NNE Cold Season Thread 2020-2021

[LaGrangewx]

56 minutes ago, J.Spin said:

 

Yeah, the snowpack topped out at ~18” here the other day, and it’s dropped a couple inches to 16” now.  My last snowpack liquid analysis was on the 19^th, when then snowpack had just shy of 2 inches of liquid in it.  Based on what we’ve picked up in the past several days, we’re probably in the range of ~2.5” of liquid at this point?

As I mentioned the other day, it looks like the NOHRSC modeling for our site (plot below) had the snowpack SWE a tad high because some of the Winter Storm Malcolm liquid when the temperatures were marginal probably percolated down through the snowpack here, and their modeling didn’t seem to account for that.  They have now done a couple of assimilations of the actual data I’ve sent in (green lines on the plot), and I think they’ve reigned in the disparity a bit.

The NOHRSC plot currently has our average snowpack density here at around 20%.  As PF mentioned, there’s plenty of fluff on top in the form of dry snow from these recent days, so I know we’ll see some settling of that.  But, there’s that very stout middle layer from the dense part of Winter Storm Malcolm that won’t settle much, and then a sugary/faceted layer below that representing the previous snowpack.  I think it’s generally going to be the top portion of the pack settling as we go forward, so we’ll settle some, but it’s not as if the snowpack depth will get cut in half.

Been looking a lot at NOHRSC data. Is it modeled depth and then also takes into account reports? If you look several years back it seems to be a lot less accurate than it is now a days. Like for example it will show the high depths on Mansfield at elevation but then it didn’t show the same in the ADK high peaks when I’ve personally hiked there with snow pack into early June 

[J.Spin]

15 minutes ago, LaGrangewx said:

Been looking a lot at NOHRSC data. Is it modeled depth and then also takes into account reports? If you look several years back it seems to be a lot less accurate than it is now a days. Like for example it will show the high depths on Mansfield at elevation but then it didn’t show the same in the ADK high peaks when I’ve personally hiked there with snow pack into early June 

I’ve been checking it out for our site for a few years now, ever since Ginx pointed it out and the fact that CoCoRaHS stations are in there.  I’ve found it generally to be quite good for my site.  It definitely takes the empirical observations into account at times (see the data assimilation points in the plot) to at least augment the modeling, but they don’t seem to just immediately lock the modeling to the actual observed data points when they do the assimilations from what I’ve seen (and as you can see in the plot below).

I don’t really follow the data for other sites to see how well its modeling reality, but I bet the meteorologists can provide more input on that.  I’d suspect results are going to be better with the modeling if you’ve got consistent data input, such as at a CoCoRaHS or co-op site, but it’s not too hard to imagine that if you’ve got a site with zero empirical observations and 100% modeling (I’m not sure if they do that), the output could get quite far off from reality.

[LaGrangewx]

13 minutes ago, J.Spin said:

I’ve been checking it out for our site for a few years now, ever since Ginx pointed it out and the fact that CoCoRaHS stations are in there.  I’ve found it generally to be quite good for my site.  It definitely takes the empirical observations into account at times (see the data assimilation points in the plot) to at least augment the modeling, but they don’t seem to just immediately lock the modeling to the actual observed data points when they do the assimilations from what I’ve seen (and as you can see in the plot below).

I don’t really follow the data for other sites to see how well its modeling reality, but I bet the meteorologists can provide more input on that.  I’d suspect results are going to be better with the modeling if you’ve got consistent data input, such as at a CoCoRaHS or co-op site, but it’s not too hard to imagine that if you’ve got a site with zero empirical observations and 100% modeling (I’m not sure if they do that), the output could get quite far off from reality.

Thanks Great explanation as always. I think it may struggle a bit truly modeling the highest of elevations in the mountain areas without a lot of obs like you said. Especially later season when the surrounding area is melted out. Outside of the infrequent reports from the Lake Colden Ranger there are no obs in the main high peaks area. Whiteface is quite removed from that area and has its own weather to an extent. Hiked Marcy early June 2018 and there was a solid snow pack from 4000’ up. Right now I just looked nohrsc has 20-30 in the high peaks when the Colden Ranger reported 4 feet in the high elevations. NOHRSC does seem to have the Presidentials modeled a lot better most likely because of the better obs

[backedgeapproaching]

1 hour ago, CoastalWx said:

The main threads can be a clown show sometimes, but it’s good entertainment. I know you never met most of us before,  but it’s a good group of people in the New England forum, even though Phin hated us and pushed for subforums. 

I really wish the eastern forum archives were around somewhere..I would love to read some of those threads when all you weenies were in the same one.  Must have have been some nice melts and battles. 

