J.Spin

I totally agree. I didn’t know this accumulation was going to be even denser than 10 to 1, but that will be fantastic for the base. We actually were out on the Bolton Valley Backcountry Network yesterday for a snowshoe tour, and I was quite impressed with the off piste/backcountry ski conditions that were already present. The conditions over the past week seem to have been improving under the radar. There was decent base and 6-7” of powder atop that, even down in the 2,000’ – 2,500’ elevation band. On our ascent of the Bryant Trail, I took the image below of a track that a skier had left in the A1A glade area, probably around 2,300’, and I was definitely wishing I’d brought my skis instead. Things have really been primed for a synoptic storm like this, and the coverage is in a position that even the ~0.40” of liquid we’ve picked up so far is actually going to kick things up substantially.

Event totals: 3.3” Snow/0.38” L.E. The overnight accumulations from Winter Storm Izzy already put down quite a shot of L.E. around here – almost 0.40” of L.E. in just this first round. Details from the 8:00 A.M. Waterbury observations: New Snow: 3.3 inches New Liquid: 0.38 inches Snow/Water Ratio: 8.7 Snow Density: 11.5% H2O Temperature: 24.1 F Sky: Snow (1-10 mm flakes) Snow at the stake: 8.5 inches

The Wind Chill Warnings and Wind Chill Advisories that had taken priority on the BTV NWS alerts maps have now expired, so we can see the layout of winter weather alerts in the area for the approaching system, which has been given the name Winter Storm Izzy. The collection of Winter Weather Advisories and Winter Storm Warnings certainly depicts the lower totals expected in parts of NVT and the Champlain Valley, and these can be seen on the latest Storm Total Snowfall Forecast map, which I see mreaves also posted. Here at our site, We’re under a Winter Storm Warning and I’m seeing projected accumulations in the 6-14” range through Tuesday. For the local mountains the projected accumulations top out around the 18-20” range for the highest elevations, and the map does just start to catch a bit of that 12-18” shading along the crest of the spine.

Well, let’s be serious here – does anyone actually think the next two potential weather systems are going to drop 1.5” of L.E. as 100% liquid in the mountains of NNE? The second system in the modeling is a clipper-type system that doesn’t even hint at that possibility, so that’s sort of silly. The point is that the state of the mountain snowpack is such that it could take some rain (only so much before it starts to drain through etc.) as part of the L.E., and it would likely add L.E. to it as part of substantiating the base. Snow and sleet are certainly much better for conditions, and that’s actually all that’s currently shown in the mountain forecasts around here anyway.

Yeah, first there’s this larger system from tomorrow night into Monday to think about, and that could be the synoptic system we’ve needed to get a huge portion of the moderate to steep natural snow terrain in play around here. Most of the models show at least a half inch of liquid equivalent here along the spine of the Northern Greens from that system, although something like the latest GFS run with over an inch of liquid equivalent through Tuesday would be really nice. A shot like that would have a huge impact on the snowpack depths for the natural terrain. As you can see from Matt Parrilla’s Mt. Mansfield Snow Stake Depth Plot below, the snowpack depth at the stake is currently 28”. That’s certainly below the average 40” snowpack depth, but nowhere near the basement as far as seasons go. It’s not 28” of fluff either; it’s substantial, and essentially primed for whatever comes next. The ~24” mark is about where people typically start skiing the natural snow terrain (lower and moderate-angle stuff), and indeed, that’s what I’ve seen at Bolton over the past week or so. I suspect PF and bwt have been seeing similar things at Stowe and Jay. The snowpack reaching the 40” mark at the stake (The Northern Greens 40-inch rule) is where you’ll find most natural snow terrain (even the relatively steep stuff) reaching practical utility. With a current 28” depth at the stake, we are absolutely within striking distance of that 40” mark with a good storm or two, and it’s hard to express what a game changer that would be – trail counts and available acreage would jump dramatically. In some respects, it doesn’t matter whether this next system delivers snow, sleet, freezing rain, or even plain rain; it’s that liquid equivalent that we’ve been lacking because we’ve had a relatively slow trickle of smaller systems over the past couple of weeks without the sprinkling of major or even moderate systems. Obviously, getting all the liquid equivalent as pure rain would be least optimal, but the mountain snowpack is in a robust enough state right now where it would still be substantiated by that liquid equivalent, unless the temperatures were somehow 50 or 60 F. Straight rain isn’t currently what’s forecast, so it’s more likely that any liquid equivalent will come as snow, or some other frozen forms of precipitation. And then indeed, there’s that midweek system. From a quick look at some recent runs of the GFS, I think something in the 0.3” to 0.5” inch of L.E. range is what it’s been showing around here for the spine from that potential midweek system. It’s up and down of course, and we’ll have to see how it changes over the next several days, but we do like the typical reliability of those types of systems: If the mountains ultimately pulled out something on the high end like 1.5” of L.E. from these next couple of systems, it will seriously transform the ski options.

