Wednesday, January 31, 2018

Lots of chances for significant snow over the next two weeks should put an end to this encrusted stretch of late January weather

We've reached the end of January and the "encrusted" snow conditions. We will begin to add snow somewhat slowly at first but there's so much potential in the upcoming pattern that it will be difficult to imagine anything but substantial improvements within a week. Some light snow Wednesday night and early Thursday will become somewhat gloppy in the valley areas and won't amount to much anyway. The high country can squeeze out about an inch or two before temperatures take a run at the freezing mark during the afternoon. Additional snow arrives along with an arctic boundary Thursday evening and night. We should see some enhancement from Lake Champlain which will help the high country score an additional 1-3 inches prior to Friday morning. I was hoping to promise a bit more but the sub-tropical connection looks weaker today and the weather system appears disorganized and will be overwhelmed by the incoming arctic cold.

The upcoming burst of arctic chill will send temperatures plummeting to near 10 degrees Friday and then below zero Friday night. Aside from morning snow showers and flurries, later Friday, Friday night and  Saturday will be rather dry. We finally get to add a little more intrigue into the outlook Saturday night into Sunday. The remnants of a rather energetic Pacific Northwest pattern will advance eastward with limited amounts of moisture. As it arrives with its light snow Saturday night, more moisture is expected to gather along the Gulf Coast and allow a separate weather system to take shape in the eastern Caralinas on Sunday. Now we have been teased with southern branch moisture on a few occasions the last several weeks and with a now weakened La Nina, such events are a bit more likely. So far however, they've generally been a fail, but it would sure be nice if this one were not. This storm is expected to strengthen some and move up the coast into some weakening cold air. It looks primarily like a rain/sleet event along the coast but Vermont is positioned to score decent snow if the moisture moves north as models indicate and the track of the storm is west of Provincetown out on the Cape. I am not entirely convinced we can pull off the big event yet but the two things to keep in mind are 1) This is the best chance we've had at decent snow in several weeks 2) We are very likely to get at least some Saturday night and Sunday regardless of what happens later Sunday into Monday.

The light snow Saturday night and the possibility of more significant snow later Sunday into Monday marks the first of what I think will be many chances for powder in a much improved weather pattern. The weakened jet in the Pacific combined with the large ridge extending northward through Alaska will allow the vortex of cold weather to advance southward into Canada. The cold is not indicated to overwhelm the entire pattern as it did over the holiday into the early part of January. We will flirt with danger once or twice but for really good Vermont snow it's kind of necessary. The middle of next week, around the time frame of February 7th and 8th marks one such case since it involves a push of milder weather. Doesn't appear likely however that the mild air will continue its pillage into Vermont; instead, we should get some additional snow and quite possibly a significant amount.

Arctic air will be re enforced around the time of February 9th, giving the end of the week and the subsequent weekend a rather chilly outlook. At least one clipper system should bring the region more snow around the time of February 10th and 11th (the 2nd full weekend in February). A similar theme applies to the week leading up to the President's Day holiday. The vortex of cold weather appears farther north but the pattern still looks promising with the jet stream taking on a more traditional positive PNA shape. A block in the jet stream is likely to take up a position somewhere between Alaska and the North Pole. Where in this range it decides to land will ultimately determine how cold it gets and where the storm track will set up. Right now it looks like Vermont is positioned to do as well as about anywhere in the country.

Monday, January 29, 2018

Got to wait for the turn of the month but our prospects for new snow are looking good, substantially good actually

I saw one person on twitter refer to snow conditions in Vermont as a frozen hellscape. Perhaps, but it does beat out the snow conditions two years ago around this time which consisted of rocks and dirt. Can't promise any improvement for the balance of the month but that amounts to about 2 days. Beginning this Thursday, the first of February, we should start seeing big improvements and several chances for new snowfall.

The jet stream is, as expected, undergoing an amplification but this will yield little if any snow throughout most of northern New England. There will be an area of snow well to the south and west of Vermont on Tuesday but it looks like fools gold as far as we're concerned. This area of snow simply won't successfully move east before dissipating and much of the Vermont high country will see temperatures hover around the 20-degree mark along with some occasional sunshine. Wednesday will feature more sunshine in the morning but more clouds in the afternoon as the pattern gears up to bring the region more arctic air and more snowfall to the region just in time for the turn of the month.

February 1st, the day which looked potentially catastrophic about a week ago, has come full circle from a weather forecasting standpoint. The push of milder weather looks severely weakened. A clipper system well to the north will move through the eastern provinces of Canada and gain minimal amounts of moisture from the Great Lakes with a cheap addition of subtropical moisture. It doesn't sound promising but snowfall prospects have looked better and better over the last 48 hours. I am not promising an epic storm, but even a few inches should help improve the "frozen hellscape". Snow should arrive right around the time February arrives (midnight Thursday) and continue into the day Thursday in sporadic fashion as arctic cold begins spilling into the region. Now the subtropical moisture still has the potential to allow this storm to ultimately become a more significant anafrontal wave with more significant snowfall east of Vermont. If this were to happen, it would be a Thursday night to early Friday occurrence and though Vermont is not positioned to the best to receive a high dose of snow, we certainly could at least get a small dose. In the end, the two days (this Thursday and Friday) that once appeared so mild, now look somewhat snowy with at least 3 inches falling in the high country and probably a bit more than that before Friday evening.

