Friday, March 29, 2013

Winter retreating but ready for a finale during the first week of April

Spring has been creeping its way into northern New England. Even the high elevations have seen extended stretches of above freezing temperatures during the day time in spite of some new snow. The UVM Mt Mansfield snow stake site is showing above normal snowpack as of now thanks to the late season powder surge. The average snow depth on Mt Mansfield, according to the site would suggest that snow depths typically peak around this week before beginning the long spring decline.

http://www.uvm.edu/~empact/data/gendateplot.php3?table=SummitStation&title=Mount+Mansfield+Summit+Station&xskip=7&xparam=Date&yparam=Depth&year%5B%5D=2012&width=800&height=600&smooth=0&csv=0&totals=0

Winter however is still not done. Saturday should feature some exceptional early spring weather. Sunshine will help bring temperatures from the low 20's to the 40's and the visibility should be fantastic. Sunday will likely start out this way as well, but clouds will advance into the state quickly ahead of an approaching weather system. Precipitation will arrive during the evening and in the low lying areas, I think temperatures will be too warm to support any snowfall. Above 2,500 feet, a period of wet snowfall can be expected and the high elevations above 3,000 feet could receive a few inches by Monday morning. It will be a bit sloppy however as opposed to fluffy since much of Monday will feature above freezing temperatures and perhaps some limited sun. The late Sunday early Monday snowfall was not what I was referring to regarding winter not being done. The blocking is going to produce one more big blast of arctic cold and this one, will be rather impressive for early April. The front will arrive during the evening Monday and send temperaturs plummeting well below freezing by Tuesday morning. Only limited precipitation is expected with this arctic front, but there are indications that the boundary will become anafrontal, which means precipitation falls following its passage as opposed to prior to its passage. This would mean some new snowfall Monday night into Tuesday and this snowfall would be more of the powdery variety. Temperatures Tuesday through Thursday morning will also remain below freezing on the mountain which should ensure that the season is extended through the first full weekend of the month. Snow accumulations should remain on the lighter side ranging between 2 and 5 inches but there remains some uncertainty here so expectations might get some tweaking in the coming days.

The blocking which has driven the pattern through much of March is expected to subside and there are some strong indications of much warmer temperatures throughout much of eastern North America beginning April 7th or April 8th. Temperatures on the mountain will actually begin modifying by Thursday afternoon, April 4th but could turn above normal by the 7th and turn well above normal by the 8th or 9th of the month. This is the type of pattern change that could launch the region into spring rather abruptly and have some obvious impacts on skiing by the middle of April. Barring a change, the blog will likely be updated 1 or 2 more times before a final summary.


Sunday, March 24, 2013

Winter continues through the end of March and beyond

No surprise that the late winter storm impacting portions of the Mid-Atlantic will remain south of the region. Portions of southern New England will get some wet snowfall Monday night before the storm proceeds out into the open Atlantic. But, the exiting weather system will still have to contend with the blocked up weather pattern which will make it difficult for storms to proceed east of the Canadian Maritimes. This system will actually get stuck during the middle of the week and allow some moisture to rotate back into interior New England late Wednesday into Thursday. We are late in the winter season now and temperatures this week will reflect that. Overnights, will be well below freezing on the mountain but temperatures on Monday and Tuesday afternoon will approach 40 at the base. Clouds and precipitation Wednesday might hold temperatures closer to freezing but valley locations could simply see some rain while the high elevations sees some accumulating snow by Thursday morning. Dry weather then prevails later Thursday through the last weekend in March. We could see a series of really nice weather days starting Friday and persisting through the weekend with sunshine and some comfortable afternoons consisting of 40-plus temperatures. Not enough to dent the snowpack too much but certainly fleece-only weather.

