A healthy dose of mixed precipitation fell over Vermont Sunday night into early Monday and by Monday afternoon, the warmest part of this storm will be behind us. As expected, a coastal low pressure center has formed and was re-concentrating the precipitation across much of New England Monday. Between 6-9 pm Monday evening, the lower troposphere should become cold enough to support all snow across northern Vermont and though the heaviest precipitation will be east of the state, 1-2 modest periods of snow should allow for a couple inches by Tuesday morning New Years Eve. Light snow is expected to then continue through the early part of the day followed by some clearing in the later part of the day. Across the valley locations, temperatures will hover close to the freezing mark from Monday through Monday night into early Tuesday. A little sun Tuesday afternoon will likely boost readings past 35 across the low lying areas leaving only the high country as the only locations to consistently remain sub-freezing. A disturbance associated with the now ancient upper level system (ex Dakota blizzard) will bring clouds and more snow showers back to Vermont Tuesday night, just as we approach the dawning of a new decade. This area of snow showers has some potential and I am fully expecting another accumulation by dawn on New Years Day with snow showers and flurries continuing throughout the day.
In accumulation speak, our expectations are roughly the same but with some fine tuned specifics.
2-4 inches Monday night
0-1 Tuesday morning
Sun Tuesday afternoon
2-4 Tuesday night
1-2 Wednesday
This applies to the high country above 2000 feet. Valley locations will get lesser amounts and gloppier amounts of whatever falls.
We can anticipate a drier Thursday with some sunshine and comfortable temperatures that are again expected to exceed the 30-degree mark. Clouds and moisture will then advance back into the region Friday as low pressure organizes in the lower Mississippi Valley and advances northeast toward the eastern Great Lakes. Some uncertainly remains regarding the eventual outcome of this storm which is expected to impact the region late Friday into the weekend. None of the possible outcomes appears especially appetizing though due to the lack of cold air and a less than optimal storm track. The best outcome for us would be for low pressure to again form along the Mid-Atlantic coastline and confine much of the rain and extreme warmth well to our south. The newly released American model is suggesting such and is indicating a near non-event (precipitation-wise) for northern Vermont. Other indications suggest a bit of rain Friday evening. Colder air Saturday night into Sunday should then allow for another period of snow showers with a possible accumulation.
I continue to think the 4-day period between Sunday January 5th and at least Thursday January 9th has some "wintry" potential. Temperatures should stay well below freezing during this stretch and there have been hints (though inconsistent hint) of a significant snow.
Overall however, the weather pattern through the first half of January continues to look lousy with an "evil empire" type ridge in the Pacific and a very unblocked jet stream in the Arctic regions. The Arctic Oscillation (AO) index which measures the latter is forecast to surge to +3 in about a week and only very gradually subside (if at all) thereafter. We could certainly use some help from a cycling of the MJO, which for the first half of January will remain in some milder eastern North America phases. It won't persist forever, but it is another reason why a more persistent cold and snow outlook across interior New England is not my expectation through the first 3 weeks of January.
Monday, December 30, 2019
Saturday, December 28, 2019
New Years system to produce ! Some basebuilding stuff at least and likely a bit more from snow showers
Temperatures are mild across the state of Vermont as of early Saturday but the news is good with the upcoming winter storm. And yes, I am happy to report we can call it a "winter storm". The weekend weather will not at all be impacted by the upcoming weather system. As noted, Saturday will be mild and feature some sunshine with temperatures up around 40. Sunday will also feature a bit of sun in the morning but more clouds in the afternoon and it won't be quite as mild with temperatures hovering around the freezing mark across much of the northern Vermont high country.
The upcoming storm remains a forecasting challenge but the outlook continues to move toward a colder system overall; enough that, rain should no longer be any part of any forecast vocabulary, at least from the MRV on northward. That said, precipitation type remains a question at times and may depend on the precipitation intensity more than anything else. Such precipitation will arrive within a few hours of midnight Sunday night and thanks to a healthy push of dry Canadian cold weather, temperatures at the surface should be at or below freezing. Above the surface to about 9,000 feet, temperatures appear to be marginal in the period between midnight Monday and noon Monday. Given that, a mix of snow and sleet appears to be the most likely outcome with more snow falling when precipitation is heaviest and more sleet when it's lighter.
