J.Spin

Event totals: 0.5” Snow/0.03” L.E. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.5 inches New Liquid: 0.03 inches Snow/Water Ratio: 16.7 Snow Density: 6.0% H2O Temperature: 29.5 F Sky: Flurries Snow at the stake: 3.5 inches

Snow just started up here at the house with the approach of this next system.

I don’t really know the climate down there, but NOHRSC analysis certainly doesn’t suggest that the local snowpack here is going to disappear because of one mixed system, and I find the NOHRSC projections do a pretty nice job for our site using the CoCoRaHS data. The current snowpack isn’t just a bunch of fluff; even here in the valley it’s been around almost two weeks and it’s seen bolstering and consolidation from six storms. The projected system doesn’t have a ton or rain, and there’s frozen on both ends depending on location. I guess we’ll just have to see how it plays out, but If this was really a big deal, I think people would be talking about issues for the local resorts around here.

Event totals: 0.9” Snow/0.24” L.E. We’ve mostly cleared out, and the radar looks quiet, so I’d say we’re done with this most recent system and the above totals should represent the final values. That was the 10th accumulating storm of the season, with two storms thus far in December and eight from November. That’s a respectable number of storms for November, and it was a decent winter month with fairly average numbers in most snow categories I track. I’m planning to put together the summary for the month with comparison to other Novembers when I get a chance. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.2 inches New Liquid: 0.01 inches Snow/Water Ratio: 20.0 Snow Density: 5.0% H2O Temperature: 24.3 F Sky: Partly Cloudy Snow at the stake: 3.5 inches

Thanks for the update PF – that should be fun to watch. These bread and butter-style events are of course typically way up there in terms of reliability when modeled, relative to many other types of systems, but even then they still have their ups and downs in terms of magnitude. That event went through an interesting period in the modeling where it seemed to weaken a lot, but it has made a resurgence in recent runs. That is definitely one to watch because if it delivers enough L.E., that could set up some low and moderate angle powder turns down to lower elevations than the good snow might be at the moment. This past system has been good for substantiating the base, but it seems like levels for maintaining snow quality were pretty far up there (~3,000’?). This could help freshen up surfaces a bit lower if it delivers enough – it will definitely have a big impact on whether or not I try to head out for natural snow turns this weekend.

Event totals: 0.7” Snow/0.23” L.E. Yesterday’s above-freezing temperatures consolidated the snowpack by a couple of inches, and it did pick up some liquid from the rainy period to create a much more sturdy, base-like consistency compared to what it was like ahead of this system. The snow on the boards this morning was a mixture of granules and graupel, but we’re over to more typical flakes now with a substantial uptick in snowfall intensity when in bands as the radar suggests. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.2 inches New Liquid: 0.02 inches Snow/Water Ratio: 10.0 Snow Density: 10.0% H2O Temperature: 29.5 F Sky: Light Snow (1-2 mm flakes) Snow at the stake: 3.5 inches

Event totals: 0.5” Snow/0.03” L.E. I’m glad I cleared all the boards well last night because we did get some front end snow from this next incoming system. Temperatures were approaching freezing, so the snowpack was starting to get a bit wet as I was leaving this morning. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.5 inches New Liquid: 0.03 inches Snow/Water Ratio: 16.7 Snow Density: 6.0% H2O Temperature: 31.8 F Sky: Cloudy Snow at the stake: 5.5 inches

Event totals: 2.0” Snow/0.14” L.E. Details from the 6:00 P.M. Waterbury observations: New Snow: 1.1 inches New Liquid: 0.10 inches Snow/Water Ratio: 11.0 Snow Density: 9.1% H2O Temperature: 23.7 F Sky: Cloudy Snow at the stake: 5.5 inches

Event totals: 0.9” Snow/0.04” L.E. From what I’ve seen in our area, this morning’s snowfall has been some of the most robust from this system thus far. The flakes were relatively small at observations time, but the size has increased substantially since then. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.5 inches New Liquid: 0.02 inches Snow/Water Ratio: 25.0 Snow Density: 4.0% H2O Temperature: 28.4 F Sky: Light Snow (1-3 mm flakes) Snow at the stake: 5.0 inches

Event totals: 0.7” Snow/0.01” L.E. Today’s earlier event finished up this afternoon, so the above totals should be the final values. Radar suggests the next system is right on the doorstep though, so we’ll see what that one has in store. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.3 inches New Liquid: Trace Temperature: 27.3 F Sky: Cloudy Snow at the stake: 5.0 inches

Event totals: 0.4” Snow/0.01” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.4 inches New Liquid: 0.01 inches Snow/Water Ratio: 40.0 Snow Density: 2.5% H2O Temperature: 18.0 F Sky: Light Snow (2-15 mm flakes) Snow at the stake: 5.0 inches