April is right around the corner and the MRG season hinges on whether we can avoid a major meltdown. The last few cycles of models and ensembles have essentially suggested that the region remains in the grasp of some relative chill through about April 5th. Within this stretch beginning April Fools Day, the mountain could see some more rain or snow or more likely both. The blocking which has anchored the weather pattern should continue through the next week and then weaken somewhat. By April 5th there are indications that the Ohio Valley and Mid-Atlantic will finally see some significantly warmer temperatures but whether or not this warmth makes it to interior New England remains a question

Wednesday, March 20, 2013

What a difference a year makes !

Its the last half of March, but Mad River Glen has finally found glory and certainly the best skiing since 2011. This storm was finally one that belonged to us. Snowfall was the best across interior sections of New England stretching from the Green Mountains of Vermont through much of Maine. The mountain should see a bit more in the way of sunshine and a bit less in the way of snow showers Thursday but a final impulse associated with this system should rotate through during the day Friday, a day which could feature an additional 2-5 inches of snow. This snow, if it comes, might actually help Saturday's ski day more than Friday's but its close. Temperatures will remain below freezing through Friday but might creep above freezing Saturday and Sunday afternoons.

We seem to have found a bit of mojo which would suggest that the Sunday/Monday weather system will actually move north and deliver more snow to the mountain early next week. So far there isn't much evidence suggesting this and we should still expect that the strong blocking wins out and keeps the storminess confined to the Mid-Atlantic. If there are indications of a change, twitter will be alive with the details over the coming days.

For the most part I think next week is free of any impacts from organized weather systems. Temperatures will be similar to what we will see this weekend, well below freezing during the nights but a few degrees above freezing during the day thanks to that strong late March sunshine. There are hints that some energy could get caught up under the Hudson Strait block and thus allow some moisture to rotate backwards into the Green Mountains re-invigorating the terrain-induced snow machine. Climatologically, March is a much more unstable period thanks to the higher sun angle. With the right jet stream configuration, daytime heating can actually allow snow showers to enhance over the higher terrain and we may see a little bit of that next week. There are hints of a bigger organized system around April Fools Day but there are also hints of some milder spring-like weather in the days to follow. If your keeping score at home however, the current March is running 12-14 degrees below March of 2012. March 21st and 22nd of 2012 were the days where many locations saw all-time record temperatures for March. What a difference a year makes !

Monday, March 18, 2013

Can we get 3 powder days out of this by Friday ? Certainly

The March Mad River Glen powder machine has kicked into high gear and our current weather system should deliver its goods as expected. The weather system is a conglomeration of low pressure centers with one delivering snow while losing steam in the Upper Midwest and our developing east coast system which has all the moisture but is a bit less organized. An initial area of snow is expected to move over the mountain Monday night, dump 2-4 inches of snow prior to first tracks time Tuesday but then weaken just as the mountain opens. Do not be surprised early Tuesday to see some very unimpressive radar imagery and reports of only light snow for a period during the mid to late morning. This will happen because as of early Tuesday, we will still lack a clearly defined low pressure center and areas of precipitation will lack any organization or concentration. As the day progresses this will change as the storm will gather a little strength in eastern New England and allow precipitation to enhance over the central and northern Green Mountains late in the day. After mostly light snow during the ski day, snow should begin to fall more heavily toward the mid and late afternoon and into the evening. Most of our 10-15 inches should fall in the window between 2 pm and about 10 pm Tuesday with light snow before and after this period. Winds will be out of the due east Tuesday and could be a little blustery at the summits but will shift to the west Wednesday and be a bit tamer at the summits. 

The four day period ending Friday could see snow totals exceed 20 inches thanks to a pool of instability from that old and decaying Upper Midwest snow producing system. This area will be slow to move east and the best area for the additional snow might be north of MRG. Still periods of snow at varying rates, particularly Wednesday and Wednesday night and then again on Friday could slowly add to Tuesday's totals. In essence this upcoming period is capable of delivering 3 or perhaps even 4 powder days. Tuesday's snow will be denser, perhaps a little on the wetter side at the base (powder above 2,500 feet) but whatever falls Wednesday through Friday will be lighter, fluffier and all powder. The "additional snow" part of the forecast has some question marks. Snow of the terrain enhanced variety is always tough to nail down but there is also a disturbance rotating through the deep east coast upper trough which is expected to spawn a weak coastal snow producer Thursday. This system will have no impact on MRG except that it could rob some of the dynamics that might help get us that 3rd and 4th powder day Thursday and Friday. I'll keep an eye on this as we progress but this situation is totally capable of delivering 3 powder days to the mountain before its all over by the weekend. 

