Think Snow, Tweet Snow !!!

Friday, December 3, 2021

Wintry temps and a little snow this weekend and some snow potential continues for the middle of next week before the weather pattern takes a turn for the worse

 The forecast for Monday has deteriorated to trash which is a rude interruption to what could have been a nice early December 7-day stretch of sub-freezing temperatures. All indications are that this will be a tough month for winter-weather lovers in New England. We've talked about all the feedbacks working against us and when you add in a prevailing + Arctic Oscillation (AO) index and a positive Eastern Pacific Oscillation (EPO) the results will be predictably bad. We continue to see some very cold air positioned over Alaska and much of northern and central Canada but its a challenge to put this chill to good use in December, and Monday's torch is a perfect end-result example. 

We still have a wintry weekend to look forward to. Sunshine and near 10-degree temperatures early on Saturday will give way to some clouds. The snow from our benign weekend disturbance is not expected to arrive until after the ski day and in the evening. Northern Vermont appears to be the best area of accumulating snow in this period and this appears to be a fluffy 1-3 inch situation for MRG. Models are indicating a few clouds for Sunday so perhaps not total bluebird, but we can expect a decent dose of sun during the day and the warm advection clouds are not expected until after it gets dark. 

Most of the east coast is now expected to get a torch on Monday with soaring temperatures. Cold will linger for a few hours in Vermont under clouds but the inversion is expected to mix out during the afternoon allowing temperatures to soar into the 40's. A short period of rain is likely at some time late in the day before a cold front dries it out and cools it down. Sub-freezing temperatures are then expected to prevail for most of the rest of the week (through Friday) but can we get some snow before the weather pattern fundamentals turn ugly around December 10th. 

We have a couple of models indicating most of the moisture associated with a weather system in the middle of next week will be south of Vermont. We also have the American GFS model showing a more direct hit and decent dose of snow. Mix that data all together and you get an appetizing model consensus but I have some concerns about whether this system can actually organize itself enough to send moisture deep into interior New England. We have a very healthy baroclinic environment along the eastern seaboard working for us so the situation is certainly worth monitoring. 

The period between December 10th and the Winter Solstice does not look good as I mentioned. A Friday afternoon run of the European Operational model did bring in a decent area of cold late next weekend into Monday December 13th following a wintry mix-type event on the weekend of December 11th-12th. This was not supported by the corresponding run of the Euro Ensemble so though I am inclined to generally disregard it, the model did illustrate how cold air in nearby Canada might successfully make an intrusion in spite of the lousy weather pattern fundamentals. The risk of a multi-day thaw and rain however is pretty high in this time frame and this would be the point I would want to underscore before leaving you all for the weekend. Enjoy the wintry temps while we have them !

Wednesday, December 1, 2021

Cold weather and some light snow for Saturday while best snow potential shifts to the middle of next week

Our friends up in King Salmon, AK, one of my favorite names for a town, just finished the month of November with temperatures averaging 21 degrees below normal. King Salmon is not especially inland, sitting not far from the Kvichak Bay adjacent to the Bering Sea and just east of the Katmai National Park. In other words, this is pretty far south in Alaska and highlights what has been a month of incredible cold along the southern coastline of our nation's largest state. Much of this cold remains as of this post and has expanded to include much of northern Canada. It will remain locked in place for the foreseeable future and will make occasional appearances in Vermont but a bit more infrequent than I would like, especially after December 9th. 

Up until this aforementioned date, we do have some winter to discuss. The dynamic looking BC bomber system is unfortunately a flop. With the track of this storm now expected to be well over Quebec, the storm and its relative strength will help push above-freezing temperatures into most of the low lying areas of Vermont Thursday and any precipitation will be of the mixed or rainy variety. Above 2000 feet, rain showers Thursday afternoon will likely turn to snow by the evening. Flurries and snow showers are likely to continue into early Friday as colder air settles into the state. The mountains can expect a small accumulation from all this but I had hoped for more and I wouldn't bet on more at this point. I am more encouraged by another weaker disturbance expected to bring limited moisture to Vermont early Saturday. This arrives during a period of much colder temperatures and has the potential to provide our local high country with a few fluffy inches. Still a little difficult to say which part of Vermont will score the most from this moisture-starved system but we have as good of a shot at as anyone else of scoring a few inches. As I mentioned this disturbance comes during a decent multi-day stretch of sub-freezing cold which will begin with temperatures in the 20's Friday and continue through the weekend with single digit temperatures possible Sunday morning. Sunday looks like a December bluebird special, always appreciated by me during our darkest month of the year. 

