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Spring 2019 New England Banter and Disco


HoarfrostHubb
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25 minutes ago, It's Always Sunny said:

I read that in several cases it outperformed the Euro for tropical systems in regards to model forecast error so I'm expecting good things with it. Here is one article I read that highlights a lot of new features: https://www.weather.gov/media/notification/scn19-40gfs_v15_1.pdf

Very interesting! Thanks for sharing. 

2 minutes ago, dendrite said:

More gridpoints for wizzy to point and click as the error approaches the limit of infinity.

:weenie: 

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Hm .. the former GFS had multiple biases, each one could skew reality in their own right and at times mimick the other bias' ... at other times, offset.  Really frustrating that way... 

For example, the model's progressive bias - it ablates the tops of ridges down too quickly in the mid range.  This has feed backs that cause new errors... for one, ends up increasing confluence over eastern Canada ( just one example in many ...), which then we have overly strong BD/west moving CAD signals...  That is a cold bias result, in a model with a warm boundary layer problem.   Zoink :wacko2:

There's other areas where is seems to contradictory bias its self...  Maybe that fooled the testers/QC evaluators ( ha ha...kidding here)  because between heat wave boundary layers of 114 F at Nashua NH, while given least excuse imaginable to snow in D.C. from a BD cold air mass in July ... you end up with the right temperature for NYC.   Yea ...see?  good model.  

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6 minutes ago, Typhoon Tip said:

Hm .. the former GFS had multiple biases, each one could skew reality in their own right and at times mimick the other bias' ... at other times, offset.  Really frustrating that way... 

For example, the model's progressive bias - it ablates the tops of ridges down too quickly in the mid range.  This has feed backs that cause new errors... for one, ends up increasing confluence over eastern Canada ( just one example in many ...), which then we have overly strong BD/west moving CAD signals...  That is a cold bias result, in a model with a warm boundary layer problem.   Zoink :wacko2:

There's other areas where is seems to contradictory bias its self...  Maybe that fooled the testers/QC evaluators ( ha ha...kidding here)  because between heat wave boundary layers of 114 F at Nashua NH, while given least excuse imaginable to snow in D.C. from a BD cold air mass in July ... you end up with the right temperature for NYC.   Yea ...see?  good model.  

I hope someone is eventually able to get the issues fixed too regarding the NAM being too moist with profiles during the overnight. 

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I see his point though ... 

I had this conversation with Ekster years ago...when the ETA was just becoming the NAM, how the model was kind of like a 'victim of its own success'.  

The problem with immense computing power operating on very small grid spacing ...means you're starting to tap into the uncertainty principle - as a metaphor.  I don't mean really down at the quantum scales.. .but.. .in some ways, something similar happens.  Just apply electrons to a system that 'predicts' based upon very finite inputs for finite scales, you end up with overly emphasized forces and factors that "giga" motion the system into unwanted results - in effect, you open Pandora's box of fractals.   .

Models can't ultimately predict the future? 

That's not really what's happening when the models are fired off...  They are predicting likely outcomes, with ever decreasing probability for success in doing so at that, for every quantum instant of time that elapses further and further into the future. But the actual reality of the future cannot really be ascertained without actually being in the future, because of mercurial nature of ( almost ) unavoidable chaos.  

By the time we get to day fives, we're ...I dunno somewhere in the 40th to 60th percentile for success, and it's dependent upon the 'stability' of the pattern at hand there. 

Day ten?  Forget it... 10 maybe 20% tops.. Which means, by those deeper range time spans the unpredictable, unknowable future circumstances that emerge along the way ( chaos ) have corrupted the futility of models down to guess work, all but entirely.

There is a theoretical limit to that success rate. Models can max out.  We're not there yet.  But techniques, such as ( maybe ) the Euro 4-d normilzation schemes, which are remarkably successful at picking and choosing those spontaneously emergent distractions that need to be  'canceled out', can be applied to models with NAM-like finite grids.  Who knows..just spit-ballin' there.  But there's room to improve ... and all those improvements combined, we'll never get 100% accurate at some theoretical limit, because ultimately ... the uncertainty of chaos cannot be preordained. 

The only way to do so ... as hinted by that parenthetical 'almost' above ... is to control the future.  Science fiction ...for now.  But, if there can be conjured technology that governs the quantum momentum state of every particle that embodies the fluid medium of the atmosphere, sufficiently that it suppresses "butterflies" .. then you don't have to predict the weather: the solution is, push this button if you want a sunny day. But you know what's funny ...?  In a philosophical sense, even in such a fantasy futuristic world, there is uncertainty in a system that 100% capable of modulating the weather.   Because there's no guarantee that the operator won't be influenced by either a foreign agent, or lapse into some sort of psychosis that entices him/her to push typhoon buttons. 

