Jay Peak Summit: Most Snow in the Lower 48 in 2014-15???

jamesdeluxe":2ynluat7 said:
Admin":2ynluat7 said:
I would be reasonably confident that the base figure is a reasonable approximation for the snowfall throughout the ski area's entire vertical drop.
Admin, are you sticking with this assertion ^^ even though Tony seems comfortable with Jay's 294 inches alongside the other NVT mountains?

Yes. Again, because in a cold winter with little/no rain there's no reasonable explanation for Jay's base snowfall to be only 57% of its summit snowfall. Combine this with the fact that there's no reasonable way to measure snowfall at 3,968' atop Jay Peak, that the base area has the only historical measuring spot, and that the historical average correlation is 80%, and I'm confident that the reported summit snowfall this season has to be a pipe dream.
 
I don't think anyone is arguing against your point that Jay's summit is tough to measure -- and who knows better than someone who patrolled there for a decade -- but at the same time claiming that the entire mountain should be credited with only 214 inches (the base reading) while Stowe and Smuggs got 290 and 294 seems a bit dramatic.
 
jamesdeluxe":4siwq2a3 said:
I don't think anyone is arguing against your point that Jay's summit is tough to measure -- and who knows better than someone who patrolled there for a decade -- but at the same time claiming that the entire mountain should be credited with only 214 inches (the base reading) while Stowe and Smuggs got 290 and 294 seems a bit dramatic.
I never said that.
 
jamesdeluxe":x7dy17oi said:
Admin":x7dy17oi said:
I would be reasonably confident that the base figure is a reasonable approximation for the snowfall throughout the ski area's entire vertical drop.

OK, OK...touché, but that's not what I meant. What I should've said was that while the snowfall may be modestly more than that higher on the hill (which is what I meant by "reasonable approximation"), it's by no means an additional 43%. No way, no how. And the fact of the matter is that no one really knows because no one took reasonable measurements above the base.

I wasn't going to bring this up, but as long as this slogfest is continuing...I can't begin to tell you how many times I'd be on pre-opening patrol work when the radio would crackle with marketing asking the overnight grooming crew how much snow had fallen. If they'd say 6", it would feel more like 4" to me as I was doing trail check. And then the morning snow report would invariably say 10". :lol: That's how imprecise (and unreliable) the process was, at least back in the early 90s. We're not talking here about a snow plot with a white board that was cleaned off at specified intervals throughout the day.
 
Tony asked me to weigh in on this thread since the topic of snow measurement has surfaced. Unfortunately I don’t have any insight into how Jay Peak does their snow measurement in the way we were able to get at it for Mt. Mansfield with Powderfreak. It is somewhat annoying how opaque the snow measurement methodology is at most ski areas, but especially so for Jay Peak since they’ve got this amazing snow magnet of a mountain that seems really worthy of some rigorous snowfall monitoring.

I’m not a huge fan of the lack of snow reporting transparency, but I’m still not sure why everyone gets so bent out of shape about the snowfall reported from Jay Peak. I think that most folks who are familiar with the isolation, location, topography, orographics, latitude, and meteorology of the Jay Peak area can accept that a 10% bump in snowfall at the mountain relative to the other resorts of the Northern Greens farther south isn’t unreasonable. That would put the average upper elevation snowfall in the mid 300” range each season, so I really don’t find their reported overall snowfall average that outlandish. I guess one can sort of “shrug” at the numbers from any given season like this past one when the difference is greater than 10%, but note that the 290” from Stowe is at 3,000’, and the 374” from Jay Peak is presumably closer to 4,000’ up near the peak (more on this below).

Admin":2mtc9fpp said:
Regarding those Jay Peak numbers, I simply don't buy that summit figure. I patrolled there for 10 years. That summit is the rockiest, most windswept place on the planet, save for perhaps the Mt. Washington Observatory. There is absolutely no reasonable way to measure snowfall at that altitude at Jay Peak.

Admin":2mtc9fpp said:
The fact is that Jay's summit is a windswept point of almost solid bedrock right at tree line on an already notoriously windy mountain. Jay officials have a hard enough time keeping any snow there at all, as evidenced by the snow fencing lining the upper Vermonter and Northway trails, the two runs that leave the Sky Haus tram top station. Without that fencing, snow would be blown straight to Canada. Instead, that fencing creates drifts that may be redistributed and groomed by snowcat to cover those two trails. I personally can't imagine how anyone could accurately measure snowfall in that kind of environment.

