MDScienceTeacher

Thx! I am glad I didn’t change my trip.

How much would you say you have? I’m in LA right now and I just got a video for my son in Ellicott city and it honestly just looks like 2 1/2 inches and he says it’s sleeting already. I am awfully skeptical of all these six and 7 inch abs.

Disaster

Talking about this one? WB 18Z EURO If this is the entire storm then and this pans out.. this would be a bust.

It actually makes sense. the ai models are just glorified analogue forecast. the both use advanced ML techniques to train on a enormous data sets. Both models are probably trained on more or less the same data and probably use similar techniques

I want @Ji to chime in on this one as he is the SME on this topic. If I had to guess (especially given the major rug pulls over the last 10 years) almost all of them were lost in 72-120 range.

@Ji do you have any historical data on when we usually see a major shift in the global models that typically lead to a fundamental change in snowfall forecast for our region? 48-72 hr range? 72-120 hr range? 120-200 hr range?

Sleet is possible in any of these big storms. The warm layer can find its way in.. but the cold air is pretty well entrenched with this system and and I am not quite seeing much of the negative tilt in upper levels that would lead to warm air intrusion. This is also the same reason why we are not seeing the HECs level QPF totals like we saw in 03. Obviously this can change.. but this looks more like snow than anything else for the DC metro region.

what happened today?

I’m not sold on the PDII comparison quite yet because the QPF progs aren't showing that level of saturation. During PDII, we saw persistent mesoscale banding with radar returns so intense they would have prompted flash flood warnings in the summer. That setup featured a textbook 'tropical tap' where a deep moisture plume from both the Gulf AND the Atlantic converged. The Water Transport was so off the charts because you had a secondary low off the Carolinas acting as a pump, feeding a SSE-to-NNW moisture flux directly into the cold dome. Lift was maximized because that 1040mb Arctic High was so anchored, creating a steep vertical 'ramp' for the moisture to climb. We ended up with 2.5 to 3.5 inches of liquid equivalent (QPF) across the board. Sure we have the 1040 high this time.. but as of now, this current setup looks more like a standard Gulf-dominant system—it lacks that intense Atlantic inflow and the same degree of frontogenesis we saw in '03. It has potential, but the 'firehose' isn't there yet. Could change.. hopefully it does. If I remember, PD2 was a 1 foot deal on the inital warnings.. only after it started training we started to see the 18-24 numbers show up in the warnings.

Not often do you see the Positive Snow depth change end up greater than the total accumulation: I feel like this really accentuates the potential this storm brings with the cold air dynamics/ snow growth.

If @Ji lived in Raleigh he would say “I want 18 to 0 in one run

Pd2 started as a 8-12 event and then as radar started showing moisture training north from off the coast of sc sterling up the totals.. first 12-18 then 18-24 and a lot people around here blew right by the 2 fr mark. it was crazy to see yellow returns training north and it was all snow. Just an epic beat down

Okay I watched so you don't have to. To summarize he says that he thinks he it is gonna cut for no real scientific reason other than probably because he live in the midwest and that “these come northwest typically”. I should have stopped watching when he said that he is a Notredame fan but temporarily he will be an Indiana fan because they are good. Anyways he is probably guessing right and we are gonna get sleet because we suck at snow.

I recommended this site to every one of my former students who showed an interest in meteorology. I often wonder if any of them joined! The way I look at it is that you would learn more listening to people like @psuhoffman , @Terpeast, @Bob Chill and even @Ji than you would learn reading a book or sitting in lecture. Are you planning to go into meteorology? I try to convince both of my boys every day to do it. They track storms on the models too for swell and snow. I just dont know if they have the perseverance to make it through all of the advanced math courses that track requires.

What the GFS is showing right now.. especially how it compares to the Euro and how far our we are and the recent trends seems awfully familiar. I am trying really hard not to be negative.. but we need I swear I have seen this same thing play out like 30 times before. Its almost as if the GFS has a in tendency to over do trends in medium range and then correct back as we move toward game time. I hope I am wrong.. and we finally win one!

On more serious note, does anyone know what teleconnection/ anomaly this is over Bering and how long before it breaks down? I have a trip to California planned for the last week of Jan and I am thinking this will have a direct impact on waves/ swells but it will likely need to break down first. I was hoping to see a big swell event along the coast.

The euro has a nice clipper at hour 348

#BigOnesAreSniffedOutEarly

this is cm right?

We aren’t going to get more snow this year, are we? These models make me so sad.

Jan 2011 too

Yeah I guess. In all honesty I hadn’t seen the euro when I posted this. If I had and saw the favorable trend I probably wouldn’t have posted this. Even at hr 120 we are still in a progressive flow so I guess it makes sense for the ensembles to be in so far apart. In past events we have seen much more agreement but in almost all of those cases we have had a favorable Atlantic.

I mean the individual members couldn’t be further apart

I preferred TT because I though that Pivotal didnt have the slider animation feature.. but I realized just a couple of weeks ago that you can set Pivotal to the slider by choosing animation -> forecast loop at the top of the map.