J.Spin

I realized that I didn’t even check my site’s snowfall numbers for that holiday stretch, but they were good as one might expect based on what I found in my trip report archives. Here at the house we had 42.8” from the 21st through the 1st, which is essentially like getting a typical midwinter month packed into just a third of a month. If snowfall followed the usual trends, the numbers at the local resorts should have been about double that amount, which would have been a pretty nice daily snowfall average during that period. Holiday skiers and riders surely had lots of smiles.

PF, I checked the archives to see what happened around here ahead of December 21st, 2012 (the point at which we went into a blitz of awesomeness). In October, we actually had five distinct snow events as far as I can tell. The first was on October 8th, the next was on October 11th, and the third one was on October 12th. That third one was the most potent in terms of temperatures, but it still doesn’t look like any of them offered much with respect to turns. I didn’t document the final two events to any great degree, aside from mentioning them in my November 2nd post about the first snow of that month, so the last couple of events must have been pretty marginal. November had at least a couple periods of note. The first was at the beginning of the month, with what looks like accumulations up to around a half foot or so by the 4th. It certainly appears as though the best skiing of the month was right at the end – Mansfield picked up 12-18” on November 30th for some great turns, and then the good skiing carried right over to the 1st of December. Those were actually a great couple of days on the hill: Beyond that though in December 2012, it looks like the fact that you don’t recall anything notable was correct. My December archives don’t have anything of note until the 21st, at which point it was just day after day after day of top notch skiing right into the new year. I had nine outings from the 21st through the 31st, a period that even includes being away a bit for the holiday, so it was definitely an awesome holiday period. Looking at my photos, I see that somehow we even managed some sun in there among all the snow:

A while back, wxeyeNH let me know that my text here in the forum was coming out very small and hard to read on his end – I’m sure it’s a function of the fact that I never type in the forum text editor itself, my material is always written in Microsoft Word files and pasted in. I tried increasing the font in my Word files (from the 10.5 point Arial that seems to suffice on my end in this version of the forum software), but that just made my text large and awkward in the forum (at least when viewed on my devices). I eventually went back to the smaller font, hoping everything had sorted itself out with forum upgrades etc. It still comes out slightly larger than what I assume is the standard forum editor-derived text (see sample in the image below) but it seems at least reasonable. Anyway, wxeyeNH just informed me that it’s still an issue on his end, so I figured we could look into it here in the NNE thread. Are other folks seeing what wxeyeNH is seeing and just dealing with the tiny text, or is it similar to what I see? I’ve added a copy of what my forum text looks like on my end (this is from my Dell PC at 100% scale, but it looks the same on mobile on my iPhone) in the image below so that we can see if we can figure out the issue.

My parents moved down to Florida a few years back, and at first they were there full time, but it wasn’t long before they started coming up here for part of the summer. Now they’ve even bought a second home up here and the period they stay has grown to half the year (roughly May through October). They found that it’s just so hot and humid during the warmer months down there that unless you’re in/at the water, it’s really unpleasant doing most outdoor activities. They’re certainly loving the weather we’ve been having here in the Northeast this summer.

Well, along with these gorgeous days of comfortable temperatures and low humidity that we’ve had as of late, I’ve seen a couple of early signs marking the approach of fall. Right on track last week as August hit, we had the usual first yellow leaves start falling from one of our old butternut trees. And yesterday was the first day that I suddenly noticed the sun angle had a bit of a lower, early-autumn look when I was in my office around midday. That, and the fact that dusk and the first hints of dew were on me much more quickly than I would have liked when mowing the lawn yesterday evening had me curious about the changes in our length of day and sun angle, so I headed to the navy data site: http://aa.usno.navy.mil/data/index.php I found that since midsummer, we’ve lost about an hour and quarter of daylight and 8 degrees off the midday sun angle up here in NVT. Apparently that sun angle change had finally been enough to catch my attention. Coincidentally, tomorrow (August 10th) is the traditional cutoff day where pool use really dropped off around here as noted by the owner of the club where my wife used to lifeguard. We’re well away from the start of school, so I’m sure there’s something about this part of August with respect to a combination of day length, sun angle, temperatures, humidity, or whatever, that hits a threshold up at this latitude. I didn’t really pay too much attention to dates as a kid during the summer, but we spent a lot of our days at the neighborhood pool, and there was definitely that point when you knew prime pool time was done. You sort of had to force it a bit after that, and you quickly realized that there were better things to do. I’m sure sometimes it was as quick as a day that a front came through and the air dried out, but I also distinctly remember hitting that point where you would try to lie out in the sun after swimming, and at its angle it just couldn’t warm you enough for the combination of humidity and air/water temperatures that were available. Thinking back, it was very likely right around this time of year when that change happened, because there was always that period between when you stopped wanting to hit the pool every day and school began. In any event, even if swimming is winding down around here, we’re into one of the best three-month periods of the year for potential “Chamber of Commerce weather”, as PF would say. The graphic below is for The Greater Springfield (IL) Chamber of Commerce, but personally I think it’s got cool potential as a generic icon to use for the concept:

I was also thinking something outrageous, along the lines of… “about average”.