I wish I had more conclusive and better info to report for early next week. The American GFS model has in the past and continues to show an inland Great Lakes runner, so much so in the last few runs that Vermont would get a full blown torch Monday and we would just forget about snow. Other data still points to a colder more wintry scenario but even this would be well short of ideal. Consensus has certainly moved away from the possibility of a storm tracking south of us and this makes the notion of heftier accumulations a very tough ask. My guess right now would be for a snow to wintry-mix conglomeration and we could get front-end thumped with a few inches. I am trying to avoid getting sucked into to any wishcasting vortex here and remind anyone that these lousy feedbacks (warm aggregate bodies of water around us) are not going to do us any favors during these close call situations. Some good news ? We do have a second chance during the middle of the week with models starting to signal at a more organized storm coming on the heels of a short-lived but somewhat intense shot of arctic chill Tuesday and Tuesday night. 

The longer range continues to look the same and not especially encouraging. Were it January or February, I could muster up some optimism that clashing of very cold air in Canada and mild air in the southeast US would serve us well. Combine the aforementioned adverse feedbacks with a decidedly +AO/EPO and tough sledding is clearly the most likely result. Any sustained stretch of milder air does appear delayed until at least the very end of next week (December 10) which would be a positive. The other positive continues to be the relative proximity of the very cold air in Canada. Much of the eastern United States is likely to avoid it but we are Vermont and are special in this regard so might get a little. To summarize though, I do not expect the period between December 10th and December 21st to be especially wintry or snowy and we should at least one very significant thaw. It will however be cold in the Pacific Northwest and snowy parts of the Rocky Mountain west. I would expect a few snowy headlines in some unusual locations as well.

Monday, November 29, 2021

Mostly cold for at least another week in northern Vermont with several chances for small accumlations of snow and 1 chance for a bigger one

At the Knapp Airport in Berlin, the low temperature of 11 and high of 29 on Sunday officially measured at 9.5 below normal, falling just short of 10 below normal. So the 6-month streak of avoiding the "10 below normal or more" cold remains for now. It is very likely to fall this weekend with more intense cold expected to land on northern Vermont atop of some snow cover. This highlights what is a decent short term outlook extending out maybe 7-10 days which includes a few chances for small accumulations of snow and 1 chance for a decent storm. We have some concerning weather pattern fundamentals to contend with beginning around December 8th but even this potentially less than optimal pattern leaves some room for encouragement. 

A mostly cloudy and chilly day Tuesday should be followed by some very light snow Tuesday Night into Wednesday. This is a very benign weather disturbance but is still capable of yielding a very low density accumulation. Milder 30-plus degree temperatures and some sunshine then follows for Wednesday before clouds in advance of a vigorous BC bomber type system arrive Wednesday evening. Even without a ton of moisture, this southeastward moving system has an impressive look. Current forecast models have our area of north central Vermont missing the best quadrant for snow but not by much (we would be 50 miles too far south). Even still, we should expect a period of snow Thursday along with near freezing temperatures and some snow showers early Friday with the arrival of colder weather. A small 1-3 inch accumulation would be my best guess with this for now but this could rise or fall depending on the exact track of this weather system. 

The Thursday storm is the first of what is a relatively active pattern with one consolidated jet stream and a decent supply of early December chill in Canada. An initial surge of colder weather should arrive by Friday which is likely to mark the first of a 5-day stretch of sub-freezing temperatures. We are likely to miss out on some light snow that might impact portions of the Mid-Atlantic Friday night but temps could fall to the single numbers and only rebound into the teens on Saturday with a repeat of this for Sunday. The potential storm would impact the region Sunday night or Monday. It appears to be involve energy from the Pacific that would get a big infusion of energy and moisture from the relative warmth of the Atlantic Ocean. Models aren't even close to sorting through particulars of this storm or even the presence or absence of said storm. I've seen a wide variety of outcomes which would indicate a forecast that is likely to evolve over the coming days. If there is an identifiable trend in recent data, it does involve colder temperatures during the period in question which is certainly good news. This cold weather is likely to remain in place across New England through at least Tuesday December 7th as I mentioned but I could certainly envision this continuing through most of next week in spite of some operational models suggesting a mid-week torch. 

The longer range ensembles are painting a picture consisting of a pattern without any high latitude blocking and with more averse jet stream activity in the Pacific. A strong mid-latitude ridge is expected to develop in the Pacific and unsurprisingly, it is indicated to set up right over the warmest blob of water discussed in the seasonal outlook. As a result, Arctic air is expected to retreat after December 8th so where is the good news here ?. Well, we successfully managed to get some of the coldest air in the world on our continent and it should remain there even as the pattern  turns move adverse next week. As I mentioned in the seasonal outlook, we are facing down some pretty tough feedback mechanisms in the form of various bodies of warm water temperatures (Great Lakes, Hudson Bay, western North Atlantic Ocean) .We need some help in this regard and we are getting it in the Hudson Bay, a region of central Canada that saw some incredible warmth in Autumn. Much of northern Canada and especially Alaska has turned very cold however and those conditions are expected to remain over the next two weeks and beyond. We can thus be confident that the Hudson Bay will freeze on schedule (mid December), eliminating at least one bad feedback ahead of Christmas. Additionally, the colder weather in Canada will be close enough to New England for an impact and ensembles, although milder after December 10th, are not suggesting a sustained torch in Vermont.

