J.Spin

Looking at the November monthly snowfall numbers from our data set, we can see where November ’20-‘21 stacks up. Indeed it was a fairly strong November overall, and with back-to-back storms bringing over a foot of new snow on the 1st and 2nd of the month, it got things off to a very early start that kept the cumulative snowfall ahead of average and helped buffer season snowfall through the relatively slow December. One thing that I hadn’t really noticed until putting the data into graphical form was what a solid run of Novembers we’ve had as of late. The past five Novembers have all been essentially at or above average, and that cluster definitely stands out on the plot.

My previous plot provided the average snowfall for each month to allow comparison to the ’20-‘21 totals, but we can also look at a month across the data set to see where ’20-‘21 sits among the distribution of data. October this season was about as average as it gets at our site for snowfall – it fits right in there among the high and low months, and it actually represents the median value for the data set.

That March value must be quite an outlier for a NNE location. March can certainly show a lot more variability in snowfall relative to DJF in my experience, and snowless/nearly snowless versions can happen, but this far north it’s only a certain combination of warmth and/or dryness that can get the month to come in that low. That’s a good topic though; I’ll start looking at the monthly snowfall comparisons in my data set next.

The next look at the ’20-‘21 season snowfall data is by month, with the plot below showing this past season’s monthly snow totals compared to the ’06-’21 averages (white diamonds) in my data set. There weren’t any really outstanding months this season, but November was solid. It was up there among the top five in my data set, although more than 10 inches behind the strong ’18-‘19 November we just had a couple seasons ago. The below average months are quickly evident, and they were December and March. Each was more than 10 inches below the mean snowfall value, and they obviously marked a couple of the major slow periods shown in the cumulative snowfall plot.

On the topic of snowfall for the 2020-2021 winter season, the next look is at cumulative snowfall, giving a sense of the points in the season at our site where it was ahead of, or behind, average pace. The first plot shows actual snowfall numbers (blue) relative to average (white), and the strong start in early November is very evident. That positive departure was gradually lost through the relatively slow December into the middle of January period before it picked back up from mid-January through mid-March. Then the pace of snowfall slowed down again, briefly getting behind average pace in mid-April before finally recovering at the end of the season. The second plot simply shows the deviation from average cumulative snowfall in inches, but more easily lets one view where the seasons was ahead of, or behind, average snowfall pace. That strong start in early November really jumps out here as well. The more dramatic “surprise” that I think this plot shows well is that despite a season with a relatively lackluster tenor, the vast majority of the season in this immediate area was ahead of average pace on snowfall. It’s really just that notable January dip where the pace fell of substantially, and even there it was still less than 10 inches behind average. The fact that two big chunks of the season (November through mid-January, and mid-February through mid-April) were periods where snowfall was simply losing pace vs. average (note the negative slopes in these parts of the plot) probably played into the potentially reduced perception of the season despite still being ahead of average snowfall pace.

Thanks for the data - I put together the graphics for the difference from mean snowfall at our sites by season, and with disparate averages, using percentage to normalize seemed like the best way to facilitate the comparison. As you noted, ’14-‘15 represented a somewhat substantial directional difference, with ’13-‘14 right next to it being a more muted version. And historically during this period of record, that’s really been it for directional differences aside from ‘06-‘07, but that season’s data are so tight to the means that the differences are really inconsequential. The rest of the differences have just been magnitude. The data certain speak to the general NNE trends in seasonal snowfall we often see, with that horrendous ’15-‘16 season being an extreme, but effective, example. The ’15-‘16 season was outrageously poor with respect to snowfall (an almost unbelievable season at more than 2 S.D. below the mean here at our site). I think NNE had some of the largest deviations from average in the region that season, and even within NNE, I think NVT showed some of the largest deviations. The whole season was quite poor region wide with respect to snowfall. ..and then we have the ’20-‘21 season. It’s quite an outlier on the plot that stacks both the directionality and magnitude of difference between our two sites like nothing else in the data set. It’s not at all like ’15-‘16 that had poor snowfall region wide. Weren’t some SNE sites even above average on snowfall for the season? So to see numbers at your site in the realm of ’15-‘16 (which it certainly looks like on the plot) would seem to make the season extremely anomalous. If someone’s got access to it, or knows how to generate it, I think it would be very interesting to see the New England map for snowfall deviation from average for the ’20-‘21 season. It seems that off to the east of here was affected the most, with NH affected somewhat, and then ME affected to an even greater extent? What was it like for northern and eastern ME?

