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Keep this in mind when looking at Mt. Holly's forecast and snowfall map. Both are only through 7 am Sunday (they only project out 72 hours) and in thier AFD they said, "Given the uncertainty, our latest forecast stuck closely to the NBM," which should mean the 01Z NBM (the AFD came out at 3 am and would've been based on the 01Z NBM) through 7 am Monday, which is the first graphic, which is fairly close to their forecast map.And if they were forecasting for the whole storm, it would've been the 01Z NBM in the 3rd graphic, which is a respectable starting point, IMO, given the still pretty high uncertainty facing them. I'd expect watches to go up at 4 pm, unless we see some unexpected significant model backtracking on snowfall. And there's plenty of room for them to bump totals up should it come to that, looking at their 10% high probability case showing 12-24" - but they also might have the biggest spread from high to low I've ever seen with their 10% low probability case being for <1" for all. Strap in folks.

And the cherry on top might be the AIGFS trend in precip/snow (it's cold enough). And even though I know there's not a lot of love for the AIGFS, the fact that it's arriving at a pretty good snowfall for 95 to the coast, via a totally different model algorithm (AI vs. physics) is encouraging, meaning the GFS solution can't just be some weird data initialization or model physics error. I guess we have to keep tracking, lol.

PTTD (Post-Traumatic Tracking Disorder) Prediction: GFS caves most publicly at 12Z tomorrow, then when nobody is watching at 6Z Saturday all the models jump to the GFS blizzard solution, then everyone celebrates - for about 12 hours - when the NAM sends us all an FU goodbye, by showing that that blizzard is going to become a snow to sleet to rainfest and all the models slowly follow. 2" of snow, then 2" of sleet then 1" of rain to wash it all away. Curtain comes up, NAM bows and waves goodbye.

TWC just had a great set of visuals/animation for both the GFS and Euro runs and also demonstrating what's "steering" all of this, i.e., the big upper level low/trough moving south from Alaska towards off of Seattle, which drives the upper level ridge in the Rockies which drives the upper level trough in the eastern US which our eventual surface low rides along, showing how if the trough is too "flat" the storm heads way SE of the benchmark and we get a whiff or not much (Euro), while if the trough is sharper/deeper it drives that surface low NE-ward towards the benchmark and we get a bomb (GFS). As one might expect, without enough data (and conflicting data) on all of these features (especially that Gulf of Alaska low), the TWC is predicting a bit of a blend of the GFS/Euro, leaning more towards the Euro, but still giving some heavy snow for the coast and less inland, somewhat like the Euro-AIFS, with maybe 3-5" for 95/NW and 5-8" SE of 95 to the coast. Will try to post the video, but for now, here's the pic of their thoughts for the storm: it's not a formal forecast, but their purple is usually 5-8" and dark blue is usually 3-5". It's not a bad "forecast" IMO.

It's an outlier within that group, but it belongs in that group relative to the other 3, as it's much closer to the CMC/AIFS on track and having at least significant snowfall, especially at the coast.

Model Mayhem continues. So, at 0Z, the Euro/UK/ICON all have the surface low move ENE from Cape Hatteras with very robust precip fields (with snow on the NW side of those fields) that are just too far SE to do much for people who live on land, while the GFS/CMC/AIFS/Weathernext2 have surface lows that move ENE from about Norfolk, 100+ miles N or Hatteras, with robust precip fields which are close enough to land to put down a lot of snow at the coast and lesser amounts as one goes inland. Which camp do I believe? No idea, but I will say that the fact that the 0Z Euro ensemble mean is well NW of the Op Euro tells me that the Op Euro has a decent chance of being a bit of a SE outlier and that it should move NW and show more snow. If that were the case, that would tip the balance towards a snowier solution, IMO, since right now, the two best models (Euro-AIFS and Euro-Op) are in different camps.

Bad call. Major improvement vs. 12Z, both in surface low being over 100 miles NW and actually getting 1-3" along 95 and 3-4" towards the NJ coast, vs nada at 12Z. Looks similar to 6Z which people were gushing over.

Like this...

Looks like the 6Z Euro may have been the harbinger for the 12Z comeback. Let's hope the AIFS/Euro look better, like the GFS/CMC/UK do.

No, see my post above - 200 mile NW shift with minor snow for 95 and moderate snow for the coast.

Nice bump in the EPS mean, also...

Not so fast my friend as Lee Corso used to say, as the Euro jumps back NW quite a ways....

Not the bomb from 24 hrs ago, but nice improvement on the AIFS from 0Z. Maybe we can still get a moderate snowfall from this...

So much for the myth that the AI models don't make big moves inside 5 days, lol. The cave to the Euro is nearly complete now.