[Ginx snewx]

40 minutes ago, J.Spin said:

I’ve been checking it out for our site for a few years now, ever since Ginx pointed it out and the fact that CoCoRaHS stations are in there.  I’ve found it generally to be quite good for my site.  It definitely takes the empirical observations into account at times (see the data assimilation points in the plot) to at least augment the modeling, but they don’t seem to just immediately lock the modeling to the actual observed data points when they do the assimilations from what I’ve seen (and as you can see in the plot below).

I don’t really follow the data for other sites to see how well its modeling reality, but I bet the meteorologists can provide more input on that.  I’d suspect results are going to be better with the modeling if you’ve got consistent data input, such as at a CoCoRaHS or co-op site, but it’s not too hard to imagine that if you’ve got a site with zero empirical observations and 100% modeling (I’m not sure if they do that), the output could get quite far off from reality.

I found it to be very accurate for my site.

[jculligan]

The lady wanted a bit of an adventure today, so we wandered up to the First Aid cache at the floor of Tuckerman Ravine late this morning. The wind was absolutely insane at Pinkham Notch (car shaking gusts as we were getting geared up) and you can imagine things were off the hook at the floor of the ravine. The avalanche danger was lowered to "moderate" this morning, but the advisory indicated that there was a low probability of avalanches up to D3 (large and destructive; the type that can take down trees) if something were to trigger...and with the raging wind and low visibility, we wouldn't even see/hear it coming. For that reason, the First Aid cache was as far as I was comfortable going since anything beyond that is most definitely avalanche terrain.

Between the skier traffic yesterday, and the incredible wind today...the Sherburne Trail is down to very hard snow with sections of exposed rock. I think I'll be back to lapping groomers this week until we can get more snow. I would imagine the ravines were pummeled to the point that the avalanche rating will likely be reduced further this week, but "slide for life" conditions will prevail instead. No interest in that. The backcountry is once again on hold around here.

[wxeyeNH]

.  Perhaps this is a bit of a sleeper and it will end up being a snowy period, especially for central areas that missed out of the upslope.  Here is 12Z and 18Z comparison

[PhineasC]

Yeah, 18z GFS is kinda bullish keeping snow showers going WED to SAT.

The other models have a signal but less of a surface depiction right now. We will see how this trends.

[alex]

Back home from Conway. It still amazes me to experience the difference in sensible weather that the upslope areas create. North Conway had pretty thin cover and looked almost spring like. Sun was out, and you could even see mount Washington. You'd have no idea that Bretton Woods was in the snow and clouds all day. 

Driving up, you get into a few flurries starting in Hart's Location. Once you get to the 2 waterfalls just before the AMC, it was moderate snizzle and snow covered roads (and it's that way till my house). Just amazing. 0.4" added today - so very light stuff 

[wxeyeNH]

Just now, alex said:

Back home from Conway. It still amazes me to experience the difference in sensible weather that the upslope areas create. North Conway had pretty thin cover and looked almost spring like. Sun was out, and you could even see mount Washington. You'd have no idea that Bretton Woods was in the snow and clouds all day. 

Driving up, you get into a few flurries starting in Hart's Location. Once you get to the 2 waterfalls just before the AMC, it was moderate snow and snow covered roads (and it's that way till my house). Just amazing. 

Alex,  just a beautiful (cold) sunny day over this way.  Even looking north towards Franconia Notch was mostly sunny.  The is the only downside of living where you do weatherwise is that on a NW flow you seem to clear out last.  Much more cloudiness, even in summer.  Hum,  maybe this week I can score more snow than you.  Have a good week.

[PhineasC]

13 minutes ago, alex said:

Back home from Conway. It still amazes me to experience the difference in sensible weather that the upslope areas create. North Conway had pretty thin cover and looked almost spring like. Sun was out, and you could even see mount Washington. You'd have no idea that Bretton Woods was in the snow and clouds all day. 

Driving up, you get into a few flurries starting in Hart's Location. Once you get to the 2 waterfalls just before the AMC, it was moderate snizzle and snow covered roads (and it's that way till my house). Just amazing. 0.4" added today - so very light stuff 

We make that comment every time we drive into Conway. Noticeable in the summer too. We'd leave Randolph at around 80 and in Conway it would be full sun and like 90. Cranmore must be suffering this season.

[powderfreak]

4 hours ago, CoastalWx said:

I’m pretty sure IZG to LEW is the center of screwjie this year. 

There’s some sort of force field there.

[J.Spin]

On 1/22/2021 at 6:36 AM, powderfreak said:

Mushroom land out there from the heavy wet snow followed by days of windless 3-4" fluffers.