First of what will be a few rounds of arctic chill will encompass the region by Friday and should help dry things out but only for a short time. Some left over energy from some active weather in the Pacific Northwest will advance eastward quickly and both re enforce the arctic cold and provide another chance for new snowfall. Can't call this system a "BC bomber" since it doesn't look like much of a "bomber". Perhaps a "BC badger", but not a BC honey badger since we now know thanks to youtube, how vicious those suckers can be. This system looks somewhat innocent yet still capable of producing several more inches late Saturday into early Sunday. Temperatures will be chilly this weekend, consisting of mostly teens and single numbers on the mountain.

The upcoming pattern, discussed a few times is capable of producing a few weeks of solid winter weather for us. We have a potential inland runner late next week but this system has an even better chance of being a big snow producer. An early look at the week leading up to the President's Day holiday looks pretty cold, anchored well by the negative EPO and a ridge extending up through Alaska into the Arctic.

Saturday, January 27, 2018

Thaw for the upcoming week is basically off the table but snow appears fairly minimal right now

The weakened push of balmy weather isn't going to do much to the several inches of white concrete encasing my yard. The best solution would be to top it with about 30 inches of powder but we're going to have to wait on that for now. Some mixed precipitation will pass through the region Saturday night as expected and the high elevations could see 1-2 inches while it remains mostly wet down low. Temperatures will hover at or just above the freezing mark (depending on your elevation) under a mostly cloudy sky on Sunday.

The fast moving jet stream will amplify Monday into Tuesday. There will be a sizable storm that will remain off the coast and a clipper system that will get ingested into this system late Monday into Tuesday. This process will create the inverted trough setup that was discussed a few days ago with a possible deformation area of snow late on Monday into Tuesday. Most of the available data is suggesting that the bulk of this occurs south and west of the Green Mountains though models traditionally struggle miserably trying to pinpoint these areas outside of a day or two in advance. Our most likely outcome right now is a period of very light snow late on Monday, Monday night or early Tuesday with minimal accumulation with a slight chance for more. Don't hold your breath on this storm though. Not worth it.

The week as a whole continues to appear colder with each passing day. The potential late-week thaw that the various long range ensembles were advertising as "destructive" a week ago is basically gone. Temperatures will hover in the teens on Tuesday, might get back below zero on Wednesday and will very much struggle to reach the freezing mark, if at all, late in the week. That's fantastic news, but we need some snow to go along with that and models are a bit more bearish on that front early this weekend. A relatively weak storm system is expected to get guided out of the southern Rockies later in the week as arctic air makes another southward advance. It's possible this storm evolves into an anafrontal type wave of low pressure but where does it hit or will it fall apart entirely ? I'll seek to answer this question within a day or two but at least we have a "snow or no" situation as opposed to a "how bad will this thaw be". At the very least, the arctic boundary should provide a light accumulation before readings get sent back into the teens and single numbers for the first weekend in February.

Much of the themes discussed a few days ago hold true as far as our outlook for February is concerned. The combination of the falling EPO index (death of the evil empire) and the establishment of a large block in the jet stream north of the Bering Sea will allow arctic cold to cover a good part of Canada and much of the northern tier of the United States. At the same time and in very typical La Nina - like fashion, a ridge across the southeastern states will try and keep the arctic air from penetrating southward to the extent that it did around the holidays and in early January. The result should be some Game of Thrones level excitement. The Lannister army trying to bring their warm weather northward. John Snow (Should I say Targarian ? ) keeping us protected with cold and hopefully some snow. The White Walkers ? I don't think we really want them around.

Thursday, January 25, 2018

More improvements in the forecast over the next two weeks as we approach the death of the "evil empire"

Our general outlook continues to slowly improve as we get closer to February and though some concerns remain in the forecast picture, good news is once again out-weighing the bad. Thanks to the evil empire out in the Pacific, ensembles have, for some time, been keying in on two big potential trouble spots over the next week or so. Though changes are still possible, we may in fact get through both with minimal damage meaning no big rain and no dramatic melt-off. Following a bluebird Friday with seasonable temperatures, we will see readings warm toward the 40-degree mark on Saturday. A weakening weather system behind this push of warmth will approach the region late on Saturday but lets be thankful this storm is falling apart because because warmth will be mitigated and the rain will be minimal. Some precipitation is expected Saturday evening and night but we shouldn't see much; in fact, precipitation in the high country is likely to fall as some wet snow while mixed rain and snow falls in the lower elevations. A few of the very highest spots might actually see an accumulation. Clouds should generally remain in place for Sunday. It will remain mild but not get any milder with readings hovering a few degrees above the freezing mark.

The forecast for next week has been evolving quickly. We still have another push of mild temperatures to be concerned with in the Thursday/Friday time frame (February 1st and 2nd), but this also looks substantially weaker than a few days ago. In addition, the week as a whole looks flat out colder. Arctic air will plunge southward Monday through the Great Lakes region thanks to a jet amplification that has been underestimated by the models until the last two days or so. There's a clipper system associated with this quickly digging trough, some subtropical energy/moisture down near the Gulf and when you mix that up with some incoming cold air, big east coast storms can happen. That's not what models are currently showing, at least not showing a storm capable of delivering feet of snow to New England but that possibility is certainly out there. Models are indicating some snow however but there's been a lot of wavering and dissension about who exactly gets it. My expectation is that the forecast picture for Monday undergoes some additional changes over the next few days but right now, there are indications of an inverted trough and a possible deformation area where snowfall could be significant. If this is what indeed happens, one particular area will do well while other areas might miss out completely. Temperatures will fall back into the 20's Monday and back into the teens Tuesday (with wind chills) and then more sub-zero readings possible on Wednesday morning of next week. 

