Think Snow, Tweet Snow !!!

Friday, February 28, 2014

Another potential VT storm bites the dust as very cold, and mostly dry weather expected to prevail through March 5th

Absoutely, positively, no love from the models late yesterday or today. This after a Thursday where we underperformed on snow squalls, struggling to receive an inch at MRG while low lying valley locations such as Albany seemed to fair better. Needless to say, this put a double sour taste in my mouth this morning and thus the update today is somewhat of a microcosm of the season. Amazing how many things in life work that way. Remember how the Red Sox epic choke of 2011 culminated. They proceeded to blow a late inning lead while Tampa Bay rallied to win and reshape the playoff picture on the last day of the season. It was as if the whole thing was scripted (you almost knew what would happen before it happened !). The weather picture for the upcoming weekend reminds me of that. No, it hasn't been a terrible season, as a whole it still could end up being better than the last two. But states such as Michigan, Ohio, Pennsylvania, New Jersey and most of southern New England are at 200-400 percent of normal snowfall. Much of Vermont is still below normal and in spite of brutal and persistent cold over the last month, the Mt Mansfield snow stake remains below average. It seems totally devoid of fortune, a wordy phrase for "unlucky".

We are fairly accustomed to the cold weather so the mid 20's Saturday afternoon and little wind will almost feel tropical. The day as a whole is still way below average and comes on the heels of an incredibly anomalous Friday where temperatures were nearly 20 below average on the mountain. Clouds will be on the increase later Saturday and some snow Saturday night could total 2-4 inches by Sunday morning.  There is so much precipitation across the country this weekend and early next week, but the 2-4 inches is the grand total for the mountain through the middle of next week. This is a pathetic outcome to be perfectly blunt; but like I said, very consistent with the behavior of the whole winter. When we've been locked into cold thanks to these very powerful PV events, storms become overwhelmed by the polar jet and often suppressed southward. As it stands late Friday, even southern New England is in danger of missing the best of the Sunday/Monday storm which promises to bring more heavy snow to Pennsylvania, New Jersey, Maryland and northern Virginia. Meanwhile, arctic cold will reestablish its grip on the mountain Sunday and keep daytime temperatures in the teens once again. Interior New England will actually be ground zero for the next major outbreak of cold which will be caused by a powerful arctic surface high pressure center which will gradually build over the state early this upcoming week. Temperatures Monday, Tuesday and Wednesday mornings will be in the -10 to -20 degree range and since this is early March, these readings will be perilously close to the lowest in "recorded" history. I have always hated the term "record low" or "record high" since "recorded" history and real history only differs by only about 4.54 billion years. In other words, I am sure these things have happened before !

The strong arctic high will actually remain in control of the weather through the end of the week but will lose its ferocity by Thursday afternoon. There have been hints of some overrunning snow late in the week, a plausible outcome in any warm advection scenario. As mentioned, there is a stronger southern branch storm that should evolve into a full fledged coastal storm for the southeast U.S. coastline. Unfortunately, this storm is entirely disconnected from the jet during this time frame and will receive no additional support from the receding polar jet. The storm is thus expected to drift out to sea causing little snow for anyone.

The weekend of the 8th and 9th looks as if it could finish interestingly with another and briefer pattern amplification expected. Temperatures during the weekend could, for at least part of the time, climb above freezing but not by much. As this is happening a storm may or may not gather strength in the nations mid-section and move toward the east coast. Yes, there have been some hints at something big along the U.S. northeast coast line Sunday March 9th into Monday March 10th but I am not feeling optimistic today. General pessimism and low expectations could prove to be our best weapon against future disappointment. Quite honestly that is a lousy attitude but I am going for a the "kiss of death" in reverse.

Tuesday, February 25, 2014

Cold ? Yes. Snow ? Yes. Deep snow ? Maybe

The "Mad River Glen" homepage suggests I am calling for 3-7 inches of snow Wednesday. Such a forecast should earn me a citation for "wishcasting", a term coined by the nerdiest faction of the Meteorology community and reserved for those that forecast what they want to happen as opposed to what is likely to happen. I did actually predict 3-7 inches of snow in the last update Sunday evening, but it was over a two day period beginning Wednesday ending Thursday. The snow comes from two separate clipper systems and most of that should fall late Thursday from the latter. Wednesday's clipper appears almost completely devoid of moisture but the mountain could get an inch, maybe two at the summit from what could be a brief burst of snow during the morning. Thursday's clipper isn't particularly rich on moisture either, but this is a much more dynamic system. Some early sunshine and sub-zero temps will give way to clouds and eventually some snow showers. There is a fairly decent layer of instability associated with this clipper so some snow squalls are likely. The high country should do the best with upwards of 5 inches north of Stowe and 2-4 inches at MRG. I am very impressed with the cold weather, not only over the next few days but over the next 7-10 days. It's one thing to have temperatures in the single numbers during the day during January but quite another to see 36-48 hours of sub-10 degree readings in late February or early March (where high temperatures even on the mountain actually get close to freezing). It looks like we could see multiple such stretches and very few opportunities through March 10 for any melt.

