Uncertainty remains regarding specifics but snowfall over the next 8 days looks better beginning early Christmas Eve

 The White Mountains got a bit of light snow Wednesday morning and parts of interior Maine saw a decent snow event from the mostly offshore storm conglomeration. Vermont was in the unlucky zone this time and aside from snow showers on Wednesday/evening night, our high country under-performed. Our natural snow prospects are looking up generally with several chances emerging or coming into focus beginning early on Christmas Eve. We have a concern around the New Years holiday but I would be inclined to take the "over" on a foot of new snow before Near Years 2022 and the pattern looks favorable for more in the first week of 2022. 

The Hudson Bay is now 80 percent frozen and this is allowing stronger arctic air to infiltrate eastern Canada. Some of that chill will successfully make inroads into northern Vermont Wednesday night into early Thursday and as a result, we can expect the coldest day of the season so far with temperatures holding in the teens across the high country and struggling to 20 in the Valley. Clouds and an area of light snow are expected early on Christmas Eve. The best chance for 2-4 inches appears to be over the Berkshires or southern Vermont but this zone of snowfall has looked better and better over time and 1-3 inches looks likely the MRV as opposed to just possible with all of this coming before the ski day. Of even more interest is what appears to be a healthier area of moisture associated with an approaching storm system late on Christmas Day into Sunday the 26th. Models are having trouble establishing a clear consensus on the outcome here but the American model has, for several runs, indicated a significant snowfall for much of northern Vermont. I want to be optimistic but taken in the aggregate, a significant storm of over 10 inches remains just possible but a light snowfall late on Christmas Day into early on the 26th of at least 3 inches appears likely. The forecast is likely to evolve a bit so stay tuned. 

Interestingly, the models not on board with a storm on the 25th/26th are on board with snowfall Monday/Tuesday the 27th and 28th. So it appears to be a situation where the various forecast simulations are having trouble resolving the complicated interaction of jet stream shortwaves and areas of moisture and surface features. In spite of this uncertainty however, we have the right ingredients for snowfall through December 30th and are in a good spot for snow in a fairly wide range of scenarios. Just a matter of determining the where and the when. 

Where I have some concern is the period around New Years. The big picture jet stream view has a blocking feature in the Hudson Straight around this time while a ridge in the southeast United States experiences from temporary strengthening. I can recall how the Christmas 2020 forecast evolved into a debauchery and will note some similarities. We don't want any storm getting sucked into central Canada to the west of that block and would much prefer a storm that would tunnel through all of that and allow cold air to remain entrenched over Vermont. Ensemble data would seem to suggest a latter scenario for now but I am little nervous. 

Meanwhile the bitterly cold air over North America will maintain an intense focus on western Canada and portions of the Pacific Northwest both around and after Christmas. Most of the big weather headlines that are winter related will be focused on that region of North America but some of that cold is indicated to stretch eastward into early 2022 and impact parts of New England. If we can avoid a New Years thaw, we would be set up well for a productive start to 2022. Congratulations to all for rounding another Winter Solstice. We can never be too certain about weather conditions but we can say that the next 6 months will feature increasing amounts of light so enjoy !

Even as milder weather controls much of the eastern United States this Christmas, winter maintains a grip on Vermont with several chances for light snow in the coming week

A couple runs of the European Model was suggesting a widespread torch on Christmas Eve and Christmas Day over portions of the Plains, Midwest and Southeast. On the heels of the out of season weather last week and last years Christmas monsoon, this caused a bit of a stir in the social media weather back and forth. Though the weather has trended in the "not as cold" direction over Vermont, our outlook still appears pretty solid for winter weather through the holidays. Our biggest concern involves the track of a  potential weather system on December 28th, but taken at face value, sub freezing temperatures appear likely to hold their ground, especially above 2000, where most of us actually ski. 

A clipper system, well to our north will give us a distant hand wave but aside from some flurries or very light snow, we won't see much of anything. If you're desperately looking for that 1-3" then head toward the Canadian border but most of Vermont will just see intervals of clouds and sun on Tuesday with temperatures generally in the 20's. We have better chance of snow early on Wednesday when a strong sub-tropical system off the Atlantic coast begins to team with a stronger polar/pacific impulse. An area of snow will be expanding across eastern New York and interior New England and although the best area of snow clearly appears to be Maine, several hours of light snow is likely across the northern Vermont high country before dawn or at least before the ski day Wednesday. This appears to be a 1-3 situation but additional changes are possible. 