The big changes in the pattern are happening in a few different locations. The evil empire will get beaten down as we approach February 3rd and 4th and EPO index forecasts are illustrating that with the expectation of some significant negative values within two weeks. We also have a large high latitude block in the jet stream that is expected to form over the Arctic Ocean centered north of far northeast Russia. The combination of the aforementioned developments will allow for a big southward push of arctic air which is anticipated to reach Vermont by first full weekend of February. We have the warm-up already discussed around the 1st or 2nd of the and we may see a little rain before the mild weather is displaced. I will point out however that there are hints that the front responsible for the cold air arrival may also bring some snow along with the minimal amount of rain. Its a long story that I'll save for the next update if this song remains the same.

The position of the high latitude block is located a bit farther north and west than one would consider ideal for eastern North American cold. Ensembles have actually indicated over the last two days that the center of the strongest cold will actually be well west of Vermont during that first full week of February. Though this does open the door for a possible inland runner even after we get cold, it will also ensure that the pattern isn't overwhelmed with cold with a storm track that is too far south for New England snow. The best patterns for snow in Vermont are typically the ones where we flirt with danger and this looks like one of those situations. It's been a frustrating few weeks but February looks very encouraging. I expect some exciting stuff.

Tuesday, January 23, 2018

Much less warmth and possibly even some snow late this weekend and an even better looking longer term February outlook

Sleet, freezing rain, rain and some above freezing temperatures is not what the doctor ordered during the climatologically coldest part of the winter. Snow returns to the high elevations late Tuesday evening and by Wednesday morning, the entire region should be seeing some flurries and the high country should have a fresh 1-3 inches on the ground along with temperatures in the 20's. Accumulations are likely to be more robust as one heads north and could reach 6 inches at locations such as Jay Peak.

Don't let your spirits get too dampened both literally and figuratively because good news encompasses the outlook today. Just a bit of it in the 5-day outlook and a lot more of it in the longer term outlook (two weeks out). Challenges remain on the horizon but I consider them a sunk cost at this point.

Cold will gradually build across the region as the current week progresses. Readings will take a run at zero Wednesday night and will be confined to the teens Thursday in spite of a full day of sunshine. The dry and somewhat chilly temperatures will continue into Friday though readings should at least approach the 20-degree mark during the afternoon. The SCWB has certainly expressed some concern about the upcoming weekend for some time. This appeared to be the height of the "evil empire" and it's sinister prowess in regards to the general impact on snow conditions in Vermont. Though it still appears mild relative to average this weekend, the intensity of the relative warmth appears much less based on the last few cycles of model data (perhaps only 30's on Saturday). This in itself is excellent news, but perhaps we have room for additional positive headlines. A storm system is expected to approach late in the weekend, fueled largely by the push of mild air to our south and the pool of arctic air positioned over eastern Canada. There's a broad possibility of end results with this storm but it's looking increasingly likely that we can score some snow in the Sunday/Monday time frame. Other forms of precipitation remain possible also but this is a massive improvement relative to the dire picture the ensembles were painting for the last weekend in January several days ago.

We've got another (and hopefully last) big roller coaster ride on temperatures in the subsequent week. Cold weather makes a temporary push south during the early part of the week ensuring sub freezing temperatures in the Monday-Wednesday time frame. Milder air will then make another northward push late in the week in what I hope will be the last trying situation before we head into an extended period of wintry weather starting around February 3rd or 4th (first weekend of Feb). It remains to be seen how mild we could get on February 1st or 2nd and whether or not we get a major rain event. At the very least, 1-2 days of above-freezing temperatures is likely.

So the turn toward colder and more wintry weather is coming into view. The MJO is cycling quickly and the ridge across the mid-latitude Pacific is expected to weaken and become a more full latitude ridge extending up toward the poles from the eastern Pacific. This will will arctic air to make a southward push and greatly reduce the probability of extended thaws and rain events starting a few days into February. It is possible that one more such event could occur before February 6th but significant snow is also possible in that time frame.  A somewhat weakening La Nina parlayed with cold centered across the central part of North America is certainly the right kind of ingredients for a stormy eastern United States. Snow conditions should thus improve at least gradually and possibly quite dramatically.  Lets hope !

Sunday, January 21, 2018

Mixed bag of precip late Monday into Tuesday and outlook remains less than ideal through very early Feb

Precipitation looks like it will arrive rather quickly Monday from the upcoming storm system, perhaps even before evening. Thanks to a late arriving push of arctic chill, precipitation will fall as snow or a snow/sleet mix for a few hours before going to a sleet and freezing rain mix late in the evening. I'll give NWS Burlington some credit on this. They were forecasting a warmer storm and for the most part stuck with it and models have somewhat trended in that direction. It won't be the washout that occurred two Friday's ago; in fact, only a minimal amount of rain is expected during the day Tuesday with some freezing rain in a few spots. Temperatures in most places will find their way above freezing during the day, albeit only by a few degrees. Both colder air and some accompanying instability will arrive Tuesday evening and we should see some snow as a result but accumulations look more probable farther north and my initial guess is for 1-3 Tuesday evening into early Wednesday.

Our outlook remains rocky through early February and that includes at least one additional surge of warmth during the last weekend of January. Arctic cold will actually reassert itself over the region temporarily late this week but will give way to the warm weather beginning late on Saturday Jan 27th. Models have lessened the intensity of the warm surge somewhat and some arctic chill remains a few hundred miles north over eastern Canada; nonetheless, Sunday looks like a torch and Sunday night and Monday look both very mild and rainy. Still some time to modify this forecast but if it holds, we will manage to have the coldest January in 3 years yet still end the month with less snow than when it started. Only in New England ! At least the Pats made the Super Bowl again (though I am not a Pats fan so I can't share in that enjoyment, but congrats if you are).