At observations time this morning I was surprised to find steady light snow falling with some substantial flakes (up to 15 mm diameter), because as far as I knew, our next system in the queue wasn’t supposed to affect the area until later today. I quickly checked the weather models, and even the mesoscale options don’t seem to have picked this up. The BTV NWS thankfully has their thoughts on it in the near term of their most recent AFD, which I’ve added below. As you can see from the radar image, it’s surprisingly robust precipitation for something stealth enough to be missed by even the mesoscale modeling. I’ll call it more than the scattered flurries they have in the AFD text, but perhaps the precipitation has blossomed more in the past couple of hours. Area Forecast Discussion National Weather Service Burlington VT 637 AM EST Tue Nov 30 2021 NEAR TERM /THROUGH WEDNESDAY/... As of 626 AM EST Tuesday...Main change with this update was to expand in both areal and temporal scope scattered flurries for the next few hours. Light returns are showing up on radar across far northeastern NY into northern VT, and area webcams indicate that snow is indeed falling in these locations. However, it does not appear that much, if any, accumulation is occurring with this activity. It`s likely the result of a very weak upper shortwave passing through the northwest flow aloft and should exit to our east a bit later this morning. Otherwise, the forecast is in good shape and no other changes are needed.

Snow present on the ground, or snow actually falling?

Event totals: 0.2” Snow/Trace L.E. We’ve had radar echoes pushing into the area since earlier this afternoon, with flakes here and there, but only in the past couple of hours have we begun to pick up some measurable accumulation. Details from the 12:00 A.M. Waterbury observations: New Snow: 0.2 inches New Liquid: Trace Temperature: 24.4 F Sky: Light Snow (2-4 mm flakes) Snow at the stake: 5.0 inches

I commented on season snowfall and snowpack depth in the previous discussion, but I didn’t mention snowpack start date because I’d been meaning to respond to this discussion. With close to an inch of liquid down from the this past storm, this could easily be the actual start to the winter snowpack for some valley locations. Roughly average temperatures and a typical assortment of storms (even with some rain or mixed precipitation) wouldn’t really knock out a snowpack of this scale, especially since the snow is fairly dense and dry right now, and has the potential to absorb some liquid. Obviously a large enough warm-sector storm could do it, but it would have to be one of those with little to no front side or back side snows. The current snowpack here started back on the 23rd, which would be about a week ahead of average, but the data say that’s well within one S.D. (15 days), so it’s very typical. We’re also very close to the mean start date now anyway (Dec 2). I’d argue the upper mountain snowpack is here to stay at this point based on what I found yesterday at Bolton Valley. There’s already a couple inches of liquid in there, so it would take a highly anomalous system to melt every last bit of that down.

I don’t record temperature stats, but I’d take 20s F and prodigious snowfall all season long over any sort of single digits with respect to “best” wintry weather. I guess cold temperatures are good for snowmaking, forming ice, etc. But also remember that if cold temperatures persist too much in the region, they’re going to cool off the Great Lakes quicker and reduce the potential of that moisture source. In terms of the snow aspect of wintry weather, there really shouldn’t be any fears about this being some sort of anomalous stretch that would be hard to match – the data here say things are proceeding at a very, very… very average pace. Mean season snowfall at our site through today is 13.8 inches, and we’re currently at 13.6 inches on the season. Mean snowpack depth here is 3.3 inches, and we’re at 5.0 inches, so in those respects our pace and recent weather seem quite typical. The usual deterministic caveats apply, but a quick zip through the GFS shows the potential for eight systems in the next couple of weeks, all of which have chances for snow (this is NNE, and we’re heading into December), so it really doesn’t look like we’re simply going to move into a period of benign fall weather.

Earlier I sent along the accumulations profile I encountered today in the Bolton Valley area, and I’ve got a few images below to go with a snow update. As noted, the snow we received around here was generally dense, and it put down a substantial addition to the base on the slopes. We picked up over an inch of liquid at our site in the valley from this storm, and I’d say the slopes of Bolton easily picked that up as well. It feels like there’s at least an inch of L.E. at the base elevations, and probably something like two inches of L.E. up high. Some of the higher elevation snowpack could have come from previous events, but in any case, that’s a substantial amount of L.E. in place. There were a couple inches of drier upslope snow to finish off this storm cycle, but the bulk of it was that denser snow, and that’s definitely what set the tenor of the skiing. There were no concerns about hitting anything under the snow on trails without any overt obstacles like large rocks, and any terrain that was smooth up to the level of single black diamond pitch was fine to ski unless it was wind scoured. In fact, the snow was too dense for skiing any low angle terrain, so you really had to be on moderate to steep terrain or you would be bogged down and just have to straight-line to maintain speed. Skiing on terrain with the right pitch was quite good though, and you could carve right into the powder and just let the skis surf.