Tony Crocker":2mtc9fpp said:
What Jay should have done is to place such a device in some upper mountain leeward tree stash, the same technique Jackson and Breckenridge used to bump up their marketing quotes but have the data to back it up. I realize that my use of the term "top of the mountain" set admin off given his personal knowledge of the place. The Jackson and Breck sites aren't top of the mountain either, yet both manage to report 25% more snow that the prior long term mid-mountain sites. That happens to be the long term difference between Jay "upper" and "lower" also.

Like Tony, I think Admin might be taking the “summit” term a bit too literal here. I find it highly unlikely that Jay Peak is trying to measure “summit” snowfall at the true summit of the mountain. Why? Well, first of all, it’s just silly to try to measure snow accumulation accurately in a spot that doesn’t accumulate snow. One has to assume that the resort would have figured this out after decades of operation. Secondly, the resort wouldn’t be getting the sort of summit snowfall numbers they are reporting if they were trying to measure out on a windswept, rocky crag. We see what happens when attempts are made to measure snowfall at such a location – we discussed at length in this forum the depressed snowfall number for the Mt. Mansfield co-op because snow measurements are attempted in this manner. And, as exposed as that area is where the engineers work up on the Mt. Mansfield ridgeline, it’s still a few hundred feet below the true summit and has far more protection than the summit of Jay Peak. The resort has to be measuring snowfall at a strategic leeward site, or sites, near the Jay Peak summit to get the numbers they are reporting, just like Tony mentioned for Jackson Hole and Breckenridge above. Even before Tony mentioned that practice by those resorts, I just assumed it was the case at Jay Peak because it’s the only way they would be able to measure near the summit of that mountain anyway. Now whether they have an actual dedicated high-elevation snow plot like Powderfreak’s 3,000’ setup, or each day’s report is simply a combination of the patrol and/or snowcat drivers measuring in their favorite leeward spot(s) and reporting in, I don’t know. But come on, you know there’s not a guy walking out onto the Jay Peak summit each morning, sticking his ruler down on bare rock and reporting back, “Well, no snow again today!”

Admin":2mtc9fpp said:
Combine that with the fact that it barely rained throughout the entire season, and there is no reasonable explanation for the substantial discrepancy between the base figure and the summit figure. I would be reasonably confident that the base figure is a reasonable approximation for the snowfall throughout the ski area's entire vertical drop.

Admin":2mtc9fpp said:
And with such a cold, rain-free winter, why in the world would there be such a discrepancy between the upper mountain and lower mountain figures? All of this leads me to suspect that the upper mountain snowfall figure is complete fantasy.

You’re pretty familiar with the winter climate here, so the strong assertions above are somewhat puzzling. Yes, the Greens get elevation-dependent snowfall events with a snow line somewhere between ~0’ and 4,000’+ at times (sometimes in midwinter, but more typically early and late season when valley temperatures are more marginal). But by far the most common setup during midwinter is simply snowfall from top to bottom, all the way from the peaks down to the lowest valleys. If the Greens get rain in midwinter, it’s almost always because of a system passing to the west of the area and brining in warm air at relatively high elevations. This is not a recipe for elevation-dependent snow – it’s a recipe for rain at all elevations, top to bottom. So, the occurrence of midwinter rain events in the Greens is not an argument for any sort of elevation-dependent snowfall distribution, nor is a lack of midwinter rain any sort of argument for the absence of elevation-dependent snowfall distribution.

Yes, typical elevation-dependent snowfall with a veritable rain/snow line can absolutely contribute to the greater seasonal accumulations of snow attained at high elevations, but in many places (such as Northern New England, or high-elevation resorts in the Rockies), where storms, especially midwinter ones, are typically snow from top to bottom, that’s not the major cause of snowfall differential at various elevations. The real reason for the difference is that it simply snows more at higher elevations. Higher elevations get more snow regardless of whether or not there is a rain/snow line. The higher elevations are closer to the precipitation-producing moisture, the air there saturates faster, it starts snowing sooner, it snows harder, the air dries out more slowly, and the snowfall lingers longer. These things all add up to more snow with elevation, without any snow line involved.