Yeah, awesome upslope-land views over the past few days.  This was definitely on my mind when I was out for a tour yesterday.

The consistent snows and temperatures we’ve had over the past several days certainly had me pretty certain that the snow quality was there for lift-served skiing, but the appearance of your arctic hounds led me to go touring instead.  When I saw highs in the single digits F for Bolton Valley yesterday, there was no way I wanted to sit still on the lifts in the wind vs. generating my own heat down in the protection of the forest.

I got up to the Village around midday, and temperatures were indeed in the mid-single digits F as the forecast had suggested.  Between all the backcountry touring and Nordic folks that I saw, there were plenty of people out on the lower trails, but farther out into the higher trails by the Bryant Cabin, I saw probably a handful of groups. Overall, you could tell by the vibe that people felt it was great weather for these types of activities.

The additional 4 inches of fresh champagne that the resort had picked up really just served to top off the already crazy levels of fluff that covered everything.  I saw some great views as soon as I arrived in the Village, so before gearing up for my tour, I took a quick walk around the Village and grabbed some scenic shots of the snow.  Once I started my tour and got into the forest, the amount of snow everywhere was just crazy – it was caked so heavily on the trees that you were surrounded by it on all sides.  Starting up the Bryant Trail was like walking into some sort of white cathedral.

I made depth measurements of the snowpack during my tour, and I found generally 26-27” around the 2,000’ level, and many spots that are getting dangerously close to 40” up near 3,000’.  That’s pretty consistent with what the Mt. Mansfield Stake is showing.

At the start of my tour off Heavenly Highway I was on some steep, 30+-degree slopes, and I was setting off sloughs that definitely spoke to the relative snowpack instability from the continuous day after day after day of snows without consolidation.  I was perfectly safe where I was the very dense (too dense for great turns where I was exploring actually) forest, but I immediately though about how I wouldn’t want to be exposed in the ravines.  So I guess it wasn’t entirely surprising to come to the forum to find a conversation about slides in Tuckerman.

A few shots from yesterday’s tour:

[powderfreak]

Had a decent sunset this evening.

[alex]

Just saw this picture on Instagram, really shows how localized upslope can be on days like today

[dryslot]

Just getting back on the computer after a trip out yesterday riding on the trails, For the conditions, It was a very good day all things considering, The windmills on top of Kibby Mtn are impressive listening to them in the wind.

[J.Spin]

3 hours ago, PhineasC said:

Yeah, 18z GFS is kinda bullish keeping snow showers going WED to SAT.

The other models have a signal but less of a surface depiction right now. We will see how this trends.

The modeling definitely seems to be showing a northward trend with respect to that system, so it looks like we have the potential to get in on some precipitation even this far north.  And indeed like you said, the other models do show that signal for moisture hanging around, just not as pronounced as what the GFS had.  We’ll have to see where the trends go with this over the next couple of days.

I was actually surprised at how quiet this next week looked in the modeling; we typically won’t have a week that quiet around here in the northern mountains unless full blown arctic high pressure moves in and leaves us in that dry, frigid air.  Even during that very slow week before this past one, we still had 2 to 3 inches from those very weak bread and butter systems.  There’s almost always a little something that pops up, and the mountains do their thing to at least get some flakes out of it.

[PhineasC]

00z GFS looks even better. Let’s see if the rest of the suite follows. 

[powderfreak]

Car said -6F leaving my house this morning.  Finally felt really cold...that nostril freezing cold as soon as you step outside.

Looks like MVL hit -8F for the min.  Crazy that’s only like 10F below normal and it feels like the face of the moon.  Too used to walking outside to like 18-24F every morning.

[bwt3650]

18 hours ago, J.Spin said:

 

LOL, don’t worry bwt, “epic” is totally subjective and fine to use whenever you want.  As a skier, let’s just say that’s clearly a good sign if the word is even coming up in the conversation.  Indeed, as PF alluded to, as a scientist, what I like about this forum is that one can dive into the data and actually get a sense for where things really stand vs. just simply relying on hype, poor memory, weenie hyperbole, agenda, opinion, anecdotes, recency bias, etc. etc.  And I love that the meteorologists on here will often pull out real data to shut down misconceptions.

 

I get it that for many folks, the forum is more focused on the entertainment aspect, and that’s great, but I really like the science/data-driven side a lot.  A great analogy for what the forum is like from my perspective (and I mean the main threads for the most part, the NNE thread is pretty even-keeled), is like listening to Dr. Fauci talk about the COVID-19 pandemic on one hand, vs. listening to Donald Trump talk about the pandemic on the other.  One of those presentations is more for show, publicity, entertainment, popularity, etc., whereas the other deals more with the nuts and bolts.  One (you can probably imagine which one) is rather cringe-worthy from the perspective of someone who has been training and working in science for decades, and the other just clicks and makes sense.  I’m clearly biased in my preference of course (Dr. Fauci was technically my boss during my years at NIAID), so it’s posts of that sort where I put a lot of my efforts.