The storm as a whole will undergo quite a metamorphosis, making news as a full-blown blizzard over parts of Minnesota and the eastern Dakotas before weakening as it makes its eastern seaboard approach. It will be a slow process, but ultimately, another low pressure system is expected to take shape by Monday evening and gradually move northeast along the New England coast Monday night into New Years eve. We have to consider ourselves quite fortunate if this is indeed the evolution, because this 2nd system will thwart any intrusion of mild air and might even deliver a period of decent snowfall to the region Monday night following what might be a break in the action Monday afternoon (when it should just remain cloudy with temperatures near 30). The initial weakening storm has a large pool of instability that is eventually expected to deliver an extended period where snow showers or light snow can be expected. This period should begin sometime on New Years Eve and extend New Years Day.
At this point, I think its reasonable to expect 2-5 inches of a dense snow/sleet conglomeration early Monday and an additional 4-8 inches of fluffier, elevation sensitive snow New Years Eve and New Years Day. There is more upside potential with the developing coastal system as well. Though not a current part of our expectations, were we to get some of that snow, totals for the storm could approach a foot.
We still are not expecting an arctic cold in the wake of this storm. Temperatures will remain above normal in spite of the snow showers New Years Day and more sunshine will boost readings up toward the freezing mark on the 2nd. More subtropical moisture associated with a disorganized area of storminess will approach Friday and will likely bring some type of precipitation back to the region. Without much in the way of arctic cold to work with, our best hope is that this storminess stays disorganized and thus we might avoid a more assertive push of mild weather.
I still can't speak too highly of the pattern for the first half of Jan 2020, but we can still expect a temporary stretch of cold weather between Sunday the 5th and Wednesday the 8th of Jan. Hopefully there is some room in that window for another snow producing system.
The upcoming storm remains a forecasting challenge but the outlook continues to move toward a colder system overall; enough that, rain should no longer be any part of any forecast vocabulary, at least from the MRV on northward. That said, precipitation type remains a question at times and may depend on the precipitation intensity more than anything else. Such precipitation will arrive within a few hours of midnight Sunday night and thanks to a healthy push of dry Canadian cold weather, temperatures at the surface should be at or below freezing. Above the surface to about 9,000 feet, temperatures appear to be marginal in the period between midnight Monday and noon Monday. Given that, a mix of snow and sleet appears to be the most likely outcome with more snow falling when precipitation is heaviest and more sleet when it's lighter.
The storm as a whole will undergo quite a metamorphosis, making news as a full-blown blizzard over parts of Minnesota and the eastern Dakotas before weakening as it makes its eastern seaboard approach. It will be a slow process, but ultimately, another low pressure system is expected to take shape by Monday evening and gradually move northeast along the New England coast Monday night into New Years eve. We have to consider ourselves quite fortunate if this is indeed the evolution, because this 2nd system will thwart any intrusion of mild air and might even deliver a period of decent snowfall to the region Monday night following what might be a break in the action Monday afternoon (when it should just remain cloudy with temperatures near 30). The initial weakening storm has a large pool of instability that is eventually expected to deliver an extended period where snow showers or light snow can be expected. This period should begin sometime on New Years Eve and extend New Years Day.
At this point, I think its reasonable to expect 2-5 inches of a dense snow/sleet conglomeration early Monday and an additional 4-8 inches of fluffier, elevation sensitive snow New Years Eve and New Years Day. There is more upside potential with the developing coastal system as well. Though not a current part of our expectations, were we to get some of that snow, totals for the storm could approach a foot.
We still are not expecting an arctic cold in the wake of this storm. Temperatures will remain above normal in spite of the snow showers New Years Day and more sunshine will boost readings up toward the freezing mark on the 2nd. More subtropical moisture associated with a disorganized area of storminess will approach Friday and will likely bring some type of precipitation back to the region. Without much in the way of arctic cold to work with, our best hope is that this storminess stays disorganized and thus we might avoid a more assertive push of mild weather.
I still can't speak too highly of the pattern for the first half of Jan 2020, but we can still expect a temporary stretch of cold weather between Sunday the 5th and Wednesday the 8th of Jan. Hopefully there is some room in that window for another snow producing system.