The cold weather will hold its ground across Vermont on Christmas Eve/Day but the milder air will make a big push northward and that process will create a zone of moisture and precipitation across the northeast. In Vermont most of that will fall as snow, so long as the moisture makes it far enough northward before decaying as it runs into dry airmass stationed to our north. The timing of all this appears to be either late on Christmas Eve or early Christmas Day and would amount to another light accumulation for the Christmas ski day if it happens. 

The big picture outlook has trended toward the less cold side. The main reason for this has to do with the bitterly cold air having a specific focus on western North America particularly western Canada. Meanwhile, a blocking ridge will migrate from central Greenland to the Hudson Strait well north of us. Oddly enough (or not so oddly), this pattern appears similar to the jet stream configuration that prevailed in the weeks following Christmas last year. Though much of the Vermont high country remained sub freezing throughout the period and even scored some decent snowfall, temperatures were not bitterly cold and continued to average above normal relative to climatology. 

As mentioned in the opening, there is evidence of another organized storm impacting our region around the 28th. We have what appears to be a soft area of cold weather dominating much of interior New England and eastern Canada around this time and although in the case of Vermont, milder air will make another run at the region, ensembles are suggesting that sub-freezing temperatures hold. This means that the forecast for the holiday week should consist of temperatures in the 20's and 30's for highs and mostly teens for lows. Chances for snow or wintry precipitation are on the aforementioned Tuesday the 28th and again closer to New Years.

6-12 for Saturday with a wintry holiday outlook remaining in place

Our reintroduction to winter on Saturday will be exciting with a beautiful powdery snowfall expected to begin around noon and continue at a slow but steady rate through the overnight and into very early Sunday. It is actually a very straight-forward forecast considering. I know some of the model output maps circulating around social media would indicate that southern Vermont is the best spot for this storm. Perhaps, but I would still prefer to be us. We will be in a colder spot with temperatures closer to 20 on the mountain and temperature profiles indicate no threat of mixing - just a cold powdery snow from start to finish with 1-3 inches late in the ski day Saturday and a storm total of 6-12 inches by the start of the ski day Sunday. Flurries will linger into Sunday but the daytime weather will feature some sunshine, blustery and cold conditions with temperatures around 20 degrees. 

We will have additional chances for snowfall late Monday into Monday night (very light) and again on Wednesday into Wednesday night the 23rd. The polar jet disturbance arriving on Wednesday may interact with a stronger sub-tropical feature off the Atlantic Coastline setting up an inverted trough situation and a decent area of snowfall somewhere across interior New England although it will take another day or two to figure out if 1) that actually happens 2) where that actually happens. We will successfully keep temperatures under the freezing mark for an extended stretch, beginning with Saturday's storm and lasting through Christmas; in fact, the actual Christmas holiday will likely feature the coldest weather of the season so far with the phased storm off shore opening the door for a stronger version of arctic air to enter our forecast picture. Having said this, any cold weather should remain in the garden variety category for Vermont with high temperatures in the teens and 20's. The much below normal cold should remain out in the Pacific Northwest for the time being. 

Some of the above dovetails rather nicely into the longer range outlook which continues to consist of winter-like temperatures of a more garden variety and certainly a few chances for snow between Christmas and New Years. The feature in the jet stream that will help keep New England on the more wintry side is a strong area of unsettled weather positioned south of Newfoundland, directly underneath a blocking feature over Greenland. Northwest flow in the jet stream (over us) is generally considered fair-weather flow but a weak ridge in the central United States will try and push storms up in our direction once or twice. We could also attain a bit of colder moisture from the Canadian Maritimes in this setup were we to miss out on a more organized weather system. The colder more wintry outlook remains in place through both holidays right now and certainly no repeat of last year's rainy Christmas debacle. Enjoy the powdery snow Saturday !

Mild stretch ends Friday with 6-12 powdery inches coming late Saturday and colder weather maintaining a grip on Vermong through Christmas

Parts of Nebraska and Iowa that are more used to seeing sub-zero temperatures this time of year are dealing with a massive severe weather outbreak from thunderstorms. Straight line winds of close to 100 and even tornadoes just add to what has been a historic December for weather more typical in April or May. Though we will avoid the thunderstorms on Thursday, we can expect some gusty winds to go along with the very mild 50-plus temperatures, especially during the afternoon and evening. 60-degree readings are certainly possible in valley locations but it will require a few hours of sunshine and that is not what data is indicating at this time.

Colder temperatures will very slowly seep back into Vermont Friday but we can still expect a very mild December day with readings generally above freezing with the exception of the highest summits. Fortunately this will be the last such day in a while with a new very improved regime set to take over, just in the nick of time for the holidays. Saturday's storm is a beauty. A fast moving open wave, so we won't see anything historic but the storm is strong enough and appears poised to track right through our powder alley - the southern New England coastline. Temperatures might be hovering in the high 20's Saturday morning, but will fall into the teens and low 20's once the snow begins around noon and continues into the overnight hours. By Sunday morning, much of northern Vermont can expect a powdery 4-8 inches with 6-12 over the high country. A very nice liftoff event even if it was delayed. 