I’ve added the updated season snowfall progression plot for our site below. As you can see from the slope of this year’s cumulative snowfall trace over the past week, we’re toddling along at a reasonably steady pace, but comparing to the average slope, we’re clearly behind average snowfall pace. We’re obviously not going to catch up all in one fell swoop without a real whopper storm, but even a typical 6-12” storm would make a notable dent in catching up, since we’re only 18” behind average pace at the moment.

This prompted me to update my numbers and check, and we’re right around 18” behind average season snowfall pace as of today. We’ve actually had 7-8” in the past week (helped by 3.8” from Winter Storm Garrett last weekend, and 2.4” from this frontal passage), but it’s sort of been a trickle, and not really helping to gain any ground on average pace. I’ll try to put together the updated season snowfall vs. average plot when I get a chance.

That reminds me of my coldest ski day I can remember, because we had a situation almost the opposite. My friend’s radio in his Blazer had not worked in years (he instead just drove around with a boom box on the seat), but it started working on that day, and it appeared to be due to the cold. We always joked that it was simply because we’d finally reached superconducting temperatures, although it was probably something along the lines of cmponents contracting enough in the cold temperatures to reestablish a broken contact. We were skiing at Jay Peak, and the summit air temp was -20 F. I didn’t remember the wind speed, but I know that the net result was -80 F wind chill on the old wind chill chart, so I just looked it up, and that meant the summit winds were in the 30 to 35 MPH range. On the new wind chill chart, it’s only -55 F, but it’s right on the verge of that fuchsia 5 minute frostbite time area. We only took a few runs, and after each one, we’d have to spend 30 to 45 min in the lodge warming up because we both found that our knees were tightening up horribly (maybe due to the fluid getting cold). Now I don’t even think of riding the lifts when the air temperature is below 0 F, and rarely even if it’s in the single digits F. I find it just excruciating to have to sit there on the lift, suspended in the winds without being able to move and generate body heat. It’s just much more comfortable (and obviously safer with respect to the potential for lift malfunction) to skin up a sheltered route out of the winds and be able to quickly turn around if the combination of temperature and wind just doesn’t make sense. As PF noted the other day, the skiing often sucks at those really cold temperatures anyway because of crystal structure and the fact that you’re not able to generate the typical liquid for glide. You can help get around this somewhat with the right cold weather wax I believe, but it can only do so much, and there are just too many factors detracting from the experience on those really cold days to make worth the hassle when, as a local, you have so many opportunities for great days anyway.