God have mercy on those souls in that realm of existence.   

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5 minutes ago, Typhoon Tip said:

I see his point though ... 

I had this conversation with Ekster years ago...when the ETA was just becoming the NAM, how the model was kind of like a 'victim of its own success'.  

The problem with immense computing power operating on very small grid spacing ...means you're starting to tap into the uncertainty principle - as a metaphor.  I don't mean really down at the quantum scales.. .but.. .in some ways, something similar happens.  Just apply electrons to a system that 'predicts' based upon very finite inputs for finite scales, you end up with overly emphasized forces and factors that "giga" motion the system into unwanted results - in effect, you open Pandora's box of fractals.   .

Models can't ultimately predict the future? 

That's not really what's happening when the models are fired off...  They are predicting likely outcomes, with ever decreasing probability for success in doing so at that, for every quantum instant of time that elapses further and further into the future. But the actual reality of the future cannot really be ascertained without actually being in the future, because of mercurial nature of ( almost ) unavoidable chaos.  

By the time we get to day fives, we're ...I dunno somewhere in the 40th to 60th percentile for success, and it's dependent upon the 'stability' of the pattern at hand there. 

Day ten?  Forget it... 10 maybe 20% tops.. Which means, by those deeper range time spans the unpredictable, unknowable future circumstances that emerge along the way ( chaos ) have corrupted the futility of models down to guess work, all but entirely.

There is a theoretical limit to that success rate. Models can max out.  We're not there yet.  But techniques, such as ( maybe ) the Euro 4-d normilzation schemes, which are remarkably successful at picking and choosing those spontaneously emergent distractions that need to be  'canceled out', can be applied to models with NAM-like finite grids.  Who knows..just spit-ballin' there.  But there's room to improve ... and all those improvements combined, we'll never get 100% accurate at some theoretical limit, because ultimately ... the uncertainty of chaos cannot be preordained. 

The only way to do so ... as hinted by that parenthetical 'almost' above ... is to control the future.  Science fiction ...for now.  But, there can be conjured technology that governs the quantum momentum state of every particular that comprises the fluid medium of the atmosphere, sufficiently that it suppresses "butterflies" .. then you don't have to predict the weather: the solution is, push this button if you want a sunny day. 

God have mercy on those souls in that realm of existence.   

This is a terrific, terrific statement IMO...and extremely underrated. Anyone who views computer forecasts models should have to read this disclaimer prior to proceeding...seriously. This is what separates model huggers from the rest. You need to use experience and knowledge to determine whether the solution has merit...let's say model X keeps showing a snowstorm...but there is a good deal of spread/uncertainty...by analyzing large scale features you *should* be able to gauge that actual probability of that solution verifying and determine whether to toss or if it has merit. 

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Looks like a wet Father's Day incoming. Did some surf casting last night...one schoolie in our group but pretty meh overall. It was chilly earlier in the evening and then the wind switched more W-SW and felt like someone turned on the hair dryer. Love that effect.

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57 minutes ago, Typhoon Tip said:

Anyone along and N of this line is polishing a turd to call this season summer ( so far .. )

image.png.0fdae7cf803a16bb05d701687baf9d08.png

Right from the opening bell Memorial day weekend I'd have called this stretch just about as good as it gets for early summer.  Not sure what folks are looking for...

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3 minutes ago, dryslot said:

30 yrs living here, This is a first, We wet.....

image.png.1b85631af684e71731ba8c18456d5a37.png

lol

Same thing happened to me in 2009. We had so much rain that the puddles in the backyard were becoming semipermanent. We had a patch of tall grass next to one and we saw a male and female mallard taking up residence for a couple of days. I swear I could grow cattails here.

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4 minutes ago, dendrite said:

lol

Same thing happened to me in 2009. We had so much rain that the puddles in the backyard were becoming semipermanent. We had a patch of tall grass next to one and we saw a male and female mallard taking up residence for a couple of days. I swear I could grow cattails here.

Yea, Unreal, What a quagmire back there, You can smell the muck, Tried mowing once and got the tractor stuck a month back, I said forget it until we get dryer weather, Looks like the pond may be back on Thursday for that area, My poor arbors back there are water logged...............:(

image.png.f7ac486cb4a8a01f3ca2a728c5e55a44.png

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On ‎6‎/‎12‎/‎2019 at 10:28 AM, mreaves said:

We were a little worried about that.  I saw a doe in the area later in the evening and assumed she was waiting for people to leave before getting the fawn and the fawn was gone in the morning.

Excellent non-action! 
Wardens and wildlife rehab folks get loads of new-born "faux-orphan" fawns this time of year from people who are unaware of deer behavior.  Mama deer makes the near-scentless little critter(s) lie still while she's our refueling.  Staying clear and checking later is exactly right.

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