Wednesday, November 24, 2021

2021-2022 Winter Outlook: La Nina returns in a more weakened state but a lot of arrows still point mild !

 It's been a long wait for colder weather this autumn across northern Vermont but winter is coming in fast now that the calendar has turned to November and our friends at Sugarbush are celebrating opening day as of this posting on November 24th. As I get older, I feel like the shorter days almost requires one to get excited about the arrival of ski season and the various winter weather possibilities. Yes, the caution flag was raised early this autumn with La Nina lurking and a seemingly endless stretch of anomalous warmth stretching into October but the weather is always evolving and I like to hold back any bold predictions until late November allowing weather conditions to continue to evolve.

The last time cold weather set off any fireworks across the lower 48 was February. Since then, the weather has oscillated between slightly above and the much above range not only across interior New England but for much of the United States and Canada. Locally speaking, what has made this several-month stretch of warm weather unique is the glaring lack of anomalous cold, even for a few days. You have to go all the way back to Memorial Day weekend to find a day in northern Vermont that was at least 10 below (the already recently warmed) 30-year average. To add some perspective to this, we have recorded 28 days since Memorial Day with temperatures at least 10 above average and we've yet to break the streak even with the recent colder weather we've seen the past few weeks. It explains the late foliage year we experienced both in the Great Lakes Region and New England since multi day stretches of anomalous cold are very much a normal part of New England should see from the standpoint of variability. The extended period of warmth has created some problematic feedbacks that we can discuss in a later paragraph but this has certainly been the biggest headline when discussing the weather this past several months. With that, we are ready to take a plunge in to the "what can we expect this winter" domain.

ENSO (El Nino/La Nina) 

Let us start with the ENSO situation and get a handle on that. Last year we had a significant La Nina that appeared to be building as we progressed through November of 2020. That particular ENSO peaked in very early December and very slowly subsided as we progressed through the duration of winter, finishing March at less than half the strength of that early December peak. Once again, we are seeing La Nina conditions in the equatorial Pacific but they are weaker than last November by about half a degree. Though this still puts ENSO into what I would consider a more "La Nina" mode, if equatorial waters were to warm, relative to average, by about half of a degree C, we would be be looking at a nearly neutral ENSO. Though I tend to prefer a weaker El Nino as opposed to La Nina, a weakened ENSO of any kind does serve our winter weather needs a little better. This relationship is hardly perfect but based on about 60-70 years of hard data, a strong ENSO of any kind does load the dice for a dud winter. We've had 15 strong ENSO winter's in the last 60 years which comes out to about 1 in 4 and 8 dud winters in that same time frame which comes out to a little less than 1 in 8. About half of those dud winters occurred with a significant ENSO present though which suggests that a strong ENSO about doubles the chances for a 2015-2016-like abomination. This winter marks the 10 year anniversary of the 2011-2012 horror show, a torch-fest largely brought on by some horrific prevailing jet stream conditions in the Pacific. We had a modest La Nina that winter that measured out at about -0.85, not too dissimilar to conditions right now. Interestingly, the 2011-2012 winter came on the heals of a stronger La Nina and one of the snowier winters in New England illustrating the imperfections in this relationship.  The best way I can summarize the ENSO situation for this winter is that I am not too worried about it right now and some other combination of factors will allow our weather to sink or swim. Here is a chart I put together showing a recent history of ENSO during the winter months and a few adjectives describing Vermont weather during that winter. 


All Things Pacific 

Moving on to the all-important Pacific, and I can underscore all important because it's had much to say about the outcome of recent winters. We've seen about 20 months of negative PDO conditions with the index generally amplifying in that direction over that time frame. They've done a number on some of my data sources regarding the Pacific Decadal Oscillation but the index, according to this graph, appears to be hovering around -2 which is pretty significant. We haven't seen anything like this since late 1999 into 2000. Though I consider the state of the PDO very significant, I prefer taking the deeper dive into sea surface temperatures in the mid-latitude Pacific in search for better answers. Why do I prefer this ? Because the actual PDO index seems driven heavily by the state of SST's over a small region near the west coast of North America while the weather pattern can be driven largely by the state of SST's over a broader expanse of the Pacific. 

I affectionately refer to the "red blob" as a persistent but vast area of warm SST's in the mid-latitude Pacific. It's been there for a while now, over two years to be exact. It largely ruined the winter of 2019-2020 and was an adverse force last year but was largely neutralized by prevailing (-) Arctic Oscillation conditions. It's still there as of this November but over the past 6 weeks, the area of warmth has shrunk and has shifted south and west. Meanwhile, an area of cooler water has strengthened and now covers a large area of the northeast and east-central Pacific Ocean. I suspect much of this has been weather pattern driven (but I can't say that definitively) but it's been interesting to watch this happen while at the same time, the +EPO has been mitigated and conditions in the Pacific look marginally favorable for cold weather in eastern North America over the next few weeks. Overall, in spite of how negative the actual PDO index is, I consider the conditions in the Pacific to be better overall than they've been the last two years. This doesn't clear all the roadblocks however since we will certainly need help from other fundamentals. 