Event totals: 2.4” Snow/0.05” L.E. It looks like this afternoon’s snow was the end of the precipitation associated with the cold front and cold air advection – we’re definitely into the cold air now. I discovered that the snow we were getting here at our house was actually because we were just on the eastern edge of this afternoon’s activity - I headed to Burlington, and the snow continued to pick up has I got into the western slopes. At times the visibility dropped substantially, and at one point the snowfall was intense enough that it prompted switching over to headlights and fogs. Once I was through Williston, the snow began to clear up to partly cloudy skies, and the temperature had dropped off well into the teens and single digits. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.2 inches New Liquid: Trace Temperature: 1.9 F Sky: Partly Cloudy Snow at the stake: 6.0 inches

I recently got a text message that BTV NWS has put up a Winter Storm Watch, and I see klw has some text posted. They’ve got that 5-8” for NVT, so certainly in the range of what you’re thinking. I suspect the Wind Chill Warning is superseding the Winter Storm Watch on BTV NWS advisories map, so there’s not really a useful graphic to post for that yet.

I’m still checking on it, but that thread seems to become more of a gripe-fest and less of an analysis session with each passing model run. The tenor has been moving that way for the past couple of days because the weenies are in this quasi-combative state where some have apparently “checked out” or whatever, and others are still hoping for dramatic changes in the track/behavior of the system, or fine with whatever happens. It creates a clash. Hasn’t just about every major model been portraying this potential system as some sort of “inland runner” for days at this point? But, as usual, the analysis in the main thread has been heavily slanted toward figuring out any, in some cases almost inconceivable, convoluted way in which the model output shows some sort of improvement for SNE in terms of wintry weather. If the models had shown a system somewhere around the benchmark for run after run after run like this, we’d probably instead be reading “The models always sniff out the big ones well in advance”, or something along those lines”. I’m not sure I’ve seen that uttered once in there despite how consistent so many runs have been showing this in similar locations – and we’re still days out. In any case, kudos to the folks like Tip and Ginx who noted the signals for a significant event in that Monday timeframe at a long lead, but one wonders if that big lead time just served to get the weenies excited for some sort of perfect winter storm. We still don’t even know exactly how this system will play out because it’s days away.

Event totals: 2.2” Snow/0.05” L.E. From what I can see in the BTV NWS forecast discussion, today’s ongoing snowfall is still associated with the current frontal boundary, so I’ll continue to roll the totals into that event. Details from the 12:00 P.M. Waterbury observations: New Snow: 0.2 inches New Liquid: Trace Temperature: 25.2 F Sky: Light Snow (4-15 mm flakes) Snow at the stake: 6.0 inches

Event totals: 2.0” Snow/0.05” L.E. The heaviest snowfall from this frontal passage was late yesterday evening, but it continued into the overnight to add some additional accumulation. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.7 inches New Liquid: 0.01 inches Snow/Water Ratio: 70.0 Snow Density: 1.4% H2O Temperature: 26.1 F Sky: Light Snow (1-2 mm flakes) Snow at the stake: 6.0 inches

Stowe has a huge area of some of the best green circle-pitched glades you will find anywhere. The whole Sunrise Glades/Birch Glades/Chapel Lane/Lower Toll Road/Chapel Woods area is just acres upon acres of low-angle glades that are typically well maintained and can be skied in very low snow conditions. I know people have already been skiing them this season because I've seen PF post pictures. With the Mt. Mansfield Stake snowpack depth at 27”, and people already skiing glades of similar elevation and pitch (Wilderness Woods/Bear Run Woods) at Bolton, so they really should be skiable now. I’m sure PF has the beta on the conditions there.

