The 2022-2023 ski season has concluded at Mad River Glen and having lasted some distance into April and 114 total days, I can officially declare it a decent year. There was a time not too long ago when it didn't feel that way and after several mid-winter gut punches, we seemed primed to get KO'd, but we clawed our way back, slowly at first, but finally earned ourselves respectable snow season following yet another Ides of March storm. The whole "think snow" mantra might seem tired after so many seasons, but I thought we put in a really good effort in that regard this year and the nearly 200 inches of seasonal snowfall felt pretty darn good.
Meanwhile, didn't seem to take much thinking to receive snow out west. It was an incredible season over most areas west of the Continental Divide, particularly in the states of California, Nevada and Utah. The weather pattern, largely powered by another big negative Pacific Decadal Oscillation index was amazingly persistent, supporting both cold weather and storminess throughout the year. The storms were notable for both their frequency and strength and a slow methodical melt off would alleviate what has been a stressed water situation in the Golden State that only seems to get worse over time. Extra water will also provide California some short term and much needed cheap energy since the state depends on hydroelectric generation, but can't claim this in abundance if water isn't flowing . This was very much another winter season that illustrated the underlying power of the PDO in terms of how it can drive a weather pattern. The 2014-2015 snow season, when portions of southern New England were buried in record snowfall while California was hit with a major drought featured much discussion about the role of AGW in contributing to the growing and persistent drought concerns out west. That year featured a record positive PDO and the weather pattern seemed just as persistent as the one featured throughout the 2022-23 season but in reverse with cold weather and snowfall favored over eastern North America. This recent winter, which featured a 5-month cold season aggregated PDO value of -1.29 actually fell short of the prior season's negative number but still stands in stark contrast to the 2014-15 number of +1.77.Got some PDO values from the last 10 seasons below and a link to some additional info on it here.
The PDO is not the only game in town and one can go back through history and easily find seasons where the weather pattern is not hogtied to PDO values. The recent winter season also featured a moderate La Nina with colder than average temperatures enveloping large swaths of the equatorial Pacific Ocean. La Nina conditions are correlated to PDO conditions though not perfectly and the combination of the two may have been the right ingredient to produce a weather pattern capable of producing so much snow and relative cold, west of the Continental Divide. Below are some selected snowfall totals for ski resorts in the areas discussed and some others.
Alta wins the title for most snow, but almost any location in California saw snowfall amounts approaching 200 percent of normal. Across the east, the few stations I selected in that table illustrate how sensitive this snow season was to latitude. Jay Peak recorded essentially a normal snow season while Stowe, Mad River Glen and Sugarbush recorded respectable amounts yet still what is considered below average by the Onthesnow.com standards. This gives me the opportunity to do a quick opine on ski resort snowfall data which is recorded in a highly unscientific manner leading to amounts that are skiflationary compared to reality. There are several ways this is accomplished but the most sure-fire way to achieve a skiflationary snowfall total is to measure in several locations, record the range and then continue to sum the seasonal total using the high end of that range. I've numbed myself into partaking into this absurdity, justifying the practice with the idea that it will actually get us to apples to apples comparisons though it actually doesn't when ski area opts for honest reporting. This past season, if anyone notices or cares, I actually was partaking in this unscientific procedure and recorded a higher total at Mad River Glen than the mountain actually recorded. My total was actually closer to Sugarbush's seasonal amount of 195". It's not especially important to me but I do think mountain ops at MRG missed 10-15 inches in November and then somehow managed to short itself another 10 inches in the March storm by adding 35" to 135" and getting 160" instead of 170". All good however and I certainly respect the fact that MRG reports ranges as opposed to partaking in skiflation and hopefully this digression helps folks understand how all the numbers, my own summations, Sugarbush's and MRG's could be all so different.
The same weather pattern that resulted in all the snow across California, Nevada and Utah was also responsible for the persistent warmth across the east, especially southeast US. The mild weather may have appeared blunted in northern New England but every month was above average relative to even new, warmed 30-year averages (The 1991-2020 average are materially warmer than 1981-2010 and I'll let the reader speculate as to the reason) and January was the warmest ever recorded across most of New England. Arctic air certainly had a North American presence in every month except January (more on that later), but was either focused on western part of the continent or at higher latitudes in Canada. Populated areas of the northeast saw two big but very short-lived outbreaks of cold, one occurring in the days prior to Christmas while the other slammed the region in early February. Vermont was ground zero for the second and much of the state saw the coldest wind chill temperatures in several years. In the southeast U.S. winter essentially ended after the Christmas outbreak of cold. Atlanta, GA saw temperatures plummet to 9 degrees on Christmas Eve and never saw sub-20 degree readings again and only a handful of mornings were even below freezing. Needless to say, this weather pattern took a tremendous toll on the ski season in the Mid-Atlantic where it was a struggle to keep snow on the ground and terrain open.
