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January 2015 Pattern Discussion


CapturedNature

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I think it's unlikely it takes that long to see something. Models are notoriously bad identifying and timing these shortwaves as they eject out of the west.

I mean the SE ridge coupled with cold in Canada is going to set up a pretty decent baroclinic zone nearby. Doesn't take much of a disturbance to produce precipitation. However if legit threat means big event, that's a little more tricky.

I'll gladly take a couple inches.
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I drafted this up yesterday but didn't post it because ...well, there's some inexplicable results.

 

The MJO wave can be a force in motivating the circulation structure over the Pac and transitively elsewhere, but I further that it is one that is more or less effectual in doing so, based upon whether the in situ wave signature of the wave is IN or OUT of phase with the rest of the domain. When in, the correlation/expectation makes an apparent presentation on the flow structure much more readily then when out.

 

Another way to say: If the WPO and EPO are both negative, the left side of the Wheeler Diagram is in sync.  When these two indices are positive, ...the opposite is true.  

 

Here is the CDC, East Pacific Oscillation teleconnector records to date:

 

post-904-0-88655900-1419701006_thumb.jpg

 

There are some interesting features there (above).  Glaring  ... we can see the EPO negative event that took place back in November, a result of super typhoon Nuri's absorption into the AA phase of the North Pacific. The immediate downstream EPO was a jolt response that rippled downstream over N/A and brought the record early cool snap and GL snows... etc, etc.. But after that collapsed, the EPO has been oscillating through comparatively weaker intervals of both negative and positive.

 

The rub there is that for the first 15 days of December (or so...) both the PNA was positive, and the EPO was negative; the distribution of anomalies over N/A laid down in poor correlation to that. Should have witnessed more cooler results but  ... well, that didn't really happen ... 

 

What I wanted to say is that the MJO "seems" to be in a constructive interference (positive) wrt to the WPO and EPO since some some 17 to 20 days back.  And, here are the composites for NDJ, for the phase 3-6:

 

post-904-0-08422100-1419701482_thumb.jpg

 

That appears a reasonably good fit... But, the monkey wrench going forward is this arctic unleashing.  It seems a bit of anti-correlation will be in play over the N/A domain space. 

 

It all makes me wonder if some corrective event (of sorts..) takes place, much in the same way as Archembault "type" of reasoning (but not specific to her exact regions/scope...).  In other words, putting this arctic air down sort of flies in the face of the longer term correlation for the MJO -- particularly when the MJO is holding hands with the NP, and the two feed-back positively.  Should if anything be even warmer!

 

Notice the D10 operational Euro from 00z last night -- that's not going to happen (if for no other reason just because it is a "day 10 Euro" :) ) of course ...but if it did, that is the sort of look one would expect for an effective MJO passing through Phases 3-6.  Interesting.

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Personally I think the term "pattern" is poorly understood and generally misleading.  I posted my detailed thinking on this topic yesterday and I don't want to rehash and muck up another thread.

 

With cold around and hopefully eventually some stronger baroclinicity, moderate events are definitely possible.  But I also think almost everything is still on the table. 

 

There can be a base pattern or background state of the atmospheric height field that remains more or less in place, while transient shortwaves drive individual storm systems. Poorly understood, sure, but generally misleading, I don't think so. It's not misleading to say that higher than normal heights are going to dominate Alaska in the coming weeks.

 

Then again, why discuss anything here if "almost everything is still on the table." It is a difficult regime to nail down exact tracks in, but people need to realize that the moderate event could occur in Montreal or it could occur in Hartford. The background state being forecast by ensembles supports either solution. Doesn't mean the "pattern" was wrong or poorly forecast. Just poor results for my backyard.

 

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I don't know if there is any significance to this that goes deeper than the mere observation but ...WOW! 

 

I have never seen a geopotential circumvallate (off the SE coast) that exceeds 594 DM at the end of December - even considering the lat-lon. It may not be significant ... who knows, but it does smack as something about what is going on this winter.  

 

gfs_namer_168_500_vort_ht.gif

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Those ready to cancel winter should remember that snowfall in SNE is more closely correlated to precipitation than anything else from about the latitude of Hartford points north, and this December featured plenty of precipitation.

I'm willing to bet that the majority of seasons that started slow in the snowfall department that ended up recovering not only featured above normal precip, but occurred during el Nino seasons.

