Cold and snow to advance on the Vermont high country

The road to recovery begins a little sooner thanks to a wave of low pressure that will bring a swath of precipitation to New England. Mad River Glen is on the northern edge of this shield of moisture but the northern edge is the place to be for snow. It won't be a huge amount, but 3-6 inches is a welcome sight after the damaging and destructive weekend thaw.

Break out the welcome mat for the polar jet after Wednesday's snow. With it will come the arctic cold along with flurries and snow showers Thursday. The PJ will be pretty ferocious but its southward advance will stop over New England and the arctic cold will temporarily be confined to northern New England through the weekend. This also means that precipitation through the weekend will come from disturbances rotating through this powerful jet which at most will take the form of a potent clipper system. A series of three disturbances between late on Friday through early next week should all bring the chance for flurries or snow showers. Each successive feature should be stronger in nature and more capable of bringing fresh snow to the mountain. All three of these relatively moisture hungry systems mark the boundary between cold air to the north and west and warm mild air to the south and east. Light snow Friday evening into Friday night from the first of these disturbances could bring 1 to as much as 4 inches to the mountain by Saturday with the 4 occurring near the summits. Sunday's system appears a bit more dynamic and will have a better pool of instability in its wake possibly yielding 3-7 inches during the day. The last of these three features has the best chance of interacting with the Atlantic Coast. Such an interaction doesn't necessarily mean Vermont gets big snow but the potential does exist for a modest accumulation Monday night into Tuesday.

The cold weather will also play a big role in this upcoming story. This will ultimately become one of the more impressive outbreaks of cold in two years certainly besting anything we saw in last years pathetic excuse of a winter. The "teaser" blast of cold Thursday night into Friday will bring temperatures back below zero but the successive and more vigorous disturbances Sunday and Monday night will bring the Polar Jet further south and advance a serious chunk of cold air into large portion of the eastern United States. The New England high country could certainly see a 1-2 day period next week where temperatures struggle to get above zero even during the day and fall to -10 or even -20 at night.

There is more potential for snow late next week, again coming generally from clipper systems or terrain induced fluff. As mentioned in prior postings, the potential for a more organized system gets higher by the last full weekend of January and beyond. I'll discuss this in more detail in a subsequent update.

From very mild to very cold in the span of a week

It's always darkest before the dawn and Sunday's 40-plus temperatures marks the peak of what should be our bleakest period this month. Honestly though, this stretch of mild weather could have done even more damage. 2-weeks ago I was honestly concerned that the pattern would produce multiple days of 50-degree temperatures and some heavy rain to go along with it. Much of the rain with the approaching cold front will actually occur in the Midwest and across the Canadian provinces of Ontario and Quebec. A minimal period of rain in the pre-dawn hours Monday morning will probably amount to less than a quarter of an inch and falling temperatures should finally end the snow melt. The SCWB, in some previous posts, had teased about wintry precipitation resulting the one or two waves of low pressure that are expected to form along the suppressed stationary boundary in the coming week. This boundary however will be further south however and forecast for the coming days is substantially drier and colder.

The remaining base will obviously have hardened considerably as temperatures fall. The sooner we can get some new snow, the sooner we can forget about the past few days. As was indicated via twitter, we are headed from one extreme to the other as the pattern will go from one that supported mild weather to one that will support very cold weather. The arctic air will come in the form of a teaser blast late this week before the motherload arrives next week. It seems like it has been forever but at least for a short time, the prevailing negative NAO will align itself with a positive PNA or west coast ridge. This will ultimately lead to a widespread cold outbreak for the eastern United States and conditions will be especially cold across New England beginning Friday and persisting at least a week. Within this stretch we will mostly have to depend on clippers or quick moving upper air disturbances rotating through the polar jet. The first such system comes Thursday with the initial teaser blast of cold. We may only get an inch or two out this and perhaps even less if we are unlucky but this should be the first of many chances. Two clippers, one over the weekend and one marking the bigger arctic outbreak early next week both should bring some new snow to the mountain. One of these two clippers could also blow up into something more significant upon interacting with the Atlantic coast.

Big snows come to Vermont once you add the southern branch of the jet stream into the mix. The southern branch gets involved when it undercuts the ridging in the Pacific. We don't expect this to happen over the next 10 days or so but beyond 10 days (beyond January 24th), it does appear more promising. We will continue to have at least weak support from the AO/NAO combination through the rest of the month but we do lose the support of the PNA. This will cause the arctic air to relax its grip on the region but allow for more storminess in the pattern.

Back half of Jan looks pretty good !!

