Lots of exciting times are on the horizon but I am bitter about the upcoming weekend. This time we had nearly a 2-week stretch of extreme cold including several days of -20, we have ice on a third of Lake Ontario and nearly all of Lake Huron (first time for that in 20 years) and yet our first big precipitation event in the "activated" pattern will be a snow to ice event. According to the Euro, precipitation has the chance of changing to freezing rain and even rain for a short time. The weekend system is not especially strong. It will travel up through the eastern Great Lakes and without any hesitation, head into the St Lawrence Valley, bringing its push of warmth into interior New England. We should see some snow late in the day Saturday as temperatures moderate to the freezing mark, but the snow will taper off and precipitation will continue as drizzle or freezing drizzle. By Sunday morning, temperatures could be a few degrees above freezing and we could see a few rain showers early in the day if the Euro model turns out to be correct and I am afraid it might be. I know a lot of forecasts out there including the NWS are more or less suggesting primarily a snow event and I am still hopeful but not encouraged by some of the latest indications.
So with that negativity out of my system lets talk about next week. In the last update I mistakenly thought Wednesday was the 4th and thus advertised that storm for the "4th". It is however the 5th, not the 4th and it is this storm and this day we are getting increasingly excited about. Models have been fairly consistent with the exception of perhaps one cycle and have generally been showing a healthy and very moist system moving out of Texas into the Ohio Valley and ultimately right at interior New England. Unlike the weekend event, the storm will transfer much of its energy to the coast and unlike the weekend event, we will have a fresh supply of cold air to work with both in front of this system and behind it. Nonetheless, we still have to hope the storm cuts a bit further south verses some current indications. I don't think the current track is suggesting any ice or rain but we could see a heavy snow to sleet event and could also be impacted by a dry slot if the area of low pressure tracks too close to the region. Optimistically speaking, if the storm tracks close to where the ensembles have it, the snow totals could be impressive and we will be back in business across all of northern and central Vermont.
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Thursday, January 30, 2014
Wednesday, January 29, 2014
Active pattern approaching and the storm watch is beginning to gaze at February 4
We are getting close to February which means it's "crunch time" as far as the ski season goes. It certainly will be "crunch time" in this ski season since we are approaching a much more active period of weather. The region will have some tepid support from a loosely negative AO but the long wave pattern will refocus much of the cold on the western or central third of the country. In short, this means that storms which form as a result of the often mentioned split flow scenario will take aim at interior New England and should bring lots of precipitation our way.
Given how this year has progressed and given some of the model data, there is going to be some understandable consternation. Each of the next several winter weather events will involve a mild push of air which will try and dislodge some well entrenched arctic cold. This type of battle can be a fruitful one so long as we avoid the ice or rain which sometimes briefly accompanies these storms.
The above paragraph was the disclaimer. The weather itself should consist of continued relative cold and mostly dry weather through Thursday. A decaying boundary should then spread light snow or flurries into the Green Mountains Friday which could result in a light accumulation. The snow should be accompanied by a big temperature moderation as readings could inch close to 30 during the afternoon hours. Most of the daytime hours Saturday will be dry with seasonable temperatures and light winds, but this new and much discussed pattern will begin to manifest itself during the weekend. The first results will come in the form of a garden variety storm system which will travel from the southern plains right into northern New England Sunday. With this storm will come a push of milder temperatures that will make an attempt to penetrate the region. A period of primarily snow should be the primary consequence Saturday night with a 2-6 inch accumulation by Sunday morning. If the storm were to track farther north, a period of sleet or freezing rain could occur prior to daybreak Sunday after the snow. Most of Sunday should feature temperatures near the freezing mark with flurries .
The storm that should consume most of our attention is a weather system that might impact the region around the time of Wednesday February 4th. This storm will move out of the southern Rockies early next week and will have a considerable amount of time to gather lots of moisture from the Gulf of Mexico before it tracks northeast, again, toward New England. This storm could bring a massive amount of precipitation with it as it tracks northeast, and with the correct infusion of upper air support, could become one of the bigger winter weather systems to impact the region this year. The range of possibilities though remains pretty wide a week out however. The storm could hug the coast and deliver the region only a glancing blow with snow as some recent runs of the American model have suggested. The aforementioned pattern supports a more inland track and one that could deliver interior New England either a big snow storm or a snow to ice event. It will be typical New England weather drama but we should have a decent chunk of cold to work with, both in front of, and in back of this storm so I am hopeful for a very positive result.
Another in a series of these weather systems could then impact the region around the weekend of the 8th and 9th. This happens after another stretch of cold weather at the end of the first full week of February. We said goodbye to an absolute folk music legend yesterday in Pete Seeger. What a full life he lived and I was lucky to be included in a very small slice of it. My mother helped to organize a benefit concert at my future high school and he was gracious enough to dine with us in our home after the show. I was 10 at the time and completely oblivious to the fact that we had hosted a living legend. Thanks for all your poetry and music PS, it was and will be an inspiration.
Given how this year has progressed and given some of the model data, there is going to be some understandable consternation. Each of the next several winter weather events will involve a mild push of air which will try and dislodge some well entrenched arctic cold. This type of battle can be a fruitful one so long as we avoid the ice or rain which sometimes briefly accompanies these storms.
The above paragraph was the disclaimer. The weather itself should consist of continued relative cold and mostly dry weather through Thursday. A decaying boundary should then spread light snow or flurries into the Green Mountains Friday which could result in a light accumulation. The snow should be accompanied by a big temperature moderation as readings could inch close to 30 during the afternoon hours. Most of the daytime hours Saturday will be dry with seasonable temperatures and light winds, but this new and much discussed pattern will begin to manifest itself during the weekend. The first results will come in the form of a garden variety storm system which will travel from the southern plains right into northern New England Sunday. With this storm will come a push of milder temperatures that will make an attempt to penetrate the region. A period of primarily snow should be the primary consequence Saturday night with a 2-6 inch accumulation by Sunday morning. If the storm were to track farther north, a period of sleet or freezing rain could occur prior to daybreak Sunday after the snow. Most of Sunday should feature temperatures near the freezing mark with flurries .