To reiterate, the weather pattern manage to induce above normal temperatures every month of this past cold season though there were variations on this theme. The November warmth was powered by the first 11 days which featured 4 days of 70-degree temperatures across valley locations. Colder air arrived on November 13 and much of the rest of the month featured early season arctic air and several inches of wet snow fell on November 16th. As the month progressed it seemed apparent that the weather would get interesting in December with indications of a large high latitude blocking structure emerging over Greenland powering a big expected drop in the North Atlantic Oscillation (NAO). Some of this indeed happened, but much of the blocking ultimately set up farther west over the Davis Strait early in December and then transitioned to the Arctic regions near the top of the Yukon Territory later in the month. The shift in this blocking set up basically meant that much of the winter weather fireworks which could have occurred along the east coast, happened farther inland or west. This includes Buffalo, NY which saw one massive outbreak of heavy lake effect snow during the cold weather in mid-November and would later see a historic wind-driven lake effect snow storm with the cold outbreak before Christmas.
Vermont saw a rainy start to its December with much of the cold focused further west. It appeared for a time like the mild weather would persist through the 2nd week of December but the blocking won out and not only did we get a colder week, but got some big snow to go along with it with most of the snow falling on Friday December 16th, setting us up for a proper weekend opening. The storm looked ominous, initially taking aim at the eastern Great Lakes and threatening to track toward the St Lawrence Valley, but the jet stream structure helped ensure that the storm would reform on the eastern seaboard in a much more advantageous position; in fact, it turned out nearly perfect and produced nearly 2 feet of snow, one of the best events of the season for Mad River Glen. Several days of sub-freezing temperatures in the wake of that storm brought some of the best December skiing since 2018. It certainly looked like we could keep it going for the duration of the month as a massive surge of cold weather, the strongest of the season in many parts of the eastern United States, enveloped a broad swatch of the continent on and just before Christmas. The cold wasn't especially severe in a relative sense across northern New England but temperatures remained below freezing through early December 29th and it was then that the weather pattern broke and the New Years holiday came in with some very mild air.
The scouring of the cold in the days after Christmas was dramatic and remarkable considering the geographical scale. By New Years 2023, most of the North American continent was mild relative to climatological averages and there was a glaring absence of arctic air. The weather pattern was making plenty of news but for the wrong reason. Anytime we hear about an "atmospheric river" when describing the storminess across California, it can't be good for winter weather fans in the eastern United States and it certainly wasn't. The support for cold weather in mid-latitude North America collapsed by early January using any number of teleconnection indicators, but the EPO in particular, which is a measure of the strength of the jet stream in the Pacific Ocean proved particularly problematic. Powerful storms, one after the other, unleashed fury on the west coast dumping over 200% of normal rainfall on the Bay Area. A colder version of this weather pattern would reemerge later in the season but the January setup actually featured relative high snow levels in the Sierra Nevada Mountains and I certainly remember one Tahoe based ski area shutting a lift down for flooding with that image going viral on social media.
The first 18 days of January was probably the worst period of the season around Mad River Glen. The December snowpack slowly eroded and it was an ugly scene with bare ground very visible over our valley locations. We saw some rain, ice a bit of wet snow here and there and many days with temperatures above the freezing mark though it never did reach 50 degrees. The mild weather, particularly during the overnight hours helped power the month to one of the warmest January's ever recorded but as it turned out, it wasn't the worst January I've ever seen for skiing. As we moved into the middle of the month there were promising signs with neutralizing teleconnection indicators though arctic air remained very bottled up in Siberia where there as news that temperatures were the coldest in 50 some odd years. There was no such cold in Vermont, but the setup for storms was very good and we scored a trifecta on new snowfall over the span of just a week. Steady snow on the January 19th and into the 20th to the tune of over a foot and another 8-14 inches followed late on Sunday January 22nd into Monday the 23rd. The best storm in this period appeared to be lined up for Thursday January 26th and the snow indeed came, but like so many La Nina powered winter weather events, so did the layers of warm air. Following several inches of snow, we saw mixed precipitation and even a brief period of rain right before first chair. The upper mountain survived the onslaught of warmth in one piece, but a lasting memory from that event will be driving across the valley and seeing temperatures start at 26 and then soar to 39 by the time I hit the MRG base. Heard my name mentioned in a less than flattering light (though not too bad) in the lodge that morning but there wasn't too many complaints as the day progressed with that rain changing back to snow and then heavy snow as the Champlain Oragraphic Enhancer came to life and deposited another 10 inches on the mountain. By Friday, January 27th, the skiing and the general mood was terrific and additional snowfall during the weekend and in the early part of the next week certainly didn't hurt.
As the snow piled up across northern Vermont late in January the arctic air began to rebuild across Canada and as it turned out, our neighbors to the north saw a much colder month of February than January. Arctic air also plunged into the snow covered areas of the west, but in the best traditions of La Nina, struggled to maintain any grip on the Mid Atlantic and Deep South. Over New England, it was a colder month but it was powered by one massive outbreak of cold weather on February 3rd-4th with temperatures plunging to 20 below or colder and wind chills exceeding -50. Mt Washington made headlines during that arctic invasion by recording the lowest wind chill ever measured by an instrument in the United States. I phrase it this way because assuredly there have been colder wind chills that haven't been recorded by an instrument. Unfortunately, the cold on February 4th retreated into Canada and mild weather consumed interior New England during the middle part of the month. We were fortunate not to receive a heavy rain event but the snow eroded nonetheless leaving much of ski country in need of more natural snow to save the season.