So Jay Peak reported 374” up near 3,800’ and 214” down around 1,800”. The bulk of this difference is not due to the rain/snow line, it’s simply due to the fact that the summit area gets more snow. Apparently this is a bigger differential than usual based on Tony’s data, but if I had seen those numbers I wouldn’t have given it a second thought. Why? Well, those numbers suggest that 57.2% of the amount of snow that fell at the summit fell at the base, over an elevation difference of ~2,000’. At Stowe, Powderfreak recorded 171” of snowfall at 1,500’ and 290” of snowfall at 3,000’, so 59.0% of the amount of snow that fell at that higher elevation (actually several hundred feet shy of the lift-serviced “summit”) fell at the base, over an elevation difference of ~1,500’. Powderfreak’s rigorously collected data reveal essentially the same ratio of snowfall between high and low elevations as Jay Peak. In fact, with Jay Peak’s elevation difference between the reporting sites apparently being greater, they could easily be showing an even greater snowfall differential between their low and high-elevation sites than they are. I have no idea what the typical snowfall ratio is between the high and low elevations sites at Stowe, but if you use the snowfall ratio that Powderfreak obtained this season and scale for the increased elevation difference of Jay Peak’s reporting sites, Jay Peak would actually be allowed 412” of snow at the summit. If people are going to assert that the base area snowfall of 214” is the “accurately” obtained value, perhaps we should be calling “BS” on Jay Peak’s summit snowfall stat. Maybe we need to complain to them that they have to relocate their upper elevation snow cache because it’s doing a poor job of collecting all the snow that falls and we’re sick of bringing the wrong skis each time we visit. At my house at 500’ in the Winooski Valley, year after year, I get essentially 50% of the snow that falls in the higher elevations of the Bolton Mountain/Mt. Mansfield stretch up above. I recorded 144.7” this season vs. the 290” on Mansfield, and you can’t get much closer to that 50% value than that. Yes, some of that difference came from elevation-dependent snowfall events, but most of it was simply due to the fact that even when it’s all snow from the peaks to the valleys, it just snows more in the higher elevations.

Admin":2mtc9fpp said:
Even in a typical year, there can be a marked difference between the two mountains that are separated by an hour's drive. However, this year many of the big snow events tracked south as coastal storms, evidenced by the record snow that fell in places like Boston. These coastal storms aren't Jay's calling card -- in fact, "Nor'easters" generally deliver bigger snow to places further south along the Green Mountain spine and much closer to the ocean, like Killington. Jay is simply too far from the Atlantic and separated from that giant bathtub by too many mountains. Where Jay excels is on Alberta Clipper-type storms that come in from the northwest. The first mountain of any substantial elevation that those storms hit is Jay, resulting in orographic lift that produces substantial snowfall in a similar way to how Targhee squeezes moisture from storms that roll in through the Snake River Valley of Idaho. It's no coincidence that Jay fans refer to the "Jay Cloud" and Grand Targhee is also known as "Grand Foggy."

After observing and reporting on the weather patterns in the Northern Greens with Powderfreak and the expert meteorologists in the New England Regional Forum at American Weather, I’d say that Admin is spot on here with regard to his Jay Peak climatology. Jay Peak is the most extreme example, but this is essentially the climatology for all of the Northern Greens, and then it tapers a bit as you move into the Central Greens. The Northern Greens can make fantastic amounts of snow out of nor’easters if the storms take the right track that brings them up into the Canadian Maritimes and they stall to form a cut off low, or even if they just pass through the Maritimes on their way out of the area. When low pressure systems are located there in the Canadian Maritimes or northern Maine, the Northern Greens are getting hit with cold, Atlantic moisture-laden air that has wrapped around the top of the storm and comes from the northwest, smashing into the 4,000’ wall of vertical relief that sits to the east of the Champlain Valley. For the Northern Greens, the ideal tracks for nor’easters are through the Cape Cod Canal, or Boston, or similar locations in Southern New England, which will typically put the area in the sweet spot as the storm passes. If a storm tracking like that gets coupled with a stall in northern Maine or the Maritimes, that’s how the mountains can pull in storms with totals in the range of 3 to 5 feet of snow. The thing is, the track of nor’easters is a crapshoot – they can basically pass through the area wherever. If they’re too far south or east, the Northern Greens can simply get flurries, or even just be “smoking cirrus” as they say, and if they’re too far north or west, the area runs the risk of rains. Aside from the orographic “bump” in accumulations that the Northern Greens can get from any storm that stalls appropriately, what really sets the mountains apart from the rest of the Northeast are those Alberta Clipper types of systems that Admin mentions. These are typically moisture starved, but they are quite reliable in terms of occurrence and have almost no potential for rain because they are not strong enough to wrap in warm air. These clippers come across with little fanfare in the region, often track along the international border, and BAM!... they deliver a foot of snow out of nowhere. Those are the events that really set the Northern Greens apart from the rest of the region – they mean more powder days, they keep the snow fresher and of higher quality on the slopes, and they push the snowfall averages into that 300”+ range.

