Tuesday, February 28, 2017

Colder weather on the way but can we get rejevunated ?

Another "corn horn" is sounding through the Single Chair towers as the month turns from February to March. No doubt that "corn" can be nice to ski but the mountain could use some serious rejuvenation if we plan to extend our skiing through much of the upcoming month. Colder weather is certainly on the way but we need the snow as well.


March starts out with another day of excessive warmth. Rainfall forecasts have diminished somewhat in the last few days. I would expect a small amount Tuesday night followed mostly by intermittent showers throughout the day Wednesday into Wednesday evening. Mild breezes will help to efficiently mix out the atmospheric warmth and push temperatures well into the 50's. Though we were turn dramatically colder by Thursday, the wave of low pressure that I was hoping would help deposit some snowfall on the northern half of Vermont is not materializing quite as I had hoped. The snowfall will happen but most of it falls over Quebec north of the St Lawrence River. What is further insulting is the vigorous jet stream short wave that will pass well to the regions south Thursday night and Friday bringing snowfall to areas such as Washington D.C.; a place already seeing an early start to another growing season even a few cherry blossoms. The jet stream feature responsible for Mid-Atlantic snow will also rob the region of some of the potential low level instability. We will see some snow showers Thursday that will amount to a few inches along with temperatures hovering in the high 20's. Friday will only feature flurries however, along with substantial amounts of sunshine. Temperatures Friday may struggle to get into the low 20's along with strong winds.


As promised, we will have a wintry weekend. Saturday will be the chilliest day (and blustery) since early February with temperatures starting below zero and only reaching the teens during the afternoon in spite of more sunshine. Bit and pieces of some of the intense storminess in British Columbia will then begin to travel in our direction. One rather small piece will bring clouds and some snow later in the day Sunday or Sunday night. This rather putrid looking storm system may be our most definite chance for snowfall in the near term. Though we could see a 3-6 inch event, the storm will also bring with it a push of warmer air and temperatures are expected to moderate somewhat Monday and Tuesday.


This brings us to the questions relating to our more significant Tuesday system. This is the more significant part of the British Columbia stormy onslaught and there are certainly concerns that this low pressure will become too wrapped up and amplified too early. That said, the storm could also amplify, occlude and arrive in a weakened state on Tuesday March 7th. Though this would remove the possibility of a 2-foot snowfall, it would also thwart the possibility of another big mild surge of air. An occluded storm also brings with it a healthy pool of instability which could set the stage for terrain enhanced snowfall on Wednesday and Thursday of next week. I am inclined to think this is the most likely scenario for next week. Mixed bag of precip Tuesday and then snow and winter-like temperatures Wednesday and Thursday.


Colder air should remain in place through at least March 10 and then long range indications are mixed. Milder air is expected to again dominate the middle part of the United States but parts of the northeast could remain mostly wintry through the middle of the month.



Sunday, February 26, 2017

More rain in the days ahead but March 2nd - March 14th look mostly wintry

I owe the SCWB community a bit of a"Mea Culpa" for the "heated" meltdown we just experienced. Yes, yes, I predicted both some mild weather and some rain but certainly did not expect such a historic run of temperatures. We saw plenty of sunshine when more clouds were expected and the mild breezes effectively mixed down some of the excessive atmospheric warmth that many of the models had suggested would remain aloft. 4 consecutive days of 50-plus temperatures is astonishing in late February for the Mad River Valley and would probably be more so were it not for the fact that we experienced a similar run of temperatures in early March last year and an even more anomalous stretch of weather in March of 2012. I hesitate to use the word "unprecedented" because our recorded history is very short relative to a span of geological time but a few generations of data was blown out of the water across the entire eastern seaboard including Vermont.