I had my fears and doubts but it appears as if the cold will mostly win the battle for control of Vermont's weather following Saturday's storm and through Christmas Day. This is terrific news because the risk of another thaw or rain/ice type event was certainly lingering, but we can just push much of that to the south for now. It doesn't look like anything big will come together for Monday/Tuesday, the 21st and 22nd but a polar jet impulse has the capability of bringing both light snow Monday night followed by a reinforcement of colder temperatures for the middle of the week. There is an interesting sub-tropical feature that will be spinning its wheels along the Gulf Coast at this point and its interaction with the series of polar jet impulses remains a question. It may pass innocently offshore with a whimper late next week, but it could phase either slightly offshore or closer to the coastline with a stronger polar jet impulse poised to enter our forecast picture on the 23rd into Christmas Eve. Either way, it provides us with another opportunity for at least some light snow and a slight chance for something bigger. Temperatures on the mountain should remain below the freezing mark throughout next week and should top out in the 20's and 30's across the valley locations while falling into the single numbers and teens during the overnights.

Our new and improved weather pattern continues to look gradually better with each passing day. The bulk of the cold and storminess still appears focused on the Pacific Northwest around Christmas, but this area of cold appears to seek a broader, flatter influence over lower North America. It will essentially get squeezed, pinched and almost hyphenated over southern Canada and the northern third of the United States, lodged between two upper air ridges, one in the northern Pacific and another over Greenland. Barring a change, this should equate to some excellent results for Vermont with cold weather remaining in place or even intensifying and a storm track aimed south but not too far south of us. The southeast ridge appears weaker but it continues to lurk over the southern plains, This collection of features should produce a rather fast current of air over the United States and some storminess between the holidays. Just a massive improvement compared to how this all looked a week ago ! Fingers remain crossed.

Next week/holiday outlook continues to show improvement with new snow providing relief as early as Saturday !

The torchy pattern already underway will hit us with 3 big upper cuts. The first having already happened on Saturday with the rain and wind. The 2nd came Monday and was a rather tranquil spring-like Vermont day with plenty of afternoon sunshine and near 50-degree temperatures across low lying areas. The third will come Thursday and continue into Thursday night and will feature more wind, maybe some minimal sun Thursday afternoon and readings as high as 60 in some valley locations. The strong and balmy winds will continue through the Thursday overnight but we appear to be mostly done with the "R" word and the outlook beginning as early as this weekend continues to improve and the holiday period continues to look more and more wintry across interior New England. 

Two very important fundamental changes will be responsible for aforementioned improved outlook. Convective forcing in the south Pacific will continue to work at softening the jet stream and forcing much of the ridging closer to the Arctic. This along with the formation of a large ridge in the jet stream over Greenland will allow much of the arctic air over North America to make a southward push, even within a week ! We haven't eliminated all of our road blocks. The formidable ridge will get pushed southward across the eastern United States but will not be eliminated completely and thus the pattern will take on a classic La Nina look with cold and storminess focused on the west, mild weather confined to the southeast and winter assuming a tenuous grip on the Great Lakes and New England. I'll take tenuous over nothing and with that we can discuss our chances for snow. 

Our first chance comes Saturday in a classic, if you don't like the weather just wait a day - fashion. Temperatures on Friday will be very slow to chill and are unlikely to reach the freezing mark until Saturday when precipitation is set to arrive. We won't have any cold/dry air to work with in eastern Canada but we will have incoming cold behind this system and  this creates a scenario will temperatures will continue to fall late in the day Saturday allowing any mixed precipitation to turn to snow. We have two of the three major medium range computer simulations indicating this event and I am certainly at the point where I think it's more likely than not. What kind of event do I speak ? At least a few inches of snow followed by garden variety cold weather Sunday into Monday.

In addition to the event on Saturday, there are indications of another on Tuesday, the winter solstice and then another right around Christmas weekend. Most importantly (at least to my eyes) is this continued trend to place interior New England on the cold side of this Canadian cold vs southeast U.S. warmth battle. This alone substantially lowers the risk for any rain and above-freezing temperatures of any real significance.