Thursday, December 26, 2019
Adverse overall pattern remains a problem but some good news has emerged in spite of it all
There are no signs that the weather pattern will provide us with any love on the whole but some positive developments have emerged nonetheless, at least relative to what was thrown out in the last update. We still have some milder temperatures to work through over the next few days and this includes just a bit of freezing rain and rain Thursday night into early Friday. Most of the actual ski day Friday will be precipitation-free with temperatures in the upper 30's or low 40's. Visibility should improve a bit for Saturday but temperatures will remain balmy for Vermont, reaching at least 35 most places and upper 20's across the high summits.
Our big weather system remains on-target for late Sunday into early next week. The ski-day on Sunday actually looks rain-free and may even feature some morning sunshine. Temperatures will remain on the mild side of average (30's mostly) and minimal wind should make for a comfortable day on the hill. Snow will be falling with this system Sunday but mostly over central and northern Minnesota. The news is not all bad with this weather system however. Though precipitation will arrive as rain on Sunday evening, the initial snow-producing low pressure system over Minnesota & Wisconsin will begin to dissipate and so will the northward push of mild air up the eastern seaboard. Actually, it will be the colder, drier air that will battle back Sunday night and re-configure our temperature cross section in a more favorable direction by the early to middle part of Monday. Precipitation is likely to then change back to snow and the question relates to how much available lingering moisture will fall as snow from midday Monday into New Years Eve. Quite possibly we could receive several inches across the high country before the clock strikes 2020 but the jury remains out regarding very specific amounts.
Though this aforementioned storm appears colder for us, it remains devoid of series arctic chill both as the event is ongoing and in its wake on the first two days of the year. Snow showers and flurries will linger into New Years Day but only with temperatures within a few degrees of freezing during the day and 20's during the night. The summits should be cold enough throughout for any accumulating snow to be powder. The lack of cold air will present another challenge when the next storm impacts the region very late next week. It will require a very optimal track for a snowy result across Vermont and there are growing indications that the result might be something other than snowy. A lot can happen and change in over a week so stay tuned on that.
As mentioned, I can't speak fondly about the overall pattern. It remains unblocked at high latitudes and ripe for an easy surrender to an intense Pacific Jet stream. As mentioned in the last update, some of the most intense cold across northern hemisphere will at least remain over Alaska and both northern and western Canada. Close enough at least to remain a peripheral player for the first half of January even though it will hardly dominate. Ensembles are showing stronger indications of a decent cold surge beginning around January 5th with below normal temperatures prevailing through the middle part of that first full week of January. Any storm in that time frame would be snow I should think but this is way too far out for such things like promises or details.
Our big weather system remains on-target for late Sunday into early next week. The ski-day on Sunday actually looks rain-free and may even feature some morning sunshine. Temperatures will remain on the mild side of average (30's mostly) and minimal wind should make for a comfortable day on the hill. Snow will be falling with this system Sunday but mostly over central and northern Minnesota. The news is not all bad with this weather system however. Though precipitation will arrive as rain on Sunday evening, the initial snow-producing low pressure system over Minnesota & Wisconsin will begin to dissipate and so will the northward push of mild air up the eastern seaboard. Actually, it will be the colder, drier air that will battle back Sunday night and re-configure our temperature cross section in a more favorable direction by the early to middle part of Monday. Precipitation is likely to then change back to snow and the question relates to how much available lingering moisture will fall as snow from midday Monday into New Years Eve. Quite possibly we could receive several inches across the high country before the clock strikes 2020 but the jury remains out regarding very specific amounts.
Though this aforementioned storm appears colder for us, it remains devoid of series arctic chill both as the event is ongoing and in its wake on the first two days of the year. Snow showers and flurries will linger into New Years Day but only with temperatures within a few degrees of freezing during the day and 20's during the night. The summits should be cold enough throughout for any accumulating snow to be powder. The lack of cold air will present another challenge when the next storm impacts the region very late next week. It will require a very optimal track for a snowy result across Vermont and there are growing indications that the result might be something other than snowy. A lot can happen and change in over a week so stay tuned on that.
