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Don't think we've seen that much pink on an NBM since it started, lol (when did it launch, btw?)

WPC Increased from 50% to 70% to 70%-90% probabilities now.

Why... just because it is cold at the surface... Doesn't mean there will be a warm layer up high.

Siggy

Like the higher heights on the latest run.

Very cool that it's correlating with a good pattern for the 2nd time this Winter

AIGFS shows a complete miss!

Kiss of death. Its coming north.

Does that really say 15 inches of snow for me on the Euro? Wow, this might really be happening. I don't like the freezing rain, especially those totals to the south of me.

I think there is a better chance of it trending south than north.

No, the northern edge of the heavy snow.

I just unpacked my decorative lawn snow measure thingy. I don't dare put it out yet do i?

Quantify "have"....

In Strong ENSO events the PNA usually holds the same state through Dec-Jan-Feb and sometimes March though

Expect a rebuttal from Beavis

Low sat night out here is 12, high Sunday is only 19. DC will be a bit warmer, but I’d expect ratios way above 10. I suppose it’s a safe bet to stick to 10:1 the way things go around here.

Do you mean in terms of big snow -> big rain -> flooding ? Dusted off the account to see what you folks are saying about this big storm. Could be a fun one.

In this case, given the impressive blocking, there is a limit to how far north the system gets. However, mid levels are a different story with strong WAA driven by how strong the low becomes. That’s why you’re seeing surface temps remaining steady or even falling while mid levels keep ticking warmer. As long as the HP is close to what is modeled, plain rain will be an afterthought for most on the board. This is an anomalous cold setup at the surface and the battle looks to be in The mid levels

Yes, you pointed that out way early and it was correct. If I recall correctly, it was strong like, 10/10?

Well, the PNA is a fairly stochastic index, so it probably have something to do with variability.....regardless of ENSO, that index in only going to remain pinned in one direction for so long before it corrects in the other direction. That information, coupled with the tendency for only month to be PNA even during this potent cold phase over the past several years led me to go +PNA this January and call BS when guidance was RNA.

One also saw the same thing following every long duration winter PNA- regime of 25 days or longer. The end of the PNA- regime was followed by a new predominantly positive PNA regime. As for what Larry found, I suspect Arctic amplification is the big driver, as such outcomes were very infrequent prior to 1980.

100%. It is FINE where it is currently, you want it north WHEN THE STORM STARTS (or last run before precip starts) not 4-6 days out. It starts north now and by day 4 you are a cold rain while NYC is basking in 15" of snow.

Latest AFD from Mount Holly- Signals in the upper level pattern by late week and the weekend becomes quite active between the northern and southern stream jets. The key elements embedded in these features are currently located over the Arctic and the Pacific Ocean, so it`ll likely take at least a couple more days for guidance to have a good handle on this system. However, almost all available guidance depicts an area of low pressure developing near Texas Friday before tracking eastward along the Gulf coast into Saturday. Beyond Saturday there still remains forecast uncertainty regarding the details of how this system will play out for the east coast. However, at this time most forecast guidance tracks the low north and east towards the North Carolina coast and then off to the north and east from here by the Sunday into Monday time frame. This track puts the mid Atlantic region on the northern side of the system with the main question then becoming just how close to us does the low track. There will be a very strong and broad arctic high to our north and some of our prior guidance had suggested this may be strong enough to suppress the system just south of the area. But over the past 12 to 24 hours there`s been a general trend northward in guidance suggesting the precipitation shield will make it into our area. In fact, snow probabilities of the NBM now show a 60-70% chance of 2+ inches of snow and a 40-60% chance of 6+ inches of snow for areas roughly along and south of the I-95 corridor with decreasing probabilities farther north. These probabilities are higher than with the prior forecast cycle. So while this system still is about 5 days out, the signal for a winter storm to impact at least parts of the area is higher than usual. The timing of this would be as early as very late day Saturday continuing through Sunday and potentially even lingering into Monday depending on the system`s speed.

Anything is possible at this range. Certainly uncomfortable being in or close to a sweet spot at this point. We will see “trends” and some will over analyze those trends.