J.Spin

Event totals: 1.6” Snow/0.09” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 1.6 inches New Liquid: 0.09 inches Snow/Water Ratio: 17.8 Snow Density: 5.6% H2O Temperature: 27.0 F Sky: Light Snow (2 to 5 mm flakes) Snow at the stake: 7.0 inches I wasn’t sure how much snow we were going to get overnight with the start of this next system, but the sound of the plow on our road early this morning suggested it was off to a quick start. We actually picked up more snow in just the first round of this storm than the entirety of the previous one.

Event totals: 1.5” Snow/0.05” L.E. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.1 inches New Liquid: Trace Temperature: 29.5 F Sky: Cloudy Snow at the stake: 6.0 inches The tail end of the most recent system brought a final tenth of an inch of snow this morning, and that should do it for that event. The next system in the queue is expected to move into the area tonight, with potentially another 1-3” like this last one, although our point forecast does suggest the potential for accumulations of 3-5”.

Snowpack has indeed been on the low side, but it’s been persistent for the most part since what was really an incredibly early start (even besting last season’s very early start by a couple of days at our site). Overall I’ve really been loving this January weather so far though – if there’s a month to have above normal temperatures, this is definitely it. If I was to write up the winter I’d put those below average temperatures in November, March, and April, and above average temperatures in January. We’re getting snow, and we’re not freezing our butts off in artic cold while the storm track gets pushed far to the south. Sometimes you have to deal with some mixed precipitation when the systems come through, but I’ll take that vs. the cold and dry scenario that sometimes happens this time of year. I know some folks prefer the high and dry scenario more, since it’s great for snow (and ice) preservation, but the snowpack is really too meager to really be going there yet. We definitely need to get more liquid equivalent into it, and if that comes with some mixed precipitation I’d still argue it’s still going to be better than high and dry.

Event totals: 1.4” Snow/0.05” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.3 inches New Liquid: 0.01 inches Snow/Water Ratio: 30.0 Snow Density: 3.3% H2O Temperature: 26.1 F Sky: Cloudy Snow at the stake: 6.0 inches There’s some precipitation pushing into BTV right now on the radar, so we may not be quite done with this event, but we’ll see if anything accumulates in our area: The next system in line appears to be an upper level trough/shortwave with an arctic front that could bring some snow squalls tomorrow.

Event totals: 1.1” Snow/0.04” L.E. Details from the 10:00 P.M. Waterbury observations: New Snow: 0.2 inches New Liquid: Trace Temperature: 20.6 F Sky: Cloudy Snow at the stake: 6.0 inches

Cool stuff PF, and indeed that 24-hour period had a couple of super fluffy measurements that were sub-0.005” of liquid and thus got rounded down to zero. That of course pushed the net ratio for that stretch up to 45 to 1, even though the main measured sample came in at 27.5 to 1. Of the three rounds of measurements I had during that period, the 0.04” reported actually came with the 1.1” of snow at 12:00 P.M. on the 5th. The subsequent two rounds of measurement (0.3” of snow at 6:00 P.M. on the 5th, and then 0.4” of snow at 6:00 A.M. on the 6th) came in with 0.0007” and 0.0035” of liquid, respectively. The second one didn’t miss the 0.005” by much, but ultimately they both got rounded down to 0.00” of liquid. For the most part it should average out over the course of a season, but sometimes you’ll get those days where samples just miss the threshold and get rounded down to zero. The rounding is probably for the better in some respects. For example, the 0.0007” of liquid was probably low anyway – I get to the scale as quickly as I can, but in these small samples, evaporation/sublimation is having an effect. If you leave a core on the scale for a minute or two inside, you can see the mass of the sample decrease as water is lost. It was certainly some of the driest snow I’ve seen this season though – you could simply wave your hand past the snowboard and make it fly away if you wanted to.

Event totals: 0.9” Snow/0.04” L.E. Details from the 4:00 P.M. Waterbury observations: New Snow: 0.9 inches New Liquid: 0.04 inches Snow/Water Ratio: 22.5 Snow Density: 4.4% H2O Temperature: 25.0 F Sky: Mostly Cloudy Snow at the stake: 6.5 inches

It was just cloudy at home in Waterbury, but I’m approaching the Burlington area and they’ve got some light to moderate snowfall occurring.