As mentioned, I can't speak fondly about the overall pattern. It remains unblocked at high latitudes and ripe for an easy surrender to an intense Pacific Jet stream. As mentioned in the last update, some of the most intense cold across northern hemisphere will at least remain over Alaska and both northern and western Canada. Close enough at least to remain a peripheral player for the first half of January even though it will hardly dominate. Ensembles are showing stronger indications of a decent cold surge beginning around January 5th with below normal temperatures prevailing through the middle part of that first full week of January. Any storm in that time frame would be snow I should think but this is way too far out for such things like promises or details.
Tuesday, December 24, 2019
Not a ton of Christmas cheer in this update as we continue to fight a worsening winter weather pattern
Our forecast picture took a few uppercuts over the past few days. In the big picture, the prevailing negative fundamentals, the biggest of which being an AO and EPO index continuing to gain positive strength, are finally playing a stronger role in the regions weather locally and the forecast going forward. Rubbing a little salt in the wound is the forecast for late week which provided us with a bit of a head fake over the weekend. As of now however, much of the light snow that was beginning to appear likely Thursday night appears gone. We will have sub-freezing temperatures, good visibility, tolerable amounts of wind and some sunshine both on Xmas and on Thursday the 26th, but any light snow on Thursday night appears inconsequential (or end up falling as a wintry mix) and the milder temperatures which appeared to be only a miner threat for Friday, now appear likely with temperatures across much of the high country climbing above freezing.
Critical questions and potential problems have arisen after a tranquil Saturday the 29th. There are two major systems that could impact the east coast between Sunday 12/30 and Friday 1/3 and there are justifiable concerns regarding the first of these storms given the lack of arctic cold support. Both warm air and a lot of moisture are expected to surge northward ahead of an advancing area of low pressure Sunday in the Great Lakes region. The eventual trajectory of this storm remains a question, but if the storm tracks north of the St Lawrence Valley, it will be a disastrous wash-out across the entire state Sunday night into Monday. There are indications that the low pressure area in question travels on a more southern route, potentially re-energizing itself off the eastern seaboard. This would be a much better result but given the lack of available cold, even this result might include a bit of rain late Sunday at the onset of this event. Though colder weather is expected to return to Vermont Monday, it's Pacific Ocean air and will thus consist of well-above average temperatures. Lingering amounts of both moisture and instability could set the stage for a decent period of snow Monday but such an occurrence would be better given the latter more southern track of this storm. Either way, snow showers should persist into at least early Tuesday - New Years eve.
The longer range outlook is getting double-whammie'd by the very unblocked jet stream in the Arctic and a corresponding tight and ferocious jet stream in the Pacific (positive AO, EPO). A typical Vermont January is certainly capable of performing even in a marginal pattern; in fact, sometimes the marginal pattern outperforms a polar vortex type scenario where storms and moisture are suppressed too far south. This double-whammy is tough to overcome however, even in Vermont. If there is anything to hang our wintry hats on, its the fact that much of the most intense arctic air across the northern hemisphere will be positioned on the North American side as opposed to the Eurasian side. Though much of it will be across Alaska and NW Canada, perhaps some can find its way into select northern U.S. climates such as the interior NE. That's the positive spin admittedly but there's a negative result to this equation consisting of a forecast dominated by a much stronger torch for the first half of January. Again, that's not the indication yet but it's certainly a risk.
In the meantime, that 2nd storm discussed 2 paragraph's above appears to have an impact period between January 2nd to January 4th in Vermont if at all. Though it appears to be a colder storm for now, and a deeper east coast jet amplification, a lack of arctic cold will keep temperatures on the above side of average. We just have to hope that the lack of influence from the polar jet stream might provide the opportunity for more action along the east coast of the cyclogenesis/bombogenesis variety.
