weatherwiz

Even some of these shittier OP runs, don't end up terrible. I think the idea of this being an all our hit versus nothing needs to be tossed out. This could still be something that gives at least parts of the region a few inches but I don't think this is becoming a 1-2 feet or shutout type deal.

Hasn't the GFS been doing that at times within a certain time range too? I recall at least a few severe setups in the Plains this past spring/early summer where something like that had an impact on how some of the events ended up performing.

the differences in H5 between the 12z GFS yesterday and today are absolutely insane. The whole evolution of H5 from model-to-model is wild. Hardly any consistency going on. It's way too early to write this off and of course that doesn't set this in stone but these swings in H5 are so large who the hell knows what the "middle" ground is or which side of the field to lean towards

This x100. This is a reason why we probably can't fully discount this until like 12z Thursday, even if things aren't looking so great today and tomorrow.

What a brutal storm that was from a forecasting side of things. Tough pill to swallow on that one

I think this has been mentioned several times but the PAC NW energy and the ridge is a huge factor in all this as well. Not only is there poor agreement with the northern stream energy but there is poor agreement within the PAC NW/western Canada domain. I've also been thinking this but I think this is a situation where ENS aren't going to be much use really. I mean ENS aren't going to tell us what we already don't know and that is a clean/early phase = big storm while no phase = nada or little. Just averaging out (or smoothing when looking at the mean) isn't going to give any insight as to what we can expect from the northern stream energy and the PAC NW ridge.

Yup...told my gf we were definitely getting a foot. ended up with 3.5'' or something

We've had the rug pulled out from under us the last minute before, maybe this can be a rare time it gets put back under us. IT'S COMIG DAMN IT. My bar remains at 24''.

While I have this on my mind... @OceanStWx what is the point of this accumulated Supercell composite parameter energy Index I saw floating around last spring/summer?

Hopefully the last

Throwing it all in on this one, I've made up my mind. Winter for me is this weekend. 24" or bust for me. That's my bar...24". I want to be outside at 1:13 AM EST Sunday morning with my newly purchased yard stick I will be getting this week and sticking it in the snow as deep as I can and when it can't go in anymore...the top of the snow line better be at 24".

Just want to see EPS have some sort of stride towards the GEFS...that's all that would matter right now. Even if it was just a smidge of trend.

Looks like the difference with the northern stream energy become apparent in the 36-42 hour window. So it probably won't be until 0z at the earlies Tuesday night or 12z Wednesday morning that we get a much clearer idea of what guidance has the best general idea with the northern stream energy.

The differences between H5, not only with the northern stream, but the southern stream are absolutely wild but the differences are much more extreme with the northern stream. Must be a sampling difference...have to look at a larger view then just CONUS focused

A far western lean or a tuck right now isn't necessarily a bad thing. We know how this goes...there will be some last minute corrections...I guess as long as those corrections end up being east and not more west But I think the most tucked solutions are probably the envelops as to how tucked this can get. There is more room for east lean versus farther west lean

Weird to say but a part of me doesn't want to see a storm that strong lol. You start introducing some weird, finite and mesoscale processes which can make for forecasting hell.

Agreed. I am internally excited right now but waiting another 24 hours before I get overly excited. Probably better to wait until Wednesday to do that but all the pieces are there...its just about the timing.

IDK if that would be the case this time around, not with a storm that intense. Would probably start farther northwest but collapse quickly towards the northwest side of the center. Scott did just make a good point this would be more of a CCB than a deform and that also may favor something a bit closer to the northwest center of the H7 low, If I'm thinking correctly.

The deform with this would be unbelievable and would probably traverse a huge chunk of the region.

oh baby

150+ knot 500mb jet streak develops as the core of the jet rounds the base across AL/GA...exactly what we want to see. Monster

I wonder that too. I would love to explore model verification scores more and understand the process. I feel like it has to be exceedingly difficult to truly assess model performance and equate that to a particular score because of how complex this is. When you see the graphs comparing model performance at like H5...what is it that explicitly measuring? Is it averaging like observed H5 globally compared to model forecast globally at a particular time? But say one model is handling H5 great overall, but it is weaker in a particular part of the world versus another area where a model with a lower score did better in the area the model with the higher score did...?

If it nails it that will be pretty impressive, but we're going to want to see AI become extremely consistent with nailing storms, otherwise all it is going to do is just add to the uncertainty when there is large model spread. But it also has to go beyond just nailing storms, it needs to be consistent with the evolution of all these features and how the features are interacting. For example, lets say it is OTS because of a lack of phasing and the storm does end up going OTS...well in a sense it was correct with the OTS, however, if there was phasing, just a bit too late which still resulted in an OTS track...well then it was not technically correct. While it had the correct solution, the reasoning was incorrect.

With these type of setups though, its almost irrelevant whether models show a storm or not. Slight tweaks in how the models evolve and interact with the H5 energy can have large impacts on how the sfc evolves. At some point you do want to see models become consistent with showing a storm and favorable track but I don't think that is very important right now...but that time is coming.

I would strongly advise giving the NAM little attention beyond 48 hours for this system with the only attention just comparing evolution of H5 through a 48-hour window....that is all. Beyond that, the NAM will be useless garbage.