The storm that should consume most of our attention is a weather system that might impact the region around the time of Wednesday February 4th. This storm will move out of the southern Rockies early next week and will have a considerable amount of time to gather lots of moisture from the Gulf of Mexico before it tracks northeast, again, toward New England. This storm could bring a massive amount of precipitation with it as it tracks northeast, and with the correct infusion of upper air support, could become one of the bigger winter weather systems to impact the region this year. The range of possibilities though remains pretty wide a week out however. The storm could hug the coast and deliver the region only a glancing blow with snow as some recent runs of the American model have suggested. The aforementioned pattern supports a more inland track and one that could deliver interior New England either a big snow storm or a snow to ice event. It will be typical New England weather drama but we should have a decent chunk of cold to work with, both in front of, and in back of this storm so I am hopeful for a very positive result.
Another in a series of these weather systems could then impact the region around the weekend of the 8th and 9th. This happens after another stretch of cold weather at the end of the first full week of February. We said goodbye to an absolute folk music legend yesterday in Pete Seeger. What a full life he lived and I was lucky to be included in a very small slice of it. My mother helped to organize a benefit concert at my future high school and he was gracious enough to dine with us in our home after the show. I was 10 at the time and completely oblivious to the fact that we had hosted a living legend. Thanks for all your poetry and music PS, it was and will be an inspiration.
Sunday, January 26, 2014
Opportunities for big snow increase as we move into February but the core of arctic cold shifts west
The Vermont I know and love seems to be getting back to its normal wintry self. A couple of these little clipper systems have over performed and the mountain is quite literally "inching" closer to a optimal February. That all being said, we have some hurdles to jump over in early February as the core of the arctic cold shifts toward the west. There are some competing forces at play, which can prove to be a very good thing many times, but can be nerve racking as the margin between snow and ice and rain can often be razor thin.
In the shorter term, the mountain will get the benefits of a second clipper system. Some snow Sunday night and an additional period of snow Monday should amount to an additional 2-5 inches. Monday will feature temperatures in the 20's but another arctic onslaught is poised to send temperatures plummeting across the eastern half of the United States. In a relative sense, New England will get spared the worst extremes of this airmass (the Midwest will get that) but readings will fall below zero again on Monday, Tuesday and Wednesday nights and struggle to reach 10 both Tuesday and Wednesday. Temperatures on Thursday and Friday should moderate somewhat. The only snow during the middle part of the week will probably come Tuesday from instability or terrain induced snow showers and flurries.
We just continue to watch and wait for hints of a big storm. As I have pointed out this becomes more likely as we move toward February. The giant upper ridge in western North America responsible for the hugely positive PNA will subside, retrograding both north toward the pole and west into the northern Pacific. There will be energy in the Pacific undercutting this ridge, thus the split flow and thus the opportunity, we hope, for some big things. Because of this pattern evolution, the core of the arctic cold will shift decisively west and this type of long wave pattern puts New England in a battleground as arctic cold will have to fight off milder temperatures for control of the region.
As of Sunday morning, there is some stronger evidence of at least a semi organized weather system around Super Bowl Sunday or shortly thereafter. A storm that will gather strength in the southern plains and head northeast toward New England. In the last 24-48 hours, various models have shown a plethora of results ranging from a big snow event to a snow/ice event. It certainly has the makings of what could be a very good situation for interior New England as a whole but any push of mild air makes us nervous. Beyond the 2nd and 3rd, I expect at least two additional systems to impact the region and with the arctic oscillation settling comfortably into a favorable negative index I think the results should at least be somewhat positive. Still the pattern is not completely aligned with the center of cold favored over the central or western part of North America.
In the shorter term, the mountain will get the benefits of a second clipper system. Some snow Sunday night and an additional period of snow Monday should amount to an additional 2-5 inches. Monday will feature temperatures in the 20's but another arctic onslaught is poised to send temperatures plummeting across the eastern half of the United States. In a relative sense, New England will get spared the worst extremes of this airmass (the Midwest will get that) but readings will fall below zero again on Monday, Tuesday and Wednesday nights and struggle to reach 10 both Tuesday and Wednesday. Temperatures on Thursday and Friday should moderate somewhat. The only snow during the middle part of the week will probably come Tuesday from instability or terrain induced snow showers and flurries.
We just continue to watch and wait for hints of a big storm. As I have pointed out this becomes more likely as we move toward February. The giant upper ridge in western North America responsible for the hugely positive PNA will subside, retrograding both north toward the pole and west into the northern Pacific. There will be energy in the Pacific undercutting this ridge, thus the split flow and thus the opportunity, we hope, for some big things. Because of this pattern evolution, the core of the arctic cold will shift decisively west and this type of long wave pattern puts New England in a battleground as arctic cold will have to fight off milder temperatures for control of the region.
As of Sunday morning, there is some stronger evidence of at least a semi organized weather system around Super Bowl Sunday or shortly thereafter. A storm that will gather strength in the southern plains and head northeast toward New England. In the last 24-48 hours, various models have shown a plethora of results ranging from a big snow event to a snow/ice event. It certainly has the makings of what could be a very good situation for interior New England as a whole but any push of mild air makes us nervous. Beyond the 2nd and 3rd, I expect at least two additional systems to impact the region and with the arctic oscillation settling comfortably into a favorable negative index I think the results should at least be somewhat positive. Still the pattern is not completely aligned with the center of cold favored over the central or western part of North America.
Thursday, January 23, 2014
Clipper City Ale - The beer of choice
The old microbrew from Baltimore, MD, was sadly retired. When I looked up the web page, knowing I would reference it in the blog, it no longer existed. It remains however, the beer that comes to mind when we are expecting snow from multiple clippers. I sense some grumpiness regarding the weather pattern which is understandable. The mountain has endured a 4-day period of generally sub-zero temperatures and although we did get some snow on MLK day, we need a lot more to really make it happen for us.
I can't promise a big storm over the next 4 days but we should do nicely from our Clipper City Ale scenario. The first, a dynamic, coma-shaped surface feature, will rotate around our "hashtagged" polar vortex and spread snow to the Green Mountain range Saturday morning. The snow won't be particularly intense at any point during the day but should continue through the evening. The snow will be of a fluffy variety as it often is in clippers, and 3-5 inches of this low density stuff is what I would expect by late at night Saturday. Temperatures will moderate into the lower 20's Saturday with the snow but will fall sharply back into the single digits Sunday, the drier of the two days. The next clipper marks the entrance of a massive intrusion of arctic chill. Snow from this will arrive Sunday night and persist through early Monday. Once again, this system is capable of bringing another few inches (lets call it 2-4). It then turns brutally cold Monday evening into the overnight as the PV drops into the northern Great Lakes and then swings through southern Quebec Tuesday.