With that thought, one has to start with that memorable quote from the end of the movie "Trading Places" starring Dan Akroyd and Eddie Murphy. Looking good Billy Ray !!! Feeling Good Louis !!! This dialogue taking place on the beach after they exacted revenge on Mortimer and Randolph Duke while striking it rich trading frozen concentrated Orange Juice futures. I want this for us at MRG but I want our dialogue to be in the powder obviously. The European and Canadian ensembles could have us indulging in a bit of that fantasy. This would all happen after the 15th and after some rain and very warm temperatures.

The gory details of the coming weekend are not worth spending too much time on. The first area of precipitation arrives in the form of rain and in some areas freezing rain Friday evening. Most of this will be over with by Saturday, a day that should be dominated by low clouds, fog and drizzle with temperatures hovering at or just above the freezing mark. Temperatures and dewpoints could then push into the 40's Sunday with a few periods of rain. Models are hinting that some low level colder air could linger into Sunday thanks to winds that might not be as strong as initially assumed. I am hoping for such an outcome since it's all about damage control Sunday and Monday. The lower the dewpoints, the lower the winds, the lower the loss of snow.

Arctic air will move back into Quebec Monday and eventually force its way underneath the large east coast upper air ridge. This sets up that big temperature gradient I was discussing a few days ago. Temperatures in coastal Carolina and Virginia could push into the 70's while arctic air returns readings back to near 30 in northern Vermont. Waves of low pressure along this intense airmass boundary will move northeast but models have had a difficult time determining which of these waves, if any of them, will be of any consequence. Based on the last round of data our next shot of precipitation would be Tuesday and it's much more likely that it will fall in the form of snow or sleet. This would give the cold air another victory in Vermont in what looked to be a tough fight. We could use new snow or sleet next week since the mountain will have hardened quite a bit from the weekend rain and freezing rain.

So the talk this weekend is that of a thaw and the talk next weekend will be cold. A very big about face in less than 7 days. The combination of a building blocking ridge over Greenland and the evil empire (which will actually drift too far east for its own good) will allow another Polar Vortex to make a run at southeast Canada. Some very cold temperatures is the likely result with some snow preceding it Thursday/Friday of the light variety. Readings for the second time this month should plunge into the -10 territory during the overnights and struggle into the single numbers by day although there is still time for a few variations in this forecast.

The back half of January forecast hinges on two points. The first being that the negative NAO (caused by the blocking ridge in Greenland) begins driving the train. The second is the westward migration of the "evil empire" as it did during the back half of December ultimately leading us to some post-Christmas glory. The European and Canadian ensembles show strong indications of such an evolution. The American long range ensembles show a much more potent Pacific driven pattern however with much less of an influence from the blocking. The American model and ensembles have been erratic to say the least as of late and at times have performed poorly so I am inclined to favor the two other over the one. The other very important question relates to what kind of activity will we see in such a pattern. Can we move into a semi or fully split flow regime that resulted in the succession of storms in late December ? or will it stay dry. I think the former is possible since the polar jet will relax somewhat after the 22nd of the month while some energy will be allowed to undercut some of the mid and high latitude ridging in the Pacific. Its not a clear cut situation yet but I hope we can get a bit more clarity in the coming days.

Thaw still expected Sunday/Monday and some icing possible next week

The mountain has been hanging in there pretty good so far. The arctic cold has receded and Pacific air is largely encompassing New England. As of now, the effects of this have been minimal thanks to the deep snow, low sun angle and so far light winds. The latter of these will be the most critical in the coming days. So long as we keep the wind down, the relative warmth that has invaded the middle layers of troposphere will be unable to mix to the earth's surface. Winds will increase during the day Wednesday as an upper air disturbance and area of low pressure centered well to the region's north approach. Temperatures may creep above freezing again but snow showers will commence late in the day as the instability increases. I would expect maybe an inch or two from this followed by a dry and somewhat sunny day Thursday with diminishing winds and temperatures again near or just above the freezing mark.

The wind issue will become even more critical as the weekend approaches. Understand that the upper ridge along the east coast is mammoth in nature, easily supporting record breaking warmth in areas where the lower troposphere is well mixed (windy). Areas that are cloudy with light winds can avoid this fate. Much of Vermont will successfully do this Friday as clouds cover the state with temperatures still in the 20's and 30's. Precipitation from a decaying wave of low pressure will arrive later in the day and although temperatures will in many areas be above freezing by then, some areas could see some freezing rain. Most of this will be over with by Saturday morning except perhaps for some drizzle. I think Saturday's potential warmth could also be thwarted by clouds, of the low clouds or fog variety which would mean another day with temperatures in the 30's. Some sun on Saturday could push temps into the 40's however.