Based on Tony’s snowfall data for the Vermont resorts…

Tony Crocker":2mtc9fpp said:
tseeb":2mtc9fpp said:
Thought some of you might like to see Mustang Powder's summary/farewell/good riddance to last season
Here's Vermont snowfall south-to-north for 2014-15:
Stratton 156, 82%
Okemo 129, 76%
Killington 197, 81%
Sugarbush 249, 93%
Mansfield Stake 184, 82%
Stowe 290, 93%
Smuggs 294, 91%
Jay 294, 90%

There's nothing particularly out of line in that list above, and it shows that northern Vermont was actually a bit closer to long term average than southern Vermont.

…I don’t think there’s any argument to be made for expecting relatively low snowfall at Jay Peak due to its distance from this past season’s nor’easter storm track. Based on the data, it looks like the entire state of Vermont was out of the storm track, and if anything, those “alternative” methods of getting snow that affect the Northern Vermont resorts were the most positive influences. Based on the south to north trend, one could make an argument for Jay Peak possibly being on the higher end of snowfall relative to average. I’m still blown away by those Southern Vermont snowfall numbers though – it seemed like every storm that hammered the Boston area was certainly hitting the Southern Vermont resorts with more snow than we were getting up north. I know for a fact that some of those Southern New England storms hit the southern resorts with more snow, so it boggles the mind how Okemo and Stratton can have such paltry snowfall numbers and percentages. I do measure snowfall in 6 and 12-hour intervals, but I recorded more snow at my house than what’s shown for Okemo. Unlike Jay Peak, those southern resorts really appear to know how not to get snow, but with the trends shown in Tony’s data Jay Peak could easily have done relatively well like their numbers suggest.
 
I figured that JSpin would answer admin's questions quite thoroughly. :)

While I believe that the overall climatology of the Northern Greens has been explained, I (and others) still have hard time believing why Jay would get materially more snow than Mansfield. Mansfield is a much broader and somewhat taller peak (the Greens are 2,500+ on an ideal N/S axis for 15 miles from east of Jeffersonville to south of Bolton vs. about 3 miles of comparable elevation around Jay) that should wring more not less snow out of orographic uplift. When I make the upper/lower adjustment for Jay, the long term averages are 326 for Jay, 324 for Smuggs and 315 for Stowe (powderfreak). Statistically these are essentially the same number, and from a skier's perspective (Liz has mentioned this) Stowe tends to have the overall best conditions because of the extreme wind exposure at Smuggs and Jay.

The other point for which I've never been told an explanation is how snowfall just falls off a cliff as you go north from Jay. Mt. Sutton tops out at 3,000 feet 12 miles from Jay (same stats as Bolton vs. Mansfield) yet gets about 200 inches, barely more than Stratton.
 
Tony Crocker":3j2ygg7q said:
I figured that JSpin would answer admin's questions quite thoroughly.
Yes, thanks to JSpin for answering Admin's rant -- I mean questions -- thoroughly! :-D

Tony Crocker":3j2ygg7q said:
The other point for which I've never been told an explanation is how snowfall just falls off a cliff as you go north from Jay. Mt. Sutton tops out at 3,000 feet 12 miles from Jay (same stats as Bolton vs. Mansfield) yet gets about 200 inches, barely more than Stratton.
I'm interested in learning that as well. Sutton gets significantly less snow but also very little of Jay's wind.

And talk about falling off a cliff, as mentioned in my 2010 TR, Orford gets in the 160s and look how close everything is up there. From Orford's Giroux peak, that's Jay in the far right and Owl's Head on the left, which I believe gets in the mid-100s.

file.php
 
Tony Crocker":154uxl26 said:
I (and others) still have hard time believing why Jay would get materially more snow than Mansfield.
Simple, Mansfield is more in the shadow of the Adirondacks from the Alberta Clipper systems.

