Saturday, March 05, 2011
Our next storm is coming into the area this weekend. It’s another fairly warm system, but the BTV NWS has winter storm watches up and there’s plenty of moisture with it, so it could be a foot or two of snow for the higher elevations. It looks like the northern valleys will also get into the snow however. I’ve added in BTV’s latest advisories and storm total snow forecast maps below:
That's some HEAVY wet upper elevation snows. It seems a little excessive to me BUT it’s certainly possible IMO
Thanks for that update adk, I’ve added in the BTV advisories map below. In terms of precipitation so far with this event we’ve just got a few sleet pellets in the rain gauge from last night, but light snow/flurries has broken out here as of the last 10 minutes or so.
Yeah I did see that... I think there's a chance of that but we need the GFS to work out.
I can see some of the potential that people are talking about on the recent accumulated snowfall maps from the GFS. That is a very tight gradient that unfortunately leaves many Northern New England folks out of the snowfall. The 48-hour and 72-hour maps from what looks to be the 6Z GFS have been added below:
We were around in Stowe for a bit today and also did some skiing over at Cochran’s in Richmond, and aside from last night’s sleet and the bit of snow this morning, we’ve seen just a few rain showers. Looking at the Intellicast radar, the bulk of the precipitation seems to be hanging off to our west in New York State. I checked the rain/snow gauge here at the house and there’s not even a hundredth of an inch in it.
As Powderfreak posted, the winter storm watches in this area have moved on to winter storm warnings, with 8 to 16 inches of snow mentioned. Checking the point forecast for the higher elevations around Mt. Mansfield tomorrow suggests a good shot of snow, with some continuing on into Monday night:
Tonight: Rain and snow, becoming all snow after 4am. Low around 32. Windy, with a south wind around 31 mph. Chance of precipitation is 80%. Total nighttime snow accumulation of less than one inch possible.
Sunday: Snow. High near 32. Windy, with a south wind 28 to 31 mph decreasing to between 14 and 17 mph. Chance of precipitation is 90%. New snow accumulation of 8 to 12 inches possible.
Sunday Night: Snow. Low around 9. Wind chill values as low as -8. Breezy, with a south wind 10 to 13 mph increasing to between 18 and 21 mph. Chance of precipitation is 80%. New snow accumulation of 4 to 8 inches possible.
Monday: A chance of snow. Cloudy, with a high near 25. Wind chill values as low as -9. South wind 11 to 17 mph becoming northwest. Chance of precipitation is 50%.
Monday Night: A slight chance of snow before 1am. Mostly cloudy, with a low around -7. North wind between 8 and 11 mph. Chance of precipitation is 20%.
We’re planning to be up at Stowe tomorrow afternoon for our usual Sunday ski program, but if things were to start changing over to snow early in the higher elevations like the point forecast suggests, we’d potentially head up earlier to catch the new snow. We’ve already had at least one parent who’s heard about 16-18” of snow potential, and called to ask if we were canceling tomorrow’s session. Travel concerns of course have to be taking into consideration, but this is Northern Vermont, and most people are going to be ready for this stuff. So I think we’re going with the policy that ski program will be on, and tomorrow morning people can watch the weather and decide how comfortable they are with the storm with regard to their vehicle/driving skills etc. There’s just something wrong about canceling skiing because of snow. Fortunately, it sounds like the valleys will be changing over to snow later than the high country. Our point forecast for down here in the Winooski Valley at ~500’, and the point forecast for various other valley spots in the area don’t suggest that the precipitation will change over to all snow until tomorrow evening. Once it does change over, the point forecast calls for 6 to 10 inches around here.
Powderfreak, are you going to be reporting from the mountain at all tomorrow? I know you aren’t always working on weekends, but if you are up there early, try to send on what’s happening in terms of precipitation. I’m sure the snow report will be helpful, but any additional information will be useful and we can share that with parents. As long as everything goes OK in terms of travel, I’ll certainly send on a report about what we find on the mountain later in the day. I’ve added some of the updated BTV graphics below:
Sunday, March 06, 2011
With the slow eastward march of this system, there was still essentially nothing in the rain gauge last night, but this morning I found 0.60 inches in there with light/moderate rain falling. I looked at the Intellicast colored radar and the snow depicted on there is getting close to the northwest corner of Vermont.