All that is over for the time being but an event as anomalous as that is apparently worthy of an "aftershock" and we will get one during the middle of this week. Clouds will advance into the region Monday night and though the region might see a brief period of snow very early Tuesday, most of the day will feature gradually rising temperatures which will set the stage for multiple periods of rain. One which should hit Tuesday night with temperatures in the high 30's and another milder rain later on Wednesday with temperatures well into the 40's. This system is a strong one and is expected to continue to strengthen as it moves off into the Canadian Maritimes. A wave of low pressure along the storms associated cold front is the feature that might bring snow to the mountain very early Thursday. Models have been waffling around regarding snow amounts from this particular feature and the overall prevalence of this feature. For the time being, I am still willing to suggest that 6 or more inches of snow is possible early Thursday but models have moved away from this scenario as of late Sunday.

Although we are experiencing delays in the long expected return of winter, a return is still expected. Some decent, though not overwhelming fundamentals should also ensure that it should remain in place for a period of at least 10 days beginning March 2nd.  We should see some fresh snow from a clipper-type system during the first weekend in March but a more significant weather system should impact the region during the March 6th -7th time frame. This system is a product of some of the intense storminess that is expected late this week and over the weekend over British Columbia. If the system in question over-amplifies in the middle of the country it could suck some mild air into the region but unlike the recent stretch of weather, we have some available cold air and a somewhat negative NAO. These ingredients could provide some fireworks and even a less than ideal scenario could result in some significant new snow. Beyond March 7th, I think we can expect at least another week of wintry-like conditions. I understand that the damage to the mountain has been rather substantial and that it will take substantial snows to restore conditions to prime form. Its possible for sure but we do need to catch a few breaks which may be asking a lot at this point in the season.

Friday, February 24, 2017

Winter getting closer to a full return follwing extended thaw

The corn horn has been echoing through the Vermont high country this week as temperatures have surged and in almost every case, bested expectations. Valley locations saw 60-degree readings and the hills saw readings surge into the 50's. If you like the warm, soft snow, you basically have one more solid day to enjoy it Saturday. We have weather system approaching and this will bring a very well-defined line of rain, perhaps even a thunderstorm to the region but the ski day is expected to remain mostly dry with the exception of a few sprinkles. Strong southerly breezes will help push temperatures into the 50's again.


I expect a quick half inch of rain Saturday night beginning within a few hours of 8 pm. Interestingly, the latest model data has trended a bit toward a more anafrontal system which means the incoming cold will undercut the area of moisture. This will allow for a brief window where snow is possible starting around midnight and persisting for 1-3 hours. 1-2 inches  of snow and a return to sub-freezing temperatures will greet the Mad River Valley Sunday morning but temperatures should again climb above freezing in low lying areas as the cold weather isn't particularly intense. At the summits, I'd expect temperatures to remain below freezing throughout Sunday and this will certainly make a difference regarding the condition of the snow above 3000 feet.


Beyond Sunday, the outlook has trended more wintry and the period beginning March 2nd through around March 12th looks especially intriguing. I was reviewing Arctic Oscillation (AO) data through the early part of the season and noticed that since December 1, there has been only 1 period where the index went negative. It explains the lack of mid-latitude cold especially across the southern part of the United States. The only period where the index went negative was during 10 days in the early to middle part of this month during the period where the mountain received its multiple feet of snow. The second such period is likely to begin in early March and persist another 10 days or so. This will for a time be combined with the dip in the EPO (which is not expected to last) and the establishment of a nice blocking feature that appears fairly broad over the Bering Sea area. Winter will thus make a return to Vermont and I expect things to get exciting for a time.


Interestingly, the storm I have been especially disappointed with for several days. The one expected to consolidate over the Rockies early next week does not look nearly as organized or as consolidated on the models today. This means that the recent spring-fest might be over and sooner than expected with no return to excessive temperatures around the changing of the month. Precipitation could arrive as some snow on Tuesday February 28th although temperatures are likely only capable of supporting wet snow. Most of the model data does show a mixed bag of precipitation and even some rain before precipitation ends during the day Wednesday but this is a drastic improvement over what appeared to be another round of 50 degree temperatures and rain which was shown two days ago.