There are signs of a shift but they remain way out on the horizon. As mentioned in the last update, we will likely face one more somewhat adverse weather situation at the beginning of February with a move toward move consistent wintry weather after that. The evil empire remains a problem but the MJO is cycling and will be finished with the "warm" eastern North America phases around the time of February 5th if one would extrapolate the cycling. The MJO is a complex larger scale weather phenomenon to explain but warm phases can certainly induce the development of the so-called "evil empire" while cold phases can kill it. I know it's frustrating but we'll get trough it with a little patience.

Friday, January 19, 2018

Tuesday's storm looks more wintry but outlook for back part of the month continues to look a bit rocky

Cold in the deep south managed to mostly avoid New England this week and temperatures were wintry but seasonable. We've gotten bits of snow here or there but certainly could use a bit more. The giant ridge in the jet stream across the mid-latitude Pacific Ocean that I commonly refer to as the "evil empire" will continue to provide challenges for the balance of the month and perhaps even into early February. I do think that it will ultimately become more favorable as we progress into February but we'll have to be patient until then.

Fortunately, we can enjoy a bit of good news in the short term. As advertised in the previous update, the Tuesday storm system looks more wintry and not particularly rainy. The region will enjoy a bit of mild weather Saturday (about 40 degrees), a rather mild night Saturday night (30 degrees) and a relatively balmy start to Sunday, but arctic cold will indeed make its New England-only sneak attack forcing temperatures lower Sunday night and ensuring a cloudy and more seasonable Monday. Precipitation arrives late Monday night and should arrive in form of snow; in fact, we should be able to score a few inches by Tuesday morning when at that point we are at risk of a change to sleet/freezing rain. As of early Friday, NWS Burlington is forecasting plain rain during the day Tuesday, essentially following the warmer American GFS model which has temperatures approaching the 40-degree mark. Other models are suggesting a colder storm and I am going to continue to ride that bandwagen. After a few inches of snow Monday night/early Tuesday, most of the daylight hours Tuesday will be sub-freezing with sleet or freezing rain (I am just nor sure which yet). Locations such as Jay Peak, have a 50/50 shot of staying all snow for the event. The models suggesting a colder storm are also suggesting a decent pool of low level instability Tuesday night capable of providing the ingredients for terrain induced snow showers of the accumulating variety. In the end, we might not see the very skiable fluffy snow from this storm, but we should get another layer on the foundation and we're going to need it because more challenges lay ahead.

Seasonable temperatures return to Vermont by Wednesday and snow showers should continue for a time before tapering to flurries while clouds decrease. The wintry temperatures should continue the balance of the week including some morning sub zero temperatures by Friday (Jan 26). Like I mentioned however, the Evil Empire is still at work and plans on sending us another big surge of mild weather during the last weekend of the month. Arctic cold will linger in south central and southeast Canada providing some hope that we can stave off another thaw but this will be one of the bigger challenges in this pattern before it hopefully gives way to a more favorable setup in February. In addition to the surge of warmth/potential rain during the last weekend of January, there is likely to be one more in very early February. I am not guaranteeing another rain event but it's possible along with another 1-3 day stretch of above-freezing temps.

Tuesday, January 16, 2018

A fluffy 3-5 Wednesday and a somewhat more wintry outlook after that though far from ideal

The Mad River Valley and the mountains that surround it have that wintry feel yet again, but there's work to do obviously. Though the mid-week storm that once had such potential will not deliver what was hoped, it will deliver something. We already received a nice 1-2 on Tuesday morning and snow is expected to recommence Wednesday morning and continue at a relatively light but not entirely insignificant rate throughout the day. Southern Vermont, the Monadnock region of New Hampshire and much of Massachusetts will perform somewhat better from this rather compact system, but we won't be left out. Accumulations will be of the fluffier variety and should amount to 3-5 inches by the time the day ends. Seasonable temperatures finish will follow for Thursday followed by a Friday where readings inch their way toward the freezing mark. Snowfall is expected to be minimal both days but flurries or some light snow is possible Friday in front of our next push of warm air.

The evil empire in the Pacific has some challenges in store for us over the next two weeks or so. The first comes this weekend into early next week but their are some interesting developments that appear more evident over the last day or so. We have some agreement that Saturday is a torch but a dry torch and not an excessive torch. Temperatures will make a push toward 40 thanks to a mild wind, but clouds will help keep readings from spiraling too far upward and both rain/ high dewpoints are not expected. The above-freezing temps are expected to persist through early Sunday but there are indications that our friends in Canada will send a "New-England-only" shot of arctic cold. Models have yet to converge on this but I am relatively confident it occurs and it comes by late in the day Sunday. This has some pretty big ramifications on a weather system that is expected to impact the region early next week. Their are indications of another 45-degree rain, but I don't think we get a repeat of last Friday. Instead, temperatures are likely to fight their way below the freezing mark Sunday night, setting the stage for an icy situation Monday night and Tuesday. Interestingly, the European model has really come around on bringing the arctic cold to the rescue the last two successive model runs; in fact, some snowfall isn't that far out of the picture and is probably in the picture for areas such as Jay Peak. This situation is worth watching as it seems to be evolving quickly and in a generally positive way for us. Ice isn't ideal but it sure beats another meltdown. There are probably some mild forecasts still out there for Monday/Tuesday but my guess is that we will trend colder and hopefully continue to trend colder as we get closer to the event in question.