In case anyone is interested in my summary posted elsewhere, here you go. Well, Dr. No, the King, looks like he might be back, as most of the global models tonight at 0Z caved to the Euro depiction over the last several runs of a much more progressive, flatter storm much further to our SE. So, the chances of a major snowstorm have gone down substantially, but not to zero, and the chances of even a minor to moderate storm have gone down significantly. The AI models, which have done quite well in the 4-6 day range this winter, still show a moderate to significant storm (with only one model the AIGFS still showing a major snowstorm)., while all of the physics-based models show either no snow or only a few inches. The cries you heard last night were from all the snow lovers around the world, lol. Below is a summary of the 12Z to 0Z changes... The ICON went from a 12-18" monster for all to nada for everyone (1-2" for AC to Cape May). That's nuts. The GFS went from 6-12+" for everyone at 12Z to 2-5" for most at 0Z CMC went from an 18-24" monster for everyone at 12Z to <1" for everyone at 0Z. Also nuts. The UK went from 8-14" for everyone at 12Z to ~1" along 95 and a few inches for the coast at 0Z. More nuts. The Euro had little to no snow for everyone at both 12Z and 0Z. Dr. No. The AIGFS went from 12-18" for everyone at 12Z to 6-12" for everyone (the high end at the coast) at 0Z. The Euro-AIFS went from 6-12" for everyone at 12Z to 2-3" for 95/3-5" coast at 0Z. The Weathernext 2 went from 8-14" for everyone at 12Z to 2-3" for 95/3-5" coast at 0Z.

Been out all day playing disc golf and just got back and did a quick check of the models and the GFS, UK, CMC, AIFS, AIGFS, Weathernext2, and ICON all showed a major to even historic snowstorm for pretty much the entire Philly-NJ-NYC area (and down to DC and up to Boston in most), but the Euro shows essentially nada. Do I have that right? So, who's in charge of fixing the Euro. C'mon, you guys are meteorologists, make it happen. :>)

I've never seen anything like it. 8 straight runs of the AIFS showing a significant to major+ snowstorm 6+ days out. I feel like we might be watching the meteorological equivalent of Dimaggio's 56-game hitting streak, lol.

Pretty view of the pond across the street from us, as the fairly wet snow clung nicely to the trees, although some was knocked off by the wind. Also, as an fyi, I measured again, just to check compression, and I now have 1.25" on the existing snow vs. 1.5" about 4 hours ago when the snow was over, so I had about 17% compaction, which is fairly typical in my experience. It certainly wasn't melting, as the sun just came up and it's 29F now vs. 31F at 3:30 am. Always being awake and measuring the snow right at the end, when that's in the middle of the night is certainly the main reason I often have slightly higher numbers than those near me who wait until morning.

As of 3:30 am, the storm is about over with very light snow now falling (it fell longer than I thought it would looking at the radar) and 1.5" of new snow on the ground, which is well within the 1-3" range I thought we'd have, but a little below the 2.1" I predicted. It's now down to 31.0F. We could eke out another 0.1" or so if we get some additional light bands to come through as often happens after one thinks a storm is over, but I need some sleep, lol. 1.5" brings our seasonal snowfall to 31.2", which is 2+" more than our 30-year average for snowfall in a whole season.

As of 3:30 am, the storm is about over with very light snow now falling (it fell longer than I thought it would looking at the radar) and 1.5" of new snow on the ground, which is well within the 1-3" range I thought we'd have, but a little below the 2.1" I predicted. It's now down to 31.0F. We could eke out another 0.1" or so if we get some additional light bands to come through as often happens after one thinks a storm is over, but I need some sleep, lol. 1.5" brings our seasonal snowfall to 31.2", which is 2+" more than our 30-year average for snowfall in a whole season

Nice, a little more than the 1.3" I have in Metuchen - hoping to make it to 1.5".

As of 2:00 am, we have 1.3" of new snow and it's 31.5F, so everything continues to accumulate on all surfaces. Snowfall intensity is lighter so might not get much more. Roads will be slippery until temps go back up above 32F around 8-9 am for most S of 78.

As of 1:00 am, still snowing moderately, with 1.1" of new snow on top of the existing snow, so we had 0.4" the past hour, which is our heaviest snow of the event and there's maybe 1/2" on all paved surfaces, even the treated road in front of our house (see pic). Looks like lower intensity precip is close by - not sure for how long. Temp now down to 31.5F.

As of 12:00 am, it's now slightly below 32F (31.8F) and snowing moderately with 0.7" on the ground (on the snow); we have about 0.3-0.4" on other surfaces and a coating on all untreated paved surfaces, so things are getting slick. Radar still looks good for awhile, so I'm thinking 2" is attainable by 4 am when things are supposed to wind down.

This. I'm doing my measurements on top of the hard, crusty snow.