Beyond Thursday there is about a 3-day battle between the bitterly cold arctic air brought on by the most recent PV attack and a temporary upper ridge that will establish itself near the southeast U.S. coastline. There will be strong temperature boundary or front that will stretch from the southern plains to the Atlantic Coast, waffling up and down the coast in fact around passing low pressure centers of varying intensities. The waves of low pressure, and there will be at least two, should bring the chance for several periods of snow. The big question involves what area sees the best snow and how much falls. Light snow from this setup should begin Saturday and continue into at least part of the day Sunday before arctic cold reestablishes a firmer grip on interior New England. What should be the last wave in this series is the potential storm we have been discussing for almost a week. This storm has the most potential as far as snowfall totals go but the track remains uncertain. It looked up until this morning that we were establishing some consensus for a decent hit Monday 3/3 into early Tuesday 3/4 but the midday cycle of models Tuesday took everything farther south and showed something less than a decent hit. There is a lot on the proverbial playing field, but in the end we should see at least a few inches of snow this weekend into early next week and hopefully quite a bit more.

The end of next week appears drier but lingering energy in the southern branch will try and brew up a coastal storm. This is long shot but at least its another shot. Cold weather remains in a big way with high temperatures in the teens or twenties and maybe even lower for a day incredibly. Around the time of March 9th or 10th, we could see some more snow from at least a semi-organized system.

Sunday, February 23, 2014

Polar Vortex bringing lots of cold over the coming week but it's also hurting our new snow potential

No more melting of our hard-earned snow until we are well into March i am happy to report. We still do need the powder though, as we would after any rain event. Instability remains in the lower troposphere through Monday but we are too dry for significant snow, just flurries and lighter snow showers. Meanwhile, it is portions of southern New England again that are the first to get re-whitened following the thaw.

The big story for the upcoming week in many places is Polar Vortex round ??? I think it is 5, but I might have lost count. I still can't get over how the term has become so ingrained in the American social consciousness, I thought such terms were reserved for special geeky enclaves such as the SCWB. But I digress, we know from our PV experiences that we get cold in these types of instances and we also know that the jet stream gets revved up and can both suppresses and overpower many of our would be storm systems. The southern branch of the jet stream is not entirely dead during the upcoming week but it will have to compete with energy from the PV, a challenging undertaking.

The first real piece of southern branch energy that is worth watching is an impulse that will track over the southern states Tuesday and advance up the Atlantic coast Wednesday. Incoming energy from the southward dropping PV and the relative warmth of the ocean will help fuel this storm, but it will be somewhat tough for this system to make that critical northward turn although it will try. Snow should be able to advance at least into southern New England and a well-timed clipper might help suck some of this moisture northward into interior New England for a period of light and fluffy snow Wednesday. On the heels of this system will come a quick moving clipper system rotating through the PV Thursday. This should keep the snow flying for a 2nd straight day but in both cases the snow is not expected to be too significant, amounting to 3-7 inches over the two days. The Tuesday to Friday stretch will be characterized more by the unusual late February cold as readings will mainly be in the teens during the day and below zero on Wednesday, Thursday and Friday mornings. This is typically the period in the season where any sunshine can boost temperatures close to the freezing mark or beyond, so relative to normal this upcoming period will be very cold.

The pattern still seems on track to produce more active weather thanks to the combination of split flow in the jet stream across western North American and the eastern Pacific along with the receding PV. The first byproduct of this pattern may come over the first weekend in March with the southern branch producing what could be a coastal system. At this point in time, the PV might be too close to allow such a storm to get too much traction before getting guided out over the ocean. Many of these storms in these instances are getting blown away by fast balls when they encounter jet energy associated with these PV's. The storm I had mentioned for the last two updates in the period between March 3-5 will arrive after the PV recedes somewhat and I still think it is this storm that has the best potential to yield results.

No sign of an extended period of warmer temperatures in early March. The pattern will relax somewhat toward the end of the first week in March but ensembles are showing another pattern amplification between the 8th and 10th of the month and this promises to bring more cold and snow potential to the mountain.