Below I’ve got the accumulations profile I found this morning at Bolton. What I found is definitely more than what they’ve got in their snow report, but they did indicate they had trouble with blowing at their stake. It’s possible my measurements were getting down into existing snowpack, but it seems like that should have been consolidated from recent temperatures. The backside upslope snow was also coming down while I was out there today, so that likely added a bit to the totals. 340’: 4” 1,000’: 5” 1,500’: 7” 2,000”: 10-12” 2,500’: 13-14” 3,000’: 14-16”

Event totals: 7.1” Snow/1.09” L.E. This morning’s snow certainly seemed like upslope precipitation, and the radar had that look. The density speaks to its nature, so Coastal got the treble he needed. We’re partly cloudy with some flurries out there now, so if this storm is over, we certainly ended up in the 5-10” range that was in our BTV NWS forecast. There are some echoes building off to the west on the radar, so we’ll see if they have any precipitation that makes it over this way. Details from the 12:00 P.M. Waterbury observations: New Snow: 0.9 inches New Liquid: 0.03 inches Snow/Water Ratio: 30.0 Snow Density: 3.3% H2O Temperature: 27.9 F Sky: Flurries/Partly Cloudy Snow at the stake: 6.0 inches

Event totals: 6.2” Snow/1.06” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 1.2 inches New Liquid: 0.13 inches Snow/Water Ratio: 9.2 Snow Density: 10.8% H2O Temperature: 24.4 F Sky: Light Snow (1-3 mm flakes) Snow at the stake: 5.0 inches

Event totals: 5.0” Snow/0.93” L.E. Details from the 12:00 A.M. Waterbury observations: New Snow: 3.9 inches New Liquid: 0.46 inches Snow/Water Ratio: 8.5 Snow Density: 11.8% H2O Temperature: 29.3 F Sky: Snow (1-5 mm flakes) Snow at the stake: 4.0 inches

There’s definitely some paste love at this stage, and kudos to this system for what it’s put into the base already – data from our site indicates a half inch of L.E. thus far down here in the valley. If this snowfall gradually dries out in typical storm cycle fashion, we know what that means.

Event totals: 1.1” Snow/0.47” L.E. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.6 inches New Liquid: 0.16 inches Snow/Water Ratio: 3.8 Snow Density: 26.7% H2O Temperature: 32.7 F Sky: Snow (1-10 mm flakes) Snow at the stake: 0.5 inches

Yeah, I didn’t get to see it fall, but I just happened to check the snowboards before going to bed and saw the accumulation. I did see a line of echoes on the radar heading off to the east. The snow was dense (16.0% H2O) and didn’t really change the depth of the snow at the stake because I think it just crushed that drier snow down, but this addition is a bit better in terms of the robustness of the base. We’ve had a little mist/sprinkles this morning, but just a trace of additional liquid. Event totals: 0.5” Snow/0.08” L.E. Details from the 12:00 A.M. Waterbury observations: New Snow: 0.5 inches New Liquid: 0.08 inches Snow/Water Ratio: 6.3 Snow Density: 16.0% H2O Temperature: 32.5 F Sky: Cloudy Snow at the stake: 0.5 inches

The BTV NWS has made their update with Winter Storm Warnings along the spine of the Northern Greens as well as Winter Weather Advisories over various sections of the state. They have adjusted the projected accumulations map to include some 18-24” shading in the Bolton Mountain to Mt. Mansfield, and Jay Peak sections of the spine. The Mt. Mansfield point forecast is topping out right around 24”, so that’s consistent with the map. Area Forecast Discussion National Weather Service Burlington VT 341 PM EST Thu Nov 25 2021 .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 340 PM EST Thursday... ...Winter Storm Warnings and Advisories in Effect for Portions of the North Country Friday afternoon Through Mid-day Saturday... Burying the lead, snow totals will vary widely based on location and elevation. In the deeper valleys where no headlines are in effect a generous 1-3" is expected while elevations above 1000 feet outside of the upslope regions will see 2-6". In the upslope regions 4-8" is likely up to 1000 feet with 6-10" further up the slope to 2000 feet with 14-20" likely at the highest elevations of Jay Peak, Mt. Mansfield and Mt. Ellen. Further south along the spine of the Greens 8-12" is likely near the summits such as Mt. Abraham and Killington. Lesser amounts are expected in the Adirondacks, but still a good 8- 12" in the high peaks.