Think Snow, Tweet Snow !!!

Friday, December 31, 2010

2011 arrives with rain but favorable pattern re-emerges quickly thereafter

The thaw is underway across Vermont and many thaws in Vermont end badly for the ski hounds as rain can often highlight the grand finale of any warm spell. This will be no exception as rain seems intent on making an appearance with very late New Years Day or very early on the second. Until then it will be mainly dry with temperatures New Years Day climbing into the 40's. The rain will not be overwhelming with the consensus of information indicating about a quarter of an inch by first tracks time on the 2nd. Temperatures will be on the balmy side early Sunday but gradually turn colder and fall below the freezing mark again (after a 24-hour stint above freezing) by late morning Sunday. Snow showers and flurries are expected Sunday night into Monday but layer of instability does not look impressive and terrain induced snow amounts late Sunday into Monday will be in the 1-2 inch range if that.

As mentioned in the last post, another and very similar looking blocking pattern will emerge. The first chance for a "fluff up" comes late Tuesday into Wednesday from a clipper system that will pass through the Great Lakes and into the Northeast. The clipper could bring a few inches of snow to the mountain before reinforcing the winter-like temps for later in the week. A more significant storm late in the week may have our attention or may pass innocently to our south or not come together at all. Models have been a little skiddish so far on this hypothetical event but we could certainly use a big powder event going into the weekend of the 8th and 9th. More about that on Sunday. Until then have a Happy New Year and please be safe.

Tuesday, December 28, 2010

Warm-up on the way but December pattern my re-emerge to my surprise

The east coast blizzard was so close but yet so far. The big snow was more or less "a ridge away" with locations in the hills west of the upper valley receiving over a foot yet MRG got less than 4. Meanwhile another New York city mayor is getting crucified over the seemingly slow clean-up in New York city. He would not be the first to suffer through political misfortune because of a blizzard. In 1969 John Lindsay, the then mayor of New York had his political career ruined because of slow clean-up efforts following a major winter storm. 10 days later MRG got one of its most historic winter storms, so we can only hope for a repeat performance although there are no indications of this as of yet.

Instead, the weather will turn mild for a few days heading into the New Years weekend. Wednesday and Thursday will feature more sun, less wind and remain winter-like with temperatures in the single numbers during the morning and upper 20's to low 30's during the afternoon. We should also have some good visibility on both days. On Friday, temperatures should warm past the freezing mark softening the existing base and on New Years Day, readings could reach the 40's. This all results from a temporary relaxation in the pattern, driven mostly by Pacific Jet energy in the west which is expected to crush Colorado with snow and some big chill for them in the last days of 2010. The good news here is that we do expect this warm-up to be of a dry variety. Some showers might be mentioned in the forecast for Saturday but most of the day will be dry and the front which will be responsible for any rain will not bring a lot of it and probably not until Saturday night or early Sunday. Temperatures will then fall back under the freezing mark by later Sunday.

In my last update, I was encouraged somewhat at the expected shift of the PNA to positive and the appeared re-positioning of the ridge-trough pattern west by early January. All this will happen for about two days and then to my surprise another monster blocking feature will form across the Davis Strait and eastern Canada. In addition to this will be the formation of another ridge in the Bering Sea. Both these features will be the most significant on the upper air map by January 5th. This is very similar to much of what we saw in December. It wasn't a bad pattern overall but right now we are remembering it for a big rain event in early December and the big miss this past weekend. It did however yield over 80 inches of early season snow to the mountain which is a good total in the early going. If we can repeat that and avoid the rain, this upcoming month will be a pretty good one. That being said there are no significant events on the horizon and additional snow (of any significance) is not likely for at least a week. Talk of a storm may resume for the weekend of the 8th and 9th but we have a long way to go yet.

Saturday, December 25, 2010

Overnight models keep monster storm within 100 miles of the Cape

And the suddenly very inconsistent European model nearly had the storm on top of the Cape by Monday morning which was nearly a 200 mile shift west from its prior run. Such a scenario paints a snowier picture for Vermont Monday although the heaviest snow would still be to our south and east. The inability of our collective assortment of models to demonstrate any consistency or agreement from run to run underscores how tenuous any forecast is at this point. Much of the uncertainty at this point surrounds the rate at which the storm will deepen once it moves off shore. The lastest information is suggesting a much more rapid deepening, capable of resulting in blizzard like conditions for much of southern New England along with a paralyzing snow. A deepening of this magnitude would allow the storm to resist the eastward push it will be receiving progressing pattern.

