SnowenOutThere

The view after the 18z Euro

Yep. I personally just focused on the NS and SW interaction as that's where my pay grade is (and without that going right we don't have a storm) but you're right. It was a major concession on pretty much every feature.

Whos ready for the biggest long range NAM hallucination run of the winter!

What the fuck. I was doing homework the last hour and played the 18z euro and my jaw dropped. It did the thing where it elongates the NS like the GFS. In my opinion it made an absolutely massive shift at the H5. It just failed to really capture the SW wave and get it as far west. While I think that is still a pie in the sky dream it just went from impossible to "extremely improbable".

Hey it can always be a teaching tool of the perfect H5 setup!

I'm not smart enough to identify the causes of the H5 differences I've pointed out but I imagine its some initial dance of our NS around the one centered further east in Canada.

Surface low is 2mb higher and shifted maybe 20ish miles eastward. Honestly, I expected a large cave but here we are.

Coastal redeveloping at hour 75.

Out to hour 57 and if I had to hazard a guess it may be slightly shifted north east with where the heaviest snow fall but will be the same general idea.

It'll be a hold for all practical H5 purposes in overcoming the first hurdle of the interaction of the NS and SW. TBD if everything else also holds or shifts around.

It should still be good - or at least close to good.

Through hour 27 and it hasn't completely caved to the Euro out west, though arguably may be a bit less stretched out (eg worse)

I'll offer my input from what I outlined a few pages ago with the NS H5 lobe. Just know saying "its worse" or "it seems the same" may not directly translate to the surface outcome as all of this is very delicate. Even if the coastal fails the IVT could still snow on us.

Time to assemble the crew.

To show what I mean we gotta watch how the vort dropping out of Canada interacts with the vort coming out of the SW. Lets take the GFS as an example of our two important players. In my opinion these are the main things we need to watch to see if anything close to the GFS will happen. Vorticity lobe 1 is the main factor IMO, so lets focus on that in comparison to the Euro This is merely at hour 36 but we can also see the seeds for why the Euro sucks. The NS lobe is angled worse, and the SW is being chopped in half by the NS and not phased. Now lets run this forward By hour 51 the writing is on the wall Night and day difference with the NS handling. The GFS stretches it out and begins positively interacting with the vorticity of player 2 (our SW); meanwhile, the Euro balls up the NS and lets the SW go it alone. This results in it being unable to capture our surface low latter. By the 72 hour mark the differences which began within a day and a half come to roost. The GFS has one consolidated system with the NS stretched lobe helping amplify the SW energy and the Euro instead has two separate vort maxes. Since this initial deviation is now within a day and a half I expect it to be resolved by 18z tonight... where the GFS probably gives a half cave to the Euro.

NAM will be solidly in the EURO camp. Differences occur by hour 36 between GFS and Euro

Will point out for those interested in seeing snow Sunday we got two pretty good options. Firstly, there’ll be a good upslope on the WV ridges. Secondly, most models agree Shenandoah will be able to squeeze out some accumulations even if the coastal misses.

What is the mechanism behind storms which are able to throw moisture hundreds of miles back west even when weaker and then storms like this that can barely reach a hundred miles with their precipitation?

This is a run where I'm saving all the charts for future use to show people how H5, jet streaks, and temp advection results in surface depictiom

What would the surface conditions even look like? Just dumping dendrites akin to lake effect snowfall?

Man I don't think I've ever seen a temperature advection show something like this. Beautiful depiction of how low pressure impacts the area around them. I mean its amazing.

Don't think the CMC will be as good as it's 0z run.