Think Snow, Tweet Snow !! - @SingleChairWX

Monday, February 6, 2012

You can't spell "Elite" without E-L-I but its time to focus on spelling out the word "Snow"

It was another terrific Pats vs Giants Super Bowl and a thrilling victory for the G-Men. A few bounces here, a less banged up tight end there and things could be different so I solute the Patriots for a great season and a great effort. For a while there, I thought they had the Giants "D" figured out. All that said, Eli needs to get the credit he deserves. Yeah he has some great receivers to throw to, but the whole "Awww Shucks" thing everyone gets on him for serves him well. He has the uncanny ability to shake off all the pressure and make big throw after big throw no matter the gravity of the situation.

So the Giants did their part, it is now mother nature's turn. Let me preface the following by stating that I am going to only remain cautiously optimistic since selling my soul to powdery forecast has done nothing for us. We are finally in the throws of a generally favorable high latitude blocking pattern but we continue to wait for the snow. We had alluded to a weaker disturbance that had the potential to freshen things up for Thursday but this will slide innocently to the south. Temperatures with the help of sunshine, will exceed the freezing mark for a few hours both Thursday and Friday afternoons

That brings us to the weekend and the big southward advance of the Polar Vortex. To a weathergeek like me, anything with the word "vortex" is going to be exciting, so I consider the "PV" to be a fun topic of conversation. In the two days since the last update I had hoped we could better sort the picture out this weekend. We have made a little progress but uncertainty remains. Generally speaking the Euro still shows a softer PV invasion and as a result, a clipper system is able to get some traction with moisture from the Atlantic Ocean and spread snow across interior New England Saturday. The American model shows the PV overwhelming the region resulting in a very cold but generally drier forecast. I am more inclined to side with the Euro on this although not wholeheartedly. This would mean our next chance for accumulating snow is Saturday.

A second impulse Sunday could bring another round of snow showers but it will be remembered more for triggering the southward advance of what is likely to be the coldest weather of the season. Bitterly cold temperatures is typically the end result of any intimate relationship that develops between New England and a Polar Vortex and this should be no exception. Temperatures of 15 or 20 below zero Sunday night or Monday is not out of the question.

The longer range outlook has improved slightly. We should see a significant temperature moderation by the middle of next week but the pattern looks significantly more active. This includes two potential precipitation producers in the period between the 14th and 18th of the month. Although the AO is expected to remain negative the ridge/trough axis across North America will shift west. It will resemble a fairly typical La Nina set up but I am hoping the support of the AO on the favorable side of what could be a succession of storms.

No "kiss of deathing" allowed in the comments section !!! Lets keep it clean ;)

Sunday, February 5, 2012

Snow remains a possbility late in the week

At the very least, I hope we are at the beginning of a long stretch void of any rain. We are expecting above-freezing temperatures Monday but we should keep this short streak alive as temperatures for the remainder of the week return to seasonable levels without rain. It has been an annoying habit on the blog to keep pushing back the next chance for snow. We won't do that this time which is a moral victory of sorts. What looks to be the most pathetic of disturbances will undercut the large western ridge and bring moisture into New England Thursday. This occurs just prior to when the Polar Vortex across Canada makes its southward descent into the United States. The weak weather system Thursday is nothing you can take to the bank but could provide the region with 1-4 inches. The arrival of the Polar Vortex also brings the chance for snow but this too is uncertain. If the PV progresses slow enough it can allow time for its associated clipper system to interact with the Atlantic, strengthen and spread more significant snows to both the Green and White Mountains in the Friday/Saturday time frame. If it makes a rapid descent, it will simply overwhelm the pattern and suppress any storm development. We would thus see only a period of snow showers before it turns bitterly cold for the weekend. Models have been provided a variety of answers to these questions but its nice to see two chances for at least some powder in the 2/9-2/11 time frame.