Event totals: 4.3” Snow/0.31” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.4 inches New Liquid: Trace Temperature: 12.6 F Sky: Mostly Cloudy Snow at the stake: 5.5 inches We picked up a final round of super dry snow last night, and that should mark the end of Winter Storm Henry. The next system in line is quickly moving into the area though, with snow expected to start later this morning and roughly 1-3” of accumulation expected down at our elevation and more at elevation: Area Forecast Discussion National Weather Service Burlington VT 639 AM EST Mon Jan 6 2020 .NEAR TERM /THROUGH TUESDAY/... As of 320 AM EST Monday...Cloud cover is overspreading the North Country this morning in advance of an occluded front. This front is expected to bring snowfall to much of the region with northern New York and the spine of the Green Mountains expected to see decent snow accumulations through Tuesday morning. Models continue to remaining good agreement with snow totals generally 2-4 inches across northern New York, 1-3 inches across Vermont and 3-6 inches across the higher summits of the Green Mountains.

Event totals: 3.9” Snow/0.31” L.E. Details from the 6:00 P.M. Waterbury observations: New Snow: 0.3 inches New Liquid: Trace Temperature: 20.7 F Sky: Flurries Snow at the stake: 6.0 inches The snowfall had tapered off quite a bit and it looked like this would be the last round of accumulation for this event, but it’s picked back up this evening so there will be at least a bit more to report.

Event totals: 3.6” Snow/0.31” L.E. Details from the 12:00 P.M. Waterbury observations: New Snow: 1.1 inches New Liquid: 0.04 inches Snow/Water Ratio: 27.5 Snow Density: 3.6% H2O Temperature: 28.2 F Sky: Flurries Snow at the stake: 6.0 inches

Indeed it’s often real, and perfectly normal, but as Alex said, the 60+ made this round of trolling a bit over the top.

Yeah, I’ve noticed that as well; it’s like some sort of defense mechanism for when potential warmth is on the horizon or something like that. The “Rains to Maines” thing appears to be in the same vein. OK, so CT’s winter climate isn’t that great, but constantly trying to schadenfreude the rest of the region into it at this point, when they all know the shtick (Alex, now you know) is pretty much like hanging a “Desperate” sign around one’s neck.

Yeah, there’s some nice efficient production of flakes and you can really see it banking up against the spine: We’ve had about another inch or so here at the house, and it’s stacking up nicely with minimal wind, so I’m sure the next analysis will come in with a pretty high snow to water ratio. Wind was picking up in more exposed areas when we were in town though, and the Vista Quad is currently on wind hold up at Bolton Valley.

Event totals: 2.5” Snow/0.27” L.E. Details from the 6:00 A.M. Waterbury observations: New Snow: 0.6 inches New Liquid: 0.03 inches Snow/Water Ratio: 20.0 Snow Density: 5.0% H2O Temperature: 26.4 F Sky: Light Snow (1 to 8 mm flakes) Snow at the stake: 5.0 inches

Event totals: 1.9” Snow/0.24” L.E. Details from the 10:00 P.M. Waterbury observations: New Snow: 0.9 inches New Liquid: 0.07 inches Snow/Water Ratio: 12.9 Snow Density: 7.8% H2O Temperature: 30.6 F Sky: Light Snow (1 to 4 mm flakes) Snow at the stake: 5.0 inches

Event totals: 1.0” Snow/0.17” L.E. Details from the 4:00 P.M. Waterbury observations: New Snow: 1.0 inches New Liquid: 0.17 inches Snow/Water Ratio: 5.9 Snow Density: 17.0% H2O Temperature: 33.3 F Sky: Light Snow (3 to 20 mm flakes) Snow at the stake: 4.5 inches

Snow started up here in the Waterbury area around 10:00 A.M. – it’s still fairly light at this point, but I’m seeing some of those larger flakes you mentioned and we’re starting to get a bit of accumulation down here at 500’.

I’m not sure why I even looked, but yeah, you can’t help but love the sentiment in the “main storm thread” as Winter Weather Advisories go into effect.

We’ve got a Winter Weather Advisory posted now for incoming Winter Storm Henry. Our point forecast here suggests 3-8” through Sunday with some additional potential accumulations Sunday night into Monday.