Thursday, February 20, 2014

Polar Vortex V poised to bring it next week after some minimal melt Friday and early Saturday

Most of the mountain will only see a brief window of rain on Friday and thus this will not be a particularly intense thaw or nearly as bad as the one we experienced back in mid-January. Precipitation could actually arrive as a serious burst of snow or a snow/sleet mixture before changing to freezing rain just before dawn. Ice accumulations could be significant as some of the heaviest precipitation will be occurring right around 7AM Friday with temperatures still expected to be a touch below freezing. Temperature cross sections suggest the icing will the most severe at the summits with very little opportunity for rain at any point in the day. Sometimes these situations become counter intuitive with the more protected valley locations getting the worst of the icing but in this case, the inversion in the atmosphere is shown to be well above the 4,000 feet. Temperatures in the lower sections of the mountain will creep above freezing Friday afternoon and thus the period of rain. All precipitation will end by Friday evening.

Saturday is expected to be a milder day and dry in the morning. Readings will be sub-freezing in the morning but rise well into the 30's by early afternoon thanks to some early day sunshine. Perhaps this is not a bad thing since it will give the snow an additional chance to soften and the water to soak through and run off. There are a couple of weak jet impulses that could bring snow back to the mountain as mentioned 2 days ago. The first arrives late in the day Saturday with snow showers arriving even as temperatures remain above freezing. The scenario is almost analogous to a summer afternoon thunderstorm since warming temperatures Saturday will turn the lower troposphere unstable and allow the development of some convective snow showers. If we are lucky, we could squeeze out a few inches out of a burst of snow. Flurries and lighter snow showers will continue through Sunday with temperatures remaining generally below freezing.

Polar vortex round 5 begins next week. The center of the deep freeze will actually stay in Canada, mostly over Ontario and Quebec but interior New England will be back in the deep freeze as well with temperatures well below zero during the mornings Wednesday through Friday and only in the teens during the afternoons. There are weak weather features early in the week that could bring light snow to the Green Mountains but none look substantial. The southern branch is not completely dead but it will be suppressed south much of next week and a weak area of low pressure is expected to be one product of that early Monday. This storm and its impacts area expected to remain well south of Vermont and the best we can do is probably another round of snow showers or a brief period of lighter snow/.  The next weak weather feature late Tuesday is more of a clipper and may bring a round of light snow to Vermont before bitterly cold temperatures advance into the state Wednesday.

The real active weather begins in March as the PV relaxes and recedes and another round of split flow in the eastern Pacific and western North America emerges. There are signs, even 12 days out, of a major storm in the time frame of March 3-5, the first of what could turn into another very productive period for powder. With much of this thaw mitigated, there is little doubt that we will move into March with a healthy base and additional snows will quickly turn conditions very good.

Tuesday, February 18, 2014

Some snow Wednesday but no avoiding the ice/rain Friday

Arctic cold is very slowly giving ground to milder pacific air, but this very gradual process has already resulted in a few inches of snow Tuesday. On Wednesday we will see an encore performance as a clipper system will gain some last minute steam along the southern New England coast. A week ago this looked like a "spring"day, now it's a powder day. Sort've a powder day I suppose, since snow will actually develop Wednesday afternoon and continue into part of the evening. Temperatures will be considerably milder than early in the week, approaching the freezing mark, but the day will feature snow, another 2-4 inches.

Thursday is still expected to be dry and the late February higher angled sunshine will go to work, sending readings above the freezing mark and likely softening the snow on a good part of the mountain. Lack of wind and great visibility will make it one of the more comfortable days this month. Temperatures will have a brief opportunity to duck under the freezing mark Thursday night ahead "odorous" storm system discussed in the previous update. A strengthening upper ridge across the eastern third of the U.S. will unfortunately guide this storm deep into Canada, ultimately stalling out east of the lower Hudson Bay. A surge of warmer temperatures will thus reach Vermont, but before it does, precipitation is expected to develop across the state and at MRG in the pre-dawn hours Friday morning. Temperatures cross sections make it appear that areas of the state, east of the Green Mountain spine, will see a several hour period of freezing rain Friday morning before precipitation goes to plain rain during the day. I think temperatures might creep into the low 40's briefly Friday but this will not be an extended thaw. The rain will end by Friday evening and temperatures will be back in the 20's Saturday morning.

We had discussed a possible storm over the weekend, an event which could have quickly erased the bad feelings of our Friday rain event. Unfortunately, models have taken a decisive turn against such an occurrence. There are a series of weak upper air impulses between Sunday and Monday which could provide some refreshment. Monday the 24th also looks potentially unstable enough for terrain induced snow showers. We can then look forward to another cold week to finish off the month of February, this thanks to a surging PNA index. Models have hinted at a coastal storm during the middle of the week but Vermont snow is being indicated to be the end result of clipper type systems (this could change). Temperatures, as mentioned will be chilly with high's in the teens and 20's most of the week and low temperatures in the single digits or below zero.