The latest temperature reading from up on Mt. Mansfield was 40 F, and looking at the temperature plot that hasn’t started falling yet. I added some of the latest BTV graphics below – the winter storm warnings have expanded in areal coverage and the expected snowfall has as well. The anticipated accumulations around here in the valley seem similar to the previous plot, but the projected snowfall amounts in some of the higher elevations seem to have come down a bit.
It was in the 40s F and had a spring feel before, but when we came out of mass at around 10:00 A.M. the temperature had dropped dramatically into the mid 30s F. The moderate rainfall had also become very heavy rainfall and everyone was rushing to their vehicles. I was certainly hoping that rain like that was either snow or becoming snow in the mountains, because it probably would have been 2+ inches per hour. Based on the big drop in temperatures we saw here and the reports in the thread, it sounds like snow is getting close. I’ll try to keep checking outside to get an idea of when the changeover occurs at this location/elevation. I’ll also check the gauge at that point and get a number for the liquid portion of this event.
11:30 A.M. – frozen precipitation (sleet) just started mixing in here along the Bolton/Waterbury line – I’ll go out and get the liquid from the gauge to see what the total is to this point.
Our gauge contained 0.47” of liquid, which represents the total since 6:00 A.M. this morning. Combined with the 0.60” that I emptied at that point, 1.07” of liquid has fallen here with this event so far.
11:54 A.M.: snow started to mix in here along the Waterbury/Bolton line. I was out shoveling the last of the old snow off the deck before the temperatures drop, so I was able to see the exact time that snow started to mix in. The flakes were fairly big at around 1 cm in diameter. So in this location it was 24 minutes from the first sleet mixing in to the first snow mixing in. There’s still sleet in there now among the big flakes, but I’ll update next when it’s over to 100% snow. That may not be too long because there are already periods now where the sleet is absent.
There’s been sleet mixing in with the snow occasionally, but I’d say as of roughly 12:35 P.M. we’ve been over to 100% snow. It’s certainly not heavy snowfall, I’d say light to moderate in intensity.
Event totals: 2.4” Snow/1.39” L.E.
Sunday 3/6/2011 4:30 P.M. update: Once the precipitation changed over to snow here around midday, it was steady but nothing too heavy, and the flakes were generally pretty small. Due to the potentially difficult weather however, the decision was made to cancel ski program at Stowe this afternoon, so at around 3:00 P.M. I headed up to Bolton to make a few turns there and see how the new snow was taking hold. By that point we probably had accumulated about an inch or so down here at 500’. I stopped in at the Timberline base (1,500’) and found 1-2” of new snow there, and then headed up to the main base (~2,100’) where accumulations seemed pretty similar. Up at 3,150’ I found one protected spot with 3 inches of accumulation, but in general there wasn’t anything more than a couple of inches.
The snowfall probably picked up a bit around here in the later afternoon because when I cleared the snowboard at 4:30 P.M. it had 2.4 inches of snow on it. With the sleet down on the bottom of the stack, the overall density came in at 13.3% H2O, but even with the small flakes, the snow that was on top was certainly less dense than that. The snow was probably standard synoptic stuff at around 10% H2O. I grabbed a still shot showing some of the new snow out back before dusk came in:
I hadn’t been watching the forecast too closely, and just figured we weren’t going to get too much snow out of this, since the flakes were so small and the snow was so dense. But now that I’ve seen the discussion it seems like the heavier stuff comes in tonight. One of my colleagues in South Burlington just called and said that they’ve received about 7 inches so far from this event. Here at the house I’d say we’re up to about 4 inches of total accumulation. The point forecast here does suggest about 12 to 20 inches through tomorrow:
Tonight: Snow. Low around 14. North wind between 7 and 10 mph. Chance of precipitation is 100%. Total nighttime snow accumulation of 10 to 16 inches possible.
Monday: Snow, mainly before 1pm. High near 22. North wind between 10 and 13 mph, with gusts as high as 28 mph. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
So we’ll just have to see what happens over the next 24 hours. I’ll be able to do another clearing of the board and a liquid analysis at 10:30 P.M., so it will be interesting to see how that turns out in terms of accumulation/snow density.
It is interesting to note that just the small amount of snow received from this event through 4:30 P.M. is already more than was received in the entirety of March last season at this location (2.1 inches). Even if the low end of the forecasts here verify for this event, the March snow total will likely already exceed the totals from the past two Marches combined, and things would be on track for a much more typical March. I did notice on The Weather Channel that after a break during the middle of the week, there were several days featuring snow at the end of this week into next weekend, so that will obviously be something to watch as we move forward.