Unfortunately, and two days since this last update, there is no evidence of a late next week storm on any of the medium range operational models and I would not expect any talk of one. Not to say it can't happen but there is no evidence that any serious energy in the southern branch of the jet stream until the beginning of February. This isn't to say that it can't happen but that it simply doesn't look good as of now. The overall evolution of this pattern appears relatively in line with what was discussed previously. The extreme cold that was caused by the super-positive PDO regime will give way to a more variable but relatively normal temperature range. The combination however of some lingering cold and a more active jet stream should make for some exciting stuff I am hoping as we head into the month of February.
I can't promise a big storm over the next 4 days but we should do nicely from our Clipper City Ale scenario. The first, a dynamic, coma-shaped surface feature, will rotate around our "hashtagged" polar vortex and spread snow to the Green Mountain range Saturday morning. The snow won't be particularly intense at any point during the day but should continue through the evening. The snow will be of a fluffy variety as it often is in clippers, and 3-5 inches of this low density stuff is what I would expect by late at night Saturday. Temperatures will moderate into the lower 20's Saturday with the snow but will fall sharply back into the single digits Sunday, the drier of the two days. The next clipper marks the entrance of a massive intrusion of arctic chill. Snow from this will arrive Sunday night and persist through early Monday. Once again, this system is capable of bringing another few inches (lets call it 2-4). It then turns brutally cold Monday evening into the overnight as the PV drops into the northern Great Lakes and then swings through southern Quebec Tuesday.
Unfortunately, and two days since this last update, there is no evidence of a late next week storm on any of the medium range operational models and I would not expect any talk of one. Not to say it can't happen but there is no evidence that any serious energy in the southern branch of the jet stream until the beginning of February. This isn't to say that it can't happen but that it simply doesn't look good as of now. The overall evolution of this pattern appears relatively in line with what was discussed previously. The extreme cold that was caused by the super-positive PDO regime will give way to a more variable but relatively normal temperature range. The combination however of some lingering cold and a more active jet stream should make for some exciting stuff I am hoping as we head into the month of February.
Tuesday, January 21, 2014
It's all about the "Polar Vortex"
Very cold weather has enveloped the state and particularly the high country where temperatures even during the day have remained below zero Tuesday. This general theme should continue through the duration of the week and aside for a few insignificant flurries, it will remain dry. We had hoped a clipper Thursday could provide a little refreshening but the Polar Jet obliterates this thing before any constructive interaction can occur with the Atlantic Ocean. On Friday we should see temperatures inch above the zero line and with light winds and good visibility, it should almost feel nice.
Our next very good chance of snow comes Saturday from another clipper. These types of systems often lack substantial amounts of moisture but this one is a bit more dynamic and will mark the advance of a reenforcing shot of chill for Sunday. Light snow should begin pretty early in the day and continue through the evening. I don't expect we see a major accumulation from this but 2-4 inches is a good preliminary guess. Saturday's temps should also moderate, reaching the low 20's as the snow is flying. Flurries will continue through a good part of Sunday as well but we are back in the deep freeze with daytime temperatures between zero and 10.
The media has fallen in love with the "polar vortex" phrase and why not. It's an easy hashtag on twitter and a charismatic headline for cable news. This particular "vortex" of cold in the jet stream will position itself south of the Hudson Bay and impulses rotating around this feature will continuously bring big shots of extreme cold to New England over the next week. The last of these impulses and potentially the biggest shot of cold arrives early next week. I think we can be pretty sure that temperatures will nosedive toward the -20 degree range Tuesday or maybe Wednesday morning. The question relates to yet another clipper associated with this last PV impulse and whether or not it can deliver some additional snows to the region Monday. At this point it seems reasonable to expect at least a little.
Beyond the middle part of the week, it still appears as if the jet stream will split across western North America. A significant and potentially fruitful development. We should see a big increase in storminess across the country and there are now indications of that on various models late next week into early February. At the same time, we should see temperatures moderate; in fact, readings could actually creep above average by early February. In the end, there should be enough competing forces in the overall pattern to make this a potentially very good period for Vermont. The split flow across the west and just enough cold air positioned across Canada could be the ticket to some big snows. The first of these may or may not occur between January 30 and Feb 1 with additional chances thereafter.
Our next very good chance of snow comes Saturday from another clipper. These types of systems often lack substantial amounts of moisture but this one is a bit more dynamic and will mark the advance of a reenforcing shot of chill for Sunday. Light snow should begin pretty early in the day and continue through the evening. I don't expect we see a major accumulation from this but 2-4 inches is a good preliminary guess. Saturday's temps should also moderate, reaching the low 20's as the snow is flying. Flurries will continue through a good part of Sunday as well but we are back in the deep freeze with daytime temperatures between zero and 10.
The media has fallen in love with the "polar vortex" phrase and why not. It's an easy hashtag on twitter and a charismatic headline for cable news. This particular "vortex" of cold in the jet stream will position itself south of the Hudson Bay and impulses rotating around this feature will continuously bring big shots of extreme cold to New England over the next week. The last of these impulses and potentially the biggest shot of cold arrives early next week. I think we can be pretty sure that temperatures will nosedive toward the -20 degree range Tuesday or maybe Wednesday morning. The question relates to yet another clipper associated with this last PV impulse and whether or not it can deliver some additional snows to the region Monday. At this point it seems reasonable to expect at least a little.
Beyond the middle part of the week, it still appears as if the jet stream will split across western North America. A significant and potentially fruitful development. We should see a big increase in storminess across the country and there are now indications of that on various models late next week into early February. At the same time, we should see temperatures moderate; in fact, readings could actually creep above average by early February. In the end, there should be enough competing forces in the overall pattern to make this a potentially very good period for Vermont. The split flow across the west and just enough cold air positioned across Canada could be the ticket to some big snows. The first of these may or may not occur between January 30 and Feb 1 with additional chances thereafter.
Sunday, January 19, 2014
Looking hard for the snow in what will be a very chilly week
Winter is back at MRG with snowflakes flying and temperatures dropping. And with arctic cold in firm control of the weather in VT for at least the next 10 days or so, the question revolves around potential snow as in "when" and "how much". We got some from our Sunday/MLK day clipper but the mountain needs significantly more to get us toward 100 percent open.