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The only thing of some concern are the much AN SST's. It may not matter much inland , but that is going to torch BL's if we do get some coastals down the road., for now it seems like the next 2-3 weeks it's strictly clippers and swfe so it won't matter much

I find the warm sst a weak argument. We've all seen cold Nor'easters in very early winter with torched sst. Conversely, remember the 75 with east winds at BOS in march 2012? Upper air contributes more than people realize. Eg: my nightmare of 12/30/00 was mainly thanks to the 850 low coming too close.

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I also think November set a lot of individuals up for a let down (so to speak...). If November was more akin to the rest of the world, folks might be a bit more iron-hauled to the idea of December abandoning their hopes and dreams. Looking over the significant November climate events product, produced by NOAA, the US/Canada region were clearly the exceptions to the rule.   ...Kind of like a cat sticking its head inside a paper bag and thinking that's the world.  

 

The world was warm and wet, however.  Not cold.  The record Lake Effect snows, and a coastal that whitened Thanks Giggedy ... these were local temporal and space anomalies that were more fortuitous to said desires.  Folks should really consider themselves lucky!  Instead, perhaps that N/A antithetical result might have led to disillusioning a few (possibly even rooted back to last winter's unrelenting cold into the MW, into forgetting the state of the world we really live in during the current era).   

 

201411.gif

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Maybe it's the rubber and snapping after a year and a half of chilly?

 

Heh, I don't think it's anything that systemic...  I think just the randomness of on-going positioning of features ...if however transient spread out over time, permitted a 12-16 mo period where EPO's tended to favor N/A for a primary cold conveyor... 

 

As things progress in time... we'll slip away from that.  Who knows what the new paradigm will be.. But given to the predominating "rest of the World reality" that's been going on all the while, it's probably saner to assume warmer over cooler regimes would be favored here eventually.  

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Lol yup. And then it cools right back down after the storm. Plenty of cold on either side of course

 

It's amazing what that model run is doing... It's building and building and building cold while simultaneously engineering ways NOT to allow it modulate the ptype of that event.  Sorry snow lovers... clearly the atmosphere has a major agenda to pump your keesters... Muah ahahahhaha.

 

Seriously though .. I was looking the GGEM and NOGEM (or whatever f they call that frankenmodel...) and thinking, gee, that looks like an icing event.   

 

But, then it also occurs to me that this is all over a week away so there isn't much deterministic value in any guidance type for that matter. 

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This has been the worst winter to this point that I can ever recall.

Jesus.....the rainers interspersed with shots of cold has been uncanny.

I'd rather just an all out blowtorch, like 2006.

Potential between January 5-10, but other than that, we're probably waiting for the 2nd half of January.

Its been pretty bad, I will admit that. I've been pretty busy but am off this week and next. Stepping back looking at this month, i didnt really realize how horrific it has been.

Without blocking, cutters are a given. The million dollar question is if we can get stuff in between. Last year I seemed like we did a decent job at that.

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The NAO is just killing us.

This would have been a great pattern.

 

The NAO is not helping winter's cause ... but it is not the only problem.

 

In fact, the culpability for the alternating rain freeze look is really more attributed to the ridge being too far west/off the W coast. 

 

I wrote extensively about this the other day; that construct in the flow causes the split, where one half curls around the "tuck" UAL in the SW, and the norther component then meanders E across Canada. 

 

The one meandering across southern Canada is confluent in random scales, but enough to support polar high arming from the main anticyclonic node of the NP.  But the SE experiences a ridge, because the flow around the SW UAL is pumping latent heat over those regions.

 

Bottom line, big mess.   Enters the NAO and there's really no way to stop the west/cut scenario thereafter.  So yes, the NAO ain't helpin', but it's really quite possible to cash-in and get good events without it. 

This isn't one of those times.

 

Ryan and I warned people days ago this could (if not likely) happen ... heh, it is what it is.  I have the front door open and love the opportunity to get some fresh air into the home.  So there are thing to covet about this sort thing.  To each his own I suppose. 

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LOL at my meltdowns in here today because of the Euro. I need to get a freaking grip

 

Yes you do ... because no one in here has melted down.  I think you are being more introspective than you are either aware, or are lying - ha!

 

In fact, Jerry and I just had a nice conversation about the warming background climate, and how this may just be a manifestation of that longer term tendency  .. and it was agreeable, interesting, most importantly ...sane.  

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Despite waffles in the op models ensembles are steadfast the past few runs of cutting the system and raining on sne. Euro ensembles have been steady as she goes with this for the past 2 days and today's run is no exception.

It's a classic St Lawrence track which is one of the common winter storm tracks for us when we're on the wrong side.

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