Colder and more legitimate arctic air is then expected to filter into the region by later in the week and that's when things could get interesting. The pattern is expected to remain relatively stormy thanks to  a multitude of intense looking systems that will impact British Columbia. These storms, and I expect there to be a few of them, will cross the Canadian Rockies and encounter the presence of the polar jet. Things could go array with one of these storms and warm Atlantic Ocean air might ruin a nice end game but if this happens at all, I'd expect it to be isolated to one event. What appears more likely right now is for some East Coast fireworks and a big snow producing system, at least one and maybe more, sometime in the time frame between March 2nd and 12th. Models are painting a variety of pictures on how it all might play out but lets just keep it simple and say that that there are multiple storm possibilities and expand on details later this weekend.

Wednesday, February 22, 2017

Early March could bring some excitement but we aren't out of the woods yet

With the help of some sunshine on Wednesday, temperatures have surged even higher than was expected. Good news if you like the soft corn, which we should have plenty of over the next few days but we are certainly not expecting any new snow in the short term. Thursday should again see temperatures soar but there should be more clouds and there could be a brief period of light rain later in the day.

As everyone is quite aware by now, our big weather system over the next few days approaches Saturday. Though we will see some more light rain or drizzle with impaired visibility Friday, most of the rain will come in one relatively well defined period after the ski day on Saturday. This means that the actual ski day will feature some pretty decent weather, especially if you like it very warm. The lower part of the troposphere is actually expected to mix out which will allow for some sunshine, very mild breezes and excessive temperatures for the season. Forecasts show readings in the low 50's, if you are watching your smart phone but with a little sun and a little wind, readings could approach 60 at the base. Needless to say, it will be an excellent spring skiing kind of day. The rain then arrives late in the evening and may fall somewhat heavily for a short time before colder air returns for Sunday.  Snow flurries are expected to accompany the colder air but accumulations are likely to be limited to an inch or two.

On Tuesday I certainly conveyed my frustration with this evolving weather pattern and it continues today. Though we expect a bit of cold for the early part of the week, it doesn't appear as if a sustained period of winter-like weather begins at least yet. A massive winter storm will hit the Rockies during the Monday and Tuesday time frame and because the jet stream became so amplified as a result of this weather system, it will allow mild air to take another run at the region by later in the week. There have been some hints that a piece of the Rocky Mountain system brings some limited snowfall to the region on Monday night or Tuesday but don't expect this to be our savior. What appears more likely is that some wintry precipitation arrives Tuesday night or Wednesday and then another onslaught of above freezing temperatures allows for another period of rain. Fortunately, this period of warm weather appears short-lived and colder air will again encompass the Vermont high country by later Thursday.

In spite of the less than ideal 7-day outlook, there are some encouraging signs regarding the overall weather pattern. Whether or not some of these developments can actually result in another sustained period of great skiing remains a big question. By early March, we are certainly going to see a drastically weakened jet stream in the Pacific which is measured by an EPO index that will be decidedly negative. Tag team this with a large ridge and for at least a short time in early March, a full scale blocking feature over the Bering Sea. We saw a similar type feature form in early December and the mountain got clocked with 4 feet of snow. In that particular case, the forecast suggested the high latitude block might situate itself over the Bering Sea and it ended up farther east over Alaska. That difference allowed much of Vermont to stay on the cold side of what turned into a rather striking north-south batttlezone of airmasses. This situation appears to have some similarities. The pattern will fully support a large amount of cold across the United States but a block across the Bering Sea certainly allows for the possibility of some warm air along the east coast.

It all boils down to what should be an interesting first half of March. I can't guarantee we will be on the right side of all the action (we could actually get another snow to rain situation) but we should see some cold, some storminess and if things break right, the mountain could certainly receive a good storm and multiple powder days.

Tuesday, February 21, 2017

Frustrating stretch of winter weather may continue thorugh part of next week

This has officially evolved into the kind of weather pattern I just outright despise. We have a bunch of warm days and a substantial amount of rain over the next few days. Yes colder weather does follow but the forecast data seems hellbent on creating an over-amplified negative PNA pattern which is fantastic if you ski in the west but not so much for the east.