Light snow on MLK should persist through much of the day amounting to another inch or two but temperatures will plummet through the teens as the next round of arctic cold descends on New England. Tuesday and Wednesday will be mostly dry with temperatures near -10 in the mornings and only near zero during the afternoons. Another clipper system will divide one shot of polar air from the next. This system has the capability of blowing up on the New England coast and delivering some snow to the region but it will probably be the wrong part of the region. As mentioned in the last update, the polar jet operates at a higher speed and can take systems out into the Atlantic very quickly. That being said, this is still a few days away and if this system can dig a little bit more, it could take a turn northward and bring us a bit of the good stuff. It will remain very cold through Friday with temperatures remaining well below zero at night and struggling to climb above zero during the day.
It should get more interesting this upcoming weekend and chances for snow should continue throughout the last full week of January. The weekend snow will be the result of another clipper and although this limits some upside potential with the storm, we will take the snow anyway we can get it and I expect another few inches here. The polar jet will take a final swing at the region early next week, potentially bringing the coldest weather of the season. This will be the the last hurrah so to speak of this positive PNA cycle and the western North America ridge will lose some of its intensity. As this is happening however, there is evidence of some serious splitting in the flow in the Pacific. This will open the door for some significant weather systems to impact much of the country during this last full week of the month and into early February. I think the first big chance for snow comes some time between the 29th and 31st of the month.
The cold weather should also subside somewhat by early February and although there are some indications that we swing back to a milder regime again, I think the pattern should stay much more interesting. Ensembles, at least two of them anyway, are showing that the once western North American ridge will migrate west and north and will keep the AO on the negative side and this should help prevent any thaws and hopefully keep us on the snowy side of passing low pressure centers.
Light snow on MLK should persist through much of the day amounting to another inch or two but temperatures will plummet through the teens as the next round of arctic cold descends on New England. Tuesday and Wednesday will be mostly dry with temperatures near -10 in the mornings and only near zero during the afternoons. Another clipper system will divide one shot of polar air from the next. This system has the capability of blowing up on the New England coast and delivering some snow to the region but it will probably be the wrong part of the region. As mentioned in the last update, the polar jet operates at a higher speed and can take systems out into the Atlantic very quickly. That being said, this is still a few days away and if this system can dig a little bit more, it could take a turn northward and bring us a bit of the good stuff. It will remain very cold through Friday with temperatures remaining well below zero at night and struggling to climb above zero during the day.
It should get more interesting this upcoming weekend and chances for snow should continue throughout the last full week of January. The weekend snow will be the result of another clipper and although this limits some upside potential with the storm, we will take the snow anyway we can get it and I expect another few inches here. The polar jet will take a final swing at the region early next week, potentially bringing the coldest weather of the season. This will be the the last hurrah so to speak of this positive PNA cycle and the western North America ridge will lose some of its intensity. As this is happening however, there is evidence of some serious splitting in the flow in the Pacific. This will open the door for some significant weather systems to impact much of the country during this last full week of the month and into early February. I think the first big chance for snow comes some time between the 29th and 31st of the month.
The cold weather should also subside somewhat by early February and although there are some indications that we swing back to a milder regime again, I think the pattern should stay much more interesting. Ensembles, at least two of them anyway, are showing that the once western North American ridge will migrate west and north and will keep the AO on the negative side and this should help prevent any thaws and hopefully keep us on the snowy side of passing low pressure centers.
Thursday, January 16, 2014
Winter is poised to make a frontal assault on the U.S.
Once every so often, the United States has one of those memorable winters. One of those winters where a weather pattern locks bitterly cold arctic air over much of the country for an extended period of the December to February period. Winters like 1918 (famous for the deadly flu), 1936, any of the winters in the late 70's, 1982 or 1994 are all remembered for long and very extreme outbreak's of bitterly cold air. Vermonters are probably not ready to award this distinction to the 2014 winter as of yet since much of the brunt of the cold and anomalous snow has been focused on the center of the country. But for another upcoming 10 day stretch, the central and eastern parts of the country will again be the focal point for another extended period of extreme cold. This will occur thanks the development of a very powerful blocking ridge in the jet stream extending from the western United States northward to the Yukon. This is one of the more impressive blocking features we have seen in this region going back at least a decade ,and it occurs in a year when the pooling efficiency of air masses in the polar regions has been particularly impressive. By the end of the month, January 2014 and perhaps the entire winter will be remembered as one of the coldest in a generation. Strong language, but well earned given the temperatures we are likely going to have to endure.
The presence of the polar jet over New England and the rest of the country is reeking havoc on the performance of the models. We have gotten some good indications regarding the general pattern evolution but the details have proven almost impossible to pin down. Storms will show up on a model run for the weekend and then disappear a day later. Another model might snow a big snow event for early next week and that storm will later vanish on a subsequent model run. To put it as plainly as possible, the polar jet operates in a different gear. Impulses rotate through the jet so quickly and the models have a hard time digesting what impact, if any, they will have on actual weather. In other words, we have and will continue to be teased now and again and a storm might sneak up on us very late in a forecast period.
For now, it seems like there is some consensus on the weekend. Temperatures will stay in a very tolerable range, climbing to near 30 both Saturday and Sunday and only falling into the teens. Enjoy it because beyond that lies an abyss of brutally cold weather for New England. We will also get some snow this weekend. Two clipper systems are responsible for this. The first was the one we had hoped would ultimately bomb-out along the coast delivering lots of snow; instead, we should see a period of light snow Saturday evening into the overnight amounting hopefully to a few inches. On Sunday a clipper will rapidly advance southeast out of Ontario on the wings of the arriving polar jet. This system will deliver another few inches of snow Sunday night. Flurries will continue into Monday but the story for the rest of the week will be cold, brutal cold. Temperatures for much of the week will be below zero on the mountain including readings lower than 10 below in the morning and day time temperatures that struggle to get above zero. We have been teased and may continue to be teased with a potential storm around the time of Friday/Saturday the 24th/25th. I think this system has the potential to be more than just a tease but time will tell.
The ultra positive PNA will continue to support the bitterly cold temperatures until at least the 28th of January and then it gets interesting. The strength of the ridge in the Yukon will relax and there are signs of some serious splitting in the jet stream in the Pacific. This is the kind of situation that can lead to big time snow events for both New England and many other places.
The presence of the polar jet over New England and the rest of the country is reeking havoc on the performance of the models. We have gotten some good indications regarding the general pattern evolution but the details have proven almost impossible to pin down. Storms will show up on a model run for the weekend and then disappear a day later. Another model might snow a big snow event for early next week and that storm will later vanish on a subsequent model run. To put it as plainly as possible, the polar jet operates in a different gear. Impulses rotate through the jet so quickly and the models have a hard time digesting what impact, if any, they will have on actual weather. In other words, we have and will continue to be teased now and again and a storm might sneak up on us very late in a forecast period.