I think the Monday/Tuesday event is a microcosm of what we will be dealing with for the back half of January. The evil empire will throw a few challenges our way, but the giant ridge in the Pacific, though a rather significant player on the playing field, is not as ferocious as some others in past years. We are likely going to have some additional mild excursions but I also expect that we add some new snow on a few occasions and might even be able to score a significant storm before the end of the month.   One such chance for this might come around the time of the last weekend of the month, but it's anybody's guess as to what kind of precipitation might fall. If the MJO continues to cycle, as its been cycling, we will have a chance at another sustained round of wintry weather in February.

Sunday, January 14, 2018

Potential mid-week storm probably belly flops leaving us a bit snow-starved in a less than optimimal weather pattern

We took an old fashion @#%kicking Friday and got a layer of freezing rain, sleet and only a little snow for our troubles. Sleet makes for terrific foundation material and were we to get a nice 6-12 inches of fluff on top of all that, I wouldn't expect too many complaints. Alas, the snow forecast for the next week isn't what I had hoped and it may take much of the rest of this month to get this pattern to a place where those type of events can occur.

The Martin Luther King holiday Monday will be a calm and cold one. Temperatures will start near -10 and make a modest climb into the teens thanks to a full day of bright sunshine. Tuesday will be cloudier and not as cold with readings climbing into the twenties. We had eyes on the middle of the week since it was expected that a potent clipper system might work a bit of magic along the eastern seaboard. This system has the capability of giving us a full replenishing. Sometimes I like the think of clipper systems as olympic divers though many fall well short of olympic material. This clipper system takes a graceful jump off the diving board and as of now is indicated to belly flop off the Middle Atlantic coastline. The advancing and building ridge in the middle of the country just looks to be coming at it too hard, not giving it an opportunity to strengthen and take a northeast turn. There's still a small chance to turn the ship around and a bigger chance that we can score a few fluffy inches Tuesday night but concept of a big mid-week storm looks almost dead.

And then we have the evil empire to contend with. The tightened jet stream in the Pacific is expected to be with us for at least two weeks beginning in a few days and that will pose an invariable hurdle for much of the back half of January. Not to say we can't jump that hurdle on occasion but we won't always be able to jump it. Mild weather will make a big run at the region starting Friday the 19th and will push temperatures past the freezing mark during the weekend of the 20th and 21st. Limited amounts of cold air in eastern Canada might be able to work it's way into the weather picture in time to stave off another potential rain event on the 22nd but that could go either way. Colder air will work its way back into the region for the 22nd to 24th but the storminess and cold will be focused on the western U.S. where many areas have been snow-starved and need some help from a few storms. Unfortunately the door will remain open for another less than optimal weather situation prior to the last weekend of the month. I do think the weather pattern will ultimately turn more favorable but we're going to need to be patient for now.

Thursday, January 11, 2018

Sleet and some snow follows the thaw early Saturday but it looks much more interesting during the middle of next week

Given the approaching Martin Luther King holiday and some potential snow on that holiday, thought it would be a good time for a supplemental update. The thaw is smacking us around pretty good and nearly an inch of rain, 50-degree temperatures and wind will do some serious damage to the snow pack by Friday night. Most of the rain will fall in the midday hours Friday and it will come fast enough to cause some miner flooding given the still frozen ground and the melting snow. A return to sub-freezing temperatures comes very dramatically after about 8 PM Friday. Any rain will likely become freezing rain before midnight and then become sleet after midnight. The incoming cold is undercutting the lingering warmth associated with this storm allowing precipitation to continue well beyond the passage of the front. It also means it will take some extra time to turn that precipitation to snow. We've got some good news in that the 2nd wave of low pressure, associated with this storm will track further southeast and this gives us a longer opportunity for snow following a period of sleet early Saturday morning, but as of now, it doesn't look like a huge accumulation - about 2 - 5 inches on top of a layer of sleet. Temperatures will be back in the teens by Saturday and back below zero by Sunday and Monday mornings. Afternoon readings Sunday and Monday should be about 10 degrees and lower than that at the summits This initial shot of cold looks rather stable unfortunately so we should see lots of sunshine and little in the way of new snow after what falls Saturday.

The setup for the middle part of the upcoming week looks wildly interesting. A very potent jet stream impulse will rotate through the Great Lakes Monday and advance to the eastern seaboard Tuesday setting the stage for a highly dynamic situation. The weather feature will bring some cold weather as it drops southeastward out of Canada, but in this instance, there isn't a polar vortex or a strong separate polar jet to disrupt storm development along the eastern seaboard. The jet may in fact close off close to the Atlantic Coast before lifting northeastward late in the week. Not only is this conducive for a storm, it's also conducive for a slow moving storm. In addition, we should see a healthy pool of highly unstable air once the storm passes unlike the shallow, very stable cold that has held down snow totals in Vermont during the recent cold wave. Now there are numerous ways we could whiff. The storm might not materialize or it might form too far south and stay south.  The pool of instability I am so giddy about might also fail to deliver as they often do. At the very least however, we should keep an eye on the weather happenings between Tuesday and Thursday of next week. The mild weather is pulverizing for the time being but we could make a very quick recovery. 

