eduggs

All of the mid-range guidance through day 7 has the thermal boundary too far northeast for us to have much of a shot at snow. Out to day 10 isn't much better. I hope it changes. It's a pretty ugly and repetitive looking longwave setup that would seem to favor New England for snow chances. But it doesn't exactly look warm either after Friday and the real cold is not too far off. But it's sure no fun looking at a huge stagnant ridge over the central US.

Cool to see several reports around or even over an inch of snow from yesterday's snow showers in Morris, Warren, and Sussex counties. That made two days in a row of accumulating snow for the higher elevations. https://forecast.weather.gov/product.php?site=NWS&product=PNS&issuedby=PHI This was pretty well modeled.

Right now the best shot at moderate snow accumulations based on a model consensus would be I-95 east in CNJ and maybe into Long Island.

If the GFS is right, some spots might get more snow from tonight's lake effect bands than from the Sat. night event.

The junction of I-287 and I-80 looks like it got into that band pretty good. I bet it dropped a quick 1/2" plus in that area.

For the past few days, meso models and even globals advertised a finger-like lake effect snow band getting into NNJ this evening. And it has verified as advertised. Count me as impressed.

Yet another snowy evening out there. Everything's dusted up pretty good - maybe 1/4". From radar I suspect parts of western or northern Morris county have accumulated 1/2" - 1" this evening. These minor events help soothe the snowstorm deprivation angst.

I have distant memories of short range models fumbling these types of setups, which enhances the tease. But modeling has improved a lot since the 2000s, and especially the 90s. We don't see big, late shifts very often anymore.

FWIW, big improvement on the 18z RRFS vs. 12z... now generally in line with NAM and RGEM.

Yup. But the magnitude of run to run changes is so small at this time range now that it will be really difficult to see big improvements. The range of outcomes has significantly narrowed.

I think it improved early in the run but then shifted east at the end. The ICON did the same.

Noticable shift ESE with the PV on the 18z NAM. Looks more suppressive. Bummer... was really hoping to get lucky with this one and keep trending it. Although it shouldn't be surprising that the outlier solutions shift towards model consensus.

The 12z CMC is the first run I've seen that fully rounds the base in time to spin up the mid/ULL into Nova Scotia. Too late, yes... but closer. The next step would obviously be for it to happen faster and in time to impact EMA instead of Halifax. ... gotta keep pumping heights out ahead of the trof in Ontario/Quebec.

Regarding trend analysis. You should include hypothesis testing and p-values to assess the statistical significance of the trend. Most random scatterplots will show a non-statistically significant linear trend... so you have to analyze if the trend means anything. By visual inspection, the negative trends are largely due to lower-snow years starting in 2015. It could be argued that this down-cycle explains the trend and will be reversed after the next up-cycle. I do believe warmer winter temperatures are affecting seasonal snowfall. But snow is a tricky parameter to analyze and statistical analysis can be very misleading if not presented faithfully.

GEFS mean keeps ticking a little "wetter." NYC just shy of 0.2 liquid now.

Good trends at 12z so far. UK kind of splits the difference between the RGEM and NAM.

It was the opposite - too warm - down in NNJ and SENY yesterday. Showed rain in areas that got accumulating snow.

How far east do snow showers and squalls make it this afternoon I wonder? There could be some training of the lake effect band. Parts of the Poconos will likely pick up an inch or two. NWNJ could get in on the tail end of the action too if we're lucky. Probably not much accumulation east of PA, but flakes are always nice to see.

For the center of this forum's region, as depicted, the 12z NAM would bring warnings snows, the 12z RGEM would bring an advisory, and everything else that's out (ICON, RRFS) would bring sub-advisory light snow/flurries.

The RGEM clearly has less precipitation than the NAM. The RGEM is around 0.3 liquid for the greater metro area with a little more in C/SNJ and a little less in NWNJ and SENY. The NAM is double that... around 0.6 liquid for all of the metro, LI, and NENJ, with less north and south. The NAM (likely overdone) is a great run. The RGEM is a good run. Both were encouraging relative to last night's runs.

The NAM is an outlier right now in the upper levels. It shows a trof structure further west and less positively tilted than everything else. But it also trended better than 6z. It would be very encouraging to see big moves towards this today. The 12z NAM would also feel a lot snowier than what most think of when they see 3-6". That's weekend, daytime snow with cold 925mb temps, near freezing surface, and probable banding. It's a great and unlikely outcome.

I was speculating where I think this is heading, not summarizing what all models are showing. I hope some of the wetter AI model solutions are right. But even they are relatively dry outside of southeastern areas. And they haven't shown a clear positive trend either. The trof is positively tilted and the PV is pretty far east. That's not a great height field orientation to work with... especially as we approach the short range.

I don't think the 0z NAM is much better aloft, if at all, than 18z. The RGEM is a little worse. The GFS and ICON are a little better. Kind of a wash so far for 0z. I think this is heading towards a scraper or light event unless we see clear positive trends very soon.

Some modeling shows possible snow showers or squalls tomorrow. Something to keep an eye on... despite the lack of "snowstorms" so far this year, I've seen snow a lot more to date than the past few years. The vibe feels different.

Turned into a pretty snowy evening for NW burbs especially with some elevation. As already mentioned, the NAM, GFS, and ECM did pretty good along the southern periphery of snow. HRRR and RGEM not so much - too warm. Apart from the ECM and ECM-AI (haven't seen?), 18z wasn't great for this weekend's potential event.