Vermont managed to get a 36 hour reprieve from the thaw but temperatures have moved past the freezing mark as of midday Tuesday and for much of the rest of the week they will stay there. Specifically speaking,  Wednesday is primarily dry though cloudy with temperatures rising from near the freezing mark to near 40, Thursday we should expect to see more clouds with temperatures hovering near 40 and Friday the mild air will get an additional northward push and that process will allow for more clouds and some potential rain. Saturday appears to be a potential blowtorch with a sizable weather system tracking well into Quebec. Temperatures will soar into the 50's and a period heavier rain, even potentially a thunderstorm could impact parts of the state.

The forecast discussed in the previous forecast is certainly disappointing but not that surprising. We more or less knew this was going to be a rough stretch, we were simply hoping to merely minimize the bad. The most frustrating part of the outlook going forward lies beyond Saturday. Over the weekend and in spite of our rain, the jet stream in the Pacific will weaken quite substantially and by early next week, a large ridge and quite possibly even a blocking feature will develop in the Bering Sea. This should allow arctic air to move south toward much of middle latitude North America and it will, but much of it will attack the western United States as a storm is expected to amplify across the Rocky Mountains and bring widespread amounts of snow to western ski areas. This allows an upper level ridge in the western Atlantic Ocean to have a negative influence on our winter weather. The storm in the Rockies will move out over plains by around Tuesday and head toward New England. There will be a supply of cold air but an over amplified system in the plains will make it difficult to retain any of this cold. Snow and mixed precipitation would give way to move above-freezing temperatures and rain in such a scenario. We have to hope that the system doesn't consolidate across the west as is the current indication. It this happens the outlook for next week would improve dramatically.

Beyond the middle part of next week and into the early part of March, the negative EPO will continue to allow arctic air to have an influence over the region. But all of the major ensembles also continue to show repeated jet amplifications over the west and this is illustrated by the PNA outlook which is negative from day 5 to day 14. This is great news for the west as we head toward March but the bigger the storms are out in Colorado, Utah, Wyoming and Idaho, the worse our forecast will turn out to be. If some of these potential storms turn out to be weaker and a bit more disorganized, our forecast will get better.


Saturday, February 18, 2017

Tough stretch over the next week, but don't throw in the towel on winter yet

Yes, all good things must come to an end. 5 feet of snow in 3 weeks with a tiny bit of mixed precipitation in between is a welcomed event in any season. Temperatures have soared beyond the freezing mark early during the President's Day holiday and it marks the beginning of what we expect to be a rougher stretch of weather. I am hoping it only lasts a week, but the duration of our latest round of skiing adversity is the biggest weather question today.

A weak weather system will pass well to the mountains north on Sunday and do so rather innocuously.  That's a good thing because we lack the temperatures to support any snowfall as we will see another day with above freezing readings. Fortunately, this weather feature does have an accompanying cold front and this will usher in some cold Canadian air. New England will be the lone spot receiving any dose of winter from this as the rest of the eastern half of the country will continue the 2017 February mild-fest. Can't promise any snowfall for Monday or Tuesday, but temperatures will mostly be sub-freezing until late Tuesday afternoon when low lying areas may again top out in the middle to high 30's.

The culprit for the widespread warmth is another round of big time storminess that has already begun in earnest way out west. If you have been watching the news, you might have heard of flash flooding, mudslides and sinkholes in and around L.A. and San Diego. This level of storminess in the Pacific is often not a good thing (unless we get big time split flow) for winter in New England. The storminess will keep its distance from us for a time but by early Wednesday, we could finally see some light precipitation. We don't have the cold air to support any snow so we will probably just see some very light rain or freezing rain in a few spots Tuesday Night or Wednesday.

Another piece of Pacific stormy onslaught comes Thursday and again may spread some light rain into Vermont with temperatures generally in the high 30's. There is a minimal amount of arctic air available behind Thursday's weaker system and it remains a critical question how much of this we can tap into. Models have not been suggesting that mother nature is in the mood to dole out any favors but it's not a impossible scenario. That said, models have not been trending in our direction for what appears to be a stormier period between Friday February 24 and Sunday February 26h. In that time frame, a stronger storm system tracks from the eastern Rockies up through the central Great Lakes and eventually deep into Quebec. Models have over-advertised mild pushes in the past this year and I sure hope to god they are doing it again. If not, we are going to receive a round of rain and temperatures as high as 50 including 36-48 hours of well above freezing temperatures.

