ( just up from Fenway district), on a cold day in February that was supposed to have some WINDEX in the area. Unremarkable. But by mid afternoon and 11" later in an emergency winter storm warning, that little critter had other intentions. This incredibly heavy frontogen band just snowed 1/8 mi vis for 3 hours ... I was living in Winchester, Ma at that time, which is about 10 mi N of Boston up 93 - when I got home that evening there was about 2.5" So it was very localized. This is where the goods are as of this morning as per the GFS. There's room there for this to be a biter just yet.

Brian ... can you disallow X reposts?

no sorry. I knew folks were going to forget the CMC main operational model showing all those solutions similar to what actually took place, at d5 --> 3, when other guidance were at times not even on the map. RGEM is something else ...

What we just came through, back in last December was actually a bit more extreme on these ensemble canvases than this -

I kind of would be leery of a warm burst in February to be totally honest. Oh my personal druthers would have me lavishing in it - but the analytical version of self would be wondering, because uuuusually? 3 to 5 days after the warm event, the -NAO is sitting over head like a pachydermal circus mishap... and it starts episodically reloading for 5.5 weeks or something, too - That's what happened in 2018... we had a 70s warm burst, then a couple of coastals in March that I personally would rather not have experience. heh.

Yeah, that 12z EPS mean is a pretty significant continuity break comparing to the previous few cycles, which showed a more coherent pattern change. It wasn't exactly a 'warm' pattern it was signaling, but definitely off the cold throttle quite a bit. This particular 12z cycle mean definitely regresses to cold, however.

Conventionality would have it that going from a 'deep freeze' to a 'relative warmup' back to a 'deep freeze' would feature something taking place along the inflections...

You didn't ask me but ... we're 2 gears in the wave #'s away from this being a better snow year, locally. Uh... what? Basically, thees "+PNA" modes are dubious. As I was defining the design for Go Cart whatever his/her name is ... the ridge component of the PNA's have been very persistently westerly biased. The canonical +PNA is not typically a ridge along 120 W. That spatial idiosyncratic distribution is also drawing the EPO numerics down, which it should. But the overlap is rising the PNA, and we think... great! -EPO with +PNA, what can go wrong? Unfortunately, the idiosyncratic devil is that the ridge position skews/offsets the ability for large scale meridian flow structure east of the Rockies across the expanse of the continent. We end up with a nice N flow tendency in the troposphere along the cordillera out there, but then it turns ENE. There's less impetus there after for the stream mechanics to orient into a more curvi-linear trough. That's the physical manifestation of emerging negative wave interference. But here's the 2 gears aspect: If we move the ridge axis say ... 10 degrees of longitude E, that allows the eastern continent curvature to respond, but this is still too far west ( slightly...). Lakes cutters result. That's gear 1. If we then reposition the western ridge another 10 longitude E again, then the trough anchors more over Lakes, which shifts the storm track more toward the east coast. But here's the aspect that skews this idealized position schematic: the compression in the flow. It's a wild card...one that is a result of cold boreal heights associated with season, pressing S into a mid and lower latitude that is ( more than convention would like to admit ) staggering to recede due to attribution. There was probably no real hope of any kind for those model runs over the last month, that phased those deep scary bombs, to ever happen.. Because A, the trough was too flat from the pattern foot, while B, the flow along it so fast that the S stream is too likely to outpace the subsuming N/stream. It was always model bullshit. This thing for GHD ... is tricky as to how it evolves in "this gear"

We have to be careful with this idea of "other side," too. There really is no 'other side.' These domains are inter-correlated (ultimately), which is purely fundamental; its not like there are solid boundaries in the atmosphere, walling off one identity from another, and then these air masses duke it out via storms. Time is where the relationships are better exposed, as "weather" is just the sound of these domain spaces "communicating". Lag correlation becomes very significant. The NAO, for example. If one did not see the lag-relationship with the Pacific circulation modes, it might actually look spontaneous, as though aroused from some fractal into materializing, and then exerting on the flow ...etc. In actuality, the NAO is a semi-static wave function that is a result of dispersion mechanics, down stream of the Pacific's wave emergence and decay ( constructive versus destructive interference..) - this latter aspect is then significantly modulated by the continent of N/A ... You know it's interesting ... when one really sees and understands that, it's actually less accurate to say the NAO correlates to anything storm-wise. Because it was the Pacific all along. The problem is, we don't have the computing power to see how every decimal point in the total wave propagation in space and time, from Japan to Nova Scotia, will exactly drive the NAO biases... If/when the models are ballooning heights within the NAO domain, the cause for that has already taken place - so it's not really ever a good idea to use the NAO as a modulator. It's more of a beacon for where the PNA was.

I do love it ... thanks for demonstrating someone's actually been not ignoring this when I've written about it. lol - seriously though. Any kind of empirical evidence that supports attribution - to which excessive compression in the winters --> higher velocities is a part ... - tends to get swept under the rug, while our brand of denial is this mind game in here of admitting CC but not allowing it to be causal or a part of the actual weather's make up.

PNA distribution is west biased and has been much of the season – predominantly so … just like the NAO can be east or west.. the correlated weather associated with either is different That spaced PNA doesn’t allow the trough over eastern North America to dig as much you get these flat trajectories… But also while all that’s happening there’s a separate phenomenon related to gradient overabundance, whether you’re in a gradient pattern or not The two of those together are like two strikes before the hitter walks up to the plate