 SST Anomalies last November



 SST Anomalies more currently



Snow/Ice Buildup

The buildup of snow/ice across both the North American continent and especially the Northern Hemisphere as a whole, in autumn, is certainly something I and many others consistently watch when trying to make a guess on weather for an upcoming winter. Over the last several years, we've seen rapid buildup's of snow across the NH and the trend has been so pronounced and so consistent that it is reasonable to speculate that climate change might be playing a role. More specifically relating how changing thermals in a less icy arctic in autumn might directly cause a more rapid buildup of snow over these areas. A reasonable assertion to make but this is where I punt to the more academic crowd for more definitive answers. In the case of this autumn, 2021, snow coverage in October registered well under 20 millions of sq km for the first time in 10 years. The exact number 18.14, is more in line with the 55-year average but additional data in November is showing that we are now below average we are now on pace to have the slowest buildup of snow since 2008-2009. While the above is certainly noteworthy, so are sea ice conditions in the Arctic throughout the summer and into fall. They made a bit of a comeback this year with substantially less ice melt than in 2019 or 2020 and a fairly rapid freeze-up in October/November. Recall that the Chukchi Sea, the area of water northwest of Alaska, was wide open well into December during the fall of 2019 and has completely frozen as of the middle of November 2021. This contrast in conditions would lend credence to an open water/rapid snow cover relationship and certainly an interesting potential consequence of our warming world. 



 Snowcover the last several October's















For this winter, the sizable drop in snow cover over the Northern Hemisphere, by 3 million sq km and almost 7 millions sq km in November can't be ignored. In spite of better sea ice conditions the slower buildup of snow is still a warmer feedback this winter that we will have to overcome. Though we've covered this ground before, its always worth a reiteration. On a scale as large as a "hemisphere" a larger snow cover area provides a more fertile ground for cold air pooling and more intense areas of arctic chill. 

Atmospheric Tells

Our last section covers the "Atmospheric Tells", a broad category that analyzes whether recent trends in weather both locally and across the continent reveal any behavioral tendencies that might either continue or might portend future weather conditions in any way. I always try to be very cautious in sifting through this data, trying to focus on consequential variables while ignoring those that might be immaterial. This is a very subjective exercise and leans heavily on the years of experience doing this and can rely heavily on persistence-based forecasting. Though a "persistence" forecast, essentially calling for the continuation of weather conditions currently being experienced, isn't exactly as bold as bombing it down Paradise, it deserves a place in the equation. In the case of this year, it's an unfortunate place since the most glaring trend in recent weather has to do with the persistent warmth and particularly the lack of intense anomalous cold discussed in one of the opening paragraphs. This long duration of this recent trend has been self reinforcing because of the negative feedback loop that the region has been sucked into. The warmth has been expansive, especially this fall and covers all the Great Lakes, Northeast and much of eastern Canada. The result has been a Great Lakes aggregate, parts  of the western Atlantic Ocean and much of the Hudson Bay that are seeing water temperatures of 5 to as much as 10 degrees F above average. Some of these anomalies have been mitigated in the last few weeks by a changed weather pattern but more work will need to be done. Much of Canada is expected to be quite chilly over the next few weeks going into early December and I am hopeful that we can start to freeze the Hudson Bay close to the usual time. Right now, that very large, nearly 500,000 square mile body of water is wide open making it difficult for intense cold to make the trip into eastern Canada without modifying substantially. 


In a final summary, we can start with the  more encouraging news relating to the changes discussed in the eastern mid-latitiude Pacific Ocean and an altered weather pattern finally mitigating some of the negative SST feedbacks in the Hudson Bay, Great Lakes and western Atlantic Ocean. La Nina remains a force albeit a little weaker than a year ago. Mostly however, the data is suggesting a mild winter. Even with the recent changes in the Pacific, ocean water temperature configurations there remain adverse and we were only able to overcome that last year with an usually negative and persistent negative Arctic Oscillation. Those conditions are very unlikely to repeat. The worst roadblock on the temperature side has to do with much of what was discussed in the previous paragraph. Recent trends have been horrible for cold and we now have an ugly set of feedbacks to overcome. 

It's more easy to retain some optimism on the snowfall side of things. La Nina winters, even the weaker versions, favor a storm track aimed more at us than south of us and though I would expect to see a wide variety of precipitation types, interior New England would be a favored location to "bullseye" a big storm.  Warm water in the western Atlantic is not especially positive for the temperature outlook but it can provide a lot of fuel for big storms and I am optimistic we see a few. Barring something anomalous from the teleconnection indices we monitor, we should expect both good and bad periods of weather overall with decent stretches of weather rudely interrupted by an inopportune thaw. Nothing unusual for Vermont. Welcome back everybody and Happy Thanksgiving ! 