For now, it seems like there is some consensus on the weekend. Temperatures will stay in a very tolerable range, climbing to near 30 both Saturday and Sunday and only falling into the teens. Enjoy it because beyond that lies an abyss of brutally cold weather for New England. We will also get some snow this weekend. Two clipper systems are responsible for this. The first was the one we had hoped would ultimately bomb-out along the coast delivering lots of snow; instead, we should see a period of light snow Saturday evening into the overnight amounting hopefully to a few inches. On Sunday a clipper will rapidly advance southeast out of Ontario on the wings of the arriving polar jet. This system will deliver another few inches of snow Sunday night. Flurries will continue into Monday but the story for the rest of the week will be cold, brutal cold. Temperatures for much of the week will be below zero on the mountain including readings lower than 10 below in the morning and day time temperatures that struggle to get above zero. We have been teased and may continue to be teased with a potential storm around the time of Friday/Saturday the 24th/25th. I think this system has the potential to be more than just a tease but time will tell.
The ultra positive PNA will continue to support the bitterly cold temperatures until at least the 28th of January and then it gets interesting. The strength of the ridge in the Yukon will relax and there are signs of some serious splitting in the jet stream in the Pacific. This is the kind of situation that can lead to big time snow events for both New England and many other places.
Wednesday, January 15, 2014
Even if we miss a big weekend snow, good times lay ahead !!
We had collectively hoped that our midweek update would be dominated by storm talk, especially after enduring a devastating January thaw that has shut off operations at MRG. We can still talk and we can still hope, but candidly speaking, the models are suggesting that our weekend storm remains a pipe dream. We have finally nudged temperatures back below the freezing mark and a little closer to seasonable levels. The pattern, as defined by the jet stream, will gradually become more amplified by late in the week and into the early part of the weekend. Conditions will be ripe for a storm and the the right upper level impulse at the right time is certainly capable of lighting the proverbial match. On Friday, the weather map will consist of an eastward moving clipper system. The energy from this system will be competing for territory with a conglomeration of weaker low pressure centers off the Atlantic coast. The competition is not a healthy one as far as we are concerned. The weather systems over the Atlantic will try and suck the clipper off the coast Saturday and eliminate the chance for a big snow. If the timing and positioning of these many weather systems within this amplified set -up turn out to be different than currently advertised, it could significantly alter how things play out this weekend.
In terms of actual weather on the mountain, the decaying clipper should be bring a pool of instability to the Green Mountains that is capable of igniting show showers. I would not entirely rule out something bigger but the evidence simply isn't there as of Wednesday morning. As one clipper gets sucked out to sea, another clipper, this one straight out of western Ontario, races southeast Sunday. This system will not be in competition with any Atlantic storm and should spread some light snow into Vermont during the day. Within a few days, I think we will have a better idea of how much snow can fall both days this weekend. Temperatures on both days this weekend will be in the 20's during the days and teens or single numbers at night (very average).
The expectations in the longer range are the same as a few days ago. The amplification of the jet stream this weekend begins the metamorphosis of what will become a classic and beautiful looking positive PNA pattern. Specifically, this refers to the development of a large upper level ridge in western North America that will ultimately extend deep into the Yukon. A feature such as this in the jet stream is capable of sending very cold weather into New England and many other places. It should eliminate the chances of any additional thaws, greatly reduce the chances of any rain and increase the chances for a big snow. Various models hint at several chances for snow within the two week stretch beginning this weekend and persisting through the end of the month. The first comes around the time frame of Tuesday Jan 21. Snow from a clipper system are possible later in the week followed by what could be another round of bitterly cold temperatures. In the last week of the month, there are signs of some splitting in the jet stream which would really leave the door open for several big snows.
Sunday, January 12, 2014
Miserable stretch of weather will give way to a pattern conducive for both snow and cold
Almost done with this 4-day horror movie of rain and warmth. Monday and Tuesday will be the last of it for a while we think. Both of these days should feature near 40-degree temperatures with Monday the dry day and Tuesday featuring the rain. Models have struggled to reach an agreement regarding this system over the past week and it looks at this point like it will be a rather disorganized storm. There is a coastal element to this system which will prevent excessively mild air from reaching Vermont; in fact, precipitation could be snow for a time at the highest summits, including General Stark. Whatever falls Tuesday, rain or snow, it won't be a lot and it will end a very forgettable stretch of weather.
Beyond Tuesday there are all kinds of interesting details to sort through and lots of these details will appear different from day to day. Most importantly is that the pattern will align very favorably for at least a two week stretch beginning the 15th and persisting through most of the rest of January. There will be several chances for snow, many of these will be light accumulations but I think at least 2 should be significant. Frustrations have been running a little high in the powder hound community but I expect these frustrations to be alleviated to a degree. It is, as mentioned a few times, a beautiful looking positive PNA structure in the jet stream. Ensembles actually seem rather confident, that the amplifications from this pattern will peak at two different times, once this upcoming weekend (the 19th and another toward the following weekend (the 23rd - 27th).
The specifics in this two week period are a clouded, foggy mess at this point. An important point to remember however is how imperative it is to get the pattern aligned correctly and the rest will follow. The first chance for snow does come Wednesday from a clipper system following closely on the heals of Tuesday's wet system. This looks to be a storm capable of delivering 2-4 inches to the mountain but it will be of the wet variety before temperatures finally tumble back to seasonable levels Wednesday night. The more interesting scenario involves the weather map for the upcoming weekend. The pattern as mentioned will become highly amplified. It will be a "tinderbox" so to speak. Two clippers will move southeast into this amplification, one Friday and one Saturday. Either one of these systems could explode along the New England coast and become a big storm for somebody. Both systems could also simply remain clipper systems, failing to yield the significant accumulation that is so desperately needed. At the very least, I think the upcoming weekend will feature some snow. Furthermore, it will a chilly time with temperatures in the teens by day and 0-10 at night.
The chilly temperatures along with the chance for at least terrain induced snow should continue through Monday the 20th. The pattern will temporarily relax during the middle of the week but as mentioned, we should see another major jet amplification toward the end of the week and into the weekend. This will open the door and give the region another opportunity for a big storm somewhere between the 23rd and 27th of the month.