Wednesday, January 10, 2018

Thaw ends as sleet and some snow Saturday and the outlook after that looks a lot less bad

Wednesday marks the last day in what has been a long stretch of sub-freezing (in most cases, way sub-freezing) temps on the upper mountain. It's certainly been a good one with plenty of sunshine and calm winds. Thursday will feature more clouds but a mild wind will pump warm air into the region rather effectively and temperatures will push into the 40's, even way up on the mountain. Fortunately, Thursday is relatively rain-free. We may see a few sprinkles here or there, but there are no indications of significant areas of precipitation. This all changes of course Thursday night into early Friday as a somewhat split, but formidable weather system approaches from the west. More or less, this is the same storm responsible for the mudslides in California and it will pick up additional moisture from the Gulf of Mexico. Given the warmth, this isn't exactly good news. Rain will begin in the very early morning hours Friday, get rather intense during the morning hours and then taper off during the afternoon. The mild erosive wind will continue, pushing temps in to the 50's in some areas and damaging the snow pack. It won't all go away but a half to 3/4 of an inch of rain, high dewpoints and wind can do some serious damage. Fortunately the rain will be over by Friday evening and arctic chill will push readings downward  Friday night.

Our storm will have a 2nd act in a two part series - an even stronger area of low pressure that is expected to bring it's precipitation after arctic arctic air is somewhat re established over Vermont. This 2nd area of low pressure is expected to track northeastward either across Vermont or somewhere closer to the southern New England coastline. We would strongly prefer the latter option but this is a critical question that remains not completely answered. When precipitation re commences early Saturday morning, temperatures profiles in the lower troposphere suggest it will be primarily sleet with some freezing rain. As the day progresses, this precipitation will gradually change to snow and we should see a period of that before Saturday night. The extent of the snow depends heavily on how far south, this 2nd low pressure area decides to track. An optimal track, close to the southern New England coastline, will bring us several inches after some morning sleet. The consensus of information suggests a hefty sleet accumulation and only 1-3 inches of snow. In any case, a big sleet accumulation isn't the worst thing following a thaw/rain. We'll get another layer on the foundation and hopefully go from there.

We get back into the cold for a time following our series of precipitous days; in fact, the cold looks far more impressive than the various long range indicators suggested a few days ago and especially a week ago. As it turned out, the demise of the jet stream ridge across the Yukon was  greatly exaggerated. Though it looked as if it would be part of the general weather picture, its overall impact was downplayed by the longer range ensemble simulations. In the case of the European Ensemble simulations, it will prove to be one of the biggest temperature busts I've seen. In Vermont we will see a series of days with high temperatures only in the teens and low temperatures below zero. Not quite the intense chill felt a few days ago but still below normal climatologically speaking. There's also a weather system to watch, a clipper, that will advance into the Great Lakes late Sunday into Monday and potentially impact the east coast on Tuesday. This clipper is associated with a potent jet stream impulse, one that has the capability of working a bit of magic along the east coast. The impact on Vermont remains to be seen but it's worth watching.

The cold weather lingers through Thursday the 18th and then we anticipate some further tightening in the jet across the Pacific allowing the evil empire to emerge. There are levels of "bad" however and over the last few days the impact of this rather adverse pattern appears less bad. The Arctic and North Atlantic Oscillation (AO and NAO) will remain neutral to even somewhat favorable and when takes a measure of this "Evil Empire" through the lens of the MJO/EPO, it certainly could be worse. The EPO is only moderately positive and the MJO, though not in the most ideal phase of it's cycle, could be worse. It's very important to keep the competing forces around as opposed to getting overwhelmed with an extremely negative one. It looks more and more as if we may in fact do that meaning any thaw will be very minimal while at the same time not entirely killing the prospects for new snow. 


Sunday, January 7, 2018

As the cold retreats, the outlook appears less than desirable but some potential remains for the upcoming weekend

The extreme cold is finally relenting and it was hoped this would yield to the right kind of storminess. We do have an interesting potential scenario this weekend but honestly I can't say this was the transition I was hoping for, at least as it looks now. We have some snow in the real short term to enjoy. By the this gets read by most (tomorrow morning), we should have 1-3 inches of snow on the ground. Later Monday, another disorganized area of snow should bring an additional 1- 3 inches. This is not a very imposing clipper system but it has some similarities to the event which brought the 6-12 to the high country north of I 89 ( Stowe, Smuggs & Jay) a few days ago so I wouldn't be surprised to see a localized area with more while other areas underperform.

Both Tuesday and Wednesday look especially comfortable days relative to the recent stretch of weather. The extreme arctic cold will have retreated and after some morning clouds and flurries, afternoon sunshine will push temperatures toward the 30 degree mark. Wednesday will feature even more sunshine, calm winds and temperatures near the freezing mark. Great day to hit the slopes before we get gut punched.

This initial surge of warm weather I have taken particular exception to. We have a terrific accumulation of arctic cold weather in Canada and a series of teleconnection indices that are not especially unfavorable, yet a series of unfortunate events may bring temperatures well into the 40's by late in the week, accompanied by a significant round of rain and snowpack eating wind. I am just begging the storm system in question to break up, but it seems intent on bringing excessively mild air into New England. There are some recent signs of a split and this would set up a somewhat more interesting series of events by the weekend. The initial surface wave seems like a lost cause, it will head into southern Canada and bring a round of warm weather and rain to the region Thursday into Friday. The timing on the rain appears to be Thursday night or Friday morning. Arctic cold will then try and heroically make a southward push and re establish a tenuous grip on the region during the weekend while the 2nd more potent system approaches. This 2nd storm is stronger and may get an added stimulant from a digging jet stream. There are questions relating to the timing of the jet reorientation and models are thus all over the place on the outcome but significant precipitation is likely for the upcoming weekend, we just don't know what kind yet.  Canadian and American ensembles are bullish on the possibility of significant snow, Euro and its ensembles seem to be in the rain to limited snow camp. We should have it sorted out within a day or two.