Friday, April 30, 2021

Winter 2020-2021 review - What could have been !

 The 2020-2021 ski season was certainly compromised as a result of the ongoing Covid19 pandemic but we still had one at Mad River Glen and we thank the efforts of all staff members that helped make that possible. On the weather side of things it was interesting because it almost always is.. We had two big east coast storms, a historic and very damaging cold wave in Texas and a persistently negative Arctic Oscillation yet in the case of northern Vermont, I can best summarize using 4 words. What could have been ! 

As expected, the winter was dominated by a moderate La Nina. It strengthened very quickly in autumn but SST's in key regions of the equatorial Pacific leveled off at about 1C above average and then began to fade late in the winter. Also as expected, the sea surface temperature configuration in the Pacific did create a weather pattern that was dominated by a strong Pacific jet stream which proved to be a mostly invariable force throughout the winter. The more dramatic and less expected distinction relates to the aforementioned Arctic Oscillation. Recall that the winter 2019-2020 was dominated by a very positive AO, one of the strongest recorded in the last 75 years, averaging an index over+2 over a 4 month period beginning in December and ending in March. Over the same period 2020-21, we saw an average AO of -.82 and the very positive AO we saw just recently in March blunted what would have been an even stronger negative number. More than anything else, it was the negative AO which helped daytime temperatures in the MRV average 2 degrees colder during the recent ski season than the season prior. This is not an insignificant figure over a 4 month period and really should have resulted in more snow across the Vermont high country. The stake at Mt Mansfield doesn't lie however. The snow season started below average and never caught up and quite honestly, I chalk it up to whole lot of bad luck. It simply should have been better given the selection of ingredients available to us. I'll expand on this point more when we review what happened in February. 

November of 2020 bore no resemblance whatsoever to what we saw during Snowvember 2018 or even last year. We started mild, we finished mild and the minimal snow we saw in between melted by the start of December. There was almost no support for early season winter weather in November across New England but the AO made the critical turn early in December and this began a long period of time where high latitude blocking effectively suppressed surges of more intense milder temperatures (with one exception). Interestingly, the blocking was largely confined to an area that included Greenland, the Davis Strait, the Labrador Sea and portions of the Hudson Bay. Having such a large block in relative close global proximity to New England actually prevented eastern significant amounts of Arctic cold from impacting eastern North America; nonetheless, it was enough to finally bring a stretch of sub-freezing temperatures to the northern Vermont high country beginning around December 5. The coldest stretch of days occurred in the middle of the month out in advance of what was the first of two major winter storms for New York and New England. Initially forecasts kept the storm south of Vermont but hopes were kept alive by the "northward shift" possibility, which specifically refers to a medium range model bias that overly limits the impact of nor'easters on interior New England. The bias is real and it happened again, as forecasts began shifting the track of the storm northward and higher resolution models began pinpointing the presence of a massive pivoting band of snow within the storm near the Vermont/ Mass border. Man, did we get close ! The MRV missed what could have been some historic snow by maybe 50 or so miles. In Vermont, the band concentrated in a line from near Granville east to Windsor, Vermont and produced as much as 50 inches of snow with high amounts recorded even in areas that often get screwed because of unfavorable oragraphy. It was frustrating to miss on some terrific early season powder by very little but it foreshadowed much of what became some very bad luck in northern Vermont that plagued us throughout the season. The storm did showcase the material improvements in higher resolution modeling, specifically how forecast data was able to indicate the presence of the pivoting heavy snow band. Ski areas such as Magic Mountain and Okemo certainly got a chance to bask in the glory of this storm for several days. Further north, we managed to build a 6-10 inch that seemed to accompany a growing sense of doom as the forecast for Xmas deteriorated. 

Christmas was indeed a disaster but guess who had it on the bingo card back in October when Vermont Ski and Ride came calling for an outlook ! I got extremely scientific with this prognostication going with the theory that 2020 was full of piss and vinegar so why should Christmas be any different. The storm was absolutely a freakish occurrence given the weather pattern by getting caught in the jet stream blocking in eastern Canada rather than tunnelling underneath as most storms do in those circumstances. It was windy, it was mild and our snow was all but gone by December 26th. It was a terrible but fitting way to end a not so great kind of year. 