Models continue to gradually provide a little more clarity involving what could amount to a respectable Mid-Atlantic storm late Sunday into Monday. With the AO being as negative as it is, it will be hard for the mountain to get much love from this but March is known for a few curveballs and it will need to be watched. I will never forget early March of 2001, another period featuring a big high latitude blocking feature and another period featuring a big east coast storm This storm was expected to be historic for the  I 95 corridor while the forecast called for partly cloudy for Mad River Glen, Stowe and Jay Peak. What happened instead was rain along the east coast and 50-70 inches for those three mountains. 

Friday, March 15, 2013

Nice looking snow producer looking more likely Tuesday

Terrain enhanced snow finally found its way to the mountain Thursday and the result was some surprising snow totals Thursday. There are many years where the combination of a little instability and low level moisture will result big powder days for the high elevations of VT. We have had so little of it this year that I have been somewhat afraid to predict it, but the Thursday fluff proves that the Green Mountains can still bring it under the right circumstances. The nearly 10 inches Thursday combined with the bit of snow Friday evening has MRG back in the winter spirit. And best of all more is on the way.

No new snow for the weekend as very cold, very dry  high pressure builds over New England. The airmass is capable of sending temperatures back toward zero, perhaps even below zero Sunday and Monday mornings. Most importantly though, the airmass will be an important building block in establishing a healthy overrunning surface for our upcoming winter storm Monday night into Tuesday. The weather system will be a conglomerate of low pressure centers with one moist storm moving out over the southern plains Sunday while another brings now and wind to the Dakotas and Minnesota at the same time. The storms are not likely to phase and the southern stream system is expected to strengthen and eventually prove to be the prevailing precipitation producer along the east coast. There is some dissension amongst the models regarding the amount of mid level warm air that gets thrusted into the state as the aforementioned storm approaches. The European model has had a more consistent handling of this evolution and is thus the favored solution as of now which is good news for us. Snow should develop Monday night, continue into Tuesday and within this period of snow should be a burst of very heavy snow since this is one of the more moist systems to impact the region this year. Snow totals could be around a foot by later Tuesday and some additional snowfall is possible from instability associated with the lagging decaying low pressure center Wednesday and Thursday. In short, it will be a very wintry week in Vermont and should be one of the best of the season at MRG.

The blocking is still the main driver of the pattern. Interestingly it is not the NAO or PNA but larger scale AO (Arctic Oscillation) which will be off the charts in the negative direction during the last 10 days of the month. This is what we saw in 2010 and this will certainly act to thwart any major thaws through the end of the month. In 2010 however we did see a very suppressed jet stream as a result of the strong blocking and we should see this again. March is a quirky month so you never now whats going to pop up on the forecast radar but my guess is that see a relatively dry 10 days following the snow in the middle of next week. The storm I had mentioned that could threaten the east coast around March 24th will have some difficulty moving up the coast.


Wednesday, March 13, 2013

Clipper brings its snow further south this weekend but we are cold and hopefully snowy next week

It's imperative that I pay my respects to what was the most dynamically perfect winter storm of my lifetime on its 20-year anniversary. The March 13th, 1993 superstorm was meteorologically beautiful because it phased a moist and active southern branch of the jet stream with an amplifying and cold polar   jet, and did so historically. In the 20 years since, I have yet to see a winter storm with that kind of "yin and yang". Vermont and Mad River Glen in particular got a healthy dose of the March 13, 1993 superstorm, receiving over 2 feet of dense powder. More importantly,  the "93 Superstorm" was embedded in one of the great periods of weather for interior New England. Basically, the stretch beginning in February of 1993 and persisting through all of the winter of 1993 -1994 featured consistent cold and a ton of snow. On a weekly basis, the state was talking about big winter storms and 1-2 foot snowfalls. It was a great time to be a skier and not such a good time to be stuck in high school like me.