Friday, January 10, 2014
Yes, in spite of what will happen over the next 4-5 days, I like how the back two weeks of January look
Lots mild air and some rain is poised to head in our direction. Yes indeed, what a purging this is going to be over the next few days but with conditions remaining on the crusty and thin side, we might as well purge the system and start anew. I am not sure how many truly want the gory details of the mild weather and rain, if not just skip ahead to the next paragraph. After some freezing rain Saturday morning, the rain takes over during the day along with temperatures near or above 45 degrees. We should see some heavy rain from this system by Saturday evening and the result will be more significant damage to an already thin snowpack. Drier weather and snow flurries will return for Sunday but the airmass is Pacific in origin and temperatures should remain above the freezing mark in many low lying areas (sub freezing at the summits). Spring conditions will then re-emerge for Monday as another round of very mild weather pushes northward, essentially rubbing our noses in it again.
Alright then, I think I covered most of the bad news and most of this we already knew about anyway. One of the lingering questions in the last post was a potential second "warm" system, would it actually exist at all and how much rain would fall. Three days ago models failed to provide any consensus on this question and 72 hours later nothing has changed. That being said, there are some interesting developments that may or may not be good news. This potential second system, at the very least, appears to be a little slower in its arrival. This allows an extra day for the polar air to enter the equation by the middle of the week. An important disclaimer here however, Tuesday is still very mild and if precipitation arrives, it is very likely to begin as a rain and potentially a very warm one. As the polar jet sends its energy southeast Wednesday, it could infuse the storm with some much needed cold air as well as some energy. Lots of details need to be sorted out so its not worth getting into the nuts and bolts of all this too much except to say that some snow is back on the table as a possibility for Wednesday/Thursday. Some of this will be storm related some of this will be of the more terrain-induced variety. It could be a nice accumulation to get us jump started again or it could end up being next to nothing.
Now to the good news. As of late Friday, the ensembles which not entirely sorted through the next 5 days with any consistency, also fail to provide a conclusive indication on the back 2 weeks of January. That being said, I am a strong supporter of the picture painted by the Euro and Canadian ensembles. They both allow a nice looking positive PNA structure to emerge and the Euro in particular allows this connection to the poles. This should close the door on the Pacific air and open the door for east coast amplifications and a storm track that should, in general, favor New England for snow. Its important to note that the American ensemble package does not agree with this assessment but the American is conforming to one of its best known biases which involves progressing the pattern too aggressively. In this case I think, way too aggressively. In short, I think this will prove to be an excellent period for New England ski country although I can't say for sure when our best powder days will be and how long it will take to replenish the ravaged bases of central and northern Vermont. Models have done a very poor job of accurately assessing the southern branch of the jet stream and its influence on the weather map. Again, models are suggesting that much of the snow in past Wednesday January 15th comes either by the way of clipper systems or terrain induced powder (The first such system comes on or just before that weekend of the 17th-18th). Some southern branch involvement could certainly produce a big storm in this pattern and it may be that forecasters will have some trouble finding this storm outside of a 5 or 6 day window.
Alright then, I think I covered most of the bad news and most of this we already knew about anyway. One of the lingering questions in the last post was a potential second "warm" system, would it actually exist at all and how much rain would fall. Three days ago models failed to provide any consensus on this question and 72 hours later nothing has changed. That being said, there are some interesting developments that may or may not be good news. This potential second system, at the very least, appears to be a little slower in its arrival. This allows an extra day for the polar air to enter the equation by the middle of the week. An important disclaimer here however, Tuesday is still very mild and if precipitation arrives, it is very likely to begin as a rain and potentially a very warm one. As the polar jet sends its energy southeast Wednesday, it could infuse the storm with some much needed cold air as well as some energy. Lots of details need to be sorted out so its not worth getting into the nuts and bolts of all this too much except to say that some snow is back on the table as a possibility for Wednesday/Thursday. Some of this will be storm related some of this will be of the more terrain-induced variety. It could be a nice accumulation to get us jump started again or it could end up being next to nothing.
Now to the good news. As of late Friday, the ensembles which not entirely sorted through the next 5 days with any consistency, also fail to provide a conclusive indication on the back 2 weeks of January. That being said, I am a strong supporter of the picture painted by the Euro and Canadian ensembles. They both allow a nice looking positive PNA structure to emerge and the Euro in particular allows this connection to the poles. This should close the door on the Pacific air and open the door for east coast amplifications and a storm track that should, in general, favor New England for snow. Its important to note that the American ensemble package does not agree with this assessment but the American is conforming to one of its best known biases which involves progressing the pattern too aggressively. In this case I think, way too aggressively. In short, I think this will prove to be an excellent period for New England ski country although I can't say for sure when our best powder days will be and how long it will take to replenish the ravaged bases of central and northern Vermont. Models have done a very poor job of accurately assessing the southern branch of the jet stream and its influence on the weather map. Again, models are suggesting that much of the snow in past Wednesday January 15th comes either by the way of clipper systems or terrain induced powder (The first such system comes on or just before that weekend of the 17th-18th). Some southern branch involvement could certainly produce a big storm in this pattern and it may be that forecasters will have some trouble finding this storm outside of a 5 or 6 day window.
Tuesday, January 7, 2014
Weekend looking uglier but there is a light at the end of this tunnel
Cold weather and snow has made national headlines and in most places has been the topic of water cooler talk in most U.S. cities east of the Mississippi. Incredibly, much of interior New England, particularly Vermont, is starving for snow. It is not an optical illusion either, the Green Mountain chain, in a relative sense, has performed downright awful compared to almost everywhere else. Most Midwest locations have seen 200-400 percent of their normal snowfall to date while Boston, Cape Cod and most of the rest of the I95 corridor have also seen nearly double their normal snowfall (prorated to the date). Especially frustrating is the fact that the region has seen its coldest November 1st - January 7th period since 2000-2001 and the consistent snowfall has been glaringly absent.
The old saying "when it rains it pours" is especially applicable at low points during the ski season. The "evil empire" will be up to its old tricks. It will make a relatively brief appearance but even one appearance is one appearance too many as far as I am concerned. It will be all dressed up in its full regalia as well, flushing the arctic air out of Vermont and setting the stage for upwards of two rain events along with several mild days. Before all that nonsense begins, we still have a few more cold days to deal with and possibly some light snow or flurries Friday (although it does not appear that this will amount to much). By Saturday, Pacific air makes it's initial push and the system responsible for this "push" will have some moisture to work with. Precipitation should begin Saturday as some freezing rain or a cold rain before changing to all rain Saturday night.