The start of 2021 brought almost instantaneous improvement to Mad River Glen. High latitude blocking in the jet stream finally began to score some victories with the first coming from a very garden variety storm that moved from the lower Mississippi Valley to southern New England late on New Years Day. Steady snow fell across much of Vermont and much of ski country in the northern part of the state scored 6-12 inches. Much of what fell ended up staying on the ground through early March thanks largely to the persistently negative Arctic Oscillation. Interestingly, however, eastern North American remained largely devoid of intense arctic chill as the plethora of high latitude blocking structures, were, for a time, closing pathways for polar air to move from the Eurasian Continent. That would eventually change but for much of January, Vermont manage to experience a very impressive streak of sub-freezing temperatures that were, at the same time, above normal. Following the early month snow, a stretch of dry weather persisted for over a week and temperatures remained rather comfortable, staying mostly in the 20's and low 30's and never really falling below zero. We began to see signs of a storm for the MLK holiday but with the cold weather holding a very tenuous grip on New England and the Christmas fiasco still fresh in my mind, I will admit some apprehension. It ultimately looked apparent that the storm would not follow the same fate as the one on Christmas Day. The initial storm occluded over in Iowa and the main precipitation producing storm reformed over New York City early Saturday. Though the snow consistency wasn't optimal everywhere, the storm was the best event of the season with over a foot falling across the high country surrounding the MRV. Colder weather in the ensuing week along with several small accumulating snow events made for some terrific conditions and that persisted through the rest of the month even though the MLK storm was the last to impact the state for the remainder of the month. As for the arctic cold, it finally showed up in New England on the last few days of January with temperatures dropping to as low as -20 in spots on Saturday January 31st. 

February 2021 is a month that will be long-remembered and not necessarily for the right reasons in some parts of the country. For the ski areas in northern Vermont, I consider the outcome quite unfortunate since the chess board appeared set up for an absolutely glorious stretch of winter and the results were rather ordinary at best with our rain-less, thaw-less streak ending late in the month. The 2nd of the the season's 2 big nor'easters struck on February 1st and 2nd as a classic Miller B type event with a Midwest storm transitioning its energy and moisture to what would become a much stronger coastal system. Indeed it was very strong storm and proved to be an epic event for the NYC metro with upwards of 2 feet falling in some suburbs. Snow did reach most of northern Vermont but accumulations were very garden variety and fell short of even some modest expectations. The snow that did fall was nonetheless a welcome addition to a 5-week stretch of sub-freezing, rain/ice-free weather and the week that followed was a productive one with small accumulations of snow making the first full weekend of the month, one of the best of the season. It was a point in the season where everything looked as if it was going to come up roses as the Pacific jet appeared to be finally relaxing allowing the persistent blocking at high latitudes to win the day and the month. What was even more encouraging was the continued presence of a La Nina-style southeast ridge; which, appeared ready to steer multiple storms in our direction as oppose to a confining the impact to coastal areas. Normally, I would embrace this setup and do so enthusiastically fully expecting epic results. 

The weakening Pacific jet was as an absolutely critical occurrence and indeed allowed the blocking at high latitudes to produce an highly amplified pattern capable of producing a cold wave of historic proportions across the Texas, Oklahoma other parts of the middle of the country. Arctic air began its southward advance around February 7th, initially affecting northern latitudes including Vermont. By the weekend of Valentines Day however, the pattern would become even more amplified allowing very extreme cold to make a full on assault on portions of the Gulf Coast. As the cold continued to look more intense in Texas, it was gradually appearing less intense across New England and expectations began to shift from bone-chilling cold to a more defensive posture of fending off surges of milder air. The third week of February, you know the one that includes the holiday looked like a could be a 2-storm type of week and ended up being a wide-left and a wide right form if ugliness. The first storm late Monday into Tuesday involved a big push of mild air and had lots of moisture but an initial, decent burst of snow turned to sleet and ice. The 2nd on Thursday, Feb 18th, made a southward shift in the days leading up to the event and resulted in little to no snow in northern Vermont. The month ended with a muted thaw but and it was a microcosm of a month that should've been better. 

And while Vermont was glazing over with ice or getting bested by coastal cities on snow, Texas was freezing in darkness. The cold wave sent temperatures to -14 in Oklahoma City which is about as cold as the MRV got all winter. Readings were below zero as far south as Dallas/Ft Worth and a low as 10 degrees in some outlying suburbs of the Houston Metro. The intensity and duration of the cold wave stretched an already flawed electricity market in Texas, overseen by ERCOT (Electric Reliability Council of Texas) beyond its breaking point. Much has been written and politicized about a weather event that proved more impactful than multiple high category  hurricanes making landfall at once.  Though I don't operate within the ERCOT sphere, the power markets remain part of my home turf and it was disappointing to see misconceptions made by familiar characters in the aftermath of the event. The most common one involved laying the blame at the feet of renewable sources of energy such as wind which supply Texas with a critical amount of electricity throughout the year. Texas, in fact, leads the nation in wind generation, a source of electricity that many cold weather climates rely on in high demand periods and do so successfully. The Texas market however does not operate with the necessary incentives to seamlessly operate during high load events and especially during historic cold waves. When the postmortem assessments are completed, they will almost assuredly show how dangerously vulnerable the grid was to a historic cold wave and that planning for such an event was very poor with a limited sample size of data used to make an adequate risk assessment. Texas, more than any other region, is susceptible to gas freeze offs which effectively shuts off vital supplies of  natural gas to power plants when they need it most. Wind, could have provided Texas with a critical backstop but ERCOT failed to provide generators with the proper incentives to winterize their wind generation which is commonly done for wind generators farther north. ERCOT also operates with a reserve margin that is considerably lower, often less than 10 percent during high demand periods, than our market (NEPOOL) in New England which is typically closer to 30 percent. A  less than 10 percent reserve margin in a region of the country that can experience very volatile weather and energy demand is not a market structure that ensures reliability and is instead hoping for a combination of luck (which always runs out) and market forces (which have a funny habit of conspiring against John Q Consumer at the worst time) to operate successfully.  Don't let anyone tell you differently, the situation in Texas in February was a miserable embarrassment for free-market advocates who can wax poetic about how all of this serves the consumer. It serves no one to freeze in the dark, which millions did for a span of several days.