With the improvement in conditions thanks to these past couple of storms, we hit the mountain for a bit of skiing around New Year’s, so I’ll pass along some Bolton Valley conditions and pics. The additional snow that came on the 1st is when the resort really starting opening up natural snow terrain. On Tuesday, snowpack in mid to upper elevations offered about 4 inches of powder atop a thicker layer/crust, and then there was another roughly 4 inches of dense snow below that, and then you got to the base snow. By Wednesday that topmost layer of powder was generally 6 inches plus, so the powder skiing off piste was definitely improving. There’s still not enough snow to open more than moderately-pitched natural snow terrain, but another storm or two without any major warm storms will obviously get terrain expansion going. There is a decent amount of natural snow terrain that’s set for powder skiing and should be great with additional accumulations:

Yeah, we are actually behind on seasonal snowfall at our site as I mentioned above. Mean is ~55” and we’re at ~50”, so of course we’re well within 1 S.D. of the mean and not behind the eight ball, but a shot of snow would at least help keep pace with average. And LOL at the thread for this potential storm – of course now it’s a POS storm. I still find it really weird how people “track” the storm through the model runs and somehow project the feeling that the end result is “changing” as the output from the models changes. Using terms like “losing the storm”, or “it’s gone” really perpetuates this. The reality is that the end result was always going to be what it ends up being – the model runs were simply suggesting something that wasn’t ever going to occur. If model runs show nothing and then a modest event pops up out of nowhere, the weenies are positive as if it’s some sort of “win”, but if there are model runs showing a potential larger event that ends up smaller, or as nothing, then it’s doom and gloom and whatever effects ensue due to the nonsense they built up in their heads.

December Totals Accumulating Storms: 11 Snowfall: 30.0” Liquid Equivalent: 3.02” 2019 Precipitation: 61.49” December snowfall came in right at 30.0 inches, which is definitely lean with average being closer to 40 inches. Thanks to these last couple of storms at the end of the month though, snowfall did end up better than the 25.1 inches from last season. December can be a very impressive snow month here with moisture of the lakes still in play, and that potential January arctic cold and storm suppression not typically in the picture yet. But with this December in the books now, it’s been a surprisingly long time since we’ve had a strong one with respect to snowfall – looking at my data it’s been since the 2012-2013 season, which had 49.5 inches of snow. The 11 accumulation storms this month was right about average, but total liquid equivalent was a couple inches on the lean side, and snowpack was well below average, so it’s really going to go down as a pretty lackluster month. I haven’t summed SDD for the snowpack, but I’m sure it’s quite low. Although we’ve maintained snow since the pack began back on November 8th, it’s limped along at just an inch or two during the middle of the month. Mean snowpack right now is close to a foot, so we’re still several inches below that, and it’s only been the past week that’s it’s really started to increase again. November was a bit above average on snowfall, but with December being slow, it’s not surprising that we’re a little behind average pace on the season. Mean snowfall to this point is ~55” and we’re at ~50”, so it’s lagging a little, but it’s not really a huge deficit at this point.

Nobody loves hard data more than me, so I think it’s awesome when people post these to speak to the “model X is better than model Y” weenie-ness. However, there are at least a couple of points that people never really seem to drive home sufficiently for me: 1) How does model performance with respect to 500 hPa correlation (which I’m assuming is analyzed globally for the 20° – 80° N region in these data sets?) actually relate to the model’s effectiveness as a guidance tool for sensible weather at the surface? Beyond that of course, how much utility is there in that analysis for the model’s region-specific performance for a certain part of the globe? 2) So you’ve already got the above factors in play, and then, how are you going to convince me that a couple of hundredths of a difference in correlation coefficient is even relevant? The trend in model difference (and actually a bit of correlation improvement) is clear over the course of those years, and with so much data, the stats may be there to support a statistical difference between the anomaly correlation of the two models. Regardless of that outcome though, it still doesn’t speak to the relevance of a 0.03 difference in correlation coefficient to the actual utility of the models. Again, I love when people post these types of data, but I’d like to hear more about whether or not they actually speak to a realistic difference in model performance that matters to forecasting.

I’ve seen various people on the boards get confused on this, and it’s because there’s not necessarily any correlation between a system’s resolution (what’s the smallest level of detail that can be discerned), accuracy (how close are you to reality/expected value) and precision/variability (reproducibility). I don’t follow the specifics of weather modeling, but from what I’ve seen (and this can be the case in other systems as well) there’s typically an inverse correlation between resolution and variability. Some types of output from the ensembles are sort of an example of this with smoothing/low resolution. Low resolution output will likely be less susceptible to variability in some cases because you’re not even going to see changes below a certain threshold.