NWS out of Burlington has tried to convey the snow risk by suggesting a 50-60 percent chance of snow for the region and using the headline "accumulating snow possible". This isn't a bad way to handle a rather tricky situation. We can certainly still take a big swing and a miss in regards to this system but at least we have a real fighting chance for a 6-12 inch event. Hypothetically, the snow would begin early Monday morning, several hours before first tracks time and persist through much of the day. We can certainly hope but expectations should be kept in check, it can go either way.

Friday, December 24, 2010

Post Christmas storm to track too far east for big snow

It was a question of a few hundred miles and it looks like that question will get answered in the wrong way for us powder hounds. Ideally, a low pressure center tracking between Boston and the Cape yields the best results for MRG and our surroundings. We have seen a convergence in the consensus of information over the past 24 hours and this is suggesting that the low will track at least 100 miles east of Cape Cod and the swatch of snow associated with this will be confined to eastern Massachusettes the southeast third of New Hampshire and coastal Maine. Its certainly is an unfortunate turn of events since sources of fresh powder over the next week or so appear limited.

Storms passing east of the Cape have been a recurring theme this month. The culprit for this lies in the prevailing pattern which has consisted of a mean ridge axis oscillating between the Dakotas and eastern Montana (a bit too far east for our liking). We have been saved on three consecutive weeks by the high latitude blocking to our north and east which has trapped many of these systems out over the Atlantic and moisture has been allowed to rotate its way back into the Vermont and New Hampshire high country. In this case the pattern will begin to undergo some changes and the position of this mean ridge will progres east and Pacific Jet energy will unload on the west. This "progression" in the pattern will also help move our storm out to sea at a very brisk pace and prevent moisture from this system from rotating back into the Green Mountains. In the end we may escape with a small of amount of snow Monday but our chances for epic powder are quite low at this point.

The middle part of the week will be mainly dry as I mentioned. Temperatures will be on the chilly side early in the week with readings close to zero both Monday and Tuesday morning and rising only into the teens during the day. Readings should rebound nicely Wednesday and Thursday however easily reaching the middle 20's during the afternoon and possibly approach the freezing mark. It will be very blustery early next week thanks to the strong off-shore storm but winds will subside somewhat during the middle of the week.

I scratched the surface a bit talking about some of the changes in the overall pattern and these changes will have a profound impact on the outcome for New Years weekend and beyond. Our Bering Sea block will vanish over the next 5 days or so and this opens the door for the Pacific Jet energy to unload on the west and for a big warm-up across a broad area of the eastern half of the U.S. including New England. The warm-up will be short-lived but there is a storm in here that will threaten to bring some unwanted ice and rain to the region during the first few days of the new year. We will keep some of the blocking in eastern Canada and some of this will extend back into western Canada allowing the PNA to turn positive for the first time in quite a while by early Jan. It will thus turn colder quickly in what should be an active start to the year. The pattern should consist of a active Pacific Jet, some arctic or at least Canadian air on the playing field and a few systems crossing the country over a 7-10 day period. If we get a more decisive turn in the PNA and the blocking across Canada eases somewhat it would open the door for some signficant weather systems to track in our direction but its a long way off. For now, Merry Christmas !

Tuesday, December 21, 2010

Christmas Storm prospects looking up...

and after a 4-8 inch fluff-up Wednesday and Wednesday night, the focus will shift to the period following Christmas Day as the possibilities for a major, major storm in that time frame have increased over the last two days. Until then we can enjoy the pre-christmas snow mentioned above and the crisp, relatively dry and partly sunny days that follow between the Thursday and Saturday.

The storm's energy stems from the feet of snow that is falling over the Rocky Mountains from the Sierra Nevada Mountains to Colorado. By early Christmas Day it won't look like too much with some rain falling along the Gulf Coast and snow across northern Alabama and eventually the mountains of north Georga, perhaps enough in those areas for an unusual white Christmas. Fortunately, for us the jet stream will be split and polar jet energy will dive south out of Canada and give this system a major infusion of upper air support as it encounters the relative warmth of the Atlantic Ocean. The result will be a rapidly deepening system either on or just off the Carolina Coast by early Sunday. I think we have figured this much out regarding this very important and quite possibly very ferocious weather system but its exact position Sunday morning and eventual track from here will be the determining variable. The American GFS model has flirted with a big east coast snow event with a few runs taking the system off shore and a few runs showing a northeast hit. A succession of European model runs however have been far more bullish and the relative consistency of this data has gotten the SCWB very excited. So long as we can track this storm reasonable close to the Atlantic Coast, there is a good chance some of the moisture can get caught under the blocking we keep talking about post after post. Although we can still get a complete miss out of this storm, the upside has become huge with more snow than I even dare mention early next week.