In the wake of whatever kind of storm we get, cold weather will burst on the scene Sunday and Monday (Jan 14th -15th)  and should be accompanied by some snowfall. The snow could come as a result of the terrain/lake enhanced stuff or from a clipper system advancing through the region early next week. The cold air is not expected to grip the region for long however and you can thank our evil empire in the Pacific for that. Whether this amounts to a significant January thaw or another day or two above freezing remains to be seen, but we need the massive ridge in the central Pacific to break down quickly to avoid significant damage between the 18th and the 22nd of the month. If you follow the weather more avidly, you might be familiar with the MJO (Madden Julian Oscillation) which describes, in phases, the cyclic nature of convective activity in the Pacific. This activity has the capability of impacting the evil empire which is why forecasters focus their attention on it. The MJO is expected to stall in the less than favorable phase 3 territory which may be why the potential round of mild weather appears so ominous. Fortunately, these long range forecasts don't always work out. No, it doesn't look great now but lets keep revisiting the question as time advances. 

Friday, January 5, 2018

Been a cold, snowy and exciting start to winter but trouble lies ahead

Some good news and bad news on this first Friday of 2018.  Relative to about any place in the country, winter has raged the hardest in New England. Near record-breaking cold, epic East Coast bombs and 50-below wind chills, we've certainly done it right so far and have a decent early January base of snow to show for it. Trouble is staring at us in the face however and it seems to be getting worse and worse with each new round of data. We have some good news with the storm early next week, which appears disconnected from the warmer southern streamer, albeit weaker. This will extend the stretch of sub-freezing days on the upper mountain to over a month. After that, there's all kinds of trouble. The jet stream in the Pacific will tighten some and blocking will weaken some, which in itself isn't all too terrible. Then the jet stream in the Pacific will tighten further and the blocking completely vanishes. It all boils down to two glaring trouble spots over the next 2 weeks or so.

Unless you've been asleep for 2 straight weeks, you are well aware of the intense cold this weekend. Saturday still appears blustery but not quite as bad as Friday and sunshine should make an appearance. Winds will subside further Sunday with temperatures inching above zero late in the ski day. 5 degrees, less wind and a little bit of sun will feel balmy after the last two weeks. Monday's storm system is really nothing more than a clipper. We should expect some periodic light snow throughout the day.  The disconnection with the moist southern streamer means less precipitation and therefore less snow, but it also means no freezing rain. A modest 2-5 inches is my first guess right now followed by some terrain induced snow Monday night  into early Tuesday.

The back half of Tuesday into Wednesday appear relatively tranquil and certainly a lot milder than our recent stretch of weather but not yet above-freezing. If your looking to hit the slopes ahead of any warmer weather, Wednesday might be the day to do it because the end of the week appears to be the first potentially problematic scenario. The weather pattern appeared capable of at least partially resisting a dramatic capitulation of cold. Recent modeling has consolidated some slow moving jet energy in the southern plains late next week while the polar jet both recedes and flattens. Not sure I am completely sold on this outcome but it would be a bad outcome, with mild air flooding northward all the way to the St Lawrence Valley.  A less consolidated system might still allow for a day or two of mild weather but arctic air would remain close enough to give us a fighting chance. Almost everything I've examined suggests some rain late next week and at least a day of very mild weather. There's a chance it could get really mild and really rain.

January 17th -20th appears to be the other trouble spot on the somewhat foreseeable horizon.It's the "Evil Empire" making, its first appearance since October. For our newer readers, my "Evil Empire" is a giant ridge in the central mid-latitude Pacific Ocean that acts to tighten and flatten the jet stream in the northern latitude Pacific. This forces arctic air into retreat mode every time and is likely going to mean a second round of very mild air. In between the mild air late next week (ending Jan 13), and the mild air late in the 2nd week (ending Jan 20, there are indications of a jet amplification and a potential storm capable of delivering snow or at least precipitation. The time frame for that is Sunday-Monday January 14th and 15th.

Wednesday, January 3, 2018

Monster storm track shifts west and Mad River glen benefits with at least 6 inches, possibly much more

There's a scene I remember from the first Lord Of The Rings movie where Gandalf is explaining the Ring of Power to Frodo. The line goes something like this - "The Ring is always trying to get back to its master. It wants to be found !! Though certainly implying nothing sinister, this is more or less how I view the relationship many east coast storms have with the Atlantic coastline. Storms want to track along the coastline, they want to be found. There's lots of physics behind this but I prefer the Lord of the Rings analogy on the blog and leave it at that. It's upgrade time !

The expected track of the storm has shifted and it could shift even further given the time left before verification and the difficulties models are having dealing with the subtropical moisture and the area of low pressure that is expected to form out of that moisture. The storm was expected to track 100 miles or more east of Cape Cod, now there are indications that it will track roughly 50 miles east of the Cape. It's possible, that by tomorrow, the storm could be tracking right over the Cape. It's an old fashion "humdinger" also, causing severe winds, power outages and maybe some coastal flooding in certain areas. For Mad River Glen, the result is snow. Perhaps we aren't in the best conveyor of snow but I wouldn't discount any possibility given the way the situation is evolving. Snow should begin in the midday hours Thursday, get rather intense for a few hours in the evening and taper to light snow by Friday morning. Even if we don't get into some of the deep moisture, we will certainly get into the big winds. Ferocious !! Especially Thursday evening and night. If the snow was wet, we would have power outages. Of course, it won't be with temperatures around 10 degrees. Snow will be wind blown but accumulations will range between 6-16 inches. This is a rough guess and perhaps on the low side given the trend. If the storm decides to track west of the Cape, we will be looking at a 20 incher.