The milder turn the weather pattern took in late February continued into March. The AO which helped power the widespread cold outbreak in February abruptly turned positive in late February and stayed positive through March and when combined with a still active Pacific Ocean jet stream helped make for a rather torchy and surprisingly dry month. That said, winter tried to make a last stand in New England and Vermont was one of a select few states to see a sustained stretch of winter early in the month including a day, on March 2nd where temperatures struggled into the teens. Fittingly however, Vermont saw a very limited amount of snow when it was cold. The high country did see a few decent snow squall events but at no time do we see snow from an organized weather system. Ski country did see some excellent weather for spring skiing however. By my count, the MRV got to experience 7 days of near 60-degree, sunshiney weather which is unusual for us and gave skiers several days of healthy spring conditions. Too much of a good thing can present a problem for MRG lift service however and all of that warmth ended the official season on April 3rd. 

April followed with more surprisingly pleasant spring weather in Vermont but this was rudely interrupted on April 15 by an elevation snow event which brought some heavy snow to the same portions of central and southern Vermont that seemed to get much of the best snow all winter. Another even colder event on April 21/22 brought snow to the northern Vermont high country and helped make April a snowier month than March in spite of a lot of warm weather. 

Years ago, a very experienced and seasoned forecaster shared with me his feelings about what was going to happen during the upcoming summer of 1999. He was a believer that the 11-year sunspot cycle could be correlated with the North American weather pattern. The 11 year sunspot cycle refers to the oscillating measure of observed solar activity where it takes 11 years to complete one full cycle. There are peaks and troughs of such activity with the most recent peak occurring around 2014 and a trough having occurred very recently. He never did actually sell me as to why and how the correlation exists but he pointed out how hot and dry summers have occurred in the same point of each cycle stretching back (at the time ) of 50 years. 1955, 1966, 1977, 1988 were all hot and dry with a high activity of tropical cyclones. The forecaster nailed the 1999 summer forecast and though I never was completely sold on the sunspot link, the verification stuck with me and I remembered it going into the summer of 2010. Once again it was hot and dry. So, if you made it this far in the review and in the paragraph, you can probably see where I am going with this. 

I won't sell folks on the idea that the sunspot cycle is a predictor of a prevailing weather pattern. I really don't know. I do believe however, as many of you know, that the weather pattern can provide tells as to future weather. I've watched many dry weather patterns in spring lead to hot and dry summers. We've had some precipitation in April and some more is on the way in the upcoming week but we've been running deficits for several months with the biggest occurring in March. Unless we get a wet May that cuts into the building precipitation deficits however, count me as someone that believes a very hot and dry summer is on the way. Yeah, this kind of thing is a little too anecdotal and might need a scientific infusion but I have a sentimental weakness for some of that stuff and it was a good way to end another season of blogging. 

Hope everyone made the best of the season under some trying circumstances. Hope everyone enjoys their summer and we will talk again late next fall !!

Wednesday, April 14, 2021

Melt most of our snow, open Rt 108 to Smuggs and like magic, the heaviest accumulating snow event for the high country appears !

We are about halfway through April 2021 and daytime temperatures are averaging almost 8 degrees higher than all of April 2020. The outlook for the coming 10 days does look a bit cooler relative to average and won't include another succession of 70-degree temperatures but it won't change a final outcome of a warm and dry month. The latter characteristic is of growing concern going into a summer that I already expect will be on the dry side. I don't update the blog in mid-April for dry weather however, I update for snow and a storm that could prove to bring the largest accumulating snow of the season to Sugarbush and Mad River Glen this season. And it wouldn't be right if it didn't involve another late inning northward shift. 

We are obviously way out of our climatological winter and the storm in question is not working with any impressive area of polar chill.  But this is an impressive storm and a supportive, very blocked weather pattern and we have a northward shift so its game on. As of Wednesday (April 14), we already have a closed upper level low slowly advancing eastward out of the western Great Lakes and now feel very good about an infusion of sub-tropical synoptic energy early Thursday. Temperatures will still be mild for most of Thursday across the MRV and all of Vermont for that matter but as the storm phases and deepens throughout the day, it will manufacture its own kind of cold air, the kind that allows it to snow in mid-April. So, we can expect rain during the afternoon and evening hours and then start seeing some snow, first at high elevations and eventually even at lower elevations during the evening hours, just as it begins to get dark. The best zone for snow is in Vermont but still appears to be in central and southern Vermont and into the Berkshires for now. This favorable snow zone however has been shifting north with each succession of model runs however and the MRV high country is only about 40-50 miles away from the bullseye zone as of Wednesday afternoon.

