RU848789

It's been snowing moderately for the last hour or so with an official slushy dusting (0.1") on the colder surfaces now at 34F. Probably another hour of snow looking at the radar. Pretty to watch, as always.

Dry slotted, lol - basically no precip for the last hour here - looks like radar has us getting at least mood flakes soon; temp is 37F. Was 65F at midnight and 59F at 7 am. Edit: we have snowflakes in Metuchen at 37F! Can we get a 1-4-1/2"? Maybe if 1-2 of those heavier bands makes it through here...

Exactly. This wouldn't be more than a moderate 2-4" snowstorm even with cold temps in Jan, as there's just not enough precip and with the elevated surface temps and higher sun angle this one will be unlikely to put down more than 1" on grassy surfaces anywhere. But temps in the 70s and lower 80s yesterday has nothing to do with whether or not we can have a snowstorm the next day. If it turns cold enough and there's enough snowfall intensity, it'll accumulate easily even at midday.

As always, accumulation rate = snowfall rate - melting rate, where based on experience (and some deep knowledge of heat transfer and physical chemistry phase changes) I'd guesstimate the melting rate in mid-March is about 0.2-0.3" per hour during the day (say 10 am to 4 pm) with temps around 32F, so with temps in the mid-30s, I'd expect a melting rate around 0.4-0.5"/hr on the colder surfaces, so we'd need snowfall rates around 0.5"+ per hour (0.05" QPF/hr) to see accumulation and rates just don't look to be that high, which is why I don't expect much accumulation. On the flip side, if we can get a thump of snow for an hour or so with ~1" per hour rates, that can get us ~1/2" of snow on the ground and not everyone realizes this, but once there is snow on the ground, that snow is by definition at 32F (at most), meaning subsequent snowfall is no longer melting at the rates above, which are due to a combination of elevated surface temps and elevated air temps with indirect sunlight - the elevated surface temps are a bigger factor in melting (just look at how much more snow melts as temperature increases with the same insolation level, like we saw over the past couple of weeks after the blizzard) - so I'd expect those melting rates to come down to maybe 0.1-0.2" per hour once there is accumulated snow on the ground. I've never seen anyone truly quantify these melting rates (maybe someone in some research paper has done it?), so these are at best educated guesses - would love to know what they are under various surface temp/surface type/air temp/insolation factor (vs time of day), etc. If I had gotten a PhD in meteorology instead of chemical eng'g, I could see wanting to have done research on such a thing.

At 18Z it's no longer just the GFS showing snow tomorrow, as the AIFS and NAM have a bit and the HRRR is bullish (although it's the long range HRRR which usually is crappy). However, these snowmaps are at 10:1 ratios, which are not going to happen. I'll just be happy to see falling snow, even if it doesn't accumulate with temps in the mid-30s - maybe a bit on grassy surfaces at most, unless temps go a bit lower than forecast. The 12Z Euro also showed an inch or so of snow in the late afternoon - will be interesting to see what the 18Z runs say for those two models. The NWS remains unimpressed (can't blame them), mentioning a change to snow showers, but not predicting any accumulation worth noting (<1/2" for areas at elevation in NWNJ/NEPA/Hudson Valley).

FYI, I was emailing with David Robinson, the NJ State Climatologist about New Brunswick snowfalls and he said that the March 1888 blizzard was 36" (estimated) in NB. Obviously data from that long ago can be a bit iffy, especially with the reported very high winds and drifting, but that's well out of range with what you have for CNJ, like the 21" vs. other much higher reports in NYC. This is one of those storms where a 20-36" swath might be more appropriate.

New Brunswick recorded 36" in Mar-1888 - still have no idea how NYC only measured 21" with those historic pix showing what looked like way more.

Lock It Up...

Thanks! Interesting to know that it only begins in 1951 and some data are missing. Do you have a link to these data? I tried finding it, but to no avail...

Don - do you have access to the winter season severity index specific rankings for cities like NYC and Philly? Both are listed as "extreme" for both cities (and most in the NE), which means top 20% (top 33 or so out of ~165), but I'm curious where this winter ranks exactly. TIA. Also curious how close your scores are to these. chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://journals.ametsoc.org/view/journals/apme/54/8/jamc-d-14-0217.1.pdf

This. For some reason people don't seem to understand that we don't need arctic cold to get major snowfall up through at least early April in these parts. All that's needed is for it to be just cold enough for snow and snowfall intensity that's enough to overcome any melting even at midday. We've seen it happen so many times that it boggles my mind that there are people who say it can't happen - if people want to say it's harder for that to happen after 3/15, sure, that's obvious, but it's nowhere near impossible.

This post didn't age well, like many of your posts around here. Your anti-winter bias clouds your judgment here, just like it does on the Rutgers Rivals football board where we both post about the weather. The only difference there is that it's filled with normies who don't like snow and winter and they love you for downplaying almost every winter threat.

1.4" at 8 am and still snowing...

So we got 1.3" of fine powder overnight with temps in the mid-20, but the temp is now up to 29F. All surfaces covered, including the treated street in front of our house. One more band possibly coming through soon. Love seeing the snowpack refreshed and newly gorgeous again. It just wants to snow this winter, as we got another overperformer.

Looks like 21.3" from 10 am measurement is my final total, bringing me to 53.0" for the season; snow has already compacted to about 18" as of 12:00 pm when I checked after my final shoveling. My number looks good given the actual snowfall map below which has most of the 95 corridor and the coast in the 18-24" swath. T The GFS ruled among all of the models up until the event, but especially several days out latching on to the big phased snowy storm solution when almost every other model was showing a weak, progressive out-to-sea solution, and then I thought the HRRR did quite well with real-time projections once the event started. And great forecast by the NWS, sticking to their guns with the high predictions that many of us thought were too high and it mostly worked out.