There is evidence of another temperature moderation at the very beginning of March, at least a brief one. If this occurs I think it will be short-lived and I believe more split flow in the jet stream will dominate the early part of the month. This means another round of active weather much like we have seen this month.

Monday, February 17, 2014

Snow prospects look better, while thaw looks brief and less intense

SCWB entries have been full of good news over the last few weeks and it was expected that the positive vibes might end with the current entry. From a certain point of view I suppose that is so, but from my point of view, weather and forecasting is relative. One expects a certain narrative to play out but when the narrative changes our reaction is based on the nature of that change as opposed to the specifics of the story. At least that is the way it works for me. The end of the upcoming week had and to some degree still has a foul stench to it that one could smell even a week ago. Successive cycles of models have rather significantly mitigated much of the odor. One could speculate as to the reasons why this potential ugly thaw doesn't look as bad. My feeling is that there are two major feedbacks working in our favor and should be for the duration of the season. 1) A massive expanse of snow cover over the Midwest and Northeast 2) A remarkable coverage of ice in the Great Lakes. The latter is particularly noteworthy. 4 out of 5 of the Great Lakes are about completely frozen with Lake Ontario being the last hold out. You have to go back at least to 1994 to see anything remotely close to a situation like this. With much of the Great Lakes ice rather than water, the aggregate lake environment does not have the same impact on the weather map that it would in a typical winter. In the end, cold air masses are consistently winning small battles against surges of warmth and over time, these results make a difference.

Over the next week, almost everything on the weather map looks farther south. We are still expecting a dose of  snow from a "fun of the mill" weather system that should spread the powdery stuff into Vermont early Tuesday. This storm marks a division between very cold arctic air and eastward advancing and milder pacific air. In the end we should see 3-6 inches from this period of snow which should end Tuesday evening. Tuesday's temps will mostly be in the teens. Wednesday will be substantially milder, closer to freezing actually but a weaker disturbance will keep clouds in the region and more snow, maybe even an inch or two. Amazing, but a day that looked very much like a very mild day, now could at least partially turn into a powder day. Thursday will dry and above freezing temperatures in the afternoon should finally remind us that March is just around the corner.

What's left of the "odorous" stank occurs Thursday night and Friday. By this point a large upper ridge covering the eastern half of the country will guide a well organized storm system deep into Quebec. Rain or freezing rain should develop Thursday night and we should certainly see a period of all rain Friday, at least a half an inch of the liquid stuff. Temperatures could briefly surge from the 30's Thursday night, all the way to 50 Friday but the mild intrusion will actually be short lived and colder weather will begin displacing this warmth by Friday evening.

Models have been hinting, several times actually, at a storm for the weekend of the 22nd and 23rd. Although the warm ridge gets beaten back late Friday it will not disappear entirely. A storm system will again be guided up the slope of this upper ridge somewhere in the vicinity of New England. A few days ago, this appeared to be the second part of a potentially damaging thaw and perhaps another rain event. Again, in the last few days everything looks farther south and as the jet loosens in the Pacific by the 22nd, cold arctic appears like it wants to make a more efficient southeast advance, perhaps fueled by some of the feedbacks discussed above. If the cold proves to be a significant player in this evolving weekend event, and there is every indication that it will be just that, precipitation from this storm has a much better chance of falling as snow. As of now, models are still having a tough time with this system and whether or not it exists at all. As of now, I am certainly a lot less worried about a 2nd round of rain.

Cold weather fueled by the reemergence of a positive PNA and a loosened jet in the Pacific will likely dominate the back 6 days of February. Beyond the weekend, we could see some more snow from either a passing clipper system or simply from terrain induced snow showers. During the last day or two of February into very early March there are some more signs of splitting in the flow and some resulting active weather.

Friday, February 14, 2014

Bombogenesis II and some additional snow likely for Tuesday

Lots going on and lots more is expected to happen in the coming week and lots of people have plans to be at the mountain in the coming days I am sure. ”Bombogenesis – The Sequel” will indeed happen and although it will not mean another 1-2 feet of snow for the mountain, I expect we get some Saturday. The catalyst is another very potent upper air impulse and a much weaker surface feature. By Saturday morning however, the dynamics in the atmosphere are such that even an initially weaker storm will see explosive development south of Long Island, ultimately deepening again to sub-980 mb northeast of Cape Cod. The track of this system is too far east for big snow across much of VT although much of eastern Mass and all of eastern Maine will get a big taste Saturday night. The explosive development of  this storm will allow for the precipitation shield to expand west into Vermont however, at least the section capable of producing an extended period of lighter snows. Northwest flow later Saturday will also encourage some terrain enhancement and I would expect a few inches Saturday and Saturday evening. 