After Sunday, there is some better news stemming mostly from a large weakening of the jet stream in the Pacific Ocean and a rather assertive push by the EPO into negative territory. Limited blocking is expected to develop in coordination with all of this over the Bering Sea and parts of Alaska. This will allow Arctic air to make a late February return to the central United States. Some of this chill will make it to Vermont behind our potentially rainy system on Monday February 27th. All this is good news but ensembles right now have outright refused to eliminate the upper air ridging in the extreme western Atlantic. The suggestion right now is to have this pesky ridging thwart what could be the start of another nice stretch of winter for MRG and surroundings. There are hints of a follow up storm right around the turning of February into March but the aforementioned ridging in the jet stream could prove problematic.

For those ready to throw in the towel on winter, I wouldn't advise it. Even when the ensembles take a bad turn and produce a sour looking outlook, just wait two days and they tend to reverse. The negative EPO should above all else prove to be quite beneficial. It may just take some time to reap the rewards of this change.


Wednesday, February 15, 2017

Powdery Thursday and a slightly improved longer range outlook in spite of some milder weather

The Manitoba Mauler has spread very light snow into Vermont as of Wednesday afternoon. Models have finally forged a truce on this storm after arguing for days over subtle nuances. The bulk of the snow falls this evening, tonight and early Thursday as the system becomes better organized and strengthens into a poor man's nor'easter. Terrain will provide some assistance to snowfall totals as well, so I continue to expect some healthy 6-12 inch accumulations at MRG and some fantastic skiing on the mountain Thursday and Friday. The added snow Wednesday night and Thursday will pull the cumulative 3-week total to over 5 feet. Yeah we've had some mixed precipitation and ice in between but it's been an outstanding stretch.

Adversity is never far away in many Vermont winters and unfortunately a little bit of that confronts us now for the upcoming holiday week. Temperatures on Saturday will start in the single numbers but the higher angled February sun and a push of mild air will move temperatures toward the freezing mark. On Sunday, much of the day will feature above freezing temperatures but fortunately no rain.

A series of powerful Pacific weather systems is largely responsible for the milder temperatures in Vermont. Yet again however, interior New England is going to avoid the unmitigated blowtorch and the record-breaking warmth which has impacted a good portion of the central and eastern United States both last month and early this February. After Sunday, the jet stream will provide the region with just enough of a northwest to southeast trajectory to keep temperatures at least somewhat winter-like. By that I mean, low temperatures in the 20's and high temperatures Monday and Tuesday in the 30's. A couple of blog posts have highlighted the possibility of an intense mid to late week storm and that part of the outlook needs to be adjusted somewhat. One to two smaller pieces of some of the Pacific storminess will head towards New England Tuesday and spread a variety of precipitation types. The Euro has hinted that some of this could be snow while other models paint a somewhat rainier or icier scenario.

The possibility of a bigger storm has been pushed back toward later in the week and into the weekend. Any such storm would encounter the same challenges from a snow standpoint. There is no available cold air through the middle to late week period. That said, the jet stream in the Pacific will quiet down and allow this storm to pull in some colder temperatures and certainly allows for the possibility of a rain to snow  or a mixed precipitation to snow scenario over the weekend period of Friday February 24th to Sunday February 26th. For you model watchers out there, I know there have been some warmer scenarios shown with this storm but I would not give up on it, there is certainly a chance for a decent hit across interior New England by the end of the last weekend in February.

The longer range outlook has continued its tradition of oscillating back and forth beyond 12 days. It didn't look particularly great two days ago, it looks much better today beyond February 26th. Both ensembles have trended toward a much more negative EPO toward the end of the month which allows for the southward migration of cold toward the mid-attitudes.  All of this is vital as we move toward March and try to keep winter in play for as long as possible.