Sunday and Monday is when it could get real ugly. Higher winds, higher dewpoints, a period of rain and an extended period of above freezing temperatures will do damage to our snow. Arctic cold is expected to seep back into the region slowly beginning Monday but hardly in decisive fashion. The colder air will actually be undercutting the very persistent and still very potent east coast upper ridge. This undercutting will set the stage for a dramatic temperature gradient stretching from the Ohio Valley into New England. Waves of low pressure along this boundary, one or perhaps two of them could impact the region with precipitation. This is a battle where the cold air seems mostly out-gunned but there might be enough available to set the stage for an extended icing event next week. Arctic cold undercutting large east coast ridges does happen now and again in New England and some big ice storms have been the result. The one that comes to mind is early January of 1998 where (if I can remember correctly) members of the MRG coop volunteered to clean out all the tree damage from our beloved gladed terrain.

Eventually the east coast ridge will get pushed out and it will happen quite abruptly with some very strong Arctic chill possible for the weekend of the 19th and 20th. Ensembles have diverged a bit on the overall "favorability" of the pattern but I continue to think that the negative NAO will win the day, producing an extended stretch of rain-free weather and below freezing temperatures.

Thaw for the upcoming weekend, but lots of promise for the end of January

The Sunday snow concludes one of the better stretches of early season skiing the mountain has seen in the last decade or so. Even in some of the big winters like 07-08, and 2010-11, big warm ups during the Christmas and New Years holiday vexed us a bit. This year, it will be a mid-January thaw that crimps our snowpack. We may however, have reached a bit of a turning point. This point being defined by the time at which I have become convinced that the building snow pack will not be completely blow-torched away by a thaw. This point being the time when we see the light at the end of the tunnel before even entering the proverbial tunnel.

Arctic chill will continue to grip the region through Monday night meaning seasonable January temperatures. The evil empire then brings its dreaded Pacific air to the region Tuesday. The deep snow cover across interior New England, low January sun angle and lighter winds Tuesday and Wednesday will keep the effects of the pattern change more on the minimal side. Temperatures will challenge the freezing mark both Tuesday and Wednesday but will not get past the mid-thirties except perhaps in the Champlain or Connecticut river valleys. The sun angle plays an especially large role here since the same set of weather parameters might yield temperatures in the 50's were this mid-March. Models have also redefined our late week weather a bit and not in a bad way at all. Instead of commencing an onslaught of mild southerly breezes and excessively above freezing temperatures, a vigorous upper air Pacific Ocean disturbance will be allowed to track across the Great Lakes and drag a limited amount of both instability and colder air to the region. Temperatures will remain on the milder side of average but snow showers Wednesday night and Thursday along with sub-freezing temperatures is much better than what the forecast looked just 2-3 days ago. Such weather does not melt snow.

The big trouble period begins late Friday and persists through the weekend. It is at this point when we get flooded with mild air and ultimately get a period of rain. This happens as the pattern becomes more amplified with a deepening trough in the west and an even more well-defined upper ridge in the east. It will unfortunately be a bit ugly as a storm system gathers steam in the middle Mississippi Valley and heads well into Quebec. The period of rain is likely Sunday, although some of this also timing could again be re-adjusted. Temperatures could get into the 50's as well, a full 30 degrees above average and enough to challenge a few records but thankfully this should not persist too long.

When trying to assess the evolution of the long range weather pattern, I have always tried to look at the picture on a grand scale and tried to pick out big features on this scale that might win the day. It is a very inexact science since not only can your own assessments be wrong but the assessments of the model guidance can also be wrong. Although the evil empire is clearly the big feature during the next week or so, the negative North Atlantic Oscillation (NAO) will challenge its dominance and eventually, in my opinion, become the alpha as we head toward the last third of January. The battle between the evil empire and the NAO could be an epic fight, especially between the 14th and 20th of the month and the fight will be manifested in the form of a few storm systems during this period. The pattern will support the return of some very cold air across the plains and eastern Rockies and will ensure that this month will be one of the eastern Rockies coldest January's in a while. The pattern however will also support the continuation of mild air across the southeast and Mid-Atlantic states.  Storm systems will form in the southern plains at the junction point of the very cold arctic air and warm moist air from the Gulf. The storms, perhaps one of them turning very potent will move toward the eastern Great Lakes and threaten to bring warmer temperatures into New England. There should be a decent overrunning surface to support some snow but too much warm air means sleet and freezing rain and perhaps even worse if a strong storm were to move well into Quebec again.

The farther we move into late January, the more favorable the prevailing forces become so although the next weekend looks a bit slushy, futures weekends appear much better.