 

It is funny to think of us pulling out the data to tell folks how excited they should be, LOL.  Hopefully I’m not overselling the past week with this one:

 

All good.  I definitely appreciate the data and scientific approach too.  It kind of keeps us grounded.  I love it up here and even more so, love learning about the micro-climate and the meteorology behind, “wow, it’s snowing again.”  I’ll keep the adjectives and pictures coming and you keep the data and science.  

[bwt3650]

5 minutes ago, powderfreak said:

Car said -6F leaving my house this morning.  Finally felt really cold...that nostril freezing cold as soon as you step outside.

Looks like MVL hit -8F for the min.  Crazy that’s only like 10F below normal and it feels like the face of the moon.  Too used to walking outside to like 18-24F every morning.

The kind of cold and wind yesterday that made your face covering turn to solid ice from breathing...yeah, it was a true hardcore skiers day yesterday.
 

 Coolest thing seeing the wind blow the clouds up over certain parts of the mountain.  It was like watching upslope in a science experiment.  Obviously, not enough moisture to make snow, but it was like watching the process. Can’t really tell, but in the last picture, the clouds are almost shooting straight up over the peak.  The first two are from tram side (jfk) where it was completely empty with the flyer on wind hold. Best bet was to duck in the glades and get out of the wind.

[J.Spin]

22 hours ago, dendrite said:

Curious how much water you have in your pack right now. I think I remember your pack being around 18” the other day? I usually say that the pack quickly likes to get back to 10:1 so it makes sense how those 8” new quickly compact down. I saw it for myself in December with 34” of 20:1 getting cut in half in 2 days.

I just cored the pack for CoCoRaHS today (I think they encourage folks to do it on Mondays anyway) and got 2.51” of liquid.

It was actually a good time for a check on the water in the snowpack because there wasn’t any new snow yesterday, which was the first time since Christmas that I haven’t recorded at least a trace here.

[dendrite]

Just now, J.Spin said:

I just cored the pack for CoCoRaHS today (I think they encourage folks to do it on Mondays anyway) and got 2.51” of liquid.

 

It was actually a good time for a check on the water in the snowpack because there wasn’t any new snow yesterday, which was the first time since Christmas that I haven’t recorded at least a trace here.

 

That’s pretty good. You get enough fluff that it still really piles up. Someone east of Ontario can pull 3ft and it’s compacted down to a foot in a week, but you’re more like the Tug hill where you are.

[tamarack]

 

10 hours ago, dryslot said:

Just getting back on the computer after a trip out yesterday riding on the trails, For the conditions, It was a very good day all things considering, The windmills on top of Kibby Mtn are impressive listening to them in the wind.

 

Yesterday was the first day this cold season that I saw any sign of blowing snow, though nothing like the pic - only Friday's 1/2" to work with here.  All other snow here would've needed yesterday's MWN gusts to be moved.  Two sleds went by the house yesterday afternoon, first ones in a while.  Hope they bombed straight down the road; if they turned left onto the trail thru our woodlot they had 500' of rock-dodging then 1500 of teeth-chattering icy track.

[alex]

The never ending sunshine blocking flurries continue here

[PhineasC]

Mostly clear here. 

[powderfreak]

12z NAM has many hours of snow... going to be some weird banding but several models have liked MPV to J.Spin and maybe up to here.  It almost has a standing wave look instead of banding, so maybe there’s some weird terrain stuff going on.

That pattern looks like mid-level banding with a blocked SE low level flow.

 

[powderfreak]

Yup for sure.  It’s the blocked SE flow at 925mb under mid-level banding where Washington County is. Shocker, JSpin does real well with this look but we usually do pretty good in Stowe too.

 

[dryslot]

12 minutes ago, powderfreak said:

12z NAM has many hours of snow... going to be some weird banding but several models have liked MPV to J.Spin and maybe up to here.  It almost has a standing wave look instead of banding, so maybe there’s some weird terrain stuff going on.

That pattern looks like mid-level banding with a blocked SE low level flow.

 

That's kind of an odd qpf distribution the Nam has.

[PhineasC]

16 minutes ago, dryslot said:

That's kind of an odd qpf distribution the Nam has.

Has me in a relatively dry zone. A kinda weird setup so we will see what happens. I don't have much experience with these inverted trough setups. 

Mood flakes are fine by me, the next event that looks promising is early Feb.