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December 9, 2017 - Storm Discussion (Breaking the seal on the season for many)

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this fascinating ..  sort of ..

The NAM is fiddling with the spatial orientation between the 06z and subsequent 12z run ...where the latter came in with the more south trajectory of the n-stream part of the ...presumed eventual phasing, about 100 km west in the dive. 

That's significant.. It's kind of like imparting a .01% deviation of an asteroid trajectory when it's still half the distance to Mars ...so that by the time it gets here, it misses the planet by 10,000 narrowly...hugely appreciated miles.   

Same thing in a lot of ways...  those spatial relationships between features up stream will dictate ultimately how that N-stream and S-stream interact more or less successfully in a phase dance along and/or off the EC out in time.  12z version is more conducive - has a more meridional trajectory straight S over Chicago (~) as opposed to mid state Michigan or Detroit in previous examples...  I mean, either would have interaction of streams within the NAM realm of choices there...but this 12z offers more opportunity to "lift"/veer the steering flow out ahead, and more proficiently/cyclonically rotated the features around a common axis.  

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1 minute ago, Typhoon Tip said:

this fascinating ..  sort of ..

The NAM is fiddling with the spatial orientation between the 06z and subsequent 12z run ...where the latter came in with the decent trajectory of the n-stream part of that ...presumed eventual phasing, about 100 km west in the dive. 

That's significant.. It's kind of like imparting a .01% deviation of an asteroid trajectory when it's still half the distance to Mars ...so that by the time it gets here, it misses the planet by 10,000 narrowly...hugely appreciated miles.   

Same thing in a lot of ways...  those spatial relationships between features up stream will dictate ultimately how that N-stream and S-stream interact more or less successfully in a phase dance along and/or off the EC out in time.  12z version is more conducive - has a more meridional trajectory straight S over Chicago (~) as opposed to mid state Michigan or Detroit in previous examples...  I mean, either would have interaction of streams within the NAM realm of choices there...but this 12z offers more opportunity to "lift"/veer the steering flow out ahead, and more proficiently/cyclonically rotated the features around a common axis.  

But it's the NAM and it's only wednesday...still thanks for pointing important focal points

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4 minutes ago, Typhoon Tip said:

this fascinating ..  sort of ..

The NAM is fiddling with the spatial orientation between the 06z and subsequent 12z run ...where the latter came in with the more south trajectory of the n-stream part of the ...presumed eventual phasing, about 100 km west in the dive. 

That's significant.. It's kind of like imparting a .01% deviation of an asteroid trajectory when it's still half the distance to Mars ...so that by the time it gets here, it misses the planet by 10,000 narrowly...hugely appreciated miles.   

Same thing in a lot of ways...  those spatial relationships between features up stream will dictate ultimately how that N-stream and S-stream interact more or less successfully in a phase dance along and/or off the EC out in time.  12z version is more conducive - has a more meridional trajectory straight S over Chicago (~) as opposed to mid state Michigan or Detroit in previous examples...  I mean, either would have interaction of streams within the NAM realm of choices there...but this 12z offers more opportunity to "lift"/veer the steering flow out ahead, and more proficiently/cyclonically rotated the features around a common axis.  

Interesting similarities between NAM and CMC at 0Z on Sunday....almost identical look to them.

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There is actually one other idiosyncrasy between the 00z and 12z delta(NAM).  The 00z NAM was sped up about 200 km or so in the n-stream trough position by the 84 hour compared to this 72 hour position in this 12z run.  Also, the s-stream trough is a little more robust in this version too... 

In total these are good for storm enthusiasts ... this allows the southerns stream cylcogenesis to get it's act together and have those critical mechanics/jet structures already in place for when the n-stream [potentially] latches on. 

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Ah... it's all fun and stuff...  

I know we've spent some effort here citing various NAM coups over the years to offer some sort of rationalism to our hopes and dreams ...but, in reality, any sentence that includes the term "NAM" with concepts beyond 30 or so hours is inherently risking lucidity -  ...that's the nice way of putting it.  

You know ... while we're at it... how many times has the following happened: we're planning for some big dawg, and then some innocuous thing goes ballistic when no one's expecting ... then... the big dawn comes in far less or even non-existent. The atmospheric equivalent of the old "bate and switch"  ha ha ha. 

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1 hour ago, Baroclinic Zone said:

If the upstream ridge is pumped up higher it may allow the downstream kicker to slow.  Also if the ridging is sharper it may allow the kicker to be further w than currently modeled.  If you loop the N American 500mb images on TT you can see you the ridge out west gets beat down and it also shifts E as  we get closer to the weekend.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=namer&pkg=z500_vort&runtime=2017120606&fh=0

+1 for that response.

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Just now, alex said:

Did NH put in a special request to have that tongue of 2.5-5? 

Opiates are efficient cloud condensation nuclei.

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2 minutes ago, dryslot said:

Hmm, I'm on that site.

 

Just now, Ginx snewx said:

Brian where is that on MC

You two need to shake off the preseason rust. You have to manually edit the image URLs. We did that a lot last year. ;)

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Big hit on GGEM...prob pretty widespread low end warning criteria storm for most east of VT...and outside far SE MA/Cape where BL issues are present. Looks almost like a paste bomb for BOS area verbatim.

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Just now, dendrite said:

 

You two need to shake off the preseason rust. You have to manually edit the image URLs. We did that a lot last year. ;)

I changed the URL to 084 and nothing changes instead of 048

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1 minute ago, dendrite said:

 

You two need to shake off the preseason rust. You have to manually edit the image URLs. We did that a lot last year. ;)

i tried bro, which url, throw me a bone I am old

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