And I almost forgot. Hockey is back

More light and fluffy powder for the weekend

Temperatures struggled past zero Thursday but should moderate through the weekend though interior New England, specifically northern Maine, will be the nation's cold spot. Of more importance is the intermittent light snow throughout the day Friday which will likely yield 1-4 inches of very low density fluff to the mountain. The culprit for this is the last disturbance associated with the exiting polar vortex. Flurries could continue through Saturday but accumulations will be minimal and it will instead be mostly cloudy and cold with daytime temps near 20. Another weak area of low pressure will push through the Great Lakes Saturday and approach early Sunday. This is a putrid looking system but some limited moisture and its proximity to the region will allow for another extended period of light snow Sunday into early Monday. The colder temperatures will continue to support snow of the fluffy, low density variety as described above and accumulations could thus be higher ranging between 3-7 inches. This also could make Sunday or Monday a good day to reserve for MRG before we go off our own little fiscal cliff (although that might be a bit over the top).

In the last few updates, I have spent some time "dooming and glooming" about the pending adverse turn in the weather pattern. At the very least, we are in for a tough stretch next week but there are ways we can limit the damage and potentially move back toward a more favorable pattern as soon as the 14th or 15th of the month. Regarding the latter, the ensemble packages have been quite ambivalent but I am hoping the models/ensembles hash out their own little fiscal cliff deal and provide us with some sort of soft landing and although such hope can be dangerous, their are ways this could happen. More on that in a bit. The rough stretch I alluded to begins during the middle of next week and could involve 1-2 rain events between Wednesday and the weekend of the 12th-13th. There is some lingering arctic chill in eastern Canada but the weather pattern will make it very difficult to allow for any involvement. At best, the first batch of precipitation could include some freezing rain, but at some point we are going to have to face the 40-50 degree music and rain. 

The Pacific evil empire is the primary culprit behind the turn toward warmer temperatures and the likely rain. By the 12th and 13th of the month however, height rises (jet stream ridging) will expand to include the Aleutian Islands, the North Pole and Greenland. This is another ring-around-the-rosie scenario that forces some very cold air into North America toward the middle of the month. The dilemma for Mad River Glen is that the cold is favored in the wrong location - the western United States. Still, the negative AO and NAO is an appreciated ally and the GFS ensembles have responded by showing a much earlier return to colder weather and winter weather events then the European Ensembles. I think both packages of information are guilty of succumbing to respective biases but the trend today was to at least open the door for some better possibilities for the second half of January.

Evil Empire returns after a cold finish to the week

MRG continues to bask in the glow of a great holiday week and a remarkable reversal of fortunes to end 2012. The "basking" can continue through next weekend as the Polar Vortex rotates through northern New England this week and off into the Canadian Maritimes. Accumulating snow will be minimal although weaker disturbances are capable of bringing flurries and light snow to the mountain. The best chance for this comes Wednesday and again on Friday. We talked about some of the cold weather in the last update. Interior New England will have the lucky distinction of seeing the coldest weather in the U.S. over the coming days. The coldest period should be Wednesday night into Thursday morning with readings getting to about -10 F and struggling to get above 10 during the day Thursday. Temperatures will moderate for the weekend with readings getting close to 30 during the days. An increase in the clouds Sunday should be followed by light snow later in the day or at night as a more significant clipper disturbance brings a good chance for a 2-6 inch snow by Monday morning.

The Sunday night/Monday clipper is the best chance for the mountain to pick up some new snow over the next 10 days. The headline does not lie unfortunately. The "evil empire" is back and signs of trouble are all over the medium range models and ensembles after the 10th of the month.  The Arctic Oscillation (AO) and North Atlantic Oscillation (NAO) are expected to continue to be on the negative side of zero which is a much needed and encouraging ally in what will be a very tough fight to preserve our snow (and thus the reason the favorability index isn't worse). I didn't give the "evil empire" its name for nothing however, it is the "death star" of winter weather. Especially when coupled with a trough over Alaska, the feature not only encourages zonal flow, it favors the cold weather across the western North America. The effects of all this may not begin to impact MRG until the 10th of the month and will not be uninterrupted. Overall however, this is going to be 2 weeks of a generally adverse pattern that will continue through about the 22-24 of the month (loose prediction).

Much of the United States will be very much on the milder side of average by the end of the upcoming weekend. Canada however will continue to remain on the colder side of average for much of next week. To save the 2nd full weekend of the month we are going to need some sort of buckling in a very zonal jet stream that will allow some of this cold to fight its way back into New England. The models have yet to come into full agreement but as now they support a slow erosion of below freezing temperatures next week and a potential rain event by around the 10th of the month. These are ugly details I know, but we it would be wise to keep our expectations low for the middle of the month. Hope everyone had a happy and safe New Year.