Any snow Monday and Tuesday will be followed by a dry and relatively tranquil period in the days prior to new years. Temperatures in the wake of a storm, or no storm will be chilly diving below the zero degree mark on one or two mornings and rising only in the teens. The early week chill will be accompanied by strong winds but both the chill and the winds will subside by later in the week making the late week skiing pristine if our above storm comes to fruition. For now we can at least be optimistic.

Sunday, December 19, 2010

Midweek snow will help but nothing spreads more holiday cheer than a Christmas storm, but we can only hope at this point

No major update is really required for the upcoming week but we do have a huge holiday week approaching and the last post didn't dive that period in too much depth. For the third consecutive week, we expect moisture from the a storm well out over the Atlantic to get sucked back into the high country of interior New England and deposit some snow for MRG and other places. As mentioned, it all results from the upper air block across eastern Canada which is more or less trapping this moisture over the Canadian Maritimes and allowing it to rotate back and around so it can be put to good use. As of this morning, the snow, which should fall in the late Tuesday to early Thursday time frame will be in the 4-8 inch range and although weather conditions might be a little windy, temperatures will be seasonable with 20's for high's and single digits or teens for lows.

Most of Thursday into Christmas Eve will be dry but the talk of the week will be a significant weather system that is expected to exit the central Rockies on the 23rd and progress west to east across the country on the 24th. Given its timing, the storm will garner some huge news headlines as it promises to be a major travel head-ache in a period where many like to travel. In addition the storm has the potential to impact a huge swath of metropolitan areas from the Midwest to Mid-Atlantic to northeast. This potential weather-maker has been very visible on a succession of model runs since last Friday but the consensus indication is that this storm will move off over the Atlantic before dealing MRG any huge powder. The upper air "block" over eastern Canada will largely be to blame if such an outcome occurs since although it can provide some needed protection from the ice and rain it can also encourage systems to track well to our south in a February 2010 style. Still it will not take much for our expectations to change. A slight shift in the track northward or an earlier northward turn would allow this storm to bring its moisture our way. Or, we could see this storm, like the previous three, get tangled in the blocking as it tracks off shore thus allowing its moisture to again rotate back in our direction.

Storm or no storm, cold and blustery weather will make a return in the days after Christmas and I am hoping some additional snows accompany this transition. I am becoming more and more confident that the threat of ice or rain in the period between the 24th and New Years Day is very low but after Christmas Day there are no real indications of a major weather system of any kind. We will more or less have to rely on weaker disturbances or passing clipper systems for additional powder. Overall though you can't complain since December skiing in New England has in some years been declared a total loss and is certainly not such this year.

Friday, December 17, 2010

5 days since the last post and not much has changed

Yesterday afternoon's European model run again allowed a major storm to "bomb" along the east coast and subsequently get caught under the high latitude block in eastern Quebec, dumping major snow's across Vermont and the rest of interior New England. The several pieces of model data released since yesterday afternoon have all suggested otherwise, keeping the storm well off shore and keeping the region very dry with the exception of a few flurries over the high country. This system is worth keeping an eye on but I am about ready to write this weather system off at this point. Unlike last weekend we will avoid the rain and continue to collect a dividend payment from a weather pattern fully energized by a very negative Arctic Oscillation. Two blocking mechanisms in this pattern are more or less conducting the orchestra; one I mentioned over eastern Canada and another over the Bering Sea. The Eastern Canada block has been so remarkable in its ability to draw incredibly mild temperatures deep into northern Canada. Temperatures on the east side of the Hudson Bay were all above freezing Thursday and Friday and the ice which had been expanding, actually receded a touch. The Hudson Bay has been slow to freeze this year and although Northern Hemisphere snow cover remains above average, open water on the Hudson Bay is not a particularly positive feedback for allowing cold to pool in eastern Canada and ultimately descend into northern New England. We will be alright for the time being but the aforementioned observation could come back to haunt us later.

Our next realistic chance for snow comes during the middle of the upcoming week. Again it will the blocked pattern which yieid another serving of mid-week powder. One weather system will move west to east rather quickly Tuesday and manage easily avoid the region passing well to the south. In the meantime energy in the North Atlantic will get sucked back under the block in eastern Canada and deposit some moisture across MRG and the rest of the Vermont high country during the middle of the week in the form of snow. Results similar to what the mountain saw the last few days are completely in the realm of reasonable expectations and a repeat of this should be enough to get the season started finally.