The door will then swing open for a sneak attack of arctic cold and interior New England will get the brunt of this airmass. Sunday will be a blustery day with more snow flurries. Temperatures will start in the teens but end up in the single digits later in the day. Monday morning, Presidents Day, will feature less wind  and better visibility but readings will be below zero in the morning and struggle into the teens later in the day. 

Our next storm system is looking better and better as far as snow is concerned. This is a warm advection type of event with a front marking the division between arctic and pacific air. The frontogentics in these types of situations can be quite productive for snow and I expect this to bet the case with this very garden variety system on Tuesday. Snow should begin late Monday night or early Tuesday morning and persist though a good chunk of the ski day. I am feeling pretty good about several additional inches. 

Beyond Tuesday lies lots of Pacific air and the milder temperatures.  Readings should inch above the freezing mark Wednesday but I expect 2 days in the 40’s and 1 in the 50’s at the very least between Thursday Feb 20 and Sunday the 23rd. There is likely a rain event of some sort looming in this horizon as well. The warm weather keep the snow soft in that time frame but to keep the snow soft at the end of February we will need some more help. There are signs beyond the 23rd that another positive PNA regime emerges with intrusions of arctic cold that should keep the mountain sub-freezing through the last week of the month and perhaps into early March as well.

Thursday, February 13, 2014

Valentines Day Storm 2014 and all it's goodies

Snowflakes are flying across Vermont so more or less, the party has started. Even as we have inched closer to the event time, high resolution models have struggled with this relatively compact storm. This is understandable since there are some rather intriguing intricacies. Most importantly, it is a narrow area stretching from eastern Pennsylvania, to the Catskills of New York northeastward to the spine of the Green Mountains that should see the best snow. A few days ago this seemed possible with some loose consensus suggesting such, now it seems likely.

The biggest concern I have had and still have relates to the play by play during the storm. Radar imagery as of Thursday afternoon indicates an area of heavy snow moving northeastward through New England, behind that a large dry slot where no precipitation has fallen. This initial batch of snow has been very impressive dumping 3 and even 4 inch an hour snows from eastern PA to much of Mass but the strengthening low pressure responsible for this is moving a bit out in front of the deepening upper air support. This essentially means that MRG and surroundings is in store for an initial burst of snow Thursday afternoon. During the evening and into the early part of the overnight some dry air could get entrained into this initial conveyor of moisture resulting in a several hour period of lighter, less than 1 inch per hour snow. This deepening and very intense and quite closed piece of upper air support will ultimately win the day. Almost like a puppy on a leash, the aforementioned jet stream feature will give our winter storm a yank and prevent it from advancing too far to the northeast. In the end, a much more consolidated low pressure center will explode near the small strip of New Hampshire coastline to sub 980 mb. The associated precipitation shield or snow shield will likewise intensify. Some of the higher resolution simulations in the last 12 hours have really driven this point home. The snowfall intensities in the pre-dawn hours are indicated to be almost historic and in some cases really hard to believe. Take what is indicated and cut it in half and we could still see 2-3 inch an hour snowfall rates for a period of about 3 hours right at or just before dawn Friday. With that said, I am all in for our 15-30 inch storm total with the snow tapering to flurries in the afternoon. 

A couple of other things that should address some emails and other FAQ’s.

1)    I would not be surprised to see a minimal amount of sleet in the overnight hours Friday. There is a small near freezing layer in the lower troposphere that would only be an issue given very light precipitation. Once our bombogenesis is underway early Friday morning, it is all heavy snow all the time. 

2)    Snow consistency should stay of the powdery variety although at least initially, it will be of the denser powdery variety. By Friday morning, the snow should become more fluffy thanks to a more favorable dendrite growth environment in the later hours of this storm. Temperatures will be in the 20’s during most of this event but should stay far enough from 30 to prevent too much in the way of wetness in the snow. 

3)    This is a big one and I might get in trouble for speculating but what the heck. With any “bombogenesis” there will be wind, lots of wind. Vermont will be no exception. Winds are expected to be very strong particularly early Friday. As far as the Single Chair goes the wind holds are primarily associated with a prevailing east wind. The wind will be ferocious, gusting to 50 at the summits but it will be well north of east in direction, primarily north and then northwest later Friday. I am not making any promises and there are probably guys on the mountain that no more than I do about it and if they feel the need to chime in and scold me please do so. 

We also have another weather system Friday that will ultimately track slightly east of Cape Cod. It’s reinforcing area of upper air support however should mean additional snows Saturday, several inches I think. 