We’re into August, so the July and year-to-date numbers for liquid are below: July liquid: 5.40” 2017 liquid: 37.69” Compared to June, July certainly slowed down on the rainfall, and was it was pretty close to average. Overall though, we’re still running a bit ahead of the game, and continuing with the current pace would put the full 2017 total around 63 inches of liquid.

Yeah, your points on perception are well taken. I’ll typically point out that this past season was the first one with above average snowfall out of the last six for our area in the Northern Greens, but it’s not as if those other five were all horribly below average. The 2011-2012 season was definitely poor according to my data at 76.1% of average snowfall, and clearly 2015-2016 was horrendous at 47.7% of average - is less than 50% of average snowfall even possible around here? The other three seasons, while below average, we more in that 90%-ish of average range, so certainly nothing to complain about. It was really the five year “streak” of not being able to break above average snowfall that was puzzling/spurious, especially when it was certainly not a region-wide phenomenon. Last season’s 123.1% of average did a fantastic job of putting the smack down on that trend… I’d say with plenty of style in that February/March period. The six-year stretch still sits at less than 90% of average snowfall based on my numbers, so we’ve still been in a bit of a rut during the period, but having a season like this last one gives one a bit more faith in Mother Nature reaffirming her averages. Assuming 2010-2011 is part of this decade, I’ve got the 2010’s running at 94.6% of average snowfall around here using my numbers.

Well, the old version of the plot is still showing up here on AmWx for me, but one can use the direct link to the file on my server, and that should present the updated image: http://jandeproductions.com/2017/meandailysnowfall.jpg

I was looking back at the daily snowfall plot during the discussion, and realized that the moving average seemed a bit delayed relative to what I would expect (the midwinter snowfall dip should really be centered around mid to late-January, not early February). I noted that it was because I let Excel calculate the 30-day moving average as an automated trend line, and it plots the average on the last day of the 30-day period. For best visualization of the data, I’d really prefer that it plot the 30-day average on the middle date of the 30-day period, so I calculated the values manually and fixed the trend line. The data are the same, just shifted roughly 15 days earlier. Now the trend line for snowfall ramps up more like I’d expect in November, hits the nadir of the dip around January 20th in line with the individual data points, and the snowfall trend line doesn’t linger so long in April. I updated the plot on my server and flushed the cache there, but I’m not sure how long it would take to propagate to the file visualized here. I inserted a new copy in this post as well to hopefully catch the updated version.

Well, this morning’s precipitation data marks the final entry for June, so I’ve got the June and year-to-date numbers for liquid below: June liquid: 9.43” 2017 liquid: 32.29” Even if it hadn’t been time to report the June precipitation total, I was probably going to send along an observations report at some point today anyway, because there was 2.55” of liquid in the rain gauge this morning. That’s the highest 24-hour precipitation total of the calendar year thus far at my site. Our average June precipitation (7.57”) is already pretty substantial, but today’s addition sent us flying right past that mark to put the month’s rainfall at 25% above average.

Anecdotally, I want to just blame it on the old “too cold to snow” phenomenon, where the storm track gets pushed a bit too far south at the peak of the winter season, and we’re left high and dry up north in the arctic air. I don’t specifically have the data to support that premise, that’s just the way it’s “felt” over the seasons since I’ve been back in NVT. It’s also possible that those cold and dry periods are simply more memorable for me. January is the peak snow month (barely, behind Dec/Feb) and lowest temperature month (barely, behind Feb) for BTV. So, our local first-order station about 20 miles away doesn’t show any January snowfall dip. That’s not to say that the area where I’m located, which exhibits dramatic differences in precipitation, temperatures, upslope snow, etc. from BTV, has to follow suit. But the proximity will no doubt represent some similarities in climate. I don’t personally track temperature data at my site, but I do have precipitation data. January is the driest month of the year in my data, with a 31% drop in liquid relative to the surrounding months of Dec/Feb. There’s also a 16% drop in snowfall here relative to those months. Interestingly, Feb is the driest month in the BTV data. Is the January snowfall dip simply a result of my relatively small data set? Hopefully I can keep the data going and time will tell.