Beyond next weekend marked an even more uncertain time as indicated in the last update. The American GFS Ensemble indicating cold the European Ensemble back to warm. Both packages however showed the all important very negative AO. As of the current update both continue to show the negative NAO and have added a little more clarity in the form of a compromise. The bitterly cold temperatures that should dominate for the weekend will give way to yet another warm-up in the Monday the 13th to Wednesday the 15th time frame. The warmer temperatures could prove to be a another perilous stretch but it should be temporary as the support of both the AO and NAO should allow for the return of both colder temperatures and snow to return for the President's Day holiday.

That is all for now, enjoy the Super Bowl, it should be a good one.

Thursday, February 2, 2012

Cooler temperatures return but we are dry for another week

Across the entire continent of North America, there is only significant weather producer. Its a significnat one, a blizzard, poised to bury much of eastern Colorado with snow. Eastern Colorado and western Kansas are lonely places however, void of mountains and most vegetation. Resorts such as A-Basin, Keystone, Copper, Vail and Aspen are in the central and western sections of Colorado, west of the divide. Those areas will actually only get a few inches out of this storm proving that it has been a very painful year for almost everyone. The exception ? The Canadian Rockies which has reaped the benefits of the same very active Pacific Jet stream I have been groaning about all year.

The "loosening" of this active Pacific Jet will occur on schedule and the result will be the development of a large upper level Ridge across western North America. This feature will be the biggest in the Northern Hemiphsere for a period of a few days, so big in fact that it will take longer to funnel cold toward the eastern third of North America. Temperatures will be close to seasonable this weekend but the "blizzard" across the western Plains will not have a reinvigorating catalyst when it moves east and it will innocently move toward the Mid-Atlantic coast late Saturday then off the coast Sunday without threatening any part of New England with precipitation.

The beginning of next week is also expected to be benign with temperatures making another charge toward above-freezing levels Monday afternoon. Tuesday should see more clouds as the front marking the leading edge of colder temperatures marches southeast. This front will be riding the momentum of the aforementioned western ridge, it doesn't have much in the way of moisture to work with but flurries or a brief period of light snow is possible Tuesday and Tuesday night before another we enjoy another dry and seasonable day Wednesday.

The next chance of significant snow will come toward the end of next week in what appears to be an interesting time frame. As next week continues to progress, the ridge across the west will allow a polar vortex to move south from the polar regions to eastern Canada. Recent runs of many of the computer models have suggested that the impact of this "PV" will be confined to eastern Canada and the northeast U.S. next weekend. Certainly it could result in some of the coldest weather of the season but we are in dire need of a bit more than just bitter chill. We need some of this "PV" energy, even a small piece of it, to combine with undercutting Pacific energy to produce a storm. Its not an impossible task but requires "split flow" in the jet stream. The polar component of the flow looping around the western ridge deliving us the cold and upper air support and a southern branch of the jet delivering the moisture. We haven't heard much talk of "split flow" the last two years since La Nina makes it a tough sell. I would love to see it return however since it has certainly provided us with some epic times.

So we think a vague picture has emerged regarding next weekend including cold weather and hopefully at least a little new snow. Beyond that however begins an all out war between the two major ensemble packages. It is one of the biggest disagreements I have ever seen in the 10-15 day time frame. Interestingly, both ensembles keep a blocking pattern in place through the AO. The European however destroys the western ridge completely, showing another sharp tightening of the Pacific Jet and ultimately a return to zonal flow across the country. The American GFS weakens the western ridge but does not eliminate it. Instead, ridging that stretches from the North Atlantic, over Greenland and to the poles evolves gradually into a large "block" that allows for a continuation of both cold and frequent chances for snow. The European has been winning these arguments for much of the year but this battle has not been fought with the underlying teleconnection indices as favorable as they are now. I remain frustrated but have not abandoned hope.

Tuesday, January 31, 2012

Ugh, two potential storms look dead

During the last update I had actually tried to reign in my excitement over what I thought could be an epic three weeks on the single beginning in early February. It was a very enthusiastic but non-specific update a few days ago. At that time models had indicated upwards of 4 significant snow events in a 10-12 day stretch. Within a day of that update, models had eliminated almost all of it and indicated a weather pattern not nearly as productive. I try really hard not to get overly theological regarding the "kiss of death" and then something like that happens and suggests that perhaps I would be better served blogging about the inevitable "doom and gloom" of this winter.