 March 13, 1993

Mad River Glen has not been in one of those epic stretches through the last two seasons. This season tops last and has not deviated from some of the pre-season expectations. That being said, MRG has not been in the most favored locations for big snow but has been the center of the numerous thaws that have interrupted what could have been a decent season. The weekend clipper appears to be another such example. I spoke cautiously about it two days ago simply because our luck with these systems has hardly been optimal. Indeed, the consensus of data has shifted the track of this system south and confines snowfall to southern New England. If the expectations hold, any snow this weekend will be very light and accumulations will be minimal. In spite of this, the weather looks quite cold, unusually cold in fact, through the weekend. A very strong late season arctic air mass is poised to invade New England late Saturday and this follows some garden variety chill which will prevail from Thursday through Saturday. Temperatures over the next 8-10 days will struggle to make it above freezing if at all which by mid to late March is actually quite an accomplishment. Some minimal snowfall can be expected through Thursday, perhaps an inch or two Saturday but that is about it.

On to next week when I continue to hold out hope for a 2013 version of the superstorm. Realistically, a 1993 style phase is going to be pretty tough in next week's set up. Still, we have a healthy looking storm and some very cold air to work with and thus the chances for substantial amounts of new snow are pretty good. Models are currently moving energy out of the Rockies in two waves and are indicating a classic east coast cold air damming signature. If this occurs, the mountain has a chance to get snow from both waves but would get more from the second system Tuesday. It is possible that the models are wrong in their "two wave" theory and the storms energy is more consolidated and this would change the equation somewhat. In either case, the Tuesday system, like many of the others this season might go through an early maturation process and though we have fared decently from these types of system, the results are a big short of historic.

The "cold" part of the forecast looks much more certain and it results from what will be a very favorable blocking scheme. The "block" has been and will be centered over the Hudson and Davis Straits (a favorite location this year) and this favors the best snow and the most anomalous cold toward the center of the country southward to the Gulf Coast. Next week however should consist of a healthy battle of spring-time warmth and some big time winter chill. It will certainly be cold across New England but we want the snow to go with it. We have another chance for a storm around the 24 of the month and we might soon be able to extend the forecast of "relative chill" through the end of March.

Monday, March 11, 2013

Yeah its warm and rainy, but winter ain't done

After a bit of a hiatus, I am back. Long breaks from blogging can either mean bad news that I would choose not to report or I was simply too busy. Fortunately in this case it's the latter, even though our once thought to be storm turned out be a dud and Tuesday's weather consists of rain and above-freezing temperatures. After the rain however, winter will make a quick return. We will see some terrain enhanced snow showers return to MRG beginning Wednesday and this activity will enhance Wednesday night into early Thursday. We probably won't see much from the snow showers, maybe a light accumulation of a few inches but I suspect this will not be the end of the snow. 

There are essentially two decent shots of accumulating snow over the next 10 days or so. The first comes from a clipper system, a potent one actually, that will quickly track across the northern tier of the U.S. Friday into Saturday. Snowfall from clippers hinge on the track of these often quick moving systems. Often times it is a narrow area of decent snowfall but if the storm tracks through the central Great Lakes into southern New England Saturday as current model guidance suggests, Mad River Glen and the surrounding Green Mountains will be in the sweet spot for what could be a nice Saturday 4-8 inch fluffy snowfall. A 100-mile change in the expected track of this system could of course change the snowfall outcome. In the meantime temperatures will for the most part remain below freezing through the weekend starting Wednesday. 