It’s really interesting to hear it put this way. I sort of disagree with the first part, insofar as I find just about any mountain that combines relatively steep pitches, high-capacity lifts/skier traffic, and manmade snow, to be a recipe for horrible on-piste conditions. It’s not just Stowe that behaves that way, any high-capacity resort (eastern or western U.S.) suffers on that type of heavily-traveled snowmaking terrain unless it’s refreshed. The tough conditions can definitely be alleviated by natural snow, which makes a dramatic difference between places like Whiteface and Stowe – both of these are mountains with plenty of great, steep terrain, but Stowe getting roughly twice the amount of annual snowfall makes a big difference. The absolute diametrical opposite from the situation above would be Bolton’s Wilderness area, that I just described for jculligan the other day. There you’ve got lower-angle terrain, low capacity lifts or human-powered ascents, and zero snowmaking. That’s a recipe for great conditions, with Wilderness having the added bonus of being entirely above 2,000’, and having some of its lower slopes being very well protected from the wind. Your other point about Stowe being different when the off-piste opens up is appropriate though – that creates an entirely different world. I’ve done the calculations on Stowe’s actual acreage when you can ski everything, and the in-bounds terrain alone is roughly 2,600 acres. With the Hazelton Zone it goes to almost 2,800 acres, and then when the sidecountry (both sides of Mansfield, notch side of Spruce, etc.) is added you’re looking at something in the realm of 3,000 to 4,000 acres of lift-served skiing. They never advertise those numbers of course, but everyone who skis the mountain when the snow/base is good knows how massive/expansive the terrain is, even if they don’t know the exact numbers.

We’ve got a bit of snow starting to fall here at our site, and it may be coming from the WSW flow of moisture that seems to have been building on the local radar.

Event totals: 0.2” Snow/Trace L.E. We picked up another tenth of an inch of snow overnight, which I’m attributing to the same event as yesterday. We’ll see what happens over the course of today and tomorrow, but anything in this upcoming period will likely go into a different event/storm. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 25.5 F Sky: Cloudy Snow at the stake: 5.0 inches

Event totals: 0.1” Snow/Trace L.E. There was the occasional flake falling around midday today when I was outside, but they became a bit more consistent as the afternoon wore on, and I found a tenth of an inch of accumulation at 6:00 P.M. observations time. Reading the BTV NWS forecast discussion, there are a lot of factors mentioned that are currently at play in producing the weather the area is getting, including a stationary boundary dropping south, a weak elongated vorticity lobe in the 700 to 500 mb layer, Lake Ontario/low level moisture, an upper level trough, and embedded shortwaves. Some of those components might be responsible more for what’s taking place off to the north and west of us, so for here I’m going with the descriptor of “Shortwave in upper-level trough with low level/Lake Ontario moisture”. There’s technically a different shortwave associated with tomorrow’s snow potential, and then a cold front tomorrow night, so I’ll have to see if we get anything associated with those and if there are any obvious break points to distinguish them as separate events. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 23.5 F Sky: Light Snow (1-3 mm flakes) Snow at the stake: 5.0 inches

Event totals: 0.3” Snow/0.02” L.E. The snow seems to have cleared out this morning, so I’d say that’s it for this event. The next potential system for the area appears to be in the Thursday/Friday timeframe. 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: -6.3 F Sky: Partly Cloudy Snow at the stake: 5.0 inches

Event totals: 0.1” Snow/Trace L.E. Today we had various periods of light snow, but flakes were small and a tenth of an inch of accumulation with a trace of L.E. was all we picked up. We’ve had a bit more potent snowfall this evening though, and it may be enhanced by a bit of moisture from Lake Champlain based on the comments in the BTV NWS forecast discussion. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 10.0 F Sky: Light Snow (1-3 mm flakes) Snow at the stake: 5.0 inches

We hadn’t had any accumulation earlier, but we have with this streamer that just came down the I-89 corridor. Flakes are small, so it’s just a tenth of an inch, but we’ll see if any other streamers come through in this batch.

It’s been getting cloudier all morning and I’m starting to see some flakes here at our site, so it may be in association with that moisture that the radar shows coming in from the northwest:

Event totals: 0.5” Snow/0.14” L.E. It looks like the overnight accumulation marks the end of this storm, so the totals above should be the final numbers at our site for this one. 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: 13.5 F Sky: Partly Cloudy Snow at the stake: 5.0 inches

The temperature I'm currently seeing here is 33.4 F; I haven’t been following it too closely, but I did see it up around 35 F earlier today.

I was just returning some thawed snowboards outside and the precipitation seems to be mainly snow now in this area. The flakes are small – generally a mm or two.