Because the cold air is very "storm manufactured", the snow will be very gloppy in nature, even at high elevations. Atmospheric cross-sections reveal very little change in temperature with elevation but there will be some (heck there is always some). Taking some of the high res data at face value would indicate that temperatures Friday morning are 32-34 below 1500 feet and maybe 28-30 above 3000 feet. So, we could at least get close to some drier snow if one can themselves up toward the summits. The snow Thursday night into Friday is no joke however. Can you believe this could be the biggest accumulating snow event of the season ? I will never not welcome such a storm but there's a little SMH in all this since we just saw one of the earliest Rt 108 >Smuggs opening in a while and are currently working with very limited open skiable terrain in VT. Mother nature doesn't care however, it will do what it wants to do. In valley locations up to the base of MRG this appears to be a 4-12 inch event, but above 2000 feet, 10-20 inches is looking more and more likely. In this best "snow zone" across central and southern Vermont, upwards of 2 feet or more appears likely in some of the high elevation areas. The snow is expected to be heaviest early Friday morning and taper off to snow showers or snow flurries by late Friday afternoon. 

The storm will also put an end to a rather impressive run of mild weather that we saw through much of early April. The weather pattern appears to be a bit more unsettled generally and more seasonable on the temperatures side. This essentially means a bunch of sub-freezing nights and above freezing days. The upcoming storm will  help with our precipitation deficit and models indicate that we could sea a bit more in the next 10 days though there are no glaring indications of heavy rain or snow after Friday. 

Enjoy the spring snow

Wednesday, March 31, 2021

April Fools storm update and a cooler outlook for the first two weeks of the month

 So, one of the better snow events over the past month continues to headline the forecast for the start of April. The outlook for the first 2 weeks of the month generally continues to cool but the April 1-3 period is almost certainly going to be the coldest, most wintry period of the month with not just snow but powder snow falling not only over the high country but low lying locations as well. 

Mild weather and some much needed rain is expected for Wednesday evening. Many locations in northern Vermont are still below an inch of for the month and running deficits now can cause problems later in the summer. The rain Wednesday evening should place many of those same locations above an inch for the month but of more significance is a regenerated area of low pressure that is expected to take shape near Cape Cold early Thursday as temperatures turn abruptly colder in Vermont. Looking at some atmospheric soundings, rain could actually turn to a period of sleet during the morning and then moderate to occasionally heavy snow during the midday and afternoon hours. Temperatures will drop close to the freezing mark during the morning but continue to fall during the afternoon supporting the aforementioned colder snow consistency throughout the MRV. The steady snow will taper to snow showers Thursday night and I still like the of a 4-8 inch grand total by Friday morning at Mad River Glen and Sugarbush. From Stowe, northward to Jay Peak, 6-10 inches appears more likely. Friday is a blustery, cold almost January-like day with temperatures in the teens during the morning and mostly in the twenties during the day, in spite of some sunny intervals. You never say never in northern New England but I would guess Friday is the last true sub-freezing day we see this winter. The outlook does look colder as I mentioned beyond April 3 but not that cold. 

We can expect some strong winds of 20-30 mph across high elevations late Thursday and into Friday and although that will subside over the weekend, the wind will not die out altogether. Temperatures are also expected to moderate more gradually, only readings the high 30's Saturday and 40's on Sunday. Our expected weather pattern has shifted a little thanks to the reemergence of an old friend, a blocking structure across the Labrador Sea and Davis Strait region. This is similar to a feature that dominated the weather pattern for 6 weeks in December and through a good part of January this past year. In this case, storms are expected to tunnel underneath this structure and the question relates to what particular region of mid-latitude North America gets impacted by such storminess. It could be northern New England which would mean perhaps an elevation sensitive snowfall and some needed precipitation or it could be further south impacting the Mid-Atlantic states. In either case, the weather looks cooler in Vermont though not necessarily cold. A storm is retrograde westward late this weekend into early next week, ultimately positioning itself south of Nova Scotia Monday and Tuesday before finally being swept eastward. The presence of this feature will keep wind and some cloudiness over Vermont in this period and will also keep temperatures generally in the 40's most days. Storminess, if we get it, could arrive by late in the week but models are very split on that idea. It looked unlikely in the last update however, at least through April 9 and it's at least possible now. Beyond April 9th, much of eastern North America looks normal to cool which is certainly a change relative to what was expected in early April a week ago. 

Going to do one more general update (unless a storm shows up) early next week so I'll wish everyone a happy Easter now and thanks for the outpouring a well wishes in the last update. Was very surprised to see so many responses there and I certainly appreciate it.