Lastly, this should be one of the best weekends at MRG in a few years so please get out there and get some. That being said, stay safe on the roads. The driving Friday morning, particularly early Friday morning, will be awful with low visibility, blowing snow and drifting on the roads. Plan around this if you can and please enjoy.

Wednesday, February 12, 2014

Big time east coast storm may be saving its best shot for Vermont !!

A couple of days away from a reliable internet connection and in that time there was all sorts of rioting amongst forecast models in regards to our late week storm. For once, we have a well organized, maturing southern branch feature, loaded with moisture, poised to move up the eastern seaboard in the  midst of an  amplified jet pattern. The result will be a very intense, yet compact winter storm. Since the east coast media has become hyper-focused on these storms, there has been a lot of opinions, forecast maps and some crazy proclamations all of which  have seemed to change from one day to the next. The expected strong intensity combined with this distinctively compressed personality will make the forecast a challenge particularly along the immediate east coast. For Vermont, however, much of the fogginess in the forecast consensus has cleared and I expect the the best storm of the year, perhaps in 3 years late Thursday into Thursday night.

By Thursday morning, a maturing low pressure center west of Cape Hatteras will spread rain and snow to the Mid-Atlantic and continue tracking toward eastern New England Thursday night. As it does, the storm will continue to deepen, perhaps to 980 mb as it enters the Gulf of Maine early Friday. There will be a very tight corridor of intense snowfall and although some disagreement remains as to what corridor gets this snow, the spine of the Green Mountains is the favored area in my opinion. Snow will begin late in the day Thursday and become very intense during the overnight hours with 2 and 3 inch snowfall rates, and perhaps even some thunder in a few spots. The center of the storm will elongate vertically during the overnight hours and warm, above freezing air will get thrown westward into coastal regions and well into New Hampshire. Low lying areas of Vermont, particularly the Connecticut River valley could see some mixed precipitation, coastal sections of New England will see a change to rain, but the high country of Vermont should just see snow, heavy snow in fact. If the storm wasn't moving at such a brisk clip I would throw out the 2-foot plus forecast but for now lets call it 15-30 by Friday afternoon.

A tightening jet in the Pacific will bring a second yet potent system that will effectively re-amplify the pattern for Saturday. The system will not have much in the way of moisture to work as the core of the upper air impulse moves into West Virginia Friday night; but as it proceeds to the coast, another storm will form and move northeast just off the southern New England coast. The storm will not be strong enough and will not track far enough west for another round of super heavy snow for VT. The large pool of instability associated with this feature however combined with prevailing northwest flow should set the stage of terrain induced snow showers over the mountains. The snow showers should provide a fluffy addition to what should be a very healthy base, perhaps a significant addition of several inches during the day Saturday. Overall the mountain could certainly see one of its beloved 2-3 foot in 3 day type periods, a scenario long overdue for the mountain and well deserved.

Snow showers should continue into Sunday but not quite as intense.  Monday, president's day should feature much more in the way of sunshine and great visibility although it will cold cold with temperatures generally in the teens during much of the ski day. Arctic air will retreat somewhat as next week progresses thanks to this aforementioned tightening of the jet stream in the Pacific. There is however one more weather system that is capable of producing some snowy goodness during the middle of next week. The retreating cold will mean that there is some ice risk with this storm but additional snow is likely, at the very least during that Tuesday/Wednesday time frame.

The risk of a thaw goes way up toward the weekend of the 22nd and 23rd. It looks like a short-lived type of thing but there are plenty of better things to think about right now. Enjoy.

Saturday, February 8, 2014

"Model Hugging Syndrome" and a might be storm late in the upcoming week

I have been getting some comments, tweets, emails asking or referring to a specific model at a specific time. It's actually great to see so much nuts and bolts interest in weather forecasting which I know has existed for some time. That being said, weather enthusiasts and closet weather enthusiasts (me included) can be at times stricken with "model hugging syndrome" or "MHS". The "glass half empty" guy will send me a doom and gloom email regarding some model showing rain while the "glass half full" buy will ask me about some model forecasting a 2 foot storm 10 days out. There is so much model to model variability with the output that "MHS" is capable of sending someone to the loony bin. It didn't help when NCEP decided to run the American GFS model 4 times a day even though concrete upper air data is only collected twice a day. The GFS in particular is chaotic even beyond day 5 and the biases and issues with the model need to be corrected by way of improving the physics in the model as opposed to running it a zillion times a day. This however is not a model bashing rant. In spite of biases and flaws, models are capable of performing a massive amount of atmospheric calculations that humans are incapable of and powder hounds certainly should use them to help plan sick days. These calculations can differ quite greatly however because a models run 6 or 12 or 24 hours can interpret either the same or different rounds of upper air data quite differently. It is thus important to look at a collection of data, try to establish a consensus of what the data is showing, making additional adjustments based on known biases, factor in any observations that models might be failing to account for and finally reach some sort of conclusion as to what might happen. In the end, there are lots of moving parts and it always best to expect these parts to move over time.