June 1st is generally when I consider the snow season complete here at our site, so I can start finalizing the numbers. Total season snowfall is the main parameter I track, so I’ll start with that. There were certainly some dry spells with respect to total snowfall, but ultimately the season ended up with 160.6” here, which is about average for my period of record. Below I’ve got the plot of how this season’s snowfall compared to the others in my data set, with the mean value for the data shown by the black dashed line.

May Totals Days with new snow: 2 Accumulating Storms: 1 Snowfall: 0.2” Liquid Equivalent: 2.92” SDD: T I’ve put together my snow and liquid numbers for May, and snowfall was typical, but total liquid was two inches shy of the mean. For the calendar year here at our site we’re at 15.05” of total liquid, which is about five inches behind normal pace, so we’re running a bit on the drier side of average.

When I was out in the yard earlier this morning, we started to get a bit of rain, but I hadn’t seen anything notable on the radar earlier. When I checked later it had the look of upslope showers with a northwest flow, which I don’t think we’ve seen here at our site in at least a couple of weeks. It’s still relative mild out there right now, but that flow definitely gives it a bit of an autumnal feel. On a somewhat related note, I see that the BTV NWS has also put out a Frost Advisory here for tonight, so folks in the area might need to cover up if they’ve put any early plants out.

Thanks for the update – I can definitely see that the width of the available snow has contracted some since when I was there on my outing. I had time on Sunday, so I headed back out for a hike and some more turns. Based on what I’d seen on Spruce on my last outing, as well as the views across to Mansfield at that point, I decided it was time to check out something by the Mountain Triple. There’s some easy access snow right down to the base over there, and that fit the time I had. As I walked along past the Triple, I surveyed the snow situation and headed toward Lower Standard, which seemed to have the best coverage. That area makes for a pleasant stroll because it’s generally quite grassy with modest pitches. Somebody had built the shape of a heart out of rocks on the ground near the ropes course, so that was kind of a nice accent to the area. The snow on Lower Standard is definitely more broken up than what it was a week earlier, and there are a couple of gaps near the bottom that are really best walked vs. trying to skip across on your skis. Sunday was the day we had those thunderstorms around, and as usual, there were some great views surrounding the resort and toward the Notch as the peaks worked their magic and forced the clouds around. While I was hiking I started to hear thunder to the east and northeast, off past Spruce Peak and over toward Madonna and Sterling. Eventually I started to see some tendrils of virga over there, and the thunder was becoming more expansive. I was just getting up toward the Crossover elevation, which was about where I was going to stop anyway because the snow petered out there, but the timing seemed good with the thunder building. I started seeing the first visible flashes from lightning just as I was getting back to the car, and the first drops of rain began to fall, so that worked out. I would have stayed around for some lightning photography over toward the Notch, but none if was producing visible bolts, it all seemed to be well up in the clouds or too distant. A few shots from the outing:

We had a few sprinkles here at the house about an hour ago, but the main moisture definitely seems to be off to east as your radar image shows.

I saw your Spruce post and headed up on Sunday for a hike and some skiing when I had time to get out for exercise. I probably wouldn’t have even had Spruce Peak in the mix of top spots to head for turns if I hadn’t seen how much snow was still there, but it was obvious from your report that there was plenty. It’s certainly not continuous top-to-bottom of course, but there’s several hundred verts worth of nice turns with deep base as you showed. The snowpack there is starting to get a bit sun cupped, but it’s nothing that really hurts the experience yet at this point, unless perhaps you were to stray the extreme edges where the snow has taken a bigger hit and there’s been no skier traffic. Even if natural snowpack on Mansfield is still below average for this time of year, I have to think the coverage there on south-facing Spruce had got be at least typical for this far into May. From the view across the resort, I could see that the usual spots like Nosedive and some of those areas around the Mountain Triple still have some decent coverage, so it would be fun to mix it up with something over there next. That Main Street snow has some very deep areas, but it’s just getting a bit too broken up into segments that one eventually has to make the call to go with something with a bit more continuity for efficiency and longer flow of turns on the descent. It is always fun this time of year getting to see which parts of the resort are holding the snow best for those late season turns. It’s different each season depending on the combination of where Mother Nature deposited snow and where the guns were blowing when temperatures were optimal as you noted earlier. A few shots from my Spruce outing:

April Totals Days with new snow: 10 Accumulating Storms: 3 Snowfall: 10.7” Liquid Equivalent: 4.35” SDD: 9.0 I’ve put together my numbers for April, and it actually came in pretty average for most parameters except for SDD, which was roughly an order of magnitude below where it usually is, due to the early warmth in March. The total liquid for this April did end up about a half inch below average, but there was an additional 1.34” that fell on the 30th and gets rolled into the May numbers. That creates a stretch of close to 6” in a month though, which is a decent run of liquid.

The way things have been going recently really is how Mother Nature runs a spring in the mountains of NNE. There are typically interludes of mild weather, but the mountains getting rounds of snow is perfectly normal The actual “warm” season doesn’t start until roughly Memorial Day or, in some years, some point in June if the spring storm pattern lingers a bit longer. That’s why the trees aren’t really leafed out until then, why people don’t plant their gardens until then, etc. Naturally things can be a little earlier in parts of NNE outside the mountain areas and elevations, but banking on real warmth or a warm “season” until Memorial Day or so is not quite in line with the climate around here.

A few images from heading out on yesterday’s ski tour:

This morning I hit the mountain for a ski tour to check out the new snow, so I can pass along some snow observations. The visible snow line here in the Winooski Valley reached down to around 1,000’, but it varied a bit with aspect, so that made for some neat views. Seeing the accumulations on the Bolton Valley Main Base Webcam, I’d planned on a quick tour over in the Wilderness area, but once I was over there out of the wind, I saw that the accumulations were solid enough to warrant a more extended tour into the higher elevations. Temperatures were below freezing from probably 1,000’-1,500’ on up, so the new snow was dense, but dry. There was a notable jump in accumulations just above 2,000’ or so as the profile below shows. Above that though, there wasn’t a lot of increase, so presumably the snow line crashed down to that ~2,000’+ level pretty quickly without spending a lot of time at 3,000’+. Here’s the accumulations profile observed on this morning’s outing: 340’: 0” 500’: 0” 900’: T 1,000’: T 1,200’: 1-2” 1,500’: 2-3” 2,000’: 3-4’ 2,250’: 5-6” 2,500’: ~6” 2,800’: ~6-7” 3,100’: ~7” As mentioned, the snow was dense but dry, so it skied fairly well. On 115 mm fat skis I was typically sinking in a couple of inches, and there was a surfy consistency to the setup that really let you have some fun and smear your powder turns easily if you wanted. The snow provided plenty of cushion for low to low/moderate-angle terrain, and up above 2,800’ or so, old snow and snow bridges were still in place, so that made any water bars less of an issue. There were a few folks out and about in the Village, but out on the mountain itself it was pretty quiet. All I saw was a fox that ran in front of me, and a guy on a fat bike up near the summit. I was surprised to see him up at that point because there was a half foot of snow, and those things are total dogs with respect to climbing, so I’m sure he’d put in plenty of work. There were some packed areas of snow due to resort operations traffic and wind scouring, so I’m guessing he made good use of that. I’ll put together some images from today when I get a chance.

Event totals: 0.1” Snow/2.81” L.E. Snow started to mix into the precipitation last night, but it wasn’t until this morning that it started to accumulate down here in the valley. We’re still above freezing down at this elevation, so we’re just getting transient accumulations at this point. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 34.5 F Sky: Light Snow (1-5 mm flakes) Snow at the stake: Trace

Event totals: 0.1” Snow/0.11” L.E. As the models suggested, some snow moved into the area with the colder temperatures on the back side of the current system. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 32.4 F Sky: Light Snow (1 to 2 mm flakes) Snow at the stake: Trace