Critical questions and potential problems have arisen after a tranquil Saturday the 29th. There are two major systems that could impact the east coast between Sunday 12/30 and Friday 1/3 and there are justifiable concerns regarding the first of these storms given the lack of arctic cold support. Both warm air and a lot of moisture are expected to surge northward ahead of an advancing area of low pressure Sunday in the Great Lakes region. The eventual trajectory of this storm remains a question, but if the storm tracks north of the St Lawrence Valley, it will be a disastrous wash-out across the entire state Sunday night into Monday. There are indications that the low pressure area in question travels on a more southern route, potentially re-energizing itself off the eastern seaboard. This would be a much better result but given the lack of available cold, even this result might include a bit of rain late Sunday at the onset of this event. Though colder weather is expected to return to Vermont Monday, it's Pacific Ocean air and will thus consist of well-above average temperatures. Lingering amounts of both moisture and instability could set the stage for a decent period of snow Monday but such an occurrence would be better given the latter more southern track of this storm. Either way, snow showers should persist into at least early Tuesday - New Years eve.
The longer range outlook is getting double-whammie'd by the very unblocked jet stream in the Arctic and a corresponding tight and ferocious jet stream in the Pacific (positive AO, EPO). A typical Vermont January is certainly capable of performing even in a marginal pattern; in fact, sometimes the marginal pattern outperforms a polar vortex type scenario where storms and moisture are suppressed too far south. This double-whammy is tough to overcome however, even in Vermont. If there is anything to hang our wintry hats on, its the fact that much of the most intense arctic air across the northern hemisphere will be positioned on the North American side as opposed to the Eurasian side. Though much of it will be across Alaska and NW Canada, perhaps some can find its way into select northern U.S. climates such as the interior NE. That's the positive spin admittedly but there's a negative result to this equation consisting of a forecast dominated by a much stronger torch for the first half of January. Again, that's not the indication yet but it's certainly a risk.
In the meantime, that 2nd storm discussed 2 paragraph's above appears to have an impact period between January 2nd to January 4th in Vermont if at all. Though it appears to be a colder storm for now, and a deeper east coast jet amplification, a lack of arctic cold will keep temperatures on the above side of average. We just have to hope that the lack of influence from the polar jet stream might provide the opportunity for more action along the east coast of the cyclogenesis/bombogenesis variety.
Sunday, December 22, 2019
Not a terrific looking weather pattern to finish 2019 but it could nonetheless get interesting both in the near term and into the new year
Fundamentally speaking, there are an increasing number of adverse variables dictating the weather pattern across North America. This of course refers to the lack of support for cold and snowy conditions in Vermont as we approach another Christmas holiday. With that said, the short term weather forecast hardly looks that terrible and there are no glaring indications of a sustained blowtorch as we approach the end of 2019 and move into the early part of 2020. Instead, the pattern, though certainly not cold, appears at least capable of producing 1 or 2 interesting storms.
As mentioned the near term only consists of a mild Monday. Colder is is expected to arrive on Christmas Eve and we are not expecting any rainfall. Actually, much of Christmas Eve and Day appear to be pleasantly tranquil with at least partial sunshine and good visibility. It will be a little blustery Christmas Eve with winds around 10-15 mph but we've certainly encountered worse.
The last update discussed the possibility for snow late on Christmas Day into the 26th. We can upgrade the possibility for snowfall but we won't see any until late on the 26th. At that point, the minimal amount of cold air entrenched across interior New England should provide the overrunning surface necessary for a period of snowfall. Though snow could start as early as Thursday afternoon, it will likely be the Friday ski day which benefits the most from this. We have yet to see a total convergence of model output regarding this event but I'll call it a 60 percent chance we see a few inches Friday morning. At that point there are more diverging indications of what might occur with some indications that milder air could encroach on northern Vermont and other indications that interior New England remains cold through the start of the weekend. Following the mild start to the upcoming week, the biggest risk for a warm day and any mixed precipitation or rain appears to be either Friday 12/27 or early Saturday 12/28 though again, this is not yet conclusive.
If you follow the weather even just somewhat as religiously as I do, you might have heard about the persistent warmth in Alaska. Parts of central and northern Alaska have yet to record a below normal month in 2019 and have spent alarming amounts of time at or above record level temperatures. Over the next two weeks however, this recent trend will get thrown on its head as intense cold will settle over the state and remain there through the start of 2020. Typically, cold, arctic air in Alaska corresponds to a lack thereof in the more southern sections of North America and I expect this to be no exception. Alaskan cold also often corresponds to a more vigorous jet stream in the Pacific and ensembles continue to suggest an intensification here. Its looking more and more like an "Evil Empire" unfortunately and if I were to look the weather pattern in the eastern Pacific in isolation, I might expect a full blown blow torch across eastern North America. But the ensembles, as they have done for days, are not suggesting that at least as of yet.