Tony Crocker":154uxl26 said:
The other point for which I've never been told an explanation is how snowfall just falls off a cliff as you go north from Jay. Mt. Sutton tops out at 3,000 feet 12 miles from Jay (same stats as Bolton vs. Mansfield) yet gets about 200 inches, barely more than Stratton.
1,000 feet less elevation, hence less orographic effect. It's also a narrow ridge oriented almost precisely east/west, which also diminishes the orographic effect to moisture streaming in from the west.
 
admin":1w26o77p said:
1,000 feet less elevation, hence less orographic effect. It's also a narrow ridge oriented almost precisely east/west, which also diminishes the orographic effect to moisture streaming in from the west.
As noted in my original question Bolton and Sutton have the same peak elevation around 3,000 feet. I do buy the east-west orientation as a reason for diminished snowfall. Perhaps that explains Chic-Chocs vs. Presidentials also per Patrick's comments that snow does not last as long in the spring in the Chic-Chocs.
 
Here's the helpful Jay/Townships map that Patrick posted in the Orford thread -- he wrote "lines represented the general or main orientation of the trail network. As you can see, most of them face North."

file.php
 
Fraser didn't give me a fixed length limit for these season roundups, but he clearly wants them in the general overview format of what he does for the Alps and not the lengthy detail that I put on bestsnow.net . I did touch on the issue of top vs. mid-reporting in the case of Alyeska because it's such an extreme example, and if you're going to accept Jay's upper number, you have to accept Alyeska's much larger upper number.

I have no problem defending the methodology of using mid-mountain for a "Most Snow" or "Top Ten" article, and I was careful to state "mid-mountain" explicitly. I don't think there's any question, top-to-bottom, that Alta had more snow than Jay. The true closest competitors were Revelstoke, Breck and A-Basin. Given unresolvable differences in reporting, you could make a case for any of those 3.
 
Admin":l6z0muzj said:
Tony Crocker":l6z0muzj said:
I (and others) still have hard time believing why Jay would get materially more snow than Mansfield.
Simple, Mansfield is more in the shadow of the Adirondacks from the Alberta Clipper systems.

While the snowfall collection and reporting at Jay Peak Resort is a bit of a mystery, the high snowfall isn’t just marketing and hype; there are a number of factors potentially playing into increased precipitation/snowfall for the Jay Peak area vs. Mt. Mansfield. I’ve highlighted four elements below:

Shadowing: Admin is exactly right with his comment above. This is one of the key factors believed to play into that snowfall bump at Jay Peak over resorts a bit farther to the south – and the trend continues right down the spine of the Greens, with decreasing snowfall as one heads south and mountains are more and more in the shadow of the Adirondacks. Due to their different geological origins, the ‘dacks are more of a “clump” of mountains vs. an optimal snow-grabbing “spine” like the Greens, but the ‘dacks are still quite a formidable range of peaks, reaching over a mile in height. With all those prevailing Alberta Clippers coming in from the west and northwest, woe to thee who is east, or especially southeast, of that range.

Orientation: Another factor that appears to play into the extra snowfall at Jay Peak is the orientation of the Green Mountain spine in that area – I’ve seen Powderfreak point this out in discussions on the topic. People may think of the Greens as spine running directly north to south, but there are some very important subtleties to that overall orientation. The Greens actually bend to the northeast in the northern part of Vermont (see topographic map below), placing them even more optimally perpendicular to the prevailing northwest winds and moisture than points farther south. Jay Peak is sort of the extreme case here, with the spine having bent the farthest by that point and more optimized to catch the northwest winds. Note that although Jay Peak is often spoken of as being very isolated, from the topographic map below, one can see that the Green Mountain spine is still clearly alive and well up there near the Canadian border, even if Jay Peak has a bit more prominence above other elements of the spine in the immediate area.

vttopographicmap2.jpg


Isolation: So as noted above, the Green Mountain spine is still present up near Jay Peak, but apparently the mountain has still got enough local prominence/isolation to enable orographic upslope enhancement in essentially every direction. You can see some aspects of this on the map below. Look to the east of Jay Peak and you won’t see mountains, but look to the east of Mt. Mansfield and you’ll find the Worcester Range. Perhaps even more important is the fact that Mansfield is entrenched in the spine, which doesn’t optimize orographics from the north and south. Powderfreak spoke of this in a post at American Weather:

“Jay is in the best location for a ski area in the eastern U.S... no doubt. On Mansfield we have high terrain south of us and north of us so we don't really upslope on a due southerly flow or due northerly flow. However, any easterly or westerly component to the wind will upslope over 3,000ft between the lower elevations east/west of the mountain, and the 4,000 ft ridgeline.