The decaying piece of the massive Rocky Mountain storm will approach the region Sunday and spread some light snow into most of Vermont Sunday night. The storm will try and get energized off the New England coast but too little too late I think for a big event. A little event is still welcome though and we could squeeze 2-4 inches out of this by the end of the day Monday which should be blustery and chilly with temperatures in the teens. Tuesday will be crisp and cold with sub zero readings in the morning. It should feel nice by the afternoon however with plenty of sunshine and temperatures inching toward 20 degrees. We should see more of the same for Wednesday only a little warmer and perhaps more high clouds late in the day.

The weather map later in the week consists of a southern branch storm that will intensify and move up the Atlantic Coast while a clipper system slowly approaches from the west. We had hoped these two systems might combine to form a monster noreaster by Friday but this may be a stretch. The southern branch storm however should track close to Cape Cod, it appears to be a more compact event but system is certainly capable of bringing a healthy period of snow to MRG and surroundings Thursday. The clipper then arrives Friday with a nice cool pool or instability pool which should kick the snow shower machine into action later Friday into Saturday. Different models are still producing different results Friday; in fact, there is less consensus Saturday than there was 48 hours ago. Still, we do have some consensus for some decent snow leading up to the weekend 15th and 16th.

Ensembles are still indicating a tightening of the jet in the Pacific beyond the 16th. The region has some tepid support from the AO and NAO but recent ensemble data has shifted the core of coldest and most unsettled weather into the western states. That is not a good trend as of this morning but below freezing temperatures should keep any fallen powder, powdery at least through around the 18th of the month. We have to open the door for the possibility of a thaw in the days that follow that.

Thursday, February 6, 2014

Weekend storm fizzles but another one is on the horizon

One much needed storm is in the bag and I can report first hand that the mountain skied very well today. I can also report first hand that it is always a good day when a blog entry can be done from the MRG bar in the afternoon with a beer in hand. There has been lots of talk about the potential weekend event and when I talk to fellow skiers and riders it seems they all know about it and already know what is going to happen to it. What the heck am I here for then ;)

It does not look as if things are going to come together quite as we would like over the weekend. Southern branch energy in the jet stream will consolidate off the Carolina coast on Saturday (bringing more snow to DC I am sorry to say since they have no appreciation for it) while a weakening storm exits the eastern Rockies. The weakening system is the piece of energy that we had hoped would take the drivers seat but there are too many chefs in the kitchen I suppose to make this happen. Nonetheless, there is some minimal hope with this decaying system. It will make a last ditch effort at intensifying off the New England coast some snowfall is still possible Sunday into Monday as a result (a light accumulation). In the meantime temperatures will stay on the below side of seasonable thus continuing what has become a building stretch of rain and ice free weather. The Sunday/Monday should've been big snow event will mark another intrusion of colder temperatures but we have seen considerably worse than the readings we will see early next week.

The active weather will continue as promised. It was mentioned in the last update that a late next week snow seemed probable and there is rather good clarity of a relatively organized winter storm late next week. The time frame would be Thursday, a week from now which means lots of fine tunings will be necessary. In the forecasting game however, one loves to see ensembles from separate model packages provide this kind of consensus so early. This consensus includes a storm riding up the coast Thursday spreading snow into New England. In the wake of this storm a nice pool of instability should kick the snow shower machine into gear and set up the weekend of the 15th/16th as the best of the year.

Beyond that, the pattern continues to look active. We will see a tightening of the jet stream in the Pacific but as this is happening the Arctic Oscillation  and North Atlantic Oscillation will turn negative helping to anchor the cold in North America while more storm system cross the country. This should mean more snow to talk about.

Monday, February 3, 2014

A nice 6-12 Wednesday, but is the "big one" poised to unleash it's fury on the 9th/10th ?

Our midweek storm is on track and on target. The system will strengthen along the Gulf Coast Tuesday, move into Tennessee Tuesday night and then quickly transfer much of its surface energy to Jersey coast Wednesday. The system will show some initial potential and certainly has the moisture to move from a  "good" to "great" event when the effects of this storm finally reach VT and vicinity. Ultimately however, this will turn out to be a flatter, very garden variety storm for Vermont although a much needed and much appreciated snowfall. The snow will arrive in the pre-dawn hours Wednesday with a period of heavy snow in the early part of the ski day. Once the storm effectively transfers to the coast however, a relatively strong jet stream will guide much of the moisture and energy out over the ocean. Snow intensity will thus lessen later in the day and taper to flurries during the evening. The best upward motion associated with this system will actually be situated in the southern half to two thirds of Vermont and New Hampshire with sleet and ice across Mass and interior Connecticut. Mad River Glen is thus on the northern edge of what I think will be the best snow. Accumulations will likely be in the 6-12 inch range and the overrunning, frontogenetic, nature of the snow will keep the density a little higher. Most importantly, absolutely positively no rain or ice to deal with.