Some details from the 4:30 P.M. observations are below:
New Snow: 2.4 inches
New Liquid: 0.32 inches
Snow/Water Ratio: 7.5
Snow Density: 13.3% H2O
Temperature: 29.3 F
Sky: Snow (1-2 mm flakes)
Snow at the stake: 24.0 inches
It sounds like conditions will be going from good to great based on the current forecasts anyway; the latest discussion from the Burlington NWS this afternoon suggests that snowfall totals of 1 to 2 feet will be possible across a good portion of the region through tomorrow when this storm cycle winds down. While not a super huge event, the snow will likely contain a lot of denser, standard synoptic snow as opposed to being just Champlain Powder™, so it should be good in terms of helping out the snowpack as we move toward spring. Also, since this area had been out of the synoptic storms for so much of the season, this could represent the first synoptic storm to really set a bull’s-eye on our area. After a midweek lull, another storm of this type could be on the way for the end of the week into the weekend. I’ve added a couple of the updated accumulations maps from the BTV NWS below:
Event totals: 6.8” Snow/1.89” L.E.
Sunday 3/6/2011 10:30 P.M. update: In the 4:30 P.M. to 10:30 P.M. timeframe, 4.4 inches of snow fell here, indicating an average snowfall rate of 0.72 inches/hour. Since this round of snowfall accumulation doesn’t have any mixed precipitation in it, it should serve as a good measurement of the density of the snow falling with this system. It’s not quite down to 10% H2O, but at 11.4% H2O (8.8 to 1) it’s certainly less dense than the earlier sample that had some sleet/rain in it. I’m not used to eyeballing snowfall rates as well with these tiny flakes, but it’s certainly coming down out there – I went with a rate somewhere between snow and heavy snow.
Some details from the 10:30 P.M. observations are below:
New Snow: 4.4 inches
New Liquid: 0.50 inches
Snow/Water Ratio: 8.8
Snow Density: 11.4% H2O
Temperature: 26.1 F
Sky: Snow (1-3 mm flakes)
Snow at the stake: 28.0 inches
Monday, March 07, 2011
I have no doubt we hit 18" in the lower elevations... probably within in the next couple hours.
I’d say you are right on track with that Scott, we were at 16.7” as of my 6:00 A.M. report for CoCoRaHS, and looking at what’s on the snowboard from the past hour, we’re getting close to 18” total. I’m putting together my report right now and I’ll post that in a bit.
Event totals: 16.7” Snow/2.89” L.E.
Monday 3/7/2011 6:00 A.M. update: In the 7.5 hour block from 10:30 P.M. last night to 6:00 A.M. this morning, 9.9 inches of snow fell at this location, indicating an average snowfall rate of 1.32 inches/hour during that stretch. The collection interval was longer than a 6-hour period, but that 9.9 inches of accumulation was the largest individual stack I’ve measured this season, exceeding the 7.7-inch stack from back on January 12th. That January 12th stack was actually from a 10-hour interval, so last night was quite potent in terms of snowfall. This storm has been comprised of fairly small, synoptic-style flakes, and that is evident in the fairly trapezoidal structure of the stack from this morning:
It is interesting to note that the overnight accumulation contained exactly 1.00 inches of liquid, and with the fairly standard ratio snow (10.1% H2O) was perhaps the most liquid I’ve pulled from a stack. My 68 mm-diameter core sample contained 92.25 mL of liquid. The liquid event total for this event was 2.89 inches as of the 6:00 A.M. report, and I broke it down in my CoCoRaHS report comments this morning:
“T=21.0F, Sky=Heavy Snow (1-8mm flakes); storm total liquid is currently 2.89" obtained from 1.07" rain through 11:30 A.M. yesterday (3/6) followed by 1.82" as snow through 6:00 A.M. today (3/7)”
This storm is already the third largest event of the season, and with the snow on the board outside it looks like it will move into second position past the 18.0” event from early January. Also of note is that this storm has raised the snowpack here to 36.0 inches, which is the highest depth attained yet this season.
While the flakes have generally been on the small side with this event, they have become notably larger now, so I’d suspect the next round of analysis to indicate a density somewhere below 10% H2O. Flakes were up to ~8 mm at the 6:00 A.M. observation time, but now there are some twice that size, up to ~15 mm.
