cfbaggett

Oh the irony that the warmest locations this morning may be the snowiest tonight...

So amazing! Hoping for the best for all of us here in Central PA the next 36 hours. Regardless of how it turns out, one has to enjoy the majesty of it all.

This is an eye opener... Days upon days with the possibility of subzero lows...

23 minutes ago, MAG5035 said:

Euro did come inside a bit today vs it’s 0z run, although I think the bigger difference was it was a good bit more expansive on the western side of the snowfall swath. It’s also very sharp with it’s changeover line, mainly snow to light rain and little mixing. Lot’s of time to resolve that track in that situation. I think most of the LSV would still see mostly snow in that scenario, just that it would slot out and since the storm is stacked at the point it’s coming through the Mid Atlantic into SE PA… it won’t be long before the cold air is fully entrained into the system (if it already isn’t). The big thing there is just that the best forcing and deform are further west in PA with the inside track. 

GFS has had a different evolution, more of a straight Miller B type with surface reflection carrying up into the OH Valley, allowing for more of a mixing mess but still actually looked marginally better today with more frozen as there is strong coastal development. Euro has a bit of a jump to the coast in the Deep South but it looks like more of an A evolution. Truly huge differences between that and the Euro are out in the middle of the country. GFS has over 30” of snow at the confluence of the Mississippi and Ohio Rivers where Euro has essentially 0”. 

Wow, I didn't even notice the difference over the OH Valley. And that snowfall is within ~100 hours now for people who don't get much snow! Probably shouldn't post these images in the Central PA forum, but they do, at least for me, help me stay grounded and not worry about individual models or particular runs, even at these relative short ranges.

12Z GFS MSLP operational vs 12Z GEFS MSLP ensemble members. Operational still on the northwestern envelope of the ensemble spread. but maybe not as far NW as the 6Z run.

6 minutes ago, Itstrainingtime said:

Question I'll throw out to anyone more knowledgeable than I am - a subtle change I've noticed since the 12z runs yesterday is an overall slight weakening of the surface low on some of the models. At first, I was disappointed to see that. However, and I know that the overall track matters more, but would a more wound up low also introduce more mixing issues than a weaker low? Or does that not matter at all.

There's not a one-size-fits-all answer to your question. There's also the possibility that the stronger low will allow stronger upward velocities which will cool the column more, allowing more snow. 

6Z GFS operational low location versus GEFS individual ensemble members. Operational is really on the fringe of the spread.

Amazing change in the GFS ensembles in just 24 hours. 6Z yesterday versus 6Z today. Shame this thing is still ~5 days out.

ECMWF 06Z Control Run:

Just a couple of thoughts:

1) I am in awe at the duration of this event. Usually these storms last 9 to 15 hours and done. 48 hours or longer for this one? The end time of this storm is still pretty deep into the model integrations, so there could still be significant error in the models for the second half of the storm.

2) It wouldn't surprise if the heaviest totals end up north and west of currently advertised, as they did significantly with the December storm. First, the models seem to be trending toward tucking the low tighter and tighter into the Delmarva. That makes sense for baroclinic reasons. Second, I have a hypothesis that the models do not advect snow as it falls through the column. It just piles the precipitation up where it falls from the cloud. Assuming the snow falls 1000 m from cloud base at a downward velocity of 1 m/s in a background wind of 20 m/s, the snow could easily be blown 20 km to the west as it falls in the strong easterly winds.

1 hour ago, Atomixwx said:

State College lies in a valley far southeast enough of the great lakes to miss out on Lake Effect snow and far north enough to usually get fringed on nor'easters. It's meteorolical hell. 

The summers are quite pleasant.

1 hour ago, Wentzadelphia said:

Hey all. I’m chasing this storm up from Philly. I don’t want to drive more than 3 hours tops. I was thinking either poconos, but also Williamsport or around the Harrisburg region. Any spots you’d recommend based on current data? I’m a little worried in E PA about the deformation zone lifting farther N than anticipated, but that’d still be better for c pa. Can’t decide! I’d be leaving early  tomorrow morning so still time to get some model runs in.

Lewistown.

And there may be timing differences amongst the members, so some that are east, could have been further west an hour or two earlier. Anyway, it all looks really exciting, regardless.

The green is a mean, median longitude is a tad west.

Subscribed.