Another system should depart the mountain west just prior to Christmas and cross the country rather quickly. It will be difficult for these types of systems to make enough of a northward push to produce a major snowfall at MRG simply because the block in eastern Canada will exert some "downward" pressure on all such weather systems. Still, the pattern remains very favorable with a stretch of below freezing temperatures and at least some new snow for this week and a negative AO which should ensure more of the same (at the very least) for Christmas week. Even if we don't get a big storm, we can do a lot worse and have in the past had some horrendous holiday periods. Enjoy the weekend and don't just think snow, think "additional snow"!!!

Sunday, December 12, 2010

Another setback but another big week for new snow

43 degree dewpoints, heavy rain and a tarnished MRG base is not exactly putting me in the Christmas spirit early this week. The Sunday/Monday storm turned into a fiasco and a major setback to what was a promising start to December. In truth, this resembles much of what was expected this winter, a roller coaster ride of weather results and in this case it was 30 inches of snow followed by over an inch of rain. The proverbial "silver lining" does exist and the high terrain of northern Vermont should make a rapid and an eventual full recovery.

Rain becomes light snow by Monday evening as temperatures slowly make a return to the freezing mark. We will then watch the sequel to last week and hope the sequel is as good as the original. Sunday's big rain-maker will get caught underneath all the high latitude jet stream blocking and a second piece of energy with a fresh supply of Atlantic Ocean moisture will migrate northwestward toward interior Quebec. Moisture from this system will arrive Wednesday and this should occur after an initial few inches of backlash snows Monday night into Tuesday. Snow totals between Monday night and Thursday will be in the 8-14 inch range and the high elevation areas will have a big edge.

Heavier snow showers will taper to flurries later Thursday and continue into Friday. Much of the country will have experienced some well below normal temperatures this week but readings in Vermont will be very ordinary ranging between the teens and low 20's. By this weekend, a weather system will be tracking into the Tennessee Valley and will bring both rain and snow to the Ohio Valley. Most of the model runs have taken this system well out over the Atlantic Ocean but we did get a European run this afternoon which allowed this system to develop into a major coastal storm and a big snow producer for most of New England. Its worth watching for sure but we should wait for more evidence before getting our hopes too elevated.

Even should any hypothetical late weekend storm turn into a "non-event" we should remain optimistic as the pattern remains anchored by a very negative Arctic Oscillation. The negative AO will peak in the next 7-10 days as a massive block covers the Baffin Bay and much of the southern Arctic Ocean. Another weaker block will remain in place across the Bering Sea. Much of the U.S. will thus remain in the firm grip of below normal temperatures as a result of all this. Temperatures across Vermont will remain close to normal but smaller disturbances should allow for powder possibilities through the Christmas holiday. Stay dry this Monday, new snow and a return to winter is not far away.

Thursday, December 9, 2010

Storm Sunday/Monday to bring rain than snow....

but the pattern will be generally favorable through the time of the winter solstice and this sets the mountain up rather well for the holidays. The storm in question is a "BC bruiser", and a rather innocent looking one it will be as it crosses into southern Alberta and dives southeastward from there. The storm will get turbo charged by a huge injection of polar jet energy which will more or less bomb the system out before it even interacts with the Atlantic Ocean. This is a bit problematic for interior New England since surface pressure's associated with this weather system will be so low before it even crosses the Appalachian Mountains thus making it difficult for a successful transformation off the Atlantic Coast. Many storms that track in this fashion lay flatter and are initially weaker but this one will be quite strong and will be standing quite upright and thus envelop warm Atlantic Ocean marine air across New England. The result will be a widespread rain event across southern New England and a mixed precipitation to some rain type of event across northern Vermont. Since the mountain has yet to open, it isn't the end of the world but it be good if we can keep dewpoints close to the freezing mark and keep the wind down. Both are huge factors relating to the rate at which snow can melt. The former appears better than the latter as I would guess dewpoints remain in the 30's but the wind gets whipped up pretty good by early Monday morning.

This storm, like the prior event will also get caught underneath the mammoth block over Greenland and as temperatures rapidly turn colder late Monday, moisture from the trapped system will rotate back over New England and deposit some additional snows across the region between late Monday and Wednesday. Snow totals in this period could approach a foot but its a bit early to tell for sure. With a solidified base and some additional snow next week, the mountain could be in good enough shape for an opening on MRG's target date but much will depend on the damages done Monday morning.

Teleconnection indices remain rather favorable as I mentioned above let mostly by the Arctic Oscillation which will remain very negative. The block over Greenland will migrate into eastern Canada a bit and will limit the region's access to any fresh supply of cold air after Tuesday even though it is not expected to be extremely mild (just above normal). The prevailing storm track however should be good enough to allow for the chances for additional snow from another storm toward the weekend of the 18th and 19th. More on that in a subsequent post Sunday.