Though weather pattern flip is unlikely by the holiday, winter weather and snow is likely to make a return, at least in some form

 I can't provide any good news for the upcoming week except to reiterate what has already been discussed and amplify on a few themes. We can expect to see sunshine Monday, Tuesday, and parts of Wednesday and Thursday while most of our nights will stay sub-freezing. It will be mild Monday and then very mild late in the day Thursday, Thursday night and into Friday morning. Last I checked, it's pretty hard to blow a building down that hasn't even been built and I am of course speaking figuratively about our snowcover. If clouds do give way to sunshine and wind on Thursday, we could see temperatures approach 60 across low lying areas. If it stays cloudy, it will stay cooler much like it did Saturday but the mild air combined with wind will chew away at any existing snowcover man-made or not. Those snow-eating conditions will continue into Thursday night before cooler weather arrives during the day Friday. It's a very mild week overall but we've been anticipating this for a while and although a pattern flip still isn't imminent, the outlook continues to improve starting as early as the December 18th-19th weekend. 

There are a few important bullet points to keep in mind. 1) Climatology in late-December Vermont is quite different than early-December Vermont. Marginal patterns can be productive by late December. 2) The pattern doesn't look ideal but the weather pattern continues to look less and less unblocked by the winter solstice (sorry about the double negative there but trying to apply the most accurate adjectives). 3) The coldest weather in the northern hemisphere continues to be heavily focused on our continent, opening the door for arctic air to provide a much needed assist in this marginal overall weather pattern. 

The bottom line for the days leading up the holiday and beyond: The focus of the cold appears to be on western North America just as it did a few days ago but with the jet stream at high latitude looking more blocked, arctic air appears capable of being a significant player across northern Vermont. We will certainly need it given the continued presence of a ridge in the jet stream in the southeastern United States. The period beginning December 18th and extending through Christmas is likely to feature several chances for precipitation. Though we are unlikely to score victories for every potential event, we will be back in the game which is certainly a big improvement over the upcoming week where we will have "no game". Hopefully we all stayed dry today !

A mostly mild outlook remains in place but I've seen worse !

 I want to start this post on a wintry theme. First, it is wintry thanks to the snow we received Wednesday evening and a couple of beautiful Lake Champlain enhanced snow showers that were nice to enough to present themselves to the Mad River Valley Thursday morning. More generally (and secondly), the region is on the far southern periphery of a very impressive polar vortex that impacted much of central and eastern Canada with severe early December cold. The expansive area of chill never really made a serious run at the United States but it did effectively eliminate all of the warm water in the Hudson Bay, which as of December 9th is a third frozen. Take a look !  

SST Animation

Arctic Ice Coverage - NATICE 

The upcoming forecast is not especially wintry but eliminating bad feedbacks mechanisms will hopefully pay dividends down the road. In the short term, we can expect to enjoy our wintry weather through Friday and perhaps pick up a little light snow from some rapidly northeastward moving warm advection moisture. That snow exit by early afternoon and we can expect temperatures to hover around the freezing mark through Friday night. Saturday still looks to be a torch. Mad River has indicated they want to open the practice slope on Saturday and we can expect low clouds in the morning to give way to a mild and windy afternoon with rain showers moving between 1 and 3 pm. Temperatures are likely to make it well into the 50's in the valley and at least approach 50 at the MRG base so snow conditions should soften accordingly.  It won't be as mild Sunday but it won't be cold either with temperatures hovering in the 30's. Expect both sub-freezing temperatures and wind above 2500 feet. 

The central third of the country appears to be ground zero for next week's mega torch. Mild temperatures will impact Vermont as well but as I mentioned a few days ago, we will mostly remain on the fair weather, front flank of the large jet stream ridge. This means we should see decent amounts of sunshine and it also means cooler Canadian air is likely to keep interior New England closer to normal compared with areas like Minnesota or Wisconsin. Temperatures are likely to climb into the 40's across low lying areas on Monday and might get as high as 50 very late in the week. Most of our nights will be sub-freezing however and the middle part of week will feature sunshine and readings in the thirties. I expect to see a bit of rain sometime late in the week but I've seen rainier and milder thaw's than this one. I like mild weather in the spring but I find record high temperatures in December to be rather soul crushing and I don't think we see those next week. 

There are also signs in the long range that the pattern fundamentals or teleconnection indices will be improving. The jet stream at high latitudes begins to look less unblocked and the AO index appears close to zero as we approach Christmas. All this said, the pattern still favors mild weather in New England through the Winter Solstice and beyond and even if effectively neutralize the AO and partially weaken a Pacific Jet stream, it will take a little while before we can start talking about a sustained stretch of winter weather and cold. I might add that the changes in the jet stream fundamentals actually favor a rather impressive out break of cold across the western North America. I expect some of our favorite ski areas out west to perform very well during this holiday period and into early 2022. 

I did notice that the Chrome internet browser is not letting users on to the blog while other browsers are indicating it is not secure. I will look into this and hopefully we can rectify quickly.