In general though, no one can beat Jay for pure orographic fun.”

Latitude: It’s only occasionally that a critical rain/snow/mix line will line up between Jay Peak and the resorts just to the south, but when that does happen, even just transiently, it’s yet another bump in Jay’s snowfall numbers relative to those other resorts.

There may even be other factors in play beyond the four I highlighted above, but people can probably get the picture at this point. Jay Peak is regionally in an optimal position for getting snow. Even the weather models, especially the mesoscale models that are finely attuned to account for effects of local topography, reveal the propensity for enhanced snowfall in that area. Note that these models are presumably unbiased, simply taking into account the atmospheric dynamics and terrain orographics, and I can’t even count the number of times that I’ve looked at the model prognostication maps to see the QPF maximum sitting over Jay Peak. Time and time again in their forecast discussions, the meteorologists at the National Weather Service Office in Burlington will point out how Jay Peak comes up as a jackpot of precipitation on the models, especially when those Alberta Clipper type systems come though. I grabbed a few examples from discussions

http://www.americanwx.com/bb/index.php/topic/35526-the-201213-ski-season-thread/page-14#entry1876509

http://www.americanwx.com/bb/index.php/topic/79-nne-slowly-approaching-winter/page-12#entry62903

http://www.americanwx.com/bb/index.php/topic/37693-nne-winter-thread/page-10#entry1887098

http://www.americanwx.com/bb/index.php/topic/36386-nne-fall-2012/page-28#entry1839120

http://www.americanwx.com/bb/index.php/topic/37693-nne-winter-thread/page-18#entry1895185

http://www.americanwx.com/bb/index.php/topic/31283-christmas-sunday-night-windex-potential/page-7#entry1221975

http://www.americanwx.com/bb/index.php/topic/38417-nne-winter-thread-ii/page-5#entry1933779

The examples above are just a few posts above that came up in a search at American Weather, but even the impartial mathematics of the weather models point toward higher precipitation/snowfall at Jay Peak. I’ll message Powderfreak to see if he has any additional insight in the snowfall/snow totals at the mountain that might be useful in Tony’s understanding of the snowfall totals that are reported.
 
Admin":1imkpaur said:
The fact is that Jay's summit is a windswept point of almost solid bedrock right at tree line on an already notoriously windy mountain. Jay officials have a hard enough time keeping any snow there at all, as evidenced by the snow fencing lining the upper Vermonter and Northway trails, the two runs that leave the Sky Haus tram top station. Without that fencing, snow would be blown straight to Canada. Instead, that fencing creates drifts that may be redistributed and groomed by snowcat to cover those two trails. I personally can't imagine how anyone could accurately measure snowfall in that kind of environment. And with such a cold, rain-free winter, why in the world would there be such a discrepancy between the upper mountain and lower mountain figures? All of this leads me to suspect that the upper mountain snowfall figure is complete fantasy.

Regarding the bold...the differences in upper mountain snowfall in the Greens is not tied to rain/snow events. For example, this past season I measured as diligently as one possibly can in a mountain environment on two snowboards, and came up with 170" at the base and 284" at the summit. I've done the numbers before and regardless of the type of winter, the upper mountain plot (3,014ft) will receive somewhere between 30-40% more than the base at 1,550ft. Its almost fail-proof. If the upper plot gets 300", the base will be around 200" or at least that's the general association.