The weather next week could be worthy of much more discussion and speculation. The weekend clipper will bring a potentially strong shot of March arctic chill into New England and this airmass will be firmly in place in front of a powerful storm system that will approach early next week. This storm will begin its track across the country over the Pacific Northwest, dive into the southern Rockies and then track from there into the Midwest by Monday the 18th. Uncertainty relates to how the storm will progress from that point and where it is in its maturation. There are many fine looking ingredients however for a big post St Patty's day dump. We have had a few such chances this year with a few panning out and others falling flat. We have to look at next week as another such chance but a good one as of now. 

Thursday, March 7, 2013

Still waiting for next week to get sorted out but I have yet to have any good news to report

Portions of southeastern New England will see more significant snow from what appears to be a "Norlun Trough" Friday. Admittedly I am not too familiar with the term but NWS employee friends have clued me in on the lingo and Matt Noyes has a very good explanation of the phenomena on his website (www.mattnoyes.net). The coastal system continues to churn off shore and away from the region. We were never expected to get much from this and it proved for the most part to be a big tease and nothing more. Telefest however should consist of some excellent weather. Both Saturday and Sunday should feature above-freezing daytime temperatures and both days will be dry with great visibility. Saturday should be the sunnier of the two days.

The weather situation I was more enthused about was the storm or series of storms next week in the Monday to Wednesday time frame.  The right ingredients seem to be on the table for "something" being that we have an energized southern branch of the jet stream, some incoming cold air by late Tuesday or Wednesday and a block in the upper air pattern to our north. Ensembles have been keying in on this time frame, particularly the European Ensembles, for some time. In the last update I had indicated the lack of hard evidence to support any big snowfall in spite of all the hype I had injected into the prognostication. As of now this continues to be the case. We have yet to see indications of a critical phase between at least a piece of the southern branch energy and any incoming cold. Warm air is in fact  indicated to envelop much of interior New England by early next week, enough to allow for an initial period of rain Monday. Thereafter, much of the energy in the southern branch will move to the coast as the northern branch of the jet begins to usher in colder temperatures to the Great Lakes and New England. How the two impulses interact with one another depends on timing and models continue to struggle to sort it out. The initial period of rain Monday could simply be followed by colder temperatures later Tuesday into Wednesday along with a few inconsequential snow showers. Or, the initial period of rain Monday could be followed by an additional period of rain Tuesday or Tuesday night. Or, the initial period of rain Monday could be followed by some significant snowfall in the middle part of the week. I don't want to completely kill that possibility yet though models seem to have declared it dead if your keeping score at home.

That end of next week through St Patrick's day weekend should consist of normal or below normal temperatures. Although the southern branch appears dormant again after the early part of next week, there are indications of clipper systems and at least some limited amounts of new snow from that. The blocking that is anchoring the pattern is expected to continue through the next 10 days and then weaken. As of now however, there are still no indications of a major March thaw though I would expect the chances will increase (not a bold prediction) after March 20th.


Wednesday, March 6, 2013

Big coastal tries to bring us a little taste

Just a quick update regarding the intensifying coastal system near the Virginia Tidewater. It will track mainly east and out over the ocean as expected, a few hundred miles south of Cape Cod. It will do so slowly however and even though conventional wisdom would suggest this is a complete miss, it might grace the mountain with a brief period do snow Thursday night or Friday and then again it might not. Coastal New England will indeed get better taste of this storm as its area of moisture and wind field spread outward allowing cities like Boston and Providence to get several inches. As of now the best we can do is probably an inch or two.

I continue to think the early to midweek period next week has much more potential. This next storm will try and take the St Lawrence highway and thus might bring a surge of warmth and rain with it. The warm weather and the rain is certainly possible for a time at least initially but the blocking structure in the jet stream to our north should force this storm southward and perhaps trap it over the maritimes creating a situation very conducive for snow. In the spirit of fairness, there has yet to be overwhelming evidence for big snow next week save perhaps the overnight run of the American model, but I do like the set up and think some sort of rain to significant snow event is possible. I'll have more on this in the days ahead of course .