A massive area of cold will get pile driven into New England in the wake of this monster storm as expected. Though I do expect flurries or light snow throughout the day Friday we are still dealing with some very shallow, stable cold which prohibits the big upslope snow accumulations. We may see an additional inch or two but of greater note will be the wind-driven nature of the snow accumulations given the blustery conditions. Good opportunity to find that favorite spot in the woods and stay warm, with temperatures hovering slightly below zero.

Upcoming weekend consists of a totally sub-zero Saturday with readings starting near -20 and only climbing to -10, a somewhat sub-zero Sunday with readings starting near -20 and perhaps rising to 5. Sunday will be the calm day with some sunshine to start and some clouds to finish. The clouds arrive in advance of our next weather system which to the naked eye looks somewhat innocent but is full of moisture. Unfortunately, it's full of a big push of mild air with just some minimal push-back from the retreating cold. We should see some snow to start and perhaps some snow to finish and perhaps some ice in between or perhaps not. No place can do -20 to rain (in this case freezing rain) quite like interior New England and Monday and Monday night might be another such instance. That said, we should see accumulating snow as well and it's not a given we see the ice, just possible.

An area of cold will re establish itself over New England later in the week and there is an opportunity for some snow as this is happening either Tuesday or Wednesday. Beyond that however there are glaring signs of a massive warm-up across the United States. New England is on the edge of this and is also on the edge of what should be a lingering area of cold in eastern Canada. I am not going to lie, we will probably get at least a 1-2 day thaw out of this but hopefully its just 1-2 days.

Should be a fun storm though even if it  is only 8 inches and obviously it could be more.

Monday, January 1, 2018

On to 2018, which will start with a big storm (but likely not big snow) and more big cold

Happy 2018 folks. We sent 2017 off on a frozen, bone chilling, ice blast. It's been the most impressive cold wave to hit interior New England since 2004, besting even the readings experienced during February of 2015. On the mountain, nearly every hour of the last 5 days of the year were spent below zero and obviously it felt a lot colder with the added effect of the wind. As expected, the PV smashed our chances for new snow. Too much shallow, stable cold the surface and way too much jet energy aloft aimed in the wrong direction.

But as Bill Belichick might say, we're on to 2018 and there is plenty to discuss in the upcoming 10 days. Subtropical energy off the east coast of Florida will allow a low pressure center to form and deposit snow in some highly unusual locations such as Jacksonville, FL or Savannah, GA or Charleston, SC. The storm will start as a relatively innocuous system but as it continues to move up the coast Wednesday January 3rd, it will gather strength and ultimately receive a giant infusion of polar jet energy in the form of an eastward advancing clipper system. And then it's bombs away and I mean big time ! We've seen some big storms in the 12-year history of the blog but I don't remember anything quite like this in the winter season. There are some indications that the storm could deepen to 950 mb south of Nova Scotia. To put this in perspective, the Valentines Day Storm of 2007 was around 977 mb and our Ides of March storm this past year was about the same. Historic Hurricane Irma strengthened to about 915 mb and Superstorm/Hurricane Sandy was in the 945 -950 mb range.

Models have converged on a track that is a big too far east for big snow in Vermont. Given the storms power, this is somewhat fortunate for coastal locations who will nonetheless get some severe winds. The track has trended a bit farther west the last two days but remains on the order of 100-plus miles east of Cape Cod. In spite of this, the massive size of the storm and the decaying conveyor of moisture from the clipper system should allow some light snow to fall across Vermont. Snowfall looks to be in the 2-4 inch range right now Thursday, Thursday Night and early Friday but the window remains open just a crack for big changes in case of a big shift in the track of the storm. Terrain/lake snow again looks minimal later Friday and Friday night as another massive surge of cold gets pile driven into New England. This late-week cold blast may take the crown as the coldest of the season with readings as cold as -25 during the upcoming weekend. The shallow, stable nature of the cold though is what kills the oragraphic snow so barring a big change in the direction of the storm, new accumulations over the first week of 2018 appear minimal.

The jet stream is still expected to relax somewhat but not entirely after January 6th. We don't want a total capitulation, we just want the polar jet to loosen its tight grip just a bit and we should get exactly that around the time of January 8th. That particular Monday-Tuesday time frame appears to be the period where we receive the impact of our next weather system. A bit early to tell what effects this system might bring  to Vermont but at least some snow is likely. More cold is also likely in the wake of this storm for a few days before we could get tested with a more significant push of milder air.

The middle of the month looks intriguing. There have been indications for some time that a thaw is possible but ensembles have shifted somewhat and are now suggesting that a jet stream ridge across western North America stretching north through the Yukon and into the Arctic might be equally influential. Because of the latter, cold air will be plentiful in eastern Canada and I would expect any mild push of air to receive some rather stout resistance. When met with the right kind of resistance, pushes of mild air can mean additional snow. In summary, I still expect a day or two of above freezing temperatures and some non-snow type precipitation though no major thaw during the middle of the month but significant new snow is also likely. Typical northern New England January weather when you truly break it down.