Think Snow, Tweet Snow !!!

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.