LOL, the degree to which meteorologists not only consider such minutiae but have actually mathematically formalized them, never ceases to amaze me. Anyway, I do have the daily snowfall means for my site, so I figured I’d run the analysis. First off, I thought it would be nice to actually have a visual representation of the daily snowfall means for some perspective on the data, so I plotted that below. As you can see, even after 11 seasons, the daily snowfall means are still quite noisy, so I had Excel add a trend line for a 30-day moving average, which at least gives one an idea of where things might settle in with more data. Although unfortunately contributing to the noise, one fun perk derived from the plot is that individual outliers on the high end are actually products of some of our area’s more memorable storms. The storms associated with the creation of the three highest daily snowfall means are: Valentine’s Day Storm (2007) Winter Storm Stella (2017) Feb 24-25 NNE Secondary Cyclogenesis & Upslope (2012) The origins of the higher points begin to get a bit more muddled after that, but some are still very clearly derived from an individual storm, such as the December 26th-27th, 2012 storm, which wasn’t especially large here (15.5”), but it had an impact on the data because all the snow essentially fell in one calendar day. So to get at the shoulders of the season, at least based on Tip’s definition and my understanding of it, I had Excel perform linear regressions and output the resulting slope for each 30-day segment of the snowfall season. Next, to avoid having to search through all those resulting slopes by eye, I had Excel independently rank the resulting slopes for the first half (generally positive) and second half (generally negative) of the season. Despite the noise in the data, I’d say the results were fairly robust because the dates with the steepest slopes were clearly clustered at two specific locations – the 3 to 5 highest values were sitting right next to each other. So for a visual, the 30-day slope data are plotted below by date according the last day of the segment. I actually took the absolute values of the slopes and plotted those, to remove negative numbers and simplify the plot. So, using those numbers, it would put the 30-day “shoulder periods” of the snowfall season here at Nov 10 – Dec 9 for the fall side and Mar 14 – Apr 12 for the spring side. I was sort of surprised at how much of November is pulled into that shoulder season based on this analysis (vs. the perception of how slowly November snowfall seems to get rolling sometimes), but if going by whole months, it’s clearly got the nod with respect to inclusion over April. April’s still got a decent chunk of itself in the snowfall season though, even down here in the valley, so in line with the thoughts from my previous post, I don’t think it’s too outrageous to throw it into the mix when assessing the winter around here. If the local mountains are being considered in the winter narrative, April really gets a boost in importance as well.

At least here in the Northern Greens, I think it works out fine using November and April as the relevant shoulder months for inclusion in “winter”, for at least a few of reasons. First, there’s the front-end/back-end seasonal symmetry and consistency I see in my snowfall data. November and April snowfall averages here are 10.5” and 6.4” respectively, so November gets a bit of a nod in terms of snowfall, but they both nicely represent similar demarcations from the hefty winter months of December through March with the much more substantial 25”-40” snowfall averages. Of the 22 Novembers or Aprils I have in my data set, only 1 (November 2006) lacked accumulating snow, so there’s a degree of consistency there as well, and it sounds like November is less of a concern here anyway. Additionally, there’s the mountain factor. One can lock their seasonal perspective to a specific observations site for the strictest objective analysis, but for the most part, people’s lifestyles and recreation are intimately linked with the mountains here, so what happens in the middle and high elevations matters in the overall perception of the winter season. If November and April are arguably the shoulders in the valleys, then they definitely qualify in the mountains. Using a whole shoulder month’s snowfall/snowpack data as inclusion in winter assessment may be a bit coarse, but there’s a benefit to having it that way vs. selecting a specific cutoff date. It gives one a free buffer in the assessment for events/stats that may flirt with a more rigorous cutoff. Sure, the first 10 days of November and last 10 days of April may be the least relevant in terms of snowfall or what have you, but for additive elements like snowfall amount, snowpack, days with snow, etc., they generally don’t effect the numbers, so whether they are included or not, it doesn’t matter. For the occasional times when something of importance happens during those periods, they bolster the character of that month a bit, as they should.

I was curious to see how similar things were over here in the Northern Greens, so I checked my data for 2007-2008 and indeed they fit right in with your thoughts. The largest storm here was only 19.2” from 12/3 – 12/6, and we were similar to CAR for the 12/16-12/17 storm with a 16.5” total. Those were actually the top two storms I have in my data, so there was nothing even approaching two feet. The top five storms here that season were: 19.2” (12/3-12/6) 16.5” (12/16-12/17) 16.4” (2/6-2/8) 10.6” (1/1-1/2) 10.2” (3/19-3/21) So it’s easy to see that things quickly fell below a foot once out of the top three storms. But regardless, it was definitely a snowy season. I remember it for having a lot of consistency, right in line with your thoughts as an end-to-ender, and none of the skiers around here would complain in the least if we had another one of those. I bulleted some of the season’s defining parameters in my data: Dearth of massive storms (max 19.2”) Plentiful number of storms (53) Plentiful snowfall to the north (203.2”) Good snowpack (2,518 SDD) Weak shoulder months/condensed snowfall season (150 days) In my annual summary table you can see where 2007-2008 fits within the past decade – the red numbers show it holds the minima with respect to late snowfall start and length of snowfall season, but maxima with respect to snowfall and SDD.