Monday, December 6, 2010

Snow totals adding up, big storm to watch Sunday/Monday

Light to moderate snow will continue through Tuesday before tapering to flurries Wednesday. With 10-plus inches of new snow the mountain will have a powdery finish and an appealing look but the base will remain shallow and appropriate only for your pair of rock ski's you would have otherwise advertised on Craigslist for $20. We do have a weather pattern anchored by a nasty Greenland Block and negative NAO and this will allow for the continuation of below freezing temperatures and is certainly setting the stage for an early season big storm and we will get our chance on the 12th or 13th of the month.

There will be two jet stream disturbances that will move quickly eastward out of the Pacific Northwest late this week and the weekend. The first, can be described as an alberta clipper which will spread light snow across the Great Lakes and ultimately interior New England early Saturday. This first feature can be compared to trying to start your lawn mower for the first time in two weeks. It will pull hard but the mower won't start and the moisture and upper air support will be lacking and so will the snowfall. We will hardly notice its presence in the end and will instead be focused on the second feature which will dig and dig hard as it progresses into the middle of the country. The amplification with this second feature (originating from the BC coast) will be very rapid and occur very quickly. Too quick for comfort perhaps as the surface low pressure center will gather steam in the Ohio Valley and like many storms during La Nina winters, head into New York state and interior New England. It will be a track that promises to bring the threat of all types of precipitation and although we have a chance for a major snow storm, precipitation could change to a sleet/freezing rain mixture and perhaps even rain. Hopefully this system can make an important jump to the coast before tracking up toward the St Lawrence Valley. Many storms which encounter a mammoth Greenland block such as this one will make this jump and we will need it here to make this event a big success.

Colder weather and snow showers will follow for early next week and with the negative NAO dominating the field of play, below freezing temperatures and continuous chances for snowfall will continue through 17th-18th of December.

Friday, December 3, 2010

2010-11 season to start with a huge bang

Thanks largely to a well established upper-air block in the jet stream across Greenland and the very negative NAO which is a direct result. This is the very same feature which dominated the weather pattern last year, a year where the blocking was so severe and the southern branch so powerful that a succession of storms tracked well to the region's south. A similar pattern this year will yield much more fruitful results as the upcoming week will prove. Our live look at the MRG base might not show much in the way of snow at the moment but the view will be very different in a week's time and discussions of a very grand opening will pick up in earnest !!

Colder weather, which is dominating much of the central part of North America has been a little sluggish in its eastward progression leaving much of interior New England "above normal" though readings have fallen below the critical freezing mark across higher terrain. This will remain the case over the next few days as we witness the Midwest and deep south get a surge of chill by the 5th of the month. As the cold moves south, a storm will take shape across the Gulf of Maine and intensify very quickly. I alluded to this feature in the last post as a possible snow maker and it should prove to be of much greater significance than originally thought. As we progress into early next week, this storm will get caught under the all important Greenland block and retrograde into Quebec. As it does so, a moist conveyor will rotate into the northern Green Mountains and snow will begin to accumulate across much of northern Vermont although the high country will receive the biggest benefits. Between Monday and Wednesday snowfall totals could range in the 1-2 foot category.

The upper trough axis will shift east later in the week and temperatures should fall dramatically by Wednesday. Snowfall late in the week will largely depend on the available low level instability because the Champlain powder machine should be open for business (with the lake being unfrozen). It is tough to tell this early how deep that layer of instability will be but a subsequent post can fine tune that forecast.

Of more significance could be a more potent weather system which should exit the Rockies late next week and have a bit more moisture to work with as it proceeds east toward the region. This storm will be a product of a more consolidated jet stream this year and like many systems this year, the question will be its ultimate track and its ability to gather moisture from the Gulf Mexico since many such weather systems can struggle somewhat in this regard. Even at this early juncture I feel relatively confident for additional snows next weekend and this will make for a fantastic 7-10 days of early season skiing across northern New England. The even better news is the recent indication from the European Ensemble package which suggests a continuation of a blocked up and negative NAO dominated pattern through the 15th to 17th of the month. This will really limit the chances for any significant thaw or rain through the middle of December.

Lastly, I wanted to expand on this whole "favorability index" theme which will be a more objective measure of the three teleconnection indices that the SCWB keeps an eye on. The index is a cumulative measure of the NAO, PNA and AO over the next two weeks with the signs of the NAO and AO flipped. More importantly, a favorability rating of over "2" is excellent while anything under -2 is rather unfavorable. Hopefully this will keep me honest and perhaps keep me out of trouble !! Enjoy the early season turns.