There is a threat for the aforementioned warm day on the 27th or 28th but colder weather, possibly accompanied by some snowfall is possible on the 29th and 30th. After that, more mild air thwarting storminess appears likely with continued strong hints of some sort of major jet amplification along the east coast very early in 2020. Given the arctic cold in this pattern, any storm could push mixed precipitation, rain or warm weather into Vermont but at least we have a puncher's chance in a pattern where sometimes we would not.
As mentioned the near term only consists of a mild Monday. Colder is is expected to arrive on Christmas Eve and we are not expecting any rainfall. Actually, much of Christmas Eve and Day appear to be pleasantly tranquil with at least partial sunshine and good visibility. It will be a little blustery Christmas Eve with winds around 10-15 mph but we've certainly encountered worse.
The last update discussed the possibility for snow late on Christmas Day into the 26th. We can upgrade the possibility for snowfall but we won't see any until late on the 26th. At that point, the minimal amount of cold air entrenched across interior New England should provide the overrunning surface necessary for a period of snowfall. Though snow could start as early as Thursday afternoon, it will likely be the Friday ski day which benefits the most from this. We have yet to see a total convergence of model output regarding this event but I'll call it a 60 percent chance we see a few inches Friday morning. At that point there are more diverging indications of what might occur with some indications that milder air could encroach on northern Vermont and other indications that interior New England remains cold through the start of the weekend. Following the mild start to the upcoming week, the biggest risk for a warm day and any mixed precipitation or rain appears to be either Friday 12/27 or early Saturday 12/28 though again, this is not yet conclusive.
If you follow the weather even just somewhat as religiously as I do, you might have heard about the persistent warmth in Alaska. Parts of central and northern Alaska have yet to record a below normal month in 2019 and have spent alarming amounts of time at or above record level temperatures. Over the next two weeks however, this recent trend will get thrown on its head as intense cold will settle over the state and remain there through the start of 2020. Typically, cold, arctic air in Alaska corresponds to a lack thereof in the more southern sections of North America and I expect this to be no exception. Alaskan cold also often corresponds to a more vigorous jet stream in the Pacific and ensembles continue to suggest an intensification here. Its looking more and more like an "Evil Empire" unfortunately and if I were to look the weather pattern in the eastern Pacific in isolation, I might expect a full blown blow torch across eastern North America. But the ensembles, as they have done for days, are not suggesting that at least as of yet.
There is a threat for the aforementioned warm day on the 27th or 28th but colder weather, possibly accompanied by some snowfall is possible on the 29th and 30th. After that, more mild air thwarting storminess appears likely with continued strong hints of some sort of major jet amplification along the east coast very early in 2020. Given the arctic cold in this pattern, any storm could push mixed precipitation, rain or warm weather into Vermont but at least we have a puncher's chance in a pattern where sometimes we would not.
Friday, December 20, 2019
Holiday to week to start out mild, but Xmas could finish with some snow followed by seasonable winter chill
The base is still thin but at least it looks like winter across the MRV this week. Snowfall totals could have been better and I have more or less settled on the idea that this won't be a December to remember. That said, I've seen worse.
Blue sky and terrific visibility is on the way for Saturday skiing or other outdoor adventures. And yes, its nice to get one of those days on the shortest day of the year. Temperatures should top out somewhere in the 20's after starting the day near 5. Not a bad day overall considering the minimal amount of wind. Most of the clouds and moisture associated with a warm front will pass north of the VT/Canadian border Saturday night. Though we could see some flurries, I would not expect much of an accumulation. Sunday will follow with more clouds and a bit more of a breeze but with milder temperatures of up near the freezing on the mountain and above freezing in low lying areas.
As promised, Christmas week will start out mild. That being said, the milder intrusion is short lived and is not expected to be accompanied by any rain and I thus give that a moral victory given east coast climatology. Temperatures are expected to be in the low 40's Monday afternoon but will fall back into the 30's Christmas Eve and back below freezing Christmas Day.