And then suddenly, the tide turned in our favor. Arctic air managed to push southward into interior New England on February 22nd setting up a nice garden variety overrunning event for February 23rd when cold powdery snow fall over the mountains. Snow showers on the last weekend of February turned into an added bonus and the March outlook continued to improve with blocking showing up at high latitudes after a nearly 2 month absence. As it turned out, the weather pattern partially gravitated toward a more "persistence-based" outcome which in this case means that the configuration of temperature anomalies in North America in March bore a close resemblance to what happened in prior months. It did stay colder however and when the storms came, northern Vermont received snow. We started March with a couple of lighter snowfall events but it seemed almost inevitable that all of the weather drama would revolve around the Ides of March or March 13-15 dates like they always seem to. One again,the calendar worked its magic! There were indications of a storm well in advance that included several different advertised model simulated scenarios. The weekend prior to the storm, models shifted much of the action southward with a slow moving and exploding coastal low remaining south of Cape Cod. Higher resolution model data seemed to confirm this trend and there were stunning indications that much of northern Vermont might struggle to receive any snowfall from this storm. It was all part of a plan though, like a Game of Thrones season, but one with a happy ending. The stage was set for a northward shift and gradually one began to happen. All kidding aside however, it was a terrific illustration of why it is important to consider everything when putting together a forecast and many times the best information is the one coming at you with the most consistent output. Southern Vermont did ultimately get the bullseye initially advertised but northern Vermont performed exceptionally well from this bombing storm that indeed consolidated its energy north of Cape Cod. It was the appropriate finale to this multi-week stretch of favorable weather because the storm managed to, in some ways, resemble some of the other storms over the course of this season only this one bombed harder and produced more snow over a longer stretch of time, 35 inches to be exact. Remarkably, and much like many of the other events this winter, temperatures were just cold enough to support a drier snow. Across valley locations the snow was wetter and not as much of it fell.
The weather pattern remained stormy and certainly capable of producing more events in the last 2 weeks of March and even into early April but the mountains received only mixed results. Early in April there were hints of wintry weather potential both in the first and 2nd week, but this also didn't materialize. By April 9th and 10th, much of the unsettled weather became detached from the jet stream over the Gulf Coast allowing a round of extraordinarily mild weather to impact Vermont in April. By the time the month is over, 2023 version of April is likely to be the warmest, maybe this young century.
This theme of mild weather and specifically the persistence of it was the most remarkable part of the recent weather season. Every month, even March and December, which had some cold weather advertised, featured temperatures that averaged above the recently warmed 30-year averages across interior New England. In contrast, areas west of the Continental Divide saw persistent cold weather and high snowfall every month. I am certainly not the biggest cheerleader for - PDO winters since they are notorious in their ability to produce multi week stretches of warm and wet weather. It is unusual however for such a pattern to be so persistent, but this particular pairing of what was a moderate La Nina and a very negative PDO seemed to be the magic formula. The mild weather produced a historically awful result for snow-lovers along the I95 corridor from Boston southward. Interestingly however, the weather pattern, though persistent, wasn't amplified enough to obliterate the ski season across northern Vermont; in fact, the weather pattern did have some redeeming qualities for the interior. Given enough cold, the storm track generally cooperated and the mountains got its share. The Mt Mansfield snow stake, which acts as the reserve currency for grading the snow season in northern Vermont, lagged on its snow depth relative to normal for much the season before finally blowing through normal on March 14 and remaining there through the end of the month. It was a satisfying way to finish a season with some ups and downs.
Meanwhile, conditions in the equatorial Pacific have shifted with the La Nina status now eliminated and temperatures in that portion of the ocean now running just a little bit above average. At the same time, we have yet to see the PDO relax. An emerging El Nino has been the consensus forecast for ENSO in the coming months but these forecasts are not always correct. It would also be conventional wisdom to expect the PDO to relax if an El Nino emerges as advertised, but this too can defy expectations. I am certainly ok with a mild to moderate El Nino, but most imporantly I want the negative PDO to neutralize. Sure, we managed to survive this recent winter in ok shape but mild onslaughts are not good for my mental health in winter. I continue to see legitimate articles suggesting El Nino conditions will be more prevalent as climate change progresses and though it strikes me as a viable opinion I am yet to be convinced that a warming earth would favor relative warmth in one part of the Pacific Ocean as opposed to another. Unfortunately, we are likely to find out the answer whether we like it or not.
And that puts a wrap on the 2022-2023 season. We had a decent start, had to endure a few big mid-season body blows before managing to fight our way to a respectable snow season .Cold air was a bit sparse on this side of the continent though we made the most of it, and the most of our 44 N latitude and distance from the snowless coast. Amazingly, next year will mark the 20th season of weather blogging at MRG and we get to celebrate its conclusion with a complete solar eclipse on April 8th. Though I don't have any cloud cover prognostications yet, rest assured that I will make every attempt at providing totally inconclusive and inaccurate predictions way too early. Enjoy the summer everyone !