Sunday, March 3, 2013

Mostly dry this week and some storm potential for next week

The storm that will have everyone's attention this week is a big one and will certainly cause its share of travel headaches. Unfortunately the storm is not expected to have an impact on northern New England. The storm will become better organized over the Ohio Valley Tuesday and a simple look at the radar at that time would have us thinking we are lined up for glory. This particular pattern however is anchored by a 2010-style block over the Hudson and Davis strait. A jet stream block of this magnitude has profound ramifications on the storm track and this will be no exception. The storm will ultimately become a ferocious coastal system near the Virginia Tidewater causing snow and wind in the Mid Atlantic that could both shut down travel and result in power outages. Recent runs of the American model have shown a minimal impact for Vermont and a significant impact for portions of coastal New England but I think this is a stretch. Most of the snow with this storm should be south of NYC as the storm will be forced out to sea well before making that key northward turn.

This week's miss will leave us dry and many days should feature decent amounts of sunshine. The strong March sun should power temperatures past the freezing mark for a few hours during afternoons at least at the low elevations but low dewpoints and low overnight temperatures should prevent the mountain from losing significant amounts of snow. Warmer temps are expected Friday and Saturday where readings should push into the 40's but we don't expect rain or strong winds and overnights should continue to stay above freezing. The European Ensembles in particular have shown strong indications of our next big storm early next week around the time of the 11th and 12th. The various operational models have been all over the place and there has yet to be any consistency in the simulations from model to model or run to run. March weather is notorious for being difficult to project in the longer range. From my vantage point, the situation has some promise but there could be limited available cold air when precipitation commences. Ultimately however we should see some accumulation from this by the middle of next week and the questions should have to do with how much.

Through the middle of March there remains strong evidence that blocking over the Davis Strait will be driving our train. We should continue to see some above-freezing days but I doubt we see a major melt down through St Patty's day weekend.



Friday, March 1, 2013

Not done yet !!

Thursday was a bit quieter on the precipitation side and a little warmer than I had anticipated but this game is not over yet. The weakened area of low pressure responsible for our snow will drift offshore  Friday combine with another storm and get throttled westward over the weekend thanks to the giant block over the Hudson Strait. Although we could get a few inches from snow showers Friday, additional moisture will come at us from the top and down the spine of the Green Mountains both Saturday and Sunday. Temperatures will remain above freezing in many valley locations during the day (it is March now) but we should see readings remain generally below freezing from the mid-mountain to the summit. Bursts of snow, when they come, will help keep temperatures in the 20's where it's elevated. When can we expect the most additional snow ? There is loose consensus that the biggest burst occurs late in the day Saturday leading us to a powdery Sunday but I would expect some new snow Friday and Sunday as well. Total accumulations for the upcoming 3-day period will likely be a wide range with a few inches at the base and as much as 10 inches on the summit.

Further out in the forecast period there are a few adjustments although I think the general themes remain. The pattern, through mid-month is anchored by a very favorable blocking configuration ensuring no major early March melt-downs. There is the potential for a big storm in the middle of the upcoming week but the blocking is so strong (what is this 2010 ?) that the jet stream will force this potentially strong winter storm into the Mid-Atlantic where there is the potential for some big snow. In the meantime, MRG will stay high and dry once the snow showers subside on Monday. Much of the week will feature sunshine with cold mornings and tolerable afternoons. The adjustments I had mentioned have to do with the period between the 8th and the 13th of March. In the last post, the blog mentioned the potential for a storm around the 9th or 10th of the month, basically next weekend. The ensembles seem to be keying in on a short-lived warm-up in this time frame as of now. The warm spell could mean temperatures reach as high as 50 for a day but this is nothing unusual. The pattern is still expected to ultimately become highly amplified around the 11th of March and there are strong hints of a significant storm on that day or the day after, one that could produce more significant snow. I'll have more later this weekend but the fun should continue I am happy to report.