Not much of a chance for new snow on Monday and Tuesday obviously but a scenario does exist late on Xmas day into the 26th for something. I would still consider it a long shot given the limited amount of available moisture, but a stronger push of Canadian air is expected to advance into New England behind a weak wave of low pressure expected to pass just to our south. Aligning the track of this feature with the aforementioned limited area of moisture is a tough ask but not an impossible one. My fair value assessment has a roughly 40 percent chance for a few inches late Christmas Day into the 26th. A modest chance but not yet probable. Temperatures should end the holiday week at seasonable levels which is below freezing. Any clouds should also dissipate by later Thursday, setting the stage for a dry and somewhat sunshiney finish to the holiday week.
There has been a lot of dissension in the longer range outlook. I haven't been especially excited from the standpoint of cold, though the American Ensemble guidance has occasionally suggested we might move toward a cold pattern. On the whole however, the long range Arctic Oscillation outlook appears to be positive indicating a mostly "unblocked" high latitude jet stream. The outlook in the Pacific also suggests an even stronger jet in the Pacific which will further limit any southward advance of extreme arctic chill. It all seems pessimistic but we are entering the time of the year where it's not necessarily such a good thing to get overwhelmed with arctic air. By simply avoiding an all-out torch, it might be possible to garner a few intriguing weather situations out of this upcoming pattern. The subtropical or southern branch of the jet stream appears formidable and multiple simulations seem to suggest the possibility of a big east coast storm sometime during the first few days of 2020. Another 1-2 days of milder weather is also possible in this pattern. Though this appears most likely just before the New Years 2020 this is not etched in stone and models going out that far have shown varying scenarios.
Blue sky and terrific visibility is on the way for Saturday skiing or other outdoor adventures. And yes, its nice to get one of those days on the shortest day of the year. Temperatures should top out somewhere in the 20's after starting the day near 5. Not a bad day overall considering the minimal amount of wind. Most of the clouds and moisture associated with a warm front will pass north of the VT/Canadian border Saturday night. Though we could see some flurries, I would not expect much of an accumulation. Sunday will follow with more clouds and a bit more of a breeze but with milder temperatures of up near the freezing on the mountain and above freezing in low lying areas.
As promised, Christmas week will start out mild. That being said, the milder intrusion is short lived and is not expected to be accompanied by any rain and I thus give that a moral victory given east coast climatology. Temperatures are expected to be in the low 40's Monday afternoon but will fall back into the 30's Christmas Eve and back below freezing Christmas Day.
Not much of a chance for new snow on Monday and Tuesday obviously but a scenario does exist late on Xmas day into the 26th for something. I would still consider it a long shot given the limited amount of available moisture, but a stronger push of Canadian air is expected to advance into New England behind a weak wave of low pressure expected to pass just to our south. Aligning the track of this feature with the aforementioned limited area of moisture is a tough ask but not an impossible one. My fair value assessment has a roughly 40 percent chance for a few inches late Christmas Day into the 26th. A modest chance but not yet probable. Temperatures should end the holiday week at seasonable levels which is below freezing. Any clouds should also dissipate by later Thursday, setting the stage for a dry and somewhat sunshiney finish to the holiday week.
There has been a lot of dissension in the longer range outlook. I haven't been especially excited from the standpoint of cold, though the American Ensemble guidance has occasionally suggested we might move toward a cold pattern. On the whole however, the long range Arctic Oscillation outlook appears to be positive indicating a mostly "unblocked" high latitude jet stream. The outlook in the Pacific also suggests an even stronger jet in the Pacific which will further limit any southward advance of extreme arctic chill. It all seems pessimistic but we are entering the time of the year where it's not necessarily such a good thing to get overwhelmed with arctic air. By simply avoiding an all-out torch, it might be possible to garner a few intriguing weather situations out of this upcoming pattern. The subtropical or southern branch of the jet stream appears formidable and multiple simulations seem to suggest the possibility of a big east coast storm sometime during the first few days of 2020. Another 1-2 days of milder weather is also possible in this pattern. Though this appears most likely just before the New Years 2020 this is not etched in stone and models going out that far have shown varying scenarios.