By Sunday the pattern will have become entirely zonal and this could turn out to be the mildest day of the month at MRG with temperatures soaring well into the 40's. There has been some inconsistencies in the models handling of a potential second weather system late Sunday into Monday. It is pretty unlikely however that any precipitation would be snow no matter what happens. The American model allows the pattern to amplify a bit and suggests that a storm of some significance will move up the spine of the Appalachian Mountains and bring more significant rain to the region. There seems to be more consensus as of Tuesday night that this second system will be flatter, pass innocently to the north producing another very mild day Monday with rain showers.
After Monday the Pacific "evil empire" begins to flicker out and we should see a gradual return to colder weather. Ultimately, I think the weather will turn much colder by the 17th or 18th of the month as a nice looking positive PNA structure emerges in the jet stream configuration. If we are lucky, we could start seeing some new snow around the 15th of the month. Even pessimistically thinking, some new snow should be on the ground by the weekend of the 18th and 19th. Medium range models have occasionally placed a storm here or there in the week beginning on the 19th but those details will appear to be very fluid from day to day. Brace yourselves as we enter the tunnel, it's a dark one but at least I can already see the light at the end.
The old saying "when it rains it pours" is especially applicable at low points during the ski season. The "evil empire" will be up to its old tricks. It will make a relatively brief appearance but even one appearance is one appearance too many as far as I am concerned. It will be all dressed up in its full regalia as well, flushing the arctic air out of Vermont and setting the stage for upwards of two rain events along with several mild days. Before all that nonsense begins, we still have a few more cold days to deal with and possibly some light snow or flurries Friday (although it does not appear that this will amount to much). By Saturday, Pacific air makes it's initial push and the system responsible for this "push" will have some moisture to work with. Precipitation should begin Saturday as some freezing rain or a cold rain before changing to all rain Saturday night.
By Sunday the pattern will have become entirely zonal and this could turn out to be the mildest day of the month at MRG with temperatures soaring well into the 40's. There has been some inconsistencies in the models handling of a potential second weather system late Sunday into Monday. It is pretty unlikely however that any precipitation would be snow no matter what happens. The American model allows the pattern to amplify a bit and suggests that a storm of some significance will move up the spine of the Appalachian Mountains and bring more significant rain to the region. There seems to be more consensus as of Tuesday night that this second system will be flatter, pass innocently to the north producing another very mild day Monday with rain showers.
After Monday the Pacific "evil empire" begins to flicker out and we should see a gradual return to colder weather. Ultimately, I think the weather will turn much colder by the 17th or 18th of the month as a nice looking positive PNA structure emerges in the jet stream configuration. If we are lucky, we could start seeing some new snow around the 15th of the month. Even pessimistically thinking, some new snow should be on the ground by the weekend of the 18th and 19th. Medium range models have occasionally placed a storm here or there in the week beginning on the 19th but those details will appear to be very fluid from day to day. Brace yourselves as we enter the tunnel, it's a dark one but at least I can already see the light at the end.
Sunday, January 5, 2014
Evil empire will make getting some much needed new snow a challenge
I consider the 60 degree rise in temperatures, the ice and the rain to be a bit of a debauchery. Whenever you see temperatures of 20 to 25 below, you should earn some free powder simply from attrition. New England winter weather can be very unforgiving in that regard and as noteworthy as the weather has been for all its snow and cold across much of the country, MRG has done poorly in a relative sense and deserve some good fortune in the near future.
Cold weather will be back in command by Monday evening after the wet start to the day. This is the same, very powerful arctic intrusion that will send temperatures across the midwest to their lowest lowest levels in a decade. In Vermont by contrast, the cold weather will be less intense than this past Friday, mainly because the core of the airmass took the scenic south of the Great Lakes and had a chance to modify before reaching New England. Still we should see readings between -5 and 15 Tuesday and Wednesday. There is a layer of marginal instability that will provide the platform for some terrain induced and champlain induced snows Tuesday. I expect a few much needed inches from this, enough to get us back in the wintry spirit.
So our need for fresh powder is certainly high but we will be going up against the "evil empire" for a few days as advertised previously. Pacific air will begin scouring the cold out of mid latitude North America later this week. It will take one or two weather systems to rid the northeast of the arctic cold. These are weak systems but they could actually bring interior New England some snow ahead of what we expect will be 1 or 2 pretty mild days around the 12th or 13th of the month. The first of these systems might bring a little snow Thursday night and accumulations should be pretty light. The second on Saturday will have limited amount of remaining cold air to work with, but perhaps just enough to bring some snow to the mountain or at worst mixed precipitation. If the evil empire is going to bring rain or 40-degree temperatures as mentioned, it is likely to happen between Sunday and Tuesday (12th-14th). I am holding out hope that the potential thaw is mitigated or eliminated which could happen if the potential east coast ridge gets flattened somewhat. It will be difficult chore to avert this entirely.
The good news is that the consensus of ensemble data eliminates the evil empire by allowing the Pacific jet to loosen toward the middle of January. The ridge in the eastern Pacific is actually pushed east into western North America and this allows a positive PNA pattern to emerge. We should see a return to more serious arctic chill and hopefully 1 or 2 decent winter storms between the 15th and 25th of the month.
Cold weather will be back in command by Monday evening after the wet start to the day. This is the same, very powerful arctic intrusion that will send temperatures across the midwest to their lowest lowest levels in a decade. In Vermont by contrast, the cold weather will be less intense than this past Friday, mainly because the core of the airmass took the scenic south of the Great Lakes and had a chance to modify before reaching New England. Still we should see readings between -5 and 15 Tuesday and Wednesday. There is a layer of marginal instability that will provide the platform for some terrain induced and champlain induced snows Tuesday. I expect a few much needed inches from this, enough to get us back in the wintry spirit.
So our need for fresh powder is certainly high but we will be going up against the "evil empire" for a few days as advertised previously. Pacific air will begin scouring the cold out of mid latitude North America later this week. It will take one or two weather systems to rid the northeast of the arctic cold. These are weak systems but they could actually bring interior New England some snow ahead of what we expect will be 1 or 2 pretty mild days around the 12th or 13th of the month. The first of these systems might bring a little snow Thursday night and accumulations should be pretty light. The second on Saturday will have limited amount of remaining cold air to work with, but perhaps just enough to bring some snow to the mountain or at worst mixed precipitation. If the evil empire is going to bring rain or 40-degree temperatures as mentioned, it is likely to happen between Sunday and Tuesday (12th-14th). I am holding out hope that the potential thaw is mitigated or eliminated which could happen if the potential east coast ridge gets flattened somewhat. It will be difficult chore to avert this entirely.