Is it really that bad ? No. We still only expect one "thaw" day Wednesday before temperatures turn colder but we lost the shot at a storm late in the week. Much of that energy will get held back in the western plains and that is where some of our problems begin. The failure of that system to phase with some of the incoming polar energy this weekend creates a disjointed jet stream rather than a clearly amplified pattern. When the western plains storm finally ejects itself into the Midwest, it will get shunted southward by a polar jet that will have already played its hand.

Overall though the pattern will be highly "blocked" for the next two weeks. The ridge across western North American will develop as advertised and allow a continuous throng of cold shots into New England to keep it wintry (although models have backed off on the intensity of the cold). Snow-wise however we are probably a week or so away from a potential powder producer. The weekend should stay mainly high, dry and seasonable. Not a bad one to be outside but at this point I would expect little or no fresh powder. By the middle of next week we should have a clipper that could yield some of the good stuff. This will be followed by a surge of colder temperatures and potentially a more organized storm system prior to the weekend of the 9th and 10th.

Still a relatively good stretch of weather, but I want more and am not happy with the way things are trending.

Sunday, January 29, 2012

No more consolation prizes, pattern looking golden by the weekend

It is now just a few days away. A few days and things should really start to get interesting at MRG. Two months of trying to make the most of a mostly lousy weather pattern and finally as we move toward February the stars align. The jet energy across the Pacific Northwest will undergo a complete collapse over the next week allowing a large ridge to develop across the western United States. Even better, this ridge will extend northward over western Canada right along 135 west ultimately reaching the polar regions. It is a development that should make us ecstatic since not too many weather features can make me as happy. The ridge across the west will eventually combine forces with another large ridge across over Greenland. Hopefully, the whole thing just turns into one big "high latitude block party". All the cold and snow can descend into the mid-latitudes and do so for an extended period of time.

There is a lot of potential over the next 2-3 weeks. Clippers, East Coast bombs, Gulf of Mexico monsters. We have the potential for all of it and we have earned it since we have certainly done enough time in the can this winter. I won't get too specific with this update. There is some powder to ski Monday and the push of warm air Wednesday will have an inch or two of snow preceding it on Tuesday. The Wednesday warmth however is a one day event. One afternoon of above freezing temps before the talk shifts to snow and eventually cold. Our first potential storm comes from a southern Rockies weather system that will push through the Midwest Thursday. Models are all over the place with this system. The Euro shows a nice hit Friday for most of Vermont but there are a few contrary opinions. As this new and much more amplified weather pattern begins to take shape over the weekend of the 4th and 5th, the chances for powder start coming from everywhere and very frequently. For example, several model runs have a Gulf of Mexico low pressure area blowing up and evolving into a massive snow producer in the Sunday/Monday time frame. Additional reenforcing amplifications throughout next week will provide more snow possibilities. It should be a good time to be alive in Vermont so as Bob Dylan used to say get busy doing it.

Thursday, January 26, 2012

Nice stretch of winter starts around February 3rd

Rain on top of the freezing rain/sleet on top of a few inches of snow is the process by which concrete is made, or at least that is how I learned it. The 3-inch concrete slab is not exactly ideal when its plastered on top of 40 inches of powder. We don't have 40 inches of powder though so the concrete slab could be the start of the long road back.