Tuesday, December 17, 2019
Wintry week to finish cold but some milder air has entered the forecast picture in the days leading up to Xmas
We endured the brief scare that our current December 17th storm might not deliver, but it has provided most of what was advertised and has restored some winter scenery to our beloved Vermont landscape. December will not go down as a particularly arctic month but the coldest weather of the month will nonetheless make its appearance, brought in by a potent jet impulse Wednesday evening. The disturbance will also bring snow showers and squalls to the northern Vermont high country just as the Wednesday ski day is winding down. The event will be short-lived, but a few good bursts of snow should provide 1-4 inches of wind driven snow to the high country around the MRV and possibly a bit more from Stowe northward to the Canadian border. The week is expected to finish on the dry but cold side with temperatures below zero Thursday and Friday morning in many places while afternoon readings are only in the single numbers Thursday and 15 on Friday.
Though Friday is expected to be pretty sunny across the region as a whole, the weekend will feature more clouds but with moderating temperatures. There are hints that the push of more milder air could be the catalyst for a period of light snow Saturday but that remains to be seen. On Sunday we could see temperatures get pretty close to the freezing mark and likely exceed across some of the low lying areas.
The pattern for Christmas week now looks pretty well-defined. Though I wouldn't describe it as terrible, it certainly doesn't look particularly ideal. Much of the country's unsettled weather will be focused on California and the southern Rockies. The San Juan Mountains appear to be in line for a extra merry Christmas in 2019. The weather east of the Mississippi River appears quite mild. Interior New England will be one of the final hold outs this weekend we too can expect at least a day of milder temperatures on the mountain. Fortunately it only appears to be a 24-36 hour occurrence (Monday into Christmas eve) and one not accompanied by a significant amount of mixed precipitation or rain.
As the week progresses, there are continued signs that the ridge in the jet stream responsible for the milder weather will weaken and allow colder air to sink southward into interior New England. The question relates to what actual weather will accompany this push of colder weather on the 26th and 27th of the month. Some of the aforementioned storminess out west appears likely to push eastward toward the upper Midwest. Might some of this moisture end up falling as some late-week or weekend (December 28-29) snow in Vermont ? Quite possibly but the pattern does not support any notion of a big storm. Beyond that, there are continued signs of both storminess across the country and cold air focused on the western United States. In the preseason outlook, I highlighted the blob of ocean warmth in the eastern Pacific south of the Gulf of Alaska. For now it seems like a preferred location for a jet stream ridge which is not entirely ideal but again, we've seen worse patterns, especially around the holidays.
Though Friday is expected to be pretty sunny across the region as a whole, the weekend will feature more clouds but with moderating temperatures. There are hints that the push of more milder air could be the catalyst for a period of light snow Saturday but that remains to be seen. On Sunday we could see temperatures get pretty close to the freezing mark and likely exceed across some of the low lying areas.
The pattern for Christmas week now looks pretty well-defined. Though I wouldn't describe it as terrible, it certainly doesn't look particularly ideal. Much of the country's unsettled weather will be focused on California and the southern Rockies. The San Juan Mountains appear to be in line for a extra merry Christmas in 2019. The weather east of the Mississippi River appears quite mild. Interior New England will be one of the final hold outs this weekend we too can expect at least a day of milder temperatures on the mountain. Fortunately it only appears to be a 24-36 hour occurrence (Monday into Christmas eve) and one not accompanied by a significant amount of mixed precipitation or rain.
As the week progresses, there are continued signs that the ridge in the jet stream responsible for the milder weather will weaken and allow colder air to sink southward into interior New England. The question relates to what actual weather will accompany this push of colder weather on the 26th and 27th of the month. Some of the aforementioned storminess out west appears likely to push eastward toward the upper Midwest. Might some of this moisture end up falling as some late-week or weekend (December 28-29) snow in Vermont ? Quite possibly but the pattern does not support any notion of a big storm. Beyond that, there are continued signs of both storminess across the country and cold air focused on the western United States. In the preseason outlook, I highlighted the blob of ocean warmth in the eastern Pacific south of the Gulf of Alaska. For now it seems like a preferred location for a jet stream ridge which is not entirely ideal but again, we've seen worse patterns, especially around the holidays.
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