The good news is that the consensus of ensemble data eliminates the evil empire by allowing the Pacific jet to loosen toward the middle of January. The ridge in the eastern Pacific is actually pushed east into western North America and this allows a positive PNA pattern to emerge. We should see a return to more serious arctic chill and hopefully 1 or 2 decent winter storms between the 15th and 25th of the month.
Thursday, January 2, 2014
New England winter weather at its finest
Winter is raging early this 2014. Sub-zero temperatures cover most of interior New England Friday morning and even Logan airport, on the water reported heavy snow for a few hours with a temperatures within a few degrees of 5. That is winter ! Mad River Glen enthusiasts have not been on the receiving end of all the goodness. We underperformed on 12/29, missing the heavy snow by 20 or so miles, did do particularly well on Champlain/terrain induced snow in spite of cold weather this past week, and the windblown snow Thursday and Thursday, although much needed, fell short of what we had hoped for a few days ago.
This has been a classic New England winter so far and will live up to that billing Saturday and Sunday. On Saturday morning, temperatures will be close to -20 F and by Sunday night we could be seeing plain rain and temperatures surging to 40. This type of weather is absolutely excruciating if your a Vermont powder hound, but I guarantee this is not the first time many of you have seen this happen and it won't be the last either. The Euro was on to this problem very early and some of the other models have finally caught up. The Jet Stream will send a polar vortex southward into the Great Lakes carving out the "bowling ball" configuration by the end of this weekend. This allows a widespread outbreak of very intense cold weather to move into the middle part of the U.S. but at the same time, warm air will surge north ahead of a storm poised to track north through the eastern Great Lakes. The very "unforgiving" shape of the jet stream will prevent this storm from making any sort of real contact with the Atlantic Ocean. This means that the storm will fail to make the all-important jump to the coast which thwarts many of the would-be warm surges. This warm push will be a brief one, but it will make it to Vermont and allow for a period rain Sunday night and Monday morning following some freezing rain Sunday afternoon. I would allow for the chance that a greater percentage of Sunday night's precipitation is freezing rain but none of this is particularly good news. Saturday will be on the dry side with good visibility. Temperatures after that cold start should rebound to near 20 with tolerable winds compared to that of Friday.
The cold air that follows the storm Sunday night is incredibly intense but since it took the scenic route south of the Great Lakes, the air mass will have modified a touch. Temperatures will nonetheless be in the single numbers for high temperatures Tuesday and Wednesday and below zero during the morning. We should see a period of snow on the back end of the storm Monday (1/6) and a shallow layer of instability through much of Tuesday should keep snow showers and even a few squalls in the area. This should freshen up the mountain somewhat by the middle of the week in spite of the very cold weather. The intensity of the cold should relax along with the snow shower activity by later Wednesday into Thursday. We could see some snows Friday into the weekend thanks to some warm advection.
I have hinted at a more ominous looking long range but didn't update this a few days ago. The "evil empire" is showing its face, especially in the European Ensemble package by around the 10th of the month. The "evil empire" has been prevalent each of the last two years and it basically consists of a large ridge in the jet stream across the eastern Pacific coupled with trough that covers the Bering Sea and Alaska. The two features act to tighten the jet stream in the Pacific thus scouring out the Arctic air in the U.S. and displacing it with mild Pacific air. It's important to note that the different ensemble packages are showing varying degrees of this. The American and Canadian ensembles both showed an east coast warm-up, peaking out around January 13th before giving way to colder weather by the 15th or so. The way this winter has behaved, I think this is totally reasonable. There is no reason to expect a prolonged shift to warmer weather but I would expect a significant 1-2 day push of warm temperatures before it ends.
This has been a classic New England winter so far and will live up to that billing Saturday and Sunday. On Saturday morning, temperatures will be close to -20 F and by Sunday night we could be seeing plain rain and temperatures surging to 40. This type of weather is absolutely excruciating if your a Vermont powder hound, but I guarantee this is not the first time many of you have seen this happen and it won't be the last either. The Euro was on to this problem very early and some of the other models have finally caught up. The Jet Stream will send a polar vortex southward into the Great Lakes carving out the "bowling ball" configuration by the end of this weekend. This allows a widespread outbreak of very intense cold weather to move into the middle part of the U.S. but at the same time, warm air will surge north ahead of a storm poised to track north through the eastern Great Lakes. The very "unforgiving" shape of the jet stream will prevent this storm from making any sort of real contact with the Atlantic Ocean. This means that the storm will fail to make the all-important jump to the coast which thwarts many of the would-be warm surges. This warm push will be a brief one, but it will make it to Vermont and allow for a period rain Sunday night and Monday morning following some freezing rain Sunday afternoon. I would allow for the chance that a greater percentage of Sunday night's precipitation is freezing rain but none of this is particularly good news. Saturday will be on the dry side with good visibility. Temperatures after that cold start should rebound to near 20 with tolerable winds compared to that of Friday.
The cold air that follows the storm Sunday night is incredibly intense but since it took the scenic route south of the Great Lakes, the air mass will have modified a touch. Temperatures will nonetheless be in the single numbers for high temperatures Tuesday and Wednesday and below zero during the morning. We should see a period of snow on the back end of the storm Monday (1/6) and a shallow layer of instability through much of Tuesday should keep snow showers and even a few squalls in the area. This should freshen up the mountain somewhat by the middle of the week in spite of the very cold weather. The intensity of the cold should relax along with the snow shower activity by later Wednesday into Thursday. We could see some snows Friday into the weekend thanks to some warm advection.
I have hinted at a more ominous looking long range but didn't update this a few days ago. The "evil empire" is showing its face, especially in the European Ensemble package by around the 10th of the month. The "evil empire" has been prevalent each of the last two years and it basically consists of a large ridge in the jet stream across the eastern Pacific coupled with trough that covers the Bering Sea and Alaska. The two features act to tighten the jet stream in the Pacific thus scouring out the Arctic air in the U.S. and displacing it with mild Pacific air. It's important to note that the different ensemble packages are showing varying degrees of this. The American and Canadian ensembles both showed an east coast warm-up, peaking out around January 13th before giving way to colder weather by the 15th or so. The way this winter has behaved, I think this is totally reasonable. There is no reason to expect a prolonged shift to warmer weather but I would expect a significant 1-2 day push of warm temperatures before it ends.