Wintry weather should return for the weekend although temperatures will remain on the mild side Saturday. As mentioned in the last update, an eastern North American trough amplification will interrupt the mild pattern for a few days and embedded within this trough are two impulses capable of delivering the mountains some snow. The first rotates through the Great Lakes Saturday and spreads snow showers in the Green Mountains Saturday night. This particular weather feature is probably good for a 1-3 inch dust up but it will drop temperatures back into the 20's for Sunday (from the 30's Saturday). The second feature looks like a more traditional Alberta Clipper. It will bring some snow to MRG Sunday night setting the stage for a chilly but semi-powdery Monday. The system Sunday night has the look of a 2-4 inch event but this could change in the days ahead

I am certainly more encouraged about the way things may play out next week. Arctic chill will be able to maintain its footing through Tuesday morning before milder temperatures make another northward charge. I had advertised the possibility or record warmth a few days ago. That appears a little less likely now but more importantly the recent run of the European model showed the overall mild pattern more or less collapsing on itself late next week under the weight of what could prove to be an intriguing weather feature. I do feel fairly confident overall that ultimately, we will see some critical loosening of the Pacific Jet and a reversal of the PNA by Super Bowl weekend. How fast these changes manifest themselves into some tangible powdery goodness remains a question. There are hints that things could get very interesting along the east coast in the period between the 2nd and 5th of Feb. We have yet to see any real consistency but whispers of an east coast "bomb" began and I hope we can turn this into some real talk.

At the very least however, we should be able to look forward to an exciting 7-10 day stretch of weather beginning around the time of February 3. The PNA will be very supportive and will be coupled with at least some weak high latitude blocking either over Greenland or over the Arctic regions.

Tuesday, January 24, 2012

Close call Friday but not looking good, weekend still looks wintry

We are in the midst of a very lousy upper air jet stream pattern. We paid for it Monday with mild temperatures and rain. We will likely pay for it again next week. Friday however remains a close call and the upcoming weekend will mark an interruption from the prevailing theme of the week. Models have had a very difficult time with Friday's system and the forecast has remained in an invariable state of flux for a few days. It looks as of now as if we will get an organized weather system fueled by Gulf moisture arriving Thursday night. There is almost no available cold air in the vicinity thanks to a dominant upper ridge positioned across eastern Canada. There is a little support coming from a polar-pacific impulse. It will dive underneath the Canadian ridge and attempt to inject a little bit of chill along with guiding the storm south of the St Lawrence Valley. It may not be enough in the end but its a close call. Precipitation will begin in the pre-dawn hours Friday and persist through a good part of the day. My guess right now is for an event consisting of sleet, freezing rain and some rain but it is close and a small change could improve the forecast. Areas north of Smuggs stand a better chance of getting some snow out of this system.

The weekend does mark a break from the madness of the mild air. We should get albeit temporary but significant east coast trough amplification. The result will be more seasonable and even below normal temperatures but it should also mean snow showers later in the day Saturday into Saturday night. The best chance for a powder day would be Sunday. I woudn't expect epic snow but a few inches is certainly possible.

The cold weather will persist through Monday but we will again see the reemergence of a dominant upper ridge that spans all of eastern North America. The coupling of Pacific energy and trough over Alaska and the ridging in the mid-latitude Pacific is just killing us. It is causing Pacific air to run the country over and in this case it will trigger record warmth across parts of the east coast and quite possible interior New England by the middle of next week.

Fortunately the winter thaw does appear to have an end on the horizon. By about the time of Super Bowl weekend there is evidence of a loosening of the Jet in the Pacific and a re-positioning of the ridge over North America farther west. This will allow the PNA index to go from highly unfavorable to favorable while the North Atlantic oscillation remains slightly favorable with slight evidence of blocking over Greenland. I know it hurts but keep the faith, we still have time to save the Presidents day holiday and beyond.

Speaking of the Super Bowl, we have a Giants vs Pats rematch which I am sure many loyal MRG skiers against one another. It was a game for the ages last time and I fully expect another one this go around. What I will never forget about 2008 however was the incredible rally we got in the weather in the week that followed Super Bowl 42. It looked for all the world that we would get 2 days of rain 40 degree temperatures. Suddenly, the Giants upset the Pats and just as dramatically the weather forecast shifted. Arctic air fought its way into interior New England and a train of low pressure systems delivered MRG like 30 inches of powder in 3 days.

Yeah its a reach but I am feeling around for some karma !!