Right on point, this latest storm pushed our site past 160” of snow on the season, ensuring at least an average result for that parameter. Your comment follows up what we were saying back at the beginning of March when there were still two months of winter to go. Per our conversation in the thread the other day, winter in the mountains of NNE is generally November through April, with October and May as fringe months, so the annual snowfall averages actually represent snowfall spread out over that six to eight-month period. People can try to shove everything into just a few months if they want, but Mother Nature doesn’t care. Folks will often write off the early and late snows as some sort of “stat padding”, but that doesn’t really make any sense in the context of actual record keeping. It’s not as if the recent skiing during these spring storm cycles has been on some sort of phantom snow that doesn’t actually exist; the only “padding” going on is these dense April snows keeping our skis off the ground.

Since daylight lingers so long into the evening now, I stopped off at Bolton on the way home from work yesterday for a ski tour. I hadn’t had the time to get out on Wednesday, but it kept snowing much of the day on Thursday as well, so this gave me the chance to see how all the snow had accumulated from this most recent April storm. Valley temperatures had edged a bit above freezing in the afternoon, but on the mountain the temperatures were down in the 20s F. Accumulations from this storm went right down to the lowest valleys, and even the broad, low valleys down near sea level like the Champlain Valley had accumulations that stuck around. At the base of the Bolton Valley Access Road at ~340’ there were a couple inches of accumulation, and naturally, the depths just went up from there. The wind had kicked up by yesterday afternoon on the back side of the system, and that really pushed the snow around a lot, but using the typical calmer, unaffected spots, here’s the accumulations profile I observed on yesterday’s outing: 340’: 2” 500’: 2-3” 1,000’: 3-4” 1,500’: 5-6” 2,000’: 8-10” 2,500’: 10-12” 3,000’: ~12” The snow from this storm was certainly not as dense as what last week’s storm delivered, but the initial accumulations were certainly substantial enough to set up a good base, and then in typical Northern Greens style, the upslope came in after to boost the depth and polish things off. Overall, the snow put down by this storm cycle was right side up, just as PF noted in his post. We picked up rough ¾” of liquid equivalent at our site, and I’d say they’d had at least 1” of liquid in the snow on the mountain. So, while not the 2”+ of liquid that some areas saw in the last storm, this snow offered plenty of substance for solid turns on most terrain, and it was easily bottomless on moderate-angle pitches. There was also still some snow left from the previous storm in spots, so that bolstered things up a bit. Anyway, turns were great with the right-side-up deposition, with midwinter consistency all the way down to the Village areas at ~2,000’ yesterday afternoon. I didn’t tour down to 1,500’, but even there at the base of Timberline the snow was still powder as of early evening. A few shots from yesterday’s tour:

Event totals: 8.4” Snow/0.76” L.E. We’ve had some additional snow showers this evening, but the above totals should be it for this storm unless the activity picks up. Details from the 6:00 P.M. Waterbury observations: New Snow: 1.6 inches New Liquid: 0.10 inches Snow/Water Ratio: 16.0 Snow Density: 6.3% H2O Temperature: 34.9 F Sky: Cloudy Snow at the stake: 4.0 inches

Yeah, I just checked our webcam and I see that snowfall has been picking up at our site as well.

There seemed to be a bit of a lull in the snowfall this morning because we even had a few peeks of blue sky at our site, but perhaps there will be a fourth round today as the ULL comes through. Some models certainly show a resurgence in the snowfall this afternoon: Area Forecast Discussion National Weather Service Burlington VT 758 AM EDT Thu Apr 22 2021 NEAR TERM /THROUGH FRIDAY/... As of 740 AM EDT Thursday...Snow showers will continue through much of the day today as upper level low pushes across the region. Will also have strong gusty northwesterly winds due to increased pressure gradient as low which brought rain and snow to the region yesterday continues to make its way northeastward from Northern Maine into the Canadian Maritimes. There’s certainly still moisture pushing in on the radar with that classic NW look:

Event totals: 6.8” Snow/0.66” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 2.2 inches New Liquid: 0.07 inches Snow/Water Ratio: 31.4 Snow Density: 3.2% H2O Temperature: 28.2 F Sky: Flurries Snow at the stake: 5.0 inches