The upper mountain just gets more precipitation in general for one. I know its hard to conceptualize, but during our upslope snows and in general most of the snowstorms, the upper elevations are in a saturated environment allowing much better dendrites to reach the surface (fluff factor) and it also saturates earlier. Often our big fluff storms will occur due to orographic lift where you are looking at near 100% RH at the summit and 50% at the base. That drier air in elevation will shrink the dendrites and just cause general evaporation. I'll often find gradients like 2-3" at home at 750ft, which increases to 5-6" at 1,500ft and then will go to 10+" above 3,000ft. Orographic snows often will have a much larger elevational difference than nor'easters or synotpic storms where the low levels are saturated to a 90% RH or higher straight to the valley floors. You find a more evenly distributed snowfall in those big storms. Its the light to moderate systems like Alberta Clippers where you can get 10" of fluff at 3,000ft and only 4-5" at 1,500ft, as those clippers are usually working with a lot less moisture, so to get the really good snows you want to be closer to the LCL (lifting condensation level) where the RH hits 100%. As air is lifted forcibly by the terrain the RH increases as the air parcel rises and cools. We can often have steep lapse rates in the orographic events and the terrain forcing locally results in an environment where the precipitation maximum is right over the crest.

So the precipitation maximum is right over the crest (literally). Even now in June with tropical rains, our base area rain gauge is running 80-90% of the summit...and that's with tropical rains where evaporation isn't as big of an issue as it is in dry winter air. But doing the math, as I said the larger differences are in the fluffy orographic snowfalls and alberta clippers. These fluffy snowfalls have high ratios, as J.Spin's data can show you can get even 50:1 ratios at times. Lets say 40:1 ratios are in place, even a 0.1" precipitation difference between the base and summit will result in a 4" snowfall difference. So take an upslope event where 0.4" of QPF falls at the summit, and 0.25" falls at the base...that can be 16" on the upper mountain and 10" at the base. With high ratio snowfall, very small differences in total liquid can create big differences. Now, lets say there's a big difference in RH that ranges from 100% in the cloud at the summit and 60% at the base which causes the dendrite arms to shrink as the snow falls. So now the summit is getting 40:1 ratios and the base is only getting 25:1 ratios (still really fluffy snow and you wouldn't really be able to tell the difference). In this case you have different ratios occurring due to the dry air in the low levels, and the summit picked up a little more moisture. This example with 0.4" of QPF vs. 0.25" of QPF would result in snowfall at the summit of 16" and 6-7" at the base.

Meanwhile take a synoptic nor'easter that drops 1.2" QPF at the summit and 1.0" at the base at 10:1 ratios...that's just a small range of 10-12".

I can't explain it fully but I can say that there is certainly a big difference in snowfall between base and upper mountain at Stowe, regardless of temperatures. If anything, the colder winters have more high ratio snowstorms which are where the larger differences can occur with even small liquid differences. Its to the point that local skiers expect significantly more snow in the higher elevations...such that if they pull into the parking lot with 7", they are expecting double digits up high. Snowfall is elevation dependent not only in rain/snow situations, but in a lot of our local Green Mountain snowfall due to orographics. I would also argue that the northern Greens will have a larger range of base to summit snowfall than any other region in the Northeast because of the local effects.
 
Tony Crocker":39jw183u said:
I figured that JSpin would answer admin's questions quite thoroughly. :)

While I believe that the overall climatology of the Northern Greens has been explained, I (and others) still have hard time believing why Jay would get materially more snow than Mansfield.

Do you believe that Mansfield gets materially more snow than Killington or Sugarbush? The Jay to Mansfield difference is very similar in the jump up that the Bolton/Stowe/Smuggs stretch has over the Killington or even Sugarbush area.

Climatologically speaking in the Northeast, snowfall increases as you head north all other things equal. So regardless of topography, Jay Peak would average the most snow in VT because its the furthest north. Personally, I believe Jay Peak gets the most snow in Vermont. It makes sense in that there is a very clear trend in summit snowfalls as you go from Mt Snow to Killington, and Killington to Sugarbush and Sugarbush to Stowe and Stowe to Jay. Each are only one county north of the other, but there is a marked difference often at the end of the season.

While I say that they get more snow, I'm skeptical the difference is as large as it turns out. I have some inside information on Jay's snow reporting from a Lyndon State College student that is good friends with a former snow reporter there.

1) They have no set stakes or any true system for measuring snow. The person stated its too windy and snowfall varies too much to only measure in fixed locations. The range of snowfall given on the report is there to give you an approximation of what you'll find on the hill. Most days it could be 0-24".

2) Its mostly an eyeball and gut feeling on snowfall. Snow Reporters can get very good at estimating snowfall over time, but when giving snowfall ranges what often ends up happening is the upper number is the drifted side of the trail. As skiers we are drawn to the "deeper side of the trail" so say you ski a run and the whole right side it was knee deep and billowing. "There was at least 15 inches out there!" That's what happens when you don't measure in the same place every single time. You end up almost cherry picking the deep lines and that's how much snow fell.