On a seasonal note, this storm has now produced more snow than the past two Marches combined, which only totaled 14.7 inches here. Also, with this event, winter ’10-‘11 has now moved up into the range of where the ’07-’08 and ’08-’09 La Nińa seasons were at this point. At 170.6 inches as of the 6:00 A.M. observations today, this season has actually just passed ’08-’09 (170.4” on this date) and is about 9 inches behind ’07-’08 (179.3” on this date).
Here are the numbers I’ve seen from the Vermont ski areas so far with this event, the list is from north to south:
Jay Peak: 26”
Smuggler’s Notch: 21”
Bolton Valley: 17”
Mad River Glen: 10”
Magic Mountain: X”
Mount Snow: 0”
Totals clearly fell off to the southern part of the state due to the rain/mixing.
BTV has updated their accumulations maps so that they are more in line with the expected totals, so I have added a couple of their recent graphics below:
Some details from the 6:00 A.M. observations are below:
New Snow: 9.9 inches
New Liquid: 1.00 inches
Snow/Water Ratio: 9.9
Snow Density: 10.1% H2O
Temperature: 21.0 F
Sky: Heavy Snow (1-8 mm flakes)
Snow at the stake: 36.0 inches
I just took an intermediate measurement off the snowboard at 9:00 A.M. and it showed a bit under 3 inches of additional accumulation, so snows since 6:00 A.M. have been in roughly the 1 inch per hour range in this location.
Event totals: 22.5” Snow/3.45” L.E.
Monday 3/7/2011 12:00 P.M. update: Snow continued through the morning at roughly an inch per hour, with 5.8 inches received in the 6:00 A.M. to 12:00 P.M. timeframe. The density did drop down a bit, but it was just below 10% H2O so it was still medium range and synoptic-like in density. The flake structure, which had some stellar plates and some flake aggregates up to 15 mm in diameter at times, did make the stack a bit less trapezoidal than this morning:
I ran the snow thrower through the driveway in the late morning, and it definitely took longer to clear things than usual. Biting off over 20 inches of synoptic snow at once was just about as much as my snow thrower could handle, but I used the lower speeds (even had to use a lot of the “turtle” setting) and it definitely met the challenge. I grabbed a measurement shot before I cleared the last slice of the driveway accumulation, and that came in at around 21 inches. The storm total at that point was 22.5 inches, so with the synoptic-level density of the snow, it really hadn’t been settling too quickly.
This morning’s run was certainly the deepest synoptic snow I’ve thrown in one pass, and the height of the intake on my snow thrower is only 22 inches, so that’s pretty close to the max. It is nice not to be shoveling like we did for the 2007 Valentine’s Day storm though, or we’d still be out there. Between the additional snowfall we picked up since noon and the new berm at the end of the driveway from the subsequent plowing, I need to do another pass this evening. I’ve still got my 6:00 P.M. update to write up, but I’m going to throw the rest of the snow and I’ll finish that up later.
Some details from the 6:00 P.M. observations are below:
New Snow: 5.8 inches
New Liquid: 0.56 inches
Snow/Water Ratio: 10.4
Snow Density: 9.7% H2O
Temperature: 19.6 F
Sky: Snow/Heavy Snow (1-15 mm flakes)
Snow at the stake: 39.0 inches
Event totals: 25.0” Snow/3.55” L.E.
Monday 3/7/2011 6:00 P.M. update: We spent the morning around at the house, and then we headed up to the mountain at some point after 1:00 P.M. to check out the snow and get in some storm day turns. Bolton’s Vista Quad was on wind hold, but Timberline was running well and we spent the afternoon there. I did several depth checks in the 1,500’ to 2,500’ elevation range and got measurement of 26 to 31 inches for the depth of the new snow. There were some gusty winds at times, but Timberline is fairly protected and wind wasn’t bad except on the ridgelines. I added a couple of shots of the boys below:
At 6:00 P.M. the snowboard had another 2.5 inches of snow on it, and the storm was winding down. The density of the snow had definitely dropped a lot, down to 4% H2O, so the event ended getting topped off with some fluff as Powderfreak mentioned.
This storm was already our largest synoptic system of the season by noontime, and it was threatening to become the largest system altogether if it could beat out the 23.4-inch event from early December. Well, it cruised right on past that and is now the largest snowfall of the season here.