Thursday should be generally dry, chilly but only slightly blustery. Temperatures will struggle to get out of the teens but February-style sunshine should be a comfortable addition to the ski day.  Expect more clouds over the high country Friday with similar temperatures and some instability flurries and snow showers.

My attention today has turned toward a potential storm this upcoming Sunday and Monday the 9th and 10th of the month. There is a more potent amplification in the jet stream that is expected around this time, and the jet does not appear to be overwhelming enough to crush a potential storm would one develop. And as it turns out, one such storm should develop, forming again along the Gulf Coast and advancing northeast toward the Virginia Tidewater. I gave a shout out to the American GFS model over the weekend (via twitter) since cycles of this model run showed this system exploding through its maturation process and dumping upwards of two feet of snow across interior New England late Sunday into Monday. The heavy snow potential hinges on the storm tracking close to Cape Cod. The other two major medium range simulations (the Euro and Canadian) have hinted at glory, but as a whole, track this potential big system at least 100 miles east of Cape Cod and would thus mean lower snowfall totals. This clearly has the potential of being one of those season-defining best snows of the year, but to fulfill some of those American GFS fantasies, the storm will actually need to deepen much more efficiently than what is indicated by the Canadian and Euro model packages. Each scenario is different, some storms we would prefer to stay flat with minimal deepening. In this instance however, a mature system will effectively hug the Atlantic Coastline and throw mammoth amounts of moisture across interior New England. All we can do at this point is just hope.

Looking farther into the future, there is a blast of cold that should impact the region in the wake of any snow early next week. The cold shouldn't exceed anything we haven't seen already this year and should moderate by the middle of the week. Another weather system is then expected to approach the region later in the week with more potential snow just prior to the weekend of the 15th and 16th. President's week lies beyond the 16th and their are signs of a tightening of the jet in the Pacific. The result should mean a moderation in temperatures although at this time there are no glaring signs of a major New England thaw. The AO appears to be slightly negative with a neutral NAO and a strongly negative PNA and thus our "favorability" index is negative.

Saturday, February 1, 2014

Can't complain, lots of snow and potential snow to talk about

Hard to complain with any part of the outlook as of early February 1st. Yeah our weekend system could have been more productive, but we should make out ok in spite of a low pressure center which is expected to track into Quebec (just as the Euro model predicted a few days ago). Model cross sections keep readings at or below freezing, and I mean just barely at or below freezing, throughout the event. This essentially means that we should see a burst of snow Saturday evening with a few inches falling in a short period of time. During the overnight hours, snow should taper off and Sunday should consist of clouds and some flurries or drizzle (depending on your elevation) with temperatures hovering in the middle 30's. The milder readings Sunday will mean that the 2-5 inches of snow that falls Saturday night turns pretty wet but the event clearly appears to be an overall net gain for the mountain.

Colder air filters back into Vermont Sunday night as high pressure builds across the state. A wave of low pressure will pass well south of the region spreading some snow and rain into Pennsylvania, New Jersey and perhaps southern New England but the mountain should stay high, dry, calm and relatively seasonable through all of Tuesday. Our midweek storm which is a moist but otherwise relatively garden variety low pressure center appears, as of early Saturday, to be "pure gold" as far as we're concerned. The expected track of this storm has shifted south and two of the three major medium range operational models have the system hugging the southern New England coastline Wednesday. This is terrific news not only for MRG but for the entire state because the results should be a widespread very healthy (probably not epic) snow event. The snow would begin early Wednesday morning, persist through much of the day and taper off some time in the evening. Accumulations will need to be fine tuned over time but look as of now to be in the 8-16 inch range. 

Temperatures will be chilly in the wake of the snow Wednesday but not intolerable. Thursday will be a little blustery with temperatures in the teens. Friday will be calm with better visibility but with similar temps to Thursday. The much discussed "activated" pattern appears to have another gift in the goody bag for the weekend of the 8th and 9th. We have yet to see much clarity on the personality of this potential storm but I would not be surprised to see something somewhat similar to the midweek storm. Low pressure should have another chance to gather moisture in the gulf and then head northeast. We just need another favorable track and we will be lined up for glory. I would just add before signing off that the timing for this appears to be Sunday Feb 9 although this could change.