3) The upper number is not necessarily the summit snowfall. Its just the "higher end" of what you'll find out on the hill. Whether that means drift depths or what I have no idea. This source said they'll often take their first runs on a powder day down The Face and in that area of terrain. Like Admin said, the ridgeline is wind-swept and barren rock a lot of the time. That snow has to end up somewhere. It usually ends up on The Face Chutes. Apparently it fills in fairly evenly too. So 12" falls and it ends up being 18-20" in The Face Chutes. The argument can be made that the Snow Report is showing you snowfall you can expect to ski through. So if you are skiing through 18-20" of snow down The Face off the Tram, that can be the snowfall they go with. How would you know that's not what fell? Skiers and riders are floating through 20" of snow up there! It can almost be an issue of the difference between "snowfall" and "new powder in the summit glades". At Mansfield, it would be like measuring in the Bypass Chutes or anywhere on the Kitchen Wall (which probably gets 400" of snowfall and has depths of 10-14 feet) on the very high east side of the crest. If I wanted to, I could easily find a spot at Stowe that gets 350-400" a year under the cliffs of the Kitchen Wall. Skiers will often mention that the snow is always deeper there...well yeah, it is, it blew in off the ridgeline. That's why I measure at 3000ft and not 3600ft up under the cliffs.

4) The mountain is very windy and its nearly impossible to tell exactly what fell. That said, the attitude is when in doubt, go higher because no one can disprove it. A certain Johnson State College professor stated this year that his students did not agree with the Jay report quite a bit...often lamenting the fact that they'd throw numbers out but then just say it all blew in the woods...so that you spend all day trying to find the 6-8" that seemed more like 4-5".

I think Jay Peak could back up their snowfall claims if they situated a stake in the "right" location in the glades of the Face Chutes under the tram. I could bump Stowe's snowfall if I measured in the upper Bypass Chutes region, too, where 5" can turn into boot deep powder turns. Alta could probably double their snowfall if they measured in the "right" spots, too.

Its not an exact science, but I wish some mountains would go through more effort to show that they are at least trying to do it consistently. I'll often post photos of my snowboards and stakes to Stowe's social media channels and photos of the day, etc. Its the easiest way to show people how much snow fell and it builds trust fast. I can tell via social media, as well as what's posted online in ski forums, and just by word of mouth on the mountain that I've done a good job building up trust in the snow report....to the point that people think its under-reported. But its not. Skiers are just an optimistic bunch and go in search of drifts and deepest snows. Yes, 8" can turn into 16" if you know where to go. But that doesn't mean 16" of snow fell from the sky.
 
Informative comments by powderfreak above. Legitimate snow measurements should be taken where wind neither adds to nor subtracts from snow totals in the long run. I'm sure that's the objective at Alta Collins and also where powderfreak measures at Stowe. Evidently this is not the case at Jay.
 
Just to :stir: on Mt. Sutton again, here are JSpin's stated reasons for Jay's snowfall exceeding Mansfield's.

1) Shadowing. Sutton is at least as clear of the Adirondacks as Jay.
4) Latitude. Sutton is of course at least as far north also.
3) Isolation. I actually disagree with this one. By my experience isolated peaks tend to get less orographic uplift as weather can go around them whereas it must be forced over a longer perpendicular set of mountains. See Big Sky vs. the Tetons as Exhibit A. At any rate we can't have it both ways saying isolation enhances Jay's snow while diminishing Sutton's.
2) That leaves Orientation and 800 feet lower altitude (though still the same as Bolton's) as crashing Sutton's snowfall ~40% below Jay's. And JSpin's topographic map shows the relief just north of the border still on somewhat of a SW-NE orientation.
 
jamesdeluxe":1cuyhgwc said:
Why are you busting on Sutton? The annual snowfall quote on their website isn't inflated: 500 cm/approx 200 inches.
Not busting on Sutton. I just think the huge disparity between Sutton and Jay given their proximity is curious. And when you go through JSpin's criteria it becomes even more curious. It's like the difference between LCC and the Park City group. In nearly all such situations the drier area is in the precipitation shadow of the snowier one, which is not the case here. Burke, which is barely higher than Sutton and IS in the precipitation shadow of the Green Mt. spine, claims 248 inches.
 
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