Also of note was that at the 6:00 P.M. observations, the snow depth at our back yard stake came in at 40.5 inches. We have only been here since ’06-’07, but that is the highest I’ve seen here. We’ve been at 37 inches a couple of times before, but not above 40 inches. The report is in from the Mt. Mansfield Stake this evening, and the snowpack depth there is now 90 inches after this event.
This storm gave ’10-’11 the shot in the arm that it really needed to catch up to the ’07-’08 and ’08-’09 La Nińa seasons. It has now cruised right past ’08-’09, and is within an inch of where ’07-’08 was (179.3 inches) on this date
I’ve added the latest storm totals I’ve seen from some of the Vermont ski areas that have updated this evening, and some are approaching the 3-foot mark. The areas are listed north to south:
Jay Peak: 34”
Smuggler’s Notch: 30”
Bolton Valley: 32”
Mad River Glen: 30”
Mount Snow: 0”
Some details from the 6:00 P.M. observations are below:
New Snow: 2.5 inches
New Liquid: 0.10 inches
Snow/Water Ratio: 25.0
Snow Density: 4.0% H2O
Temperature: 20.3 F
Sky: Light Snow/Flurries
Snow at the stake: 40.5 inches
While this season has been more consistent than average in terms of winter temperatures around here, it has seemed pretty average in terms of snowfall and liquid because we went so long without any synoptic storms. I’d say with this storm though, we may have stepped into above average territory. As of this evening, the snowpack at the stake on Mt. Mansfield hit 90 inches, which is certainly above average. Below I’ve listed some of season to date snowfall numbers for resorts around here:
Jay Peak: 299”
Bolton Valley: 287”
Mad River Glen: 247”
The snowfall numbers don’t seem outrageous for the Northern resorts based on their seasonal snowfall averages, so I think it’s going to take a big March if snowfall is going to end up substantially above average around here. Chances may be incoming - after a couple of clear days to ski the new snow, the NWS says that there are more storms lined up starting on Thursday.
Tuesday, March 8th, 2011
From Powderfreak over in the Northern New England thread at Americanwx.com I noticed that some of the areas updated their totals this morning, so I’ve added them below:
Jay Peak: 42”
Smuggler’s Notch: 30”
Bolton Valley: 32”
Mad River Glen: 32”
Mount Snow: 0”
On their website, Jay Peak noted that this storm set a 24-hour record for them with 32 inches falling between 1:30 P.M. on Sunday and 1:29 P.M. Monday, although in the Northern New England thread it sounds like there could be some contention with their numbers.
Below I’ve listed updated season to date snowfall numbers for some of the resorts:
Wednesday, March 09, 2011
Some pics... awesome day in NNE.
Thanks for all the great pictures Scott, absolutely agree about the day. Started off clear and cold with single digits, and went right into clear and warm at around 30 F. I was up skiing with Dylan at Stowe yesterday and it was a great one to be out.
BTV has their storm total summary out, and I hadn't seen it posted yet so I've added it below. The highest listing on there for snowfall is 3 SW Jay at 34.0", and for snowpack it’s Mt. Mansfield at 90.0” of course, but there is also Jay Peak at 78.0”, then 4 N Walden at 49.0”. In our neck of the woods in Washington County we’re 3 NW Waterbury, and it looks like there were several Waterbury sites right in that 2-foot accumulation range like us. It is interesting to note that the other two Waterbury sites listed in the snowpack section of the table, which are both NE of town, had notably lower values for snowpack. Those spots would be much more removed from the spine, so I’m sure our location gets a lot more upslope snow, but as we discussed earlier in one of the threads, that doesn’t really amount to much in terms of snowpack building. The discrepancy certainly wasn’t from this synoptic event with those sites receiving 22.2” and 24.2” of snow, so it must have been in the past with another event or it could have been during consolidation during one of the warm spells.
Some big snowpack out there... here's BTV's "snow on ground" listing.
LOL, looks like you posted that while I wasn't looking, but I threw in the whole snowfall/snowpack table and image from BTV, seemed like a good one to have in the archives (hopefully American won't go the same way Eastern went - is there any way to access all that data from before?). I'm wondering if BTV can reconfigure their snow total graphic to have a slightly higher scale that discriminates beyond 24 inches. It would be nice to see where some of the top end amounts were localized, but with